WO2024026970A1 - 导电膜及其制备方法、电极、集流体、二次电池及装置 - Google Patents

导电膜及其制备方法、电极、集流体、二次电池及装置 Download PDF

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WO2024026970A1
WO2024026970A1 PCT/CN2022/117038 CN2022117038W WO2024026970A1 WO 2024026970 A1 WO2024026970 A1 WO 2024026970A1 CN 2022117038 W CN2022117038 W CN 2022117038W WO 2024026970 A1 WO2024026970 A1 WO 2024026970A1
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layer
phase
alloy
porous
base layer
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PCT/CN2022/117038
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English (en)
French (fr)
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王慢慢
葛销明
欧阳楚英
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宁德时代新能源科技股份有限公司
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/64—Carriers or collectors

Definitions

  • the present application relates to the technical field of metal materials, and in particular to a conductive film and its preparation method, electrode, current collector, secondary battery and device.
  • secondary batteries are widely used in energy storage power systems such as hydraulic, thermal, wind and solar power stations, as well as power tools, electric bicycles, electric motorcycles, electric vehicles, Military equipment, aerospace and other fields.
  • energy storage power systems such as hydraulic, thermal, wind and solar power stations, as well as power tools, electric bicycles, electric motorcycles, electric vehicles, Military equipment, aerospace and other fields.
  • secondary batteries have achieved great development, higher requirements have been placed on their energy density, cycle performance, etc.
  • Lithium metal is considered an attractive anode material for high-energy lithium-ion batteries due to its high theoretical specific capacity (3860 mAh/g) and low electrochemical potential.
  • batteries using metallic lithium as the negative electrode will have the following problems during the cycle: lithium dendrites are generated, chemical reactions occur with the electrolyte, and the volume of the lithium negative electrode expands infinitely during deposition and peeling. These problems will inevitably bring about battery safety risks and Low cycle efficiency seriously hinders the practical application of metallic lithium anodes.
  • This application was made in view of the above-mentioned problems, and its purpose is to provide a new type of conductive film and its preparation method, electrode, current collector, secondary battery and device.
  • the novel conductive film of the present application has a laminated base layer and a porous layer.
  • the porous layer contains an innovative porous conductive material with unique multi-level pore size distribution characteristics.
  • the porous conductive material is beneficial to the infiltration of the electrolyte and the deposition of the active material.
  • the base layer of the conductive film plays a role in supporting the porous layer and improving the strength of the conductive film.
  • the conductive film of the present application has both good mechanical properties and electrochemical properties.
  • a conductive film which includes:
  • a base layer the base layer has a first surface and a second surface arranged oppositely, and the base layer has a dense structure
  • a first porous layer, the first porous layer is laminated and bonded to the first surface of the base layer;
  • the first porous layer includes porous conductive material
  • the porous conductive material has pores of a first pore size and pores of a second pore size
  • the first pore diameter is n microns, 0.5 ⁇ n ⁇ 10;
  • the second pore diameter is m nanometers, 20 ⁇ m ⁇ 200.
  • the conductive film of the above solution has a base layer and a porous layer that are laminated and combined. Among them, the porous layer has relatively weak mechanical strength due to its porous structure.
  • the above solution uses a base layer with a dense structure and a porous layer to be laminated to obtain a porous conductive film with enhanced mechanical properties.
  • the base layer with a dense structure has good mechanical properties
  • the porous layer with a unique porous structure exhibits good electrochemical properties for secondary batteries.
  • the conductive film has both enhanced mechanical and electrochemical properties and is suitable for use as an electrode/current collector for secondary batteries.
  • the conductive film of the above solution contains a new porous conductive material, which has a new multi-level pore size distribution characteristic.
  • the new porous conductive material is particularly suitable for use in anode-free metal batteries (such as anode-free lithium metal batteries or anode-free sodium metal batteries) or batteries containing active metal/alloy anodes.
  • the inner wall of the hole with the first pore diameter (referred to as macropore) can serve as a substrate for active material deposition; in addition, another function of the macropore is to provide an electrolyte infiltration channel.
  • the inner wall of the hole with the second pore diameter (referred to as the small hole) can serve as a base for active material deposition.
  • the small pores increase the specific surface area of the material, allowing the porous conductive material to load more active materials; in addition, another role of the small pores is to serve as a template for the deposition of active materials.
  • the active material deposited in the pores has a nanoscale size.
  • the nanoscale active material has a high ionic conductivity due to its small size, which can improve the overall ionic conductivity of the electrode. rate, thereby improving the rate performance of the battery, and ultimately improving the capacity, cycle stability and rate performance of the battery as a whole; in addition, another function of the small holes is to limit the volume expansion of the active material and avoid its pulverization failure.
  • the conductive film further includes a second porous layer, the second porous layer is laminated and bonded to the second surface of the base layer; the first porous layer and the second porous layer each Independently includes a porous conductive material; the porous conductive material has pores of a first pore size and pores of a second pore size; the first pore size is n microns, 0.5 ⁇ n ⁇ 10; the second pore size is m nanometers, 20 ⁇ m ⁇ 200.
  • the conductive film based on this solution has porous layers on both sides of its surface. Both sides of the conductive film can be used as collecting surfaces for active materials.
  • the conductive film is used in secondary batteries.
  • the secondary batteries show improved capacity and cycle stability. performance and/or rate performance.
  • the porous conductive material has an apparent volume V
  • the pores having the first pore diameter have a total pore volume V 1
  • the pores having the second pore diameter have a total pore volume V 2
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the apparent volume of the porous conductive material is V
  • the total pore volume of the pores having the first pore diameter is V 1
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the apparent volume of the porous conductive material is V
  • the total pore volume of the pores with the second pore diameter is V 2
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • adjacent pores having the first pore diameter are separated by first ribs, and the average rib diameter of the first ribs is 0.89-3 ⁇ m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • adjacent pores with the second pore diameter are separated by second ribs, and the average rib diameter of the second ribs is 27-100 nm.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the total specific surface area of the pores having the first pore diameter is 0.08-1.32 m 2 /g.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the total specific surface area of the pores having the second pore diameter is 0.87-5.25 m 2 /g.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the porous conductive material has a specific surface area of 0.95-6.57 m 2 /g.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the thickness of the base layer ranges from 4.5 ⁇ m to 12 ⁇ m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the first porous layer has a thickness of 50-200 ⁇ m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the thickness of the second porous layer is 50-200 ⁇ m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the porous conductive material is made of a metal element or alloy containing M element, and the M element is selected from copper, aluminum or a combination thereof.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the base layer has a tensile strength of greater than 330 N/m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the conductive film has a tensile strength of greater than 100 N/m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the material having a dense structure means that the apparent density of the material is substantially equal to the actual density, for example, the apparent density is equal to more than 90%, such as more than 95%, such as 100% of the actual density.
  • the base layer has a single-layer structure or a multi-layer structure.
  • the base layer has a multi-layer structure.
  • the base layer includes a main body layer and a first conductive adhesive layer stacked on one side of the main body layer.
  • the first conductive adhesive layer faces away from the surface of the main body layer. Constituting the first surface of the base layer.
  • the base layer has a multi-layer structure.
  • the base layer includes a main body layer and a first conductive adhesive layer and a second conductive adhesive layer respectively laminated on opposite sides of the main body layer.
  • the first conductive adhesive layer The surface facing away from the main body layer constitutes the first surface of the base layer, and the surface of the second conductive adhesive layer facing away from the main body layer constitutes the second surface of the base layer.
  • this application provides a method for preparing a conductive film.
  • the definition of the conductive film is as described in any of the above solutions.
  • the preparation method includes:
  • a raw material base layer has a first surface and a second surface arranged oppositely, and the raw material base layer has a dense structure
  • a first A alloy layer is laminated and bonded to the first surface of the raw material base layer.
  • the material of the first A alloy layer is a multi-phase alloy.
  • the multi-phase alloy contains ⁇ Mn phase and (M , ⁇ Mn) phase, the M element is selected from copper, aluminum or a combination thereof;
  • the first B alloy layer is laminated and bonded to the second surface of the raw material base layer.
  • the material of the first B alloy layer is a multi-phase alloy, and the multi-phase alloy contains ⁇ Mn. Phase and (M, ⁇ Mn) phase, the M element is selected from copper, aluminum or a combination thereof;
  • the raw material base layer is configured to remain intact during the dealloying process.
  • the above method cleverly utilizes the different chemical reactions of the ⁇ Mn phase and (M, ⁇ Mn) phase in the multiphase alloy during the dealloying process.
  • the ⁇ Mn phase is removed during the dealloying process to form a pore with a first pore diameter
  • (M, ⁇ Mn) phase is removed during the dealloying process to form pores with a second pore size, thereby obtaining a conductive film with a novel porous structure of the present application.
  • the method for preparing a conductive film of the present application also includes the step of preparing a first raw material multilayer body, specifically including:
  • the second raw material multilayer body including:
  • a raw material base layer has a first surface and a second surface arranged oppositely, and the raw material base layer has a dense structure
  • a second A alloy layer is laminated and bonded to the first surface of the raw material base layer, the second A alloy layer contains (M, ⁇ Mn) phase;
  • a second B alloy layer is laminated and bonded to the first surface of the raw material base layer, and the second B alloy layer contains (M, ⁇ Mn) phase;
  • the multi-phase alloy contains ⁇ Mn phase and (M, ⁇ Mn) phase to obtain the first A multi-layer body of raw materials.
  • the method for preparing a conductive film of the present application also includes the step of preparing a first raw material multilayer body, specifically including:
  • a raw material base layer which includes a main body layer and a first conductive adhesive layer stacked on one side surface of the main body layer, and optionally, also includes a third conductive adhesive layer stacked on the other side surface of the main body layer.
  • the temperature of the split-phase heat treatment is 500-700°C.
  • the time of the split-phase heat treatment is 1-4 hours.
  • the phase-separated heat treatment is followed by cooling at a cooling rate of 20-1000°C/s.
  • the present application provides a current collector, including the conductive film described in any one of the above.
  • the present application provides a secondary battery, including the current collector described in any one of the above;
  • the secondary battery is a negative electrode-less metal battery
  • the negative active material of the secondary battery contains a metal or alloy.
  • the present application provides a device, including the secondary battery according to any one of the above, and the secondary battery provides electrical energy to the device.
  • the conductive film has a laminated structure of a base layer and a porous layer.
  • the base layer has good tensile strength, which provides good support for the porous layer and also improves the overall tensile strength of the conductive film.
  • the porous conductive material has pores with a first pore size and pores with a second pore size.
  • the inner wall of the hole with the first pore diameter (referred to as macropore) can serve as a substrate for active material deposition; in addition, another function of the macropore is to provide an electrolyte infiltration channel.
  • the inner wall of the hole with the second pore diameter (referred to as the small hole) can serve as a base for active material deposition.
  • the small pores increase the specific surface area of the material, allowing the porous conductive material to load more active materials; in addition, another role of the small pores is to serve as a template for the deposition of active materials.
  • the active material deposited in the pores has a nanoscale size.
  • the nanoscale active material has a high ionic conductivity due to its small size, which can improve the overall ionic conductivity of the electrode. rate, thereby improving the rate performance of the battery, and ultimately improving the capacity, cycle stability and rate performance of the battery as a whole; in addition, another function of the small holes is to limit the volume expansion of the active material and avoid its pulverization failure.
  • the Mn-Cu binary alloy (Mn content 60-90at.%) has a (M, ⁇ Mn) single-phase structure in the temperature range of 700-865°C, while in the temperature range of 500-700°C It is an ⁇ / ⁇ dual-phase structure. Therefore, the Mn-Cu alloy prepared by smelting can be annealed at high temperature (700-865°C) to obtain a (M, ⁇ Mn) single-phase alloy with excellent plastic processing ability, and precursor alloys of different shapes can be prepared. This is followed by low-temperature (500-700°C) aging treatment to form an ⁇ / ⁇ dual-phase structure, which is used to prepare the final porous conductive material.
  • the composition of the second A alloy layer/second B alloy layer is mainly (M, ⁇ Mn) phase, which has good plasticity and can be processed by plastic processing methods (forging, rolling). (making, drawing, etc.) to process them into processed products of different shapes and sizes. Subsequent phase separation heat treatment and dealloying operations on the processed product will basically not change the shape and size of the processed product.
  • the method of the present application can obtain a product after dealloying that can maintain the shape and size of the parent body, and can prepare a large-sized conductive film.
  • the method of the present application can flexibly adjust the pore diameter and proportion of the pores with the second pore diameter and the pores with the first pore diameter in the porous conductive material. For example, by adjusting the temperature and time of the phase separation heat treatment, the content and size of the ⁇ Mn phase in the second product can be controlled, and thereby the content and pore size of the pores with the first pore size in the porous conductive material can be controlled. For another example, by adjusting the dealloying corrosion temperature, the content and pore diameter of the pores with the second pore diameter in the porous conductive material can be controlled.
  • Figure 1 shows a schematic diagram and a partial enlarged view of a conductive film according to some embodiments of the present application.
  • Figure 2 shows a schematic diagram and a cross-sectional scanning electron microscope photograph of a conductive film according to some embodiments of the present application.
  • FIG. 3 shows a scanning electron microscope photograph of the first porous layer of the conductive film in Example 1 of the present application.
  • Figure 4 shows a scanning electron microscope photograph of the first porous layer of the conductive film in Example 2 of the present application.
  • Figure 5 shows a scanning electron microscope photograph of the first porous layer of the conductive film in Example 3 of the present application.
  • Figure 6 is a binary phase diagram of Mn-Cu alloy.
  • Figure 7 (a) is the XRD pattern of the second A alloy layer in some embodiments of the present application
  • Figure 7 (b) is the XRD pattern of the first A alloy layer in some embodiments of the present application
  • Figure 7 (c) These are XRD patterns of the first porous layer in some embodiments of the present application.
  • Example 8 is a cycle number-capacity curve of a secondary battery containing the conductive films of Example 2 and Comparative Example 2.
  • FIG. 9 is an overall view and an exploded view of a secondary battery according to an embodiment of the present application.
  • FIG. 10 is a schematic diagram of a battery module according to an embodiment of the present application.
  • Figure 11 is a schematic diagram of a battery pack according to an embodiment of the present application.
  • FIG. 12 is an exploded view of the battery pack according to one embodiment of the present application shown in FIG. 11 .
  • FIG. 13 is a schematic diagram of a device using a secondary battery as a power source according to an embodiment of the present application.
  • Figure 14 shows a schematic diagram of a conductive film in some embodiments of the present application.
  • Figure 15 shows a schematic diagram of a conductive film according to some embodiments of the present application.
  • Ranges disclosed herein are defined in terms of lower and upper limits. A given range is defined by selecting a lower limit and an upper limit that define the boundaries of the particular range. Ranges defined in this manner may be inclusive or exclusive of the endpoints, and may be arbitrarily combined, that is, any lower limit may be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a particular parameter, understand that ranges of 60-110 and 80-120 are also expected. Furthermore, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2- 3, 2-4 and 2-5.
  • the numerical range “a-b” represents an abbreviated representation of any combination of real numbers between a and b, where a and b are both real numbers.
  • the numerical range “0-5" means that all real numbers between "0-5" have been listed in this article, and "0-5" is just an abbreviation of these numerical combinations.
  • a certain parameter is an integer ⁇ 2
  • a method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially.
  • step (c) means that step (c) can be added to the method in any order.
  • the method may include steps (a), (b) and (c), and may also include step (a). , (c) and (b), and may also include steps (c), (a) and (b), etc.
  • condition "A or B” is satisfied by any of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists) ; Or both A and B are true (or exist).
  • the porous layer refers to the first porous layer, the second porous layer, or a combination thereof.
  • the first porous layer and the second porous layer may have the same or different materials, the same or different compositions, the same or different pore size distribution characteristics, the same or different sizes, and the same or different thicknesses. .
  • the present application provides a conductive film
  • the conductive film includes:
  • the base layer has a first surface and a second surface arranged oppositely, and the base layer has a dense structure
  • a first porous layer, the first porous layer is laminated and bonded to the first surface of the base layer;
  • the first porous layer includes a porous conductive material
  • the porous conductive material has pores of a first pore size and pores of a second pore size
  • the first pore diameter is n microns, 0.5 ⁇ n ⁇ 10;
  • the second pore diameter is m nanometers, 20 ⁇ m ⁇ 200.
  • the conductive film of the above solution has a base layer and a porous layer that are laminated and combined. Among them, the porous layer has relatively weak mechanical strength due to its porous structure.
  • a base layer with good tensile properties (for example, a tensile strength of 330 N/mm or above) is combined with a porous layer to obtain a multi-layer conductive film.
  • the conductive film has both enhanced mechanical properties and porous structure and is suitable for use as a secondary battery. Current collector.
  • the term "laminated bonding” means that the base layer and the porous layer are bonded by chemical bonds (eg, metal bonds) at positions where they are layered on top of each other.
  • the bonding strength between the base layer and the porous layer can be tested through the tape peeling test, where the tape is bonded to the surface of the porous layer and then peeled off.
  • the bonding strength between the base layer and the porous layer can resist tape peeling with a ⁇ 180° of more than 7N/mm, while the porous layer will not fall off.
  • the term "conductive film” means that the conductivity in the plane direction or thickness direction of the film is 103 (Siemens/cm) or more, such as 10 5 (Siemens/cm) or more, such as 10 7 (Siemens/cm) or more. cm) or more.
  • the base layer has a dense structure, and the porosity of the base layer is, for example, zero.
  • the conductive film of the above solution contains porous conductive materials, and the porous conductive materials have innovative multi-level pore size distribution characteristics.
  • the new porous conductive material is particularly suitable for use in anode-free metal batteries (such as anode-free lithium metal batteries or anode-free sodium metal batteries) or batteries containing active metal/alloy anodes.
  • the inner wall of the hole with the first pore diameter (referred to as macropore) can serve as a substrate for active material deposition; in addition, another function of the macropore is to provide an electrolyte infiltration channel.
  • the inner wall of the hole with the second pore diameter (referred to as the small hole) can serve as a base for active material deposition.
  • the small pores increase the specific surface area of the material, allowing the porous conductive material to load more active materials; in addition, another role of the small pores is to serve as a template for the deposition of active materials.
  • the active material deposited in the pores has a nanoscale size.
  • the nanoscale active material has a high ionic conductivity due to its small size, which can improve the overall ionic conductivity of the electrode. rate, thereby improving the rate performance of the battery, and ultimately improving the capacity, cycle stability and rate performance of the battery as a whole; in addition, another function of the small holes is to limit the volume expansion of the active material and avoid its pulverization failure.
  • FIG. 1 shows a schematic diagram of a conductive film according to an embodiment.
  • the conductive film includes: a base layer 100 and a first porous layer 110 .
  • the base layer 100 has a first surface 101 and a second surface 102 arranged oppositely, and the base layer 100 has a tensile strength of more than 100 MPa; the first porous layer 110 is laminated and bonded to the first surface 101 of the base layer 110; the first porous layer 110
  • the material is porous conductive material.
  • the dotted frame on the first porous layer 110 leads to a partial enlarged schematic diagram of the porous conductive material 60 .
  • the porous conductive material 60 has a macroporous structure.
  • the macroporous structure has pores 601 with a first pore diameter, and adjacent pores 601 with the first pore diameter are separated by first ribs 600 .
  • the dotted frame on the first rib 600 leads to a partial enlarged schematic diagram of the first rib 600 .
  • the first rib 600 has a small hole structure, and the small hole structure has holes 602 of a second diameter, and adjacent holes 602 of the second diameter are separated by a second rib 604 .
  • the porous conductive material based on the above scheme has innovative multi-level pore size distribution characteristics.
  • the new porous conductive material is particularly suitable for use in anode-free metal batteries (such as anode-free lithium metal batteries or anode-free sodium metal batteries) or metal or alloy anode batteries.
  • the inner wall of the hole with the first pore diameter (referred to as macropore) can serve as a substrate for active material deposition; in addition, another function of the macropore is to provide an electrolyte infiltration channel.
  • the inner wall of the hole with the second pore diameter (referred to as the small hole) can serve as a base for active material deposition.
  • the small pores increase the specific surface area of the material, allowing the porous conductive material to load more active materials; in addition, another role of the small pores is to serve as a template for the deposition of active materials.
  • the active material deposited in the pores has a nanoscale size.
  • the nanoscale active material has a high ionic conductivity due to its small size, which can improve the overall ionic conductivity of the electrode. rate, thereby improving the rate performance of the battery, and ultimately improving the capacity, cycle stability and rate performance of the battery as a whole; in addition, another function of the small holes is to limit the volume expansion of the active material and avoid its pulverization failure.
  • the first pore diameter is n microns, 0.5 ⁇ n ⁇ 10; the value of n can be 0.5-1, 1-2, 2-3, 3-4, 4-5, 5-6, 6- 7. 7-8, 8-9 or 9-10.
  • n can be 0.5-1, 1-2, 2-3, 3-4, 4-5, 5-6, 6- 7. 7-8, 8-9 or 9-10.
  • 0.5 ⁇ m-10 ⁇ m micron pores have better battery capacity, cycle stability and rate performance ( Reducing the particle size of the active material can improve the ionic conductivity of the electrode material, thereby improving the overall conductivity of the electrode and improving the rate performance of the battery).
  • the specific surface area of the metal current collector can be further increased, thereby enabling Load more active substances.
  • the second pore diameter is m nanometers, 20 ⁇ m ⁇ 200; the value of m can be 20-40, 40-60, 60-80, 80-100, 100-120, 120-140, 140 -160, 160-180 or 180-200.
  • Figure 2 shows a schematic diagram of a conductive film according to some embodiments of the present application.
  • the conductive film further includes a second porous layer 120 , and the second porous layer 120 is laminated and bonded to the second surface 102 of the base layer 100 .
  • the first porous layer 110 and the second porous layer 120 each independently include a porous conductive material; the porous conductive material has pores of a first pore diameter and pores of a second pore diameter; the first pore diameter is n microns, 0.5 ⁇ n ⁇ 10; The second pore diameter is m nanometers, 20 ⁇ m ⁇ 200.
  • the conductive film based on this solution has porous layers on both sides of its surface. Both sides of the conductive film can be used as collecting surfaces for active materials.
  • the conductive film is used in secondary batteries.
  • the secondary batteries show improved capacity and cycle stability. performance and/or rate performance.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the value of V 1 /V is 5%-15%, 10%-15%, 15%-20%, 20%-30%, 30%-40%, 40%-50%, 50 %-60% or 60%-70%.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the apparent volume of the porous conductive material is V
  • the total pore volume of the pores having the second pore diameter is V 2
  • the value of V2 /V is 15%-20%, 20%-30%, 30%-40%, 40%-50%, 50%-60%, or 60%-70%.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • adjacent pores with the first pore diameter are separated by first ribs, and the average rib diameter of the first ribs is 0.89 ⁇ m-3 ⁇ m (for example, 1 ⁇ m-1.5 ⁇ m, 1.5 ⁇ m-2 ⁇ m, 2 ⁇ m -2.5 ⁇ m, 2.5 ⁇ m-3 ⁇ m).
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • adjacent pores with a second pore diameter are separated by second ribs, and the average edge diameter of the second ribs is 27nm-100nm (for example, 30nm-40nm, 40nm-50nm, 50nm-60nm, 60nm-70nm, 70nm-80nm, 80nm-90nm or 90nm-100nm).
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the total specific surface area of the pores having the first pore diameter is 0.08m 2 /g-1.32m 2 /g (eg, 0.1m 2 /g-0.3m 2 /g, 0.3m 2 /g-0.5m 2 /g 2 /g, 0.5m 2 /g-0.7m 2 /g, 0.7m 2 /g-0.9m 2 /g , 0.9m 2 /g-1.1m 2 /g, 1.1m 2 /g-1.3m 2 / g).
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the total specific surface area of the pores with the second pore diameter is 0.87m 2 /g-5.25m 2 /g (eg, 1m 2 /g-1.5m 2 / g, 1.5m 2 /g-2m 2 / g ⁇ 2m 2 /g-2.5m 2 /g ⁇ 2.5m 2 /g-3m 2 /g ⁇ 3m 2 /g-3.5m 2 /g ⁇ 3.5m 2 /g-4m 2 /g ⁇ 4m 2 /g -4.5m 2 /g, 4.5m 2 /g-5m 2 /g).
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the porous conductive material has a specific surface area of 0.95m 2 /g-6.57m 2 /g (eg, 1m 2 /g-1.5m 2 /g, 1.5m 2 /g-2m 2 /g, 2m 2 /g-2.5m 2 /g ⁇ 2.5m 2 /g-3m 2 /g ⁇ 3m 2 /g-3.5m 2 /g ⁇ 3.5m 2 /g-4m 2 /g ⁇ 4m 2 /g-4.5m 2 /g, 4.5m 2 /g-5m 2 /g, 5m 2 /g-5.5m 2 /g, 5.5m 2 /g-6m 2 /g).
  • 0.95m 2 /g-6.57m 2 /g eg, 1m 2 /g-1.5m 2 /g, 1.5m 2 /g-2m 2 /g, 2m 2 /g-2.5m 2 /g ⁇ 2.5m 2 /g-3m 2 /g ⁇ 3m 2 /g-3.5m 2
  • the specific surface area of the porous conductive material may, for example, be equal to the sum of the total specific surface area of the pores having the first pore diameter and the total specific surface area of the pores having the second pore diameter.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the base layer has a thickness of 4.5 ⁇ m-12 ⁇ m, such as 4.5 ⁇ m-6 ⁇ m, 6 ⁇ m-8 ⁇ m, 8 ⁇ m-10 ⁇ m, 10 ⁇ m-12 ⁇ m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the first porous layer has a thickness of 50 ⁇ m-200 ⁇ m, such as 50 ⁇ m-100 ⁇ m, 100 ⁇ m-150 ⁇ m, 150 ⁇ m-200 ⁇ m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the thickness of the second porous layer is 50 ⁇ m-200 ⁇ m, such as 50 ⁇ m-100 ⁇ m, 100 ⁇ m-150 ⁇ m, 150 ⁇ m-200 ⁇ m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the conductive film has a total thickness of 50 ⁇ m to 450 ⁇ m.
  • the total thickness of the conductive film may be, for example, 50 ⁇ m to 100 ⁇ m, 100 ⁇ m to 150 ⁇ m, 150 ⁇ m to 200 ⁇ m, 200 ⁇ m to 250 ⁇ m, 250 ⁇ m to 300 ⁇ m, 300 ⁇ m to 350 ⁇ m, 350 ⁇ m to 400 ⁇ m, or 400 ⁇ m to 450 ⁇ m.
  • the porous conductive material is made of a metal element or alloy containing M element, and the M element is selected from copper, aluminum or a combination thereof.
  • the porous conductive material is made of copper or copper alloy.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the porous conductive material is prepared using a dealloying method.
  • the porous conductive material is gas and/or liquid permeable.
  • the base layer has a tensile strength of greater than 330 N/m.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the conductive film has a tensile strength of greater than 100 N/mm.
  • the conductive film based on this scheme has satisfactory strength, and is used in secondary batteries that exhibit improved capacity, cycle stability, and/or rate performance.
  • the base layer has, for example, a tensile strength of 330 N/mm 2 to 500 N/mm 2 , for example, has a tensile strength of 330 N/mm 2 to 400 N/mm 2 , for example, has a tensile strength of 400 N/mm 2 to 450 N/mm 2 , for example, has a tensile strength of 450N/mm 2 to 500N/mm 2 .
  • the conductive film for example, has a tensile strength of 330 N/mm 2 to 500 N/mm 2 , for example, has a tensile strength of 330 N/mm 2 to 400 N/mm 2 , for example, has a tensile strength of 400 N/mm 2 to 450 N/mm 2 , for example, has a tensile strength of 450N/mm 2 to 500N/mm 2 .
  • the base layer has a single-layer structure or a multi-layer structure.
  • the base layer 100 has a single-layer structure or a multi-layer structure, for example, the base layer may have a two-layer structure or a three-layer structure.
  • the base layer 100 has a multi-layer structure, by specifically designing the materials of each layer of the base layer 100, a base layer with better overall performance can be obtained.
  • a dense metal material layer is provided in the base layer so that the base layer has higher tensile strength.
  • one or more conductive adhesive layers are provided in the base layer so that the base layer can be easily and firmly laminated with the porous layer.
  • Figure 14 shows a schematic diagram of a conductive film in some embodiments of the present application.
  • the base layer 100 has a multi-layer structure.
  • the base layer 100 includes a main body layer 1005 and a first conductive adhesive layer 1001 laminated on one side surface of the main body layer 1005.
  • the first conductive adhesive layer 1001 has a multi-layer structure.
  • the surface of the glue layer 1001 facing away from the main body layer 1005 constitutes the first surface 101 of the base layer 100 .
  • Figure 15 shows a schematic diagram of a conductive film according to some embodiments of the present application.
  • the base layer 100 has a multi-layer structure.
  • the base layer 100 includes a main body layer 1005 and a first conductive adhesive layer 1001 and a second conductive adhesive layer respectively laminated on opposite sides of the main body layer 1005.
  • Glue layer 1002 the surface of the first conductive glue layer 1001 facing away from the main body layer 1005 constitutes the first surface 101 of the base layer, and the surface of the second conductive glue layer 1002 facing away from the main body layer 1005 constitutes the the second surface 102 of the base layer.
  • the thickness ratio of the main body layer 1005 to the first conductive adhesive layer 1001 is 4.5-12:1-10, such as 4.5-8:2, such as 5-7:2.
  • the thickness ratio of the main body layer 1005 to the second conductive adhesive layer 1002 is 4.5-12:1-10, such as 4.5-8:2, such as 5-7:2.
  • the conductive glue contains an adhesive component and a conductive component.
  • the adhesive component is selected from one or more of epoxy resin, silicone resin, polyimide resin, polyurethane, and acrylic resin.
  • the conductive component is selected from one or more of carbon materials (such as carbon nanotubes) and metal materials (such as Au, Ag, Cu, Ni).
  • the conductivity of the conductive adhesive is, for example, 1.1 ⁇ 10 -10 Siemens/meter (S/m) or above.
  • this application provides a method for preparing a conductive film.
  • the definition of the conductive film is as described in any of the above embodiments.
  • the preparation method includes:
  • the first raw material multilayer body includes:
  • the raw material base layer has a first surface and a second surface arranged oppositely, and the raw material base layer has a dense structure
  • the first A alloy layer is laminated and bonded to the first surface of the raw material base layer.
  • the material of the first A alloy layer is a multi-phase alloy.
  • the multi-phase alloy contains ⁇ Mn phase and (M, ⁇ Mn) phase.
  • the M element is selected From copper, aluminum or combinations thereof;
  • the first B alloy layer is laminated and bonded to the second surface of the raw material base layer.
  • the material of the first B alloy layer is a multi-phase alloy, and the multi-phase alloy contains ⁇ Mn phase and (M, ⁇ Mn) phase.
  • the M element is selected from copper, aluminum or a combination thereof;
  • the raw material base layer is configured to remain intact during the dealloying process.
  • the raw material base layer does not undergo dealloying reaction during the dealloying process.
  • the material of the base layer can be a relatively inactive metal, for example, a metal with a standard electrode potential greater than zero, such as Cu, Ni, Ag, Pt, Au, or alloys thereof.
  • the above method cleverly utilizes the different chemical reactions of the ⁇ Mn phase and (M, ⁇ Mn) phase in the multiphase alloy during the dealloying process.
  • the ⁇ Mn phase is removed during the dealloying process to form a pore with a first pore diameter
  • (M, ⁇ Mn) phase is removed during the dealloying process to form pores with a second pore size, thereby obtaining a conductive film with a novel porous structure of the present application.
  • the Mn-Cu binary alloy (Mn content 90-60at.%) has a (M, ⁇ Mn) single-phase structure in the temperature range of 700-865°C, while in the temperature range of 500-700°C It is an ⁇ / ⁇ dual-phase structure. Therefore, the Mn-Cu alloy prepared by smelting can be annealed at high temperature (700-865°C) to obtain a (M, ⁇ Mn) single-phase alloy with excellent plastic processing ability, and precursor alloys of different shapes can be prepared. This is followed by low-temperature (500-700°C) aging treatment to form an ⁇ / ⁇ dual-phase structure, which is used to prepare the final porous conductive material.
  • ⁇ Mn is an allotrope of manganese with a cbcc structure.
  • the (M, ⁇ Mn) phase is a solid solution phase formed by dissolving element M in ⁇ Mn.
  • the (Cu, ⁇ Mn) phase is a solid solution phase formed by the element Cu dissolved in ⁇ Mn.
  • a solid solution is a single-phase crystalline solid formed by dissolving one or more solute components into a crystalline solvent and retaining the solvent's crystal lattice type.
  • dealloying is used to remove at least 90 at.% of the Mn elements from the ⁇ Mn phase. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • dealloying is used to remove at least 90 at.% of the Mn elements from the (M, ⁇ Mn) phase. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the amount of M elements removed by the dealloying method is less than 10 at.%. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the content of Mn element in the ⁇ Mn phase is >99 at.%. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the content of Mn element in the (M, ⁇ Mn) phase is 40-80 at.%. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the (M, ⁇ Mn) phase is a solid solution. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the content of the ⁇ Mn phase in the multiphase alloy ranges from 22 to 70 vol%. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the content of ⁇ Mn phase in the multiphase alloy is 22-70vol%, such as 22-30vol%, 30-40vol%, 40-50vol%, 50-60vol%, 60-70vol%, (M, ⁇ Mn The content of the ) phase is 30-78vol%, for example, 30-40vol%, 40-50vol%, 50-60vol%, 60-78vol%.
  • the content of the (M, ⁇ Mn) phase in the multiphase alloy is 30-78 vol%. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the ⁇ Mn phase and the (M, ⁇ Mn) phase are uniformly dispersed in the multiphase alloy. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the multiphase alloy contains Mn element and M element, the content of Mn element is 60%-90at.%, the content of M element is 10-40at.%, and the M element is selected from copper, aluminum or a combination thereof. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the dealloying process is mainly based on the difference in standard electrochemical potential of the precursor components to selectively remove relatively active elements in the system, and the remaining metal atoms are connected to each other to obtain a porous conductive material.
  • the method of dealloying is selected from chemical etching, electrochemical etching, or a combination thereof. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the method for preparing a conductive film of the present application also includes the step of preparing a first raw material multilayer body, specifically including:
  • the second raw material multilayer body includes:
  • the raw material base layer has a first surface and a second surface arranged oppositely, and the raw material base layer has a dense structure
  • the second A alloy layer is laminated and bonded to the first surface of the raw material base layer, and the content of the (M, ⁇ Mn) phase in the second A alloy layer is more than 95 vol%;
  • the second B alloy layer is laminated and bonded to the first surface of the raw material base layer, and the content of the (M, ⁇ Mn) phase in the second B alloy layer is more than 95 vol%;
  • the multi-phase alloy contains ⁇ Mn phase and (M, ⁇ Mn) phase to obtain the first raw material Multi-layered body.
  • the method for preparing a conductive film of the present application also includes the step of preparing a first raw material multilayer body, specifically including:
  • a raw material base layer which includes a main body layer and a first conductive adhesive layer stacked on one side surface of the main body layer, and optionally, also includes a third conductive adhesive layer stacked on the other side surface of the main body layer.
  • the second A alloy layer/second B alloy layer containing the (M, ⁇ Mn) phase has excellent room temperature plasticity.
  • plastic processing methods such as forging, rolling, and drawing, processed products of different shapes and sizes can be obtained.
  • the processed product can maintain shape and size stability during subsequent heat treatment and dealloying processes.
  • the second raw material multilayer body is prepared by a stack rolling method, such as a stack hot rolling method.
  • (M, ⁇ Mn) phase alloy foil and copper foil can be laminated in the required order and then hot rolled to obtain a second raw material multilayer body.
  • the temperature of the split-phase heat treatment is 500-700°C.
  • the duration of the split-phase heat treatment is 1-4 hours.
  • the phase split heat treatment is followed by cooling at a cooling rate of 20-1000°C/s.
  • the material of the second A alloy layer and/or the second A alloy layer is copper-manganese alloy, and the content of Mn element is 60%-90%.
  • a ⁇ single-phase alloy with a (M, ⁇ Mn) phase content of 95 vol% or more can be obtained by subjecting a copper-manganese alloy to a first heat treatment.
  • the temperature of the first heat treatment is 700-865°C. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the time of the first heat treatment is more than 0.16 hours, such as 1-2 hours. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • a cooling rate of 20-1000°C/s is used for cooling, such as water cooling. Based on this, the obtained porous conductive material has innovative pore distribution characteristics.
  • the method further includes the operation of plastically processing the first product prior to performing the phase separation heat treatment.
  • the phase separation heat treatment is configured to convert a portion of the (M, ⁇ Mn) phase into the ⁇ Mn phase.
  • the raw material base layer has a tensile strength of 330 N/mm 2 or more (for example, the base layer has a tensile strength of 330 N/mm 2 to 500 N/mm 2 , for example, the base layer has a tensile strength of 330 N/mm 2 to 400 N/mm 2 Strength, such as a tensile strength of 400N/mm 2 to 500N/mm 2 )
  • the present application provides a current collector including any one of the above porous conductive materials.
  • the present application provides a secondary battery including any of the above current collectors
  • the secondary battery is a negative electrode-less metal battery
  • the negative active material of the secondary battery contains a metal or alloy.
  • the present application provides a device, including any of the above-mentioned secondary batteries, and the secondary battery provides electrical energy to the device.
  • Secondary batteries also known as rechargeable batteries or storage batteries, refer to batteries that can be recharged to activate active materials and continue to be used after the battery is discharged.
  • a secondary battery normally includes a positive electrode plate, a negative electrode plate, a separator and an electrolyte.
  • active ions such as lithium ions
  • the isolation film is placed between the positive electrode piece and the negative electrode piece. It mainly prevents the positive and negative electrodes from short-circuiting and allows active ions to pass through.
  • the electrolyte is between the positive electrode piece and the negative electrode piece and mainly plays the role of conducting active ions.
  • the positive electrode sheet usually includes a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector.
  • the positive electrode film layer includes a positive electrode active material.
  • a surface treatment composition may be disposed between the positive electrode current collector and the positive electrode film layer.
  • the positive electrode current collector has two surfaces facing each other in its own thickness direction, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.
  • the positive electrode current collector may contain any of the above-mentioned porous conductive materials of the present application.
  • the positive electrode current collector can also be a composite current collector.
  • it can be made by combining any of the above porous conductive materials with a polymer material substrate (such as polypropylene (PP), polyethylene terephthalate (PET), poly It is formed by compounding base materials such as butylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.
  • PP polypropylene
  • PET polyethylene terephthalate
  • PS polystyrene
  • PE polyethylene
  • the cathode active material may be a cathode active material known in the art for batteries.
  • the cathode active material may include at least one of the following materials: an olivine-structured lithium-containing phosphate, a lithium transition metal oxide, and their respective modified compounds.
  • the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials of batteries can also be used. Only one type of these positive electrode active materials may be used alone, or two or more types may be used in combination.
  • lithium transition metal oxides may include, but are not limited to, lithium cobalt oxides (such as LiCoO 2 ), lithium nickel oxides (such as LiNiO 2 ), lithium manganese oxides (such as LiMnO 2 , LiMn 2 O 4 ), lithium Nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1/3 Co 1/3 Mn 1/3 O 2 (also referred to as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O 2 (can also be abbreviated to NCM523), LiNi 0.5 Co 0.25 Mn 0.25 O 2 (can also be abbreviated to NCM211), LiNi 0.6 Co 0.2 Mn 0.2 O 2 (can also be abbreviated to NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O 2 (also referred to as NCM811), at least one of lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15),
  • lithium-containing phosphates with an olivine structure can include but are not limited to lithium iron phosphate (such as LiFePO 4 (also referred to as LFP)), composite materials of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO 4 ), composite materials of lithium manganese phosphate and carbon, manganese phosphate At least one composite material of lithium iron, lithium iron manganese phosphate and carbon.
  • lithium iron phosphate such as LiFePO 4 (also referred to as LFP)
  • composite materials of lithium iron phosphate and carbon such as LiMnPO 4
  • LiMnPO 4 lithium manganese phosphate
  • manganese phosphate At least one composite material of lithium iron, lithium iron manganese phosphate and carbon.
  • the positive electrode film layer optionally further includes surface treatment.
  • surface treatments may include polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer At least one of copolymer, tetrafluoroethylene-hexafluoropropylene copolymer and fluorine-containing acrylate resin.
  • the positive electrode film layer optionally further includes a conductive agent.
  • the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.
  • the positive electrode sheet can be prepared by dispersing the above-mentioned components for preparing the positive electrode sheet, such as positive active material, conductive agent, surface treatment and any other components in a solvent (such as N- Methylpyrrolidone) to form a positive electrode slurry; the positive electrode slurry is coated on the positive electrode current collector, and after drying, cold pressing and other processes, the positive electrode piece can be obtained.
  • a solvent such as N- Methylpyrrolidone
  • the conductive film of the present application can be directly used as the negative side current collector (or electrode) of anode-free metal batteries (such as anode-free lithium metal batteries or anode-free sodium metal batteries).
  • anode-free metal batteries such as anode-free lithium metal batteries or anode-free sodium metal batteries.
  • lithium-free negative electrode battery In a lithium-free negative electrode battery, all active lithium ions are initially stored in the positive electrode material. During the initial charging process, lithium ions are extracted from the positive electrode, moved to the negative electrode, and directly plated in situ on the negative electrode bare current collector to form lithium metal. negative electrode. Subsequently, during the discharge process, active lithium ions are stripped from the lithium metal negative electrode formed in situ and embedded into the positive electrode. Lithium-free negative electrode batteries are small in size and have greater energy density.
  • porous conductive material of the present application can also be used as the negative electrode side current collector of batteries containing active metal/alloy negative electrodes.
  • the active metal/alloy is, for example, lithium metal or lithium alloy.
  • the negative electrode sheet of a lithium metal battery uses the porous conductive material of the present application as the negative electrode current collector, and a lithium metal layer is deposited on the outer surface and/or inside the pores of the porous conductive material.
  • lithium alloy as used herein is intended to mean a substance capable of forming an alloy with lithium upon charging and capable of reversibly adsorbing and releasing lithium.
  • substances capable of forming an alloy with lithium include substances such as tin (Sn), silicon (Si), zinc (Zn), aluminum (Al), magnesium (Mg), indium (In), cadmium (Cd), lead (Pb) , bismuth (Bi) and antimony (Sb) metal elements and their compounds and their alloys (including alloys of lithium and these elemental metals).
  • other active metals/alloys besides lithium metal or lithium alloys include, for example, tin (Sn), silicon (Si), zinc (Zn), aluminum (Al), magnesium (Mg), indium (In ), cadmium (Cd), lead (Pb), bismuth (Bi) and antimony (Sb) metal elements and their compounds and alloys thereof (including alloys of lithium and these elemental metals).
  • methods such as electrodeposition, vapor deposition (such as physical/chemical vapor deposition), magnetron sputtering, etc. can be used to deposit active metals/alloys on the surface and inside the voids of the porous conductive material to obtain the battery negative electrode.
  • the electrolyte plays a role in conducting ions between the positive and negative electrodes.
  • the type of electrolyte in this application can be selected according to needs.
  • the electrolyte can be liquid, gel, or completely solid.
  • the electrolyte is liquid and includes an electrolyte salt and a solvent.
  • the electrolyte salt may be selected from the group consisting of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonimide, lithium bistrifluoromethanesulfonimide, trifluoromethane At least one of lithium sulfonate, lithium difluorophosphate, lithium difluoroborate, lithium dioxaloborate, lithium difluorodioxalate phosphate and lithium tetrafluoroxalate phosphate.
  • the solvent may be selected from the group consisting of ethylene carbonate, propylene carbonate, methylethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, Butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate At least one of ester, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone.
  • the electrolyte optionally also includes additives.
  • additives may include negative electrode film-forming additives, positive electrode film-forming additives, and may also include additives that can improve certain properties of the battery, such as additives that improve battery overcharge performance, additives that improve battery high-temperature or low-temperature performance, etc.
  • the secondary battery further includes a separator film.
  • a separator film There is no particular restriction on the type of isolation membrane in this application. Any well-known porous structure isolation membrane with good chemical stability and mechanical stability can be used.
  • the material of the isolation membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.
  • the isolation film can be a single-layer film or a multi-layer composite film, with no special restrictions. When the isolation film is a multi-layer composite film, the materials of each layer can be the same or different, and there is no particular limitation.
  • the positive electrode piece, the negative electrode piece and the separator film can be made into an electrode assembly through a winding process or a lamination process.
  • the secondary battery may include an outer packaging.
  • the outer packaging can be used to package the above-mentioned electrode assembly and electrolyte.
  • the outer packaging of the secondary battery may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc.
  • the outer packaging of the secondary battery may also be a soft bag, such as a bag-type soft bag.
  • the material of the soft bag may be plastic, and examples of the plastic include polypropylene, polybutylene terephthalate, polybutylene succinate, and the like.
  • FIG. 9 is an overall view and an exploded view of a square-structured secondary battery 5 as an example.
  • the outer package may include a housing 51 and a cover 53 .
  • the housing 51 may include a bottom plate and side plates connected to the bottom plate, and the bottom plate and the side plates enclose a receiving cavity.
  • the housing 51 has an opening communicating with the accommodation cavity, and the cover plate 53 can cover the opening to close the accommodation cavity.
  • the positive electrode piece, the negative electrode piece and the isolation film can be formed into the electrode assembly 52 through a winding process or a lamination process.
  • the electrode assembly 52 is packaged in the containing cavity.
  • the electrolyte soaks into the electrode assembly 52 .
  • the number of electrode assemblies 52 contained in the secondary battery 5 can be one or more, and those skilled in the art can select according to specific actual needs.
  • secondary batteries can be assembled into battery modules, and the number of secondary batteries contained in the battery module can be one or more. Those skilled in the art can select the specific number according to the application and capacity of the battery module.
  • FIG. 10 is a battery module 4 as an example.
  • a plurality of secondary batteries 5 may be arranged in sequence along the length direction of the battery module 4 .
  • the plurality of secondary batteries 5 can be fixed by fasteners.
  • the battery module 4 may further include a housing having a receiving space in which a plurality of secondary batteries 5 are received.
  • the above-mentioned battery modules can also be assembled into a battery pack.
  • the number of battery modules contained in the battery pack can be one or more. The specific number can be selected by those skilled in the art according to the application and capacity of the battery pack.
  • the battery pack 1 may include a battery box and a plurality of battery modules 4 disposed in the battery box.
  • the battery box includes an upper box 2 and a lower box 3 .
  • the upper box 2 can be covered with the lower box 3 and form a closed space for accommodating the battery module 4 .
  • Multiple battery modules 4 can be arranged in the battery box in any manner.
  • the present application also provides a device, which includes at least one of the secondary battery, battery module, or battery pack provided by the present application.
  • a secondary battery, battery module, or battery pack may be used as a power source for the device, or as an energy storage unit for the device.
  • Devices may include mobile devices (e.g., mobile phones, laptops, etc.), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, e-bikes, e-scooters, e-golf carts, e-trucks, etc. ), electric trains, ships and satellites, energy storage systems, etc., but are not limited to these.
  • a secondary battery, battery module or battery pack can be selected according to its usage requirements.
  • Figure 13 is an example device.
  • the device is a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, etc.
  • battery packs or battery modules can be used.
  • the composition of the alloy ingot is Mn 60 Cu 40 (the subscript indicates the atomic ratio).
  • the alloy ingot is forged with a forging pressure of 20t. After each forging, stress relief annealing is performed.
  • the annealing temperature is 800°C and the annealing time is 60 minutes. After annealing, it is water-cooled.
  • the forged alloy ingot is subjected to the first heat treatment.
  • the first heat treatment temperature is 800°C and the time is 60 minutes.
  • the product after the first heat treatment is a single-phase alloy composed of (Cu, ⁇ Mn) phases ( ⁇ single-phase alloy for short).
  • alloy foil and copper foil raw materials (tensile strength 370N/mm 2 ) are laminated according to the lamination method of "alloy foil/copper foil/alloy foil", and then rolled multiple times until the product reaches the target thickness and obtains the first Two raw material multilayer body.
  • the second raw material multilayer body includes: a raw material base layer, a second A alloy layer and a second B alloy layer.
  • the raw material base layer has a first surface and a second surface arranged oppositely, and the raw material base layer has a tensile strength of 370N/ mm2 ;
  • the second A alloy layer is laminated and bonded to the first surface of the raw material base layer, and the material of the second A alloy layer is ( Cu, ⁇ Mn), and the material of the second B alloy layer is (Cu, ⁇ Mn).
  • the second raw material multilayer body is subjected to phase separation heat treatment.
  • the phase separation heat treatment temperature is 650°C and the heat treatment time is 4 hours to obtain the first raw material multilayer body.
  • the second A alloy layer will be transformed into the first A alloy layer, and its material will be transformed into a polyethylene containing ⁇ Mn phase and (Cu, ⁇ Mn) phase.
  • Phase alloy the second B alloy layer will be transformed into the first B alloy layer, and its material will be transformed into a multi-phase alloy containing ⁇ Mn phase and (Cu, ⁇ Mn) phase.
  • the first raw material multilayer body includes: a raw material base layer, a first alloy layer and a second alloy layer.
  • the raw material base layer has a first surface and a second surface arranged oppositely.
  • the raw material base layer has a dense structure and a tensile strength of 370 N/mm 2 .
  • the first alloy layer is laminated and bonded to the first surface of the raw material base layer, and the material of the first alloy layer is a multi-phase alloy containing ⁇ Mn phase and (Cu, ⁇ Mn) phase.
  • the second alloy layer is laminated and bonded to the second surface of the raw material base layer, and the material of the second alloy layer is a multi-phase alloy containing ⁇ Mn phase and (Cu, ⁇ Mn) phase.
  • the first raw material multilayer body is placed in a sufficient amount of 2.38 mol/L HCl aqueous solution, and dealloying is performed by free corrosion method at a temperature of 25°C. When no obvious bubbles escape, dealloying is completed, and the conductive film of Example 1 is obtained.
  • the raw material base layer its structure and properties are basically unchanged during the dealloying process. After dealloying, its composition and tensile strength are consistent with those of the copper foil raw material.
  • the multiphase alloy containing ⁇ Mn phase and (Cu, ⁇ Mn) phase can form a porous conductive material (herein, porous copper) after dealloying treatment.
  • porous conductive material herein, porous copper
  • the (Cu, ⁇ Mn) phase in the multi-phase alloy will be partially removed, the Mn element in the (Cu, ⁇ Mn) phase will be partially removed, and the Cu element will be retained.
  • the Cu element part will form the first rib 600, and the removed Mn element part will form the hole 602 with the second pore diameter.
  • the conductive film includes: a base layer 100, a first porous layer 110 and a second porous layer 120.
  • the base layer 100 has a first surface 101 and a second surface 102 arranged oppositely.
  • the base layer 100 has a dense structure and has a tensile strength of more than 330 N/mm 2 ; the first porous layer 110 is laminated and bonded to the first surface 101 of the base layer 110;
  • the second porous layer 120 is laminated with the second surface 120 of the base layer.
  • the material of the first porous layer 110 and the second porous layer 120 is a porous conductive material (herein, porous copper).
  • the base layer 100 has a thickness of 6 ⁇ m, the first porous layer 110 has a thickness of 120 ⁇ m, and the second porous layer 120 has a thickness of 120 ⁇ m.
  • the base layer 100 is made of dense copper and has a tensile strength of 100%; the first porous layer 110 and the second porous layer 120 are both made of porous copper.
  • FIG. 3 shows a scanning electron microscope photograph of the surface of the first porous layer 101 of Example 1.
  • the first porous layer 101 is made of a porous conductive material, and the porous conductive material has pores with a first pore diameter (referred to as macropores) and pores with a second pore diameter (referred to as small pores).
  • macropores pores with a first pore diameter
  • small pores pores with a second pore diameter
  • Example 2 The difference between Example 2 and Example 1 is that the composition of the alloy ingot in step (1) is Mn 75 Cu 25 .
  • the preparation method of the conductive film of Example 2 is as follows:
  • the composition of the alloy ingot is Mn 75 Cu 25 (the subscript indicates the atomic ratio).
  • the alloy ingot is forged with a forging pressure of 20t. After each forging, stress relief annealing is performed. The annealing temperature is 800°C and the annealing time is 60 minutes. After annealing, it is water-cooled. The forged alloy ingot is subjected to a first heat treatment at a temperature of 800°C and a time of 60 minutes to obtain a single-phase alloy composed of (Cu, ⁇ Mn) phases ( ⁇ single-phase alloy for short).
  • This ⁇ single-phase alloy is subjected to preliminary hot rolling to obtain an alloy foil.
  • the alloy foil and copper foil raw materials are stacked according to the lamination method of "alloy foil/copper foil/alloy foil", and then rolled multiple times until the product reaches the target thickness, and a second raw material multilayer body is obtained.
  • the second raw material multilayer body includes: a raw material base layer, a second A alloy layer and a second B alloy layer.
  • the raw material base layer has a first surface and a second surface arranged oppositely.
  • the raw material base layer has a dense structure and has a tensile strength of 359N/ mm2 ; the second A alloy layer is laminated and bonded to the first surface of the raw material base layer, and the second A alloy layer
  • the material of is (Cu, ⁇ Mn), and the material of the second B alloy layer is (Cu, ⁇ Mn).
  • the XRD pattern of the second A alloy layer is shown in (a) of Figure 7, in which the diffraction peak of the (Cu, ⁇ Mn) phase can be observed.
  • the second raw material multilayer body is subjected to phase separation heat treatment.
  • the phase separation heat treatment temperature is 650°C and the heat treatment time is 4 hours to obtain the first raw material multilayer body.
  • the first raw material multilayer body includes: a raw material base layer, a first A alloy layer and a first B alloy layer.
  • the raw material base layer has a first surface and a first surface arranged oppositely, and the raw material base layer has a tensile strength of 359N/ mm2 ;
  • the first A alloy layer is laminated and bonded to the first surface of the raw material base layer, and the material of the first A alloy layer is Phase alloy, the material of the first B alloy layer is a multi-phase alloy.
  • the XRD pattern of the first A alloy layer is shown in Figure 7 (b). In the figure, the diffraction peak of the ⁇ Mn phase and the diffraction peak of the (Cu, ⁇ Mn) phase can be observed.
  • the first raw material multilayer body is placed in a sufficient amount of 2.38 mol/L HCl aqueous solution, and dealloying is performed by free corrosion method at a temperature of 25°C. When no obvious bubbles escape, dealloying is completed, and the conductive film of Example 2 is obtained.
  • the conductive film of Embodiment 2 includes: a base layer 100, a first porous layer 110 and a second porous layer 120.
  • the base layer 100 has a first surface 101 and a second surface 102 arranged oppositely.
  • the base layer 100 has a tensile strength of 359 N/mm 2 ; the first porous layer 110 is laminated and bonded to the first surface 101 of the base layer 110 ; the second porous layer 120 is laminated to the second surface 120 of the base layer.
  • the material of the first porous layer 110 and the second porous layer 120 is a porous conductive material (herein, porous copper).
  • the base layer 100 has a thickness of 6 ⁇ m, the first porous layer 110 has a thickness of 120 ⁇ m, and the second porous layer 120 has a thickness of 120 ⁇ m.
  • the base layer 100 is made of dense copper; the first porous layer 110 and the second porous layer 120 are both made of porous copper.
  • FIG. 4 shows a scanning electron microscope photograph of the surface of the first porous layer 101 of Example 2.
  • the first porous layer 101 is made of a porous conductive material, and the porous conductive material has pores with a first pore diameter (referred to as macropores) and pores with a second pore diameter (referred to as small pores).
  • macropores pores with a first pore diameter
  • small pores pores with a second pore diameter
  • the XRD pattern of the first porous layer is shown in (c) of Figure 7 , in which the diffraction peak of the Cu phase can be observed.
  • Example 3 The difference between Example 3 and Example 1 is that the composition of the alloy ingot in step (1) is Mn 90 Cu 10 .
  • the conductive film preparation method of Example 3 is as follows:
  • the composition of the alloy ingot is Mn 90 Cu 10 (the subscript indicates the atomic ratio).
  • the alloy ingot is forged with a forging pressure of 20t. After each forging, stress relief annealing is performed. The annealing temperature is 800°C and the annealing time is 60 minutes. After annealing, it is water-cooled. The forged alloy ingot is subjected to a first heat treatment at a temperature of 800°C and a time of 60 minutes to obtain a single-phase alloy composed of (Cu, ⁇ Mn) phases ( ⁇ single-phase alloy for short).
  • This ⁇ single-phase alloy is subjected to preliminary hot rolling to obtain an alloy foil.
  • the alloy foil and copper foil raw materials are stacked according to the lamination method of "alloy foil/copper foil/alloy foil", and then rolled multiple times until the product reaches the target thickness, and a second raw material multilayer body is obtained.
  • the second raw material multilayer body is subjected to phase separation heat treatment.
  • the phase separation heat treatment temperature is 650°C and the heat treatment time is 4 hours to obtain the first raw material multilayer body.
  • the first raw material multilayer body includes: a raw material base layer, a first A alloy layer and a first B alloy layer.
  • the raw material base layer has a first surface and a first surface arranged oppositely.
  • the raw material base layer has a dense structure and has a tensile strength of 360N/ mm2 ; the first A alloy layer is laminated and bonded to the first surface of the raw material base layer, and the first A alloy layer
  • the material of is a multi-phase alloy
  • the material of the first B alloy layer is a multi-phase alloy.
  • the first raw material multilayer body is placed in a sufficient amount of 2.38 mol/L HCl aqueous solution, and dealloying is performed by free corrosion method at a temperature of 25°C. When no obvious bubbles escape, dealloying is completed, and the conductive film of Example 2 is obtained.
  • the conductive film of Embodiment 2 includes: a base layer 100, a first porous layer 110 and a second porous layer 120.
  • the base layer 100 has a first surface 101 and a second surface 102 arranged oppositely.
  • the base layer 100 has a tensile strength of 360 N/mm 2 ; the first porous layer 110 is laminated and bonded to the first surface 101 of the base layer 110 ; the second porous layer 120 is laminated to the second surface 120 of the base layer.
  • the material of the first porous layer 110 and the second porous layer 120 is a porous conductive material (herein, porous copper).
  • the base layer 100 has a thickness of 6 ⁇ m, the first porous layer 110 has a thickness of 120 ⁇ m, and the second porous layer 120 has a thickness of 120 ⁇ m.
  • the base layer 100 is made of dense copper; the first porous layer 110 and the second porous layer 120 are both made of porous copper.
  • FIG. 5 shows a scanning electron microscope photograph of the surface of the first porous layer 101 of Example 3.
  • the first porous layer 101 is made of a porous conductive material, and the porous conductive material has pores with a first pore diameter (referred to as macropores) and pores with a second pore diameter (referred to as small pores).
  • macropores pores with a first pore diameter
  • small pores pores with a second pore diameter
  • the thickness of the first porous layer and the second porous layer is different from that in Example 2;
  • Example 10-12 The difference between Examples 10-12 and Example 2 is that the macropore diameter of the porous conductive material is different from that of Example 2. See Table 1 for details.
  • the macropore diameter is changed by adjusting the dealloying and dealloying time.
  • Example 10 the dealloying corrosion liquid is 2.2 mol/L HCl aqueous solution, the dealloying temperature is 25°C, and the dealloying time is 6 hours.
  • Example 11 the dealloying corrosion liquid is 2.38 mol/L HCl aqueous solution, the dealloying temperature is 25°C, and the dealloying time is 36 hours.
  • Example 12 the dealloying corrosion liquid is 2.38 mol/L HCl aqueous solution, the dealloying temperature is 25°C, and the dealloying time is 60 hours.
  • Example 13-15 The difference between Examples 13-15 and Example 2 is that the pore diameter of the porous conductive material is different from that in Example 2. See Table 1 for details.
  • the small hole diameter is changed by adjusting the dealloying parameters.
  • Example 13 the dealloying temperature is 25°C.
  • Example 14 the dealloying temperature was 35°C.
  • Example 15 the dealloying temperature was 40°C.
  • the composition of the alloy ingot is Mn 75 Cu 25 (the subscript indicates the atomic ratio).
  • the alloy ingot is forged with a forging pressure of 20t. After each forging, stress relief annealing is performed.
  • the annealing temperature is 800°C and the annealing time is 60 minutes. After annealing, it is water-cooled.
  • the forged alloy ingot is subjected to the first heat treatment.
  • the first heat treatment temperature is 800°C and the time is 60 minutes.
  • the product after the first heat treatment is a single-phase alloy composed of (Cu, ⁇ Mn) phases ( ⁇ single-phase alloy for short).
  • the ⁇ single-phase alloy is hot rolled to a thickness of 120um to obtain the final ⁇ single-phase alloy foil.
  • the above-mentioned ⁇ single-phase alloy foil is subjected to phase separation heat treatment.
  • the phase separation heat treatment temperature is 650°C and the heat treatment time is 4 hours to obtain a multi-phase alloy foil.
  • the Mn-Cu phase diagram shown in Figure 6 it can be known that after phase separation heat treatment, the ⁇ single-phase alloy foil with the (Cu, ⁇ Mn) phase is transformed into a multi-phase alloy foil containing the ⁇ Mn phase and the (Cu, ⁇ Mn) phase.
  • multiphase alloy foils Two multiphase alloy foils were laminated with a copper foil (tensile strength 350N/mm 2 ) coated with conductive adhesive on both sides.
  • the stacking sequence is as follows: "multiphase alloy foil/copper foil/multiphase alloy foil”. Then they are pressed to compound, and the pressing pressure is 0.3T to obtain a first raw material multilayer body.
  • the conductive glue is made of E-44 epoxy resin filled with carbon nanotubes.
  • the content of carbon nanotubes in the conductive adhesive is 2wt%, and the conductivity of the conductive adhesive is 2.1 ⁇ 10 -7 Siemens/meter (S/m).
  • the first raw material multilayer body includes: a raw material base layer, a first alloy layer and a second alloy layer.
  • the raw material base layer has a multi-layer structure (sandwich-like multi-layer structure).
  • the raw material base layer includes a main body layer (made of copper) and a first conductive adhesive layer and a second conductive adhesive layer respectively stacked on both sides of the copper main body layer.
  • the surface of the first conductive adhesive layer facing away from the copper body layer constitutes the first surface of the raw material base layer; the surface of the second conductive adhesive layer facing away from the copper body layer constitutes the second surface of the raw material base layer.
  • the raw material base layer has a dense structure and a tensile strength of 350N/ mm2 .
  • the first alloy layer is laminated and bonded to the first surface of the raw material base layer, and the material of the first alloy layer is a multi-phase alloy containing ⁇ Mn phase and (Cu, ⁇ Mn) phase.
  • the second alloy layer is laminated and bonded to the second surface of the raw material base layer, and the material of the second alloy layer is a multi-phase alloy containing ⁇ Mn phase and (Cu, ⁇ Mn) phase.
  • the first raw material multilayer body is placed in a sufficient amount of 2.38 mol/L HCl aqueous solution, and dealloying is performed by free corrosion method at a temperature of 25°C. When no obvious bubbles escape, dealloying is completed, and the conductive film of Example 16 is obtained.
  • FIG. 15 shows a schematic diagram of the conductive film of this embodiment.
  • the conductive film includes: a base layer 100 and a first porous layer 110 .
  • the base layer 100 has a first surface 101 and a second surface 102 arranged oppositely, and the base layer 100 has a tensile strength of more than 100 MPa; the first porous layer 110 is laminated and bonded to the first surface 101 of the base layer 110; the first porous layer 110 The material is porous conductive material.
  • the conductive film further includes a second porous layer 120 , and the second porous layer 120 is laminated and bonded to the second surface 102 of the base layer 100 .
  • the base layer 100 has a multi-layer structure.
  • the base layer 100 includes a main body layer 1005 and a first conductive adhesive layer 1001 and a second conductive adhesive layer 1002 respectively laminated on opposite sides of the main body layer 1005.
  • the first conductive adhesive layer The surface of 1001 facing away from the main body layer 1005 constitutes the first surface 101 of the base layer, and the surface of the second conductive adhesive layer 1002 facing away from the main body layer 1005 constitutes the second surface 102 of the base layer.
  • the thicknesses of the main body layer 1005, the first conductive adhesive layer 1001, and the second conductive adhesive layer 1002 are 6 ⁇ m, 2 ⁇ m, and 2 ⁇ m respectively.
  • the conductive film of Comparative Example 1 was composed of a single porous layer with a thickness of 200 ⁇ m. Its preparation method is as follows:
  • Mn 75 Cu 25 foil with a thickness of 200 ⁇ m whose composition is a single-phase alloy of (Cu, ⁇ Mn) phase (referred to as ⁇ single-phase alloy).
  • the conductive film in Comparative Example 2 is a commercially available single-layer copper foam with a thickness of 120 ⁇ m, a porosity of 80%, an average pore diameter of 400 ⁇ m, and a pore size distribution range of 300 ⁇ m-500 ⁇ m.
  • the total pore volume of macropores in porous copper can be reasonably derived as a percentage of the apparent volume of porous copper.
  • V 1 /V the total pore volume of small pores in porous copper accounts for the percentage of the apparent volume of porous copper
  • V 2 /V the total pore volume of macropores and small pores accounts for the percentage of the apparent volume of porous copper (( V 1 +V 2 )/V)
  • Table 1 the results are shown in Table 1.
  • the Mn-Cu alloy is fully dealloyed during the dealloying process, it can be reasonably inferred that all manganese elements in the Mn-Cu alloy are removed. After all the manganese elements in the ⁇ Mn phase of the Mn-Cu multiphase alloy are removed, the ⁇ Mn phase disappears, and a pore (referred to as macropore) structure with a first pore diameter is correspondingly formed at the position of the ⁇ Mn phase. After the manganese element in the (Cu, ⁇ Mn) phase of the Mn-Cu multiphase alloy is removed, the manganese metal in the (Cu, ⁇ Mn) phase disappears, but the copper metal is retained and formed correspondingly in the (Cu, ⁇ Mn) phase. A hole (referred to as a small hole) structure with a second pore diameter is formed.
  • the above-mentioned macroporous structure and small pore structure jointly constitute a multi-level porous structure of porous copper.
  • V 1 /V the pore volume ratio of macropores
  • V 2 /V the pore volume ratio of small pores
  • x is the Mn content (at.%) in the alloy precursor
  • x ⁇ is the Mn content (at.%) in the (Cu, ⁇ Mn) phase
  • the total specific surface area of porous copper is S (unit m 2 /g), of which the total specific surface area of large pores is S 1 and the total specific surface area of small pores is S 2 .
  • the values of the total specific surface area of macropores (S 1 ) and the total specific surface area of small pores (S 2 ) are obtained by referring to the calculation formulas and methods provided in Celal Soyarslan, et al., Acta Materialia, (2016), 149,326. .
  • the total specific surface area S S 1 +S 2 .
  • Table 3 The relevant results are shown in Table 3 below
  • C 1 is an empirical constant, and its value refers to Table 3 below;
  • ⁇ 1 is the macropore volume fraction V 1 /V. For the value, refer to Table 1;
  • L 1 is the average diameter of the ribs forming the macroporous structure
  • ⁇ Cu is the density of copper, its value is 8.9g/cm 3 ;
  • p is the atomic proportion of manganese element in the alloy
  • V is 1cm 3 .
  • C 2 is an empirical constant, and its value can be found in Table 1 below;
  • ⁇ 2 is the small pore volume fraction V 2 /V.
  • V 2 /V the small pore volume fraction
  • L 2 is the average diameter of the ribs forming the small hole structure
  • ⁇ Cu is the density of copper, its value is 8.9g/cm 3 ;
  • p is the atomic proportion of manganese element in the alloy
  • V is 1cm 3 .
  • the tensile strength of the conductive film and raw material base layer can be tested and obtained by the following methods.
  • Test method Cut the sample (the conductive film or raw material base layer to be tested) into a size of 18mm*100mm for later use. During the test, clamp both ends of the sample to the universal testing machine. On the two chucks of the machine, set the speed to 5mm/min and conduct a tensile test.
  • the formula for calculating tensile strength is as follows:
  • P b is the maximum force endured by the sample when it is pulled apart, N (Newton);
  • a 0 is the original cross-sectional area of the specimen, mm 2 ;
  • ⁇ is the tensile strength in N/mm 2 .
  • the secondary battery includes a first electrode and a second electrode arranged oppositely:
  • the first electrode uses aluminum foil as the current collector, and the surface of the current collector is coated with the positive active material lithium cobalt oxide (Dv50 is 8.1 ⁇ m).
  • the size of the first electrode is ⁇ 16mm, and the loading capacity of the active material is 0.169mg/mm 2 ;
  • the second electrode uses the conductive film mentioned in this patent, with a size of ⁇ 18mm;
  • the diaphragm is made of polyethylene isolating film with size ⁇ 20mm;
  • the electrolyte is a solution of 1 mol/L lithium hexafluorophosphate dissolved in ethylene carbonate-dimethyl carbonate (volume ratio 1:1);
  • the conductive films of Examples 1-16 have a laminated structure of a base layer and a porous layer, and the conductive films exhibit satisfactory tensile strength.
  • the base layer with good tensile strength plays the role of carrying the porous layer and provides a stable matrix for the porous layer.
  • the overall mechanical properties of the conductive film are improved, which can then play a role in secondary batteries and improve one or more multi-phase properties such as capacity, cycle performance, and rate performance of secondary batteries.
  • the conductive film in Comparative Example 1 only has a single porous layer structure, which is brittle and brittle, and its strength is too low, so that no valid data can be obtained in the tensile test.
  • the conductive film of Examples 1-16 is used as an electrode or current collector of a secondary battery, and its working principle is as follows: it has pores with a first pore size and pores with a second pore size.
  • the inner wall of the hole with the first pore diameter (referred to as macropore) can serve as a substrate for active material deposition; in addition, another function of the macropore is to provide an electrolyte infiltration channel.
  • the inner wall of the hole with the second pore diameter (referred to as the small hole) can serve as a base for active material deposition.
  • the small pores increase the specific surface area of the material, allowing the porous conductive material to load more active materials; in addition, another role of the small pores is to serve as a template for the deposition of active materials.
  • the active material deposited in the pores has a nanoscale size.
  • the nanoscale active material has a high ionic conductivity due to its small size, which can improve the overall ionic conductivity of the electrode. rate, thereby improving the rate performance of the battery, and ultimately improving the capacity, cycle stability and rate performance of the battery as a whole; in addition, another function of the small holes is to limit the volume expansion of the active material and avoid its pulverization failure.
  • the conductive film of Comparative Example 2 only has a single pore size distribution, and the pore size distribution range is 300 ⁇ m-500 ⁇ m. As shown in Table 2, the conductive films of Example 2 and Comparative Example 2 were used in secondary batteries. The secondary battery of Example 2 showed improved specific capacity (150 mAh) and cycle retention rate (87% retention after 77 cycles). ). The secondary battery of Comparative Example 2 exhibited low specific capacity (146 mAh) and cycle retention rate (77% retention after 77 cycles).

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Abstract

导电膜包括：基层（100），基层（100）具有相对设置的第一表面（101）和第二表面（102），基层（100）具有致密结构；第一多孔层（110），第一多孔层（110）层叠结合于基层（100）的第一表面（101）；第一多孔层（110）包括多孔导电材料；多孔导电材料具有第一孔径的孔（601）和第二孔径的孔（602）；第一孔径为n微米，0.5≤n≤10；第二孔径为m纳米，20<m<200。

Description

导电膜及其制备方法、电极、集流体、二次电池及装置 技术领域
本申请涉及金属材料技术领域，尤其涉及一种导电膜及其制备方法、电极、集流体、二次电池及装置。
背景技术
近年来，随着二次电池的应用范围越来越广泛，二次电池广泛应用于水力、火力、风力和太阳能电站等储能电源***，以及电动工具、电动自行车、电动摩托车、电动汽车、军事装备、航空航天等多个领域。由于二次电池取得了极大的发展，因此对其能量密度、循环性能等也提出了更高的要求。
金属锂由于其高的理论比容量(3860mAh/g)和低的电化学电位而被认为是吸引人的高能锂离子电池负极材料。然而，以金属锂为负极的电池在循环过程中会产生以下问题：产生锂枝晶、与电解液产生化学发应、沉积剥离时锂负极体积无限膨胀，这些问题必将带来电池安全隐患和低的循环效率，严重阻碍金属锂负极的实际应用。
发明内容
本申请是鉴于上述课题而进行的，其目的在于，提供一种新型的导电膜及其制备方法、电极、集流体、二次电池及装置。
本申请的新型导电膜具有层叠结合的基层和多孔层。多孔层含有创新的多孔导电材料，该多孔导电材料具有独特的多级孔径分布特征。该导电膜作为二次电池的电极或集流体使用时，多孔导电材料有利于电解液的浸润和活性物质的沉积。导电膜的基层起到支撑多孔层以及提高导电膜强度的作用。本申请的导电膜兼具良好的力学性能和电化学性能。
鉴于此，在第一方面，本申请提供一种导电膜，所述导电膜包括：
基层，所述基层具有相对设置的第一表面和第二表面，所述基层具有致密结构；
第一多孔层，所述第一多孔层层叠结合于所述基层的第一表面；
所述第一多孔层的包括多孔导电材料；
所述多孔导电材料具有第一孔径的孔和第二孔径的孔；
所述第一孔径为n微米，0.5≤n≤10；
所述第二孔径为m纳米，20＜m＜200。
上述方案的导电膜具有层叠结合的基层和多孔层。其中，多孔层由于具有多孔结构，其力学强度相对较弱。上述方案采用具有致密结构的基层与多孔层层叠结合获得力学性能增强的多孔导电膜。具有致密结构的基层具有良好的力学性能，具有独特多孔结构的多孔层用于二次电池表现出良好的电化学性能。该导电膜兼具增强的力学性能和电化学性能， 适合用作二次电池的电极/集流体。
上述方案的导电膜含有新型多孔导电材料，该多孔导电材料具有新型的多级孔径分布特征。该新型多孔导电材料特别适合用于无负极(anode free)金属电池(例如无负极锂金属电池或无负极钠金属电池)或含活性金属/合金负极的电池。具有第一孔径的孔(简称大孔)的内壁可作为活性物质沉积的基底；此外，大孔的另一个作用是提供电解液浸润通道。具有第二孔径的孔(简称小孔)的内壁可作为活性物质沉积的基底。小孔提高了材料的比表面积，从而使多孔导电材料能装载更多的活性物质；此外，小孔的另一个作用是作为活性物质沉积的模板。具体来讲，受小孔尺寸的限制，沉积在小孔中的活性物质的具有纳米级尺寸，纳米级的活性物质因尺寸小而具有较高的离子电导率，进而能够提高电极整体的离子电导率，进而能够改善电池的倍率性能，最终在整体上提高电池的容量、循环稳定性以及倍率性能；此外，小孔的另一个作用是限制活性材料的体积膨胀，避免其粉化失效。
在一些实施方案中，导电膜还包括第二多孔层，所述第二多孔层层叠结合于所述基层的第二表面；所述第一多孔层和所述第二多孔层各自独立地包括多孔导电材料；所述多孔导电材料具有第一孔径的孔和第二孔径的孔；所述第一孔径为n微米，0.5≤n≤10；所述第二孔径为m纳米，20＜m＜200。基于此方案的导电膜的两侧表面均具有多孔层，导电膜的两侧均可以作为活性物质的集流面，该导电膜用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，多孔导电材料的表观体积为V，所述具有第一孔径的孔的总孔体积V 1，所述具有第二孔径的孔的总孔体积为V 2，所述多孔导电材料满足以下关系：(V 1+V 2)/V＝60％-90％。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，多孔导电材料的表观体积为V，所述具有第一孔径的孔的总孔体积V 1，所述多孔导电材料满足以下关系：V 1/V＝5％-70％。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，所述多孔导电材料的表观体积为V，所述具有第二孔径的孔的总孔体积为V 2，所述多孔导电材料满足以下关系：V 2/V＝15％-70％。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，相邻的具有第一孔径的孔之间被第一棱丝间隔，第一棱丝的平均棱径为0.89-3μm。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，相邻的具有第二孔径的孔之间被第二棱丝间隔，第二棱丝的平均棱径为27-100nm。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，所述具有第一孔径的孔的总比表面积为0.08-1.32m 2/g。基于此方 案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，所述具有第二孔径的孔的总比表面积为0.87-5.25m 2/g。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，所述多孔导电材料的比表面积为0.95-6.57m 2/g。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，基层的厚度为4.5μm-12μm。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，第一多孔层的厚度为50-200μm。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，第二多孔层的厚度为50-200μm。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，所述多孔导电材料的材质为含有M元素的金属单质或合金，M元素选自铜、铝或其组合。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，所述基层具有330N/m 2以上的拉伸强度。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，所述导电膜具有100N/m 2以上的拉伸强度。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，材料具有致密结构是指材料的表观密度与实际密度基本相等，例如表观密度等于实际密度的90％以上，例如95％以上，例如100％。
在一些实施方案中，所述基层具有单层结构或多层结构。
在一些实施方案中，所述基层具有多层结构，所述基层包括主体层和层叠在主体层一侧表面的第一导电胶层，所述第一导电胶层背向所述主体层的表面构成所述基层的第一表面。
在一些实施方案中，所述基层具有多层结构，所述基层包括主体层和分别层叠在主体层相对两侧表面的第一导电胶层和第二导电胶层，所述第一导电胶层背向所述主体层的表面构成所述基层的第一表面，所述第二导电胶层背向所述主体层的表面构成所述基层的第二表面。
在第二方面，本申请提供一种导电膜的制备方法，所述导电膜的定义如上文任一方案 所述，所述制备方法包括：
(1)提供第一原料多层体，所述第一原料多层体包括：
原料基层，所述原料基层具有相对设置的第一表面和第二表面，原料基层具有致密结构；
第一A合金层，所述第一A合金层层叠结合于所述原料基层的第一表面，所述第一A合金层的材质为多相合金，所述多相合金含有αMn相和(M,γMn)相，M元素选自铜、铝或其组合；以及
可选地，第一B合金层，所述第一B合金层层叠结合于所述原料基层的第二表面，所述第一B合金层的材质为多相合金，所述多相合金含有αMn相和(M,γMn)相，M元素选自铜、铝或其组合；
(2)采用脱合金化的方法从所述多相合金的αMn相去除至少部分Mn元素，以及从所述多相合金的(M,γMn)相去除至少部分Mn元素；
其中，所述原料基层被配置为在所述脱合金处理的过程中保持完整。
上述方法巧妙利用了多相合金中αMn相和(M,γMn)相在脱合金过程的不同化学反应，αMn相在脱合金的过程中被脱除形成具有第一孔径的孔，(M,γMn)相中的Mn元素在脱合金的过程中被脱除形成具有第二孔径的孔，进而获得了具有本申请的具有新型多孔结构的导电膜。
在一些实施方案中，本申请制备导电膜的方法还包括制备第一原料多层体的步骤，具体包括：
(1)提供第二原料多层体，所述第二原料多层体包括：
原料基层，所述原料基层具有相对设置的第一表面和第二表面，原料基层具有致密结构；
第二A合金层，所述第二A合金层层叠结合于所述原料基层的第一表面，所述第二A合金层含有(M,γMn)相；以及
可选地，第二B合金层，所述第二B合金层层叠结合于所述原料基层的第一表面，所述第二B合金层含有(M,γMn)相；
(2)对上一步产物进行分相热处理，在第二A合金层和/或第二B合金层中形成多相合金，所述多相合金含有αMn相和(M,γMn)相，获得第一原料多层体。
在一些实施方案中，本申请制备导电膜的方法还包括制备第一原料多层体的步骤，具体包括：
(1)提供γ单相合金箔，所述γ单相合金箔中(M,γMn)相的含量为95vol％以上；
(2)对γ单相合金箔进行分相热处理，获得多相合金箔，所述多相合金箔含有αMn相和(M,γMn)相；
(3)提供原料基层，所述原料基层包括主体层和层叠在所述主体层一侧表面的第一导电胶层，以及可选地，还包括层叠在所述主体层另一侧表面的第二导电胶层；
(4)在所述第一导电胶层背向所述原料基层的表面层叠结合多相合金箔，以及可选地，在所述第二导电胶层背向所述原料基层的表面层叠结合多相合金箔。
在一些实施方案中，所述分相热处理的温度500-700℃。
在一些实施方案中，所述分相热处理的时间为1-4小时。
在一些实施方案中，所述分相热处理后采用20-1000℃/s的冷却速度进行冷却。
在第二方面，本申请提供一种集流体，包括上述任一项所述的导电膜。
在第三方面，本申请提供一种二次电池，包括上述任一项所述的集流体；
在一些实施方案中，所述二次电池是无负极金属电池；
在一些实施方案中，所述二次电池的负极活性材料含有金属或合金。
在第四方面，本申请提供一种装置，包括上述任一项所述的二次电池，所述二次电池向所述装置提供电能。
有益效果
本申请一项或多项实施方式具有以下一项或多项有益效果：
(1)导电膜具有基层与多孔层的层叠结构，基层具有良好的抗拉强度，其为多孔层提供良好的支撑，同时也改善了导电膜整体的抗拉强度。
(2)如图3-5示出的实施例的多孔导电材料的扫描电镜照片以及图1示出的多孔导电材料的示意图。本申请导电膜的多孔层中，多孔导电材料具有第一孔径的孔和第二孔径的孔。具有第一孔径的孔(简称大孔)的内壁可作为活性物质沉积的基底；此外，大孔的另一个作用是提供电解液浸润通道。具有第二孔径的孔(简称小孔)的内壁可作为活性物质沉积的基底。小孔提高了材料的比表面积，从而使多孔导电材料能装载更多的活性物质；此外，小孔的另一个作用是作为活性物质沉积的模板。具体来讲，受小孔尺寸的限制，沉积在小孔中的活性物质的具有纳米级尺寸，纳米级的活性物质因尺寸小而具有较高的离子电导率，进而能够提高电极整体的离子电导率，进而能够改善电池的倍率性能，最终在整体上提高电池的容量、循环稳定性以及倍率性能；此外，小孔的另一个作用是限制活性材料的体积膨胀，避免其粉化失效。
(3)本申请巧妙利用了多相合金的性质制备了导电膜的多孔层。根据Mn-Cu二元合金相图，Mn-Cu二元合金(Mn含量60-90at.％)在700-865℃温度区间为(M,γMn)单相结构，而在500-700℃温度区间为α/γ双相结构。因此，熔炼制备的Mn-Cu合金可以先在高温(700-865℃)退火处理，得到塑性加工能力极佳的(M,γMn)单相合金，制备出不同形状的前驱体合金。随后进行低温(500-700℃)时效处理，形成α/γ双相结构，用于制备最终 的多孔导电材料。
(4)制备多孔导电材料的方法中，第二A合金层/第二B合金层的成分主要为(M,γMn)相，其具有较好的塑性，可以通过塑性加工的方法(锻造、轧制、拉拔等)将其加工成为不同形状、尺寸的加工产物。后续再对加工产物实施分相热处理及脱合金的操作基本不会改变该加工产物的形状与尺寸。本申请的方法能够获得脱合金后的产物能够保持母体的形状尺寸，能够制备获得大尺寸的导电膜。
(5)本申请的方法能够灵活地调整多孔导电材料中的具有第二孔径的孔和具有第一孔径的孔的孔径和比例。例如，通过调整分相热处理的温度和时间，可以实现调控第二产物中的αMn相的含量与尺寸，进而实现调控多孔导电材料中具有第一孔径的孔的含量与孔径。再例如，通过调整脱合金腐蚀温度，进而实现调控多孔导电材料中具有第二孔径的孔的含量与孔径。
附图说明
图1示出本申请一些实施方式的导电膜的示意图和局部放大图。
图2示出本申请一些实施方式的导电膜的示意图和截面扫描电子显微镜照片。
图3示出本申请实施例1的导电膜的第一多孔层的扫描电子显微镜照片。
图4示出本申请实施例2的导电膜的第一多孔层的扫描电子显微镜照片。
图5示出本申请实施例3的导电膜的第一多孔层的扫描电子显微镜照片。
图6是Mn-Cu合金的二元相图。
图7的(a)为本申请一些实施例的第二A合金层的XRD图谱；图7的(b)为本申请一些实施例的第一A合金层的XRD图谱；图7的(c)为本申请一些实施例的第一多孔层的XRD图谱。
图8是含有实施例2和对比例2导电膜的二次电池的循环圈数-容量曲线。
图9是本申请一实施方式的二次电池整体图及分解图。
图10是本申请一实施方式的电池模块的示意图。
图11是本申请一实施方式的电池包的示意图。
图12是图11所示的本申请一实施方式的电池包的分解图。
图13是本申请一实施方式的二次电池用作电源的装置的示意图。
图14示出本申请又一些实施方式的导电膜的示意图。
图15示出本申请又一些实施方式的导电膜的示意图。
附图标记说明：
电池包1；上箱体2；下箱体3；电池模块4；二次电池5；壳体51；电极组件52；顶盖组件53；基层200；第一表面101；第二表面102；第一多孔层110；第二多孔层120；多孔导电材料60；具有第一孔径的孔601；第一棱丝600；具有第二孔径的孔602；第二棱丝604；主体层1005；第一导电胶层1001；第二导电胶层1002。
具体实施方式
以下，适当地参照附图详细说明具体公开了本申请的导电膜及其制备方法、电极、集流体、二次电池及装置的实施方式。但是会有省略不必要的详细说明的情况。例如，有省略对已众所周知的事项的详细说明、实际相同结构的重复说明的情况。这是为了避免以下的说明不必要地变得冗长，便于本领域技术人员的理解。此外，附图及以下说明是为了本领域技术人员充分理解本申请而提供的，并不旨在限定权利要求书所记载的主题。
本申请所公开的“范围”以下限和上限的形式来限定，给定范围是通过选定一个下限和一个上限进行限定的，选定的下限和上限限定了特别范围的边界。这种方式进行限定的范围可以是包括端值或不包括端值的，并且可以进行任意地组合，即任何下限可以与任何上限组合形成一个范围。例如，如果针对特定参数列出了60-120和80-110的范围，理解为60-110和80-120的范围也是预料到的。此外，如果列出的最小范围值1和2，和如果列出了最大范围值3，4和5，则下面的范围可全部预料到：1-3、1-4、1-5、2-3、2-4和2-5。在本申请中，除非有其他说明，数值范围“a-b”表示a到b之间的任意实数组合的缩略表示，其中a和b都是实数。例如数值范围“0-5”表示本文中已经全部列出了“0-5”之间的全部实数，“0-5”只是这些数值组合的缩略表示。另外，当表述某个参数为≥2的整数，则相当于公开了该参数为例如整数2、3、4、5、6、7、8、9、10、11、12等。
如果没有特别的说明，本申请的所有实施方式以及可选实施方式可以相互组合形成新的技术方案。
如果没有特别的说明，本申请的所有技术特征以及可选技术特征可以相互组合形成新的技术方案。
如果没有特别的说明，本申请的所有步骤可以顺序进行，也可以随机进行，优选是顺序进行的。例如，方法包括步骤(a)和(b)，表示方法可包括顺序进行的步骤(a)和(b)，也可以包括顺序进行的步骤(b)和(a)。例如，提到方法还可包括步骤(c)，表示步骤(c)可以任意顺序加入到方法，例如，方法可以包括步骤(a)、(b)和(c)，也可包括步骤(a)、(c)和(b)，也可以包括步骤(c)、(a)和(b)等。
如果没有特别的说明，本申请所提到的“包括”和“包含”表示开放式，也可以是封闭式。例如，“包括”和“包含”可以表示还可以包括或包含没有列出的其他组分，也可以仅包括或包含列出的组分。
如果没有特别的说明，在本申请中，术语“或”是包括性的。举例来说，短语“A或B”表示“A，B，或A和B两者”。更具体地，以下任一条件均满足条件“A或B”：A为真(或存在)并且B为假(或不存在)；A为假(或不存在)而B为真(或存在)；或A和B都为真(或存在)。
如果没有特别的说明，多孔层是指第一多孔层、第二多孔层、或其组合。
如果没有特别的说明，第一多孔层与第二多孔层可以具有相同或不同的材质、相同或 不同的成分、相同或不同的孔径分布特征、相同或不同的尺寸、相同或不同的厚度。
[导电膜]
在一些实施方案中，本申请提供一种导电膜，导电膜包括：
基层，基层具有相对设置的第一表面和第二表面，基层具有致密结构；
第一多孔层，第一多孔层层叠结合于基层的第一表面；
第一多孔层的包括多孔导电材料；
多孔导电材料具有第一孔径的孔和第二孔径的孔；
第一孔径为n微米，0.5≤n≤10；
第二孔径为m纳米，20＜m＜200。
上述方案的导电膜具有层叠结合的基层和多孔层。其中，多孔层由于具有多孔结构，其力学强度相对较弱。采用具有良好的拉伸性能的基层(例如抗拉强度330N/mm 2以上)与多孔层层叠结合获得多层导电膜，该导电膜兼具增强的力学性能和多孔结构，适合用作二次电池集流体。
在一些实施方案中，术语“层叠结合”是指基层和多孔层在彼此层叠的位置上通过化学键(例如金属键)结合。基层和多孔层的结合强度可以通过胶带剥离测试检测，将胶带粘接在多孔层表面，然后剥离。基层和多孔层的结合强度可以抵抗σ 180°为7N/mm以上的胶带剥离，而多孔层不至脱落。
在一些实施方案中，术语“导电膜”是指在膜的面方向或厚度方向上，电导率为103(西门子/厘米)以上，例如10 5(西门子/厘米)以上，例如10 7(西门子/厘米)以上。
在一些实施方案中，基层为致密结构，基层的孔隙率例如为零。
上述方案的导电膜含有多孔导电材料，多孔导电材料具有创新的多级孔径分布特征。该新型多孔导电材料特别适合用于无负极(anode free)金属电池(例如无负极锂金属电池或无负极钠金属电池)或含活性金属/合金负极的电池。具有第一孔径的孔(简称大孔)的内壁可作为活性物质沉积的基底；此外，大孔的另一个作用是提供电解液浸润通道。具有第二孔径的孔(简称小孔)的内壁可作为活性物质沉积的基底。小孔提高了材料的比表面积，从而使多孔导电材料能装载更多的活性物质；此外，小孔的另一个作用是作为活性物质沉积的模板。具体来讲，受小孔尺寸的限制，沉积在小孔中的活性物质的具有纳米级尺寸，纳米级的活性物质因尺寸小而具有较高的离子电导率，进而能够提高电极整体的离子电导率，进而能够改善电池的倍率性能，最终在整体上提高电池的容量、循环稳定性以及倍率性能；此外，小孔的另一个作用是限制活性材料的体积膨胀，避免其粉化失效。
图1示出一个实施方式的导电膜的示意图，导电膜包括：基层100和第一多孔层110。基层100具有相对设置的第一表面101和第二表面102，基层100具有100Mpa以上的拉伸强度；第一多孔层110层叠结合于基层110的第一表面101；第一多孔层110的材质为多孔导电材料。
第一多孔层110上的虚线框引出了多孔导电材料60的局部放大示意图。多孔导电材料60具有大孔结构，大孔结构具有第一孔径的孔601，相邻的具有第一孔径的孔601之间通过第一棱丝600分隔。第一棱丝600上的虚线框引出了第一棱丝600的局部放大示意图。第一棱丝600具有小孔结构，小孔结构具有第二孔径的孔602，相邻的第二孔径的孔602之间通过第二棱丝604分隔。
基于上述方案的多孔导电材料具有创新的多级孔径分布特征。该新型多孔导电材料特别适合用于无负极(anode free)金属电池(例如无负极锂金属电池或无负极钠金属电池)或金属或合金负极电池。具有第一孔径的孔(简称大孔)的内壁可作为活性物质沉积的基底；此外，大孔的另一个作用是提供电解液浸润通道。具有第二孔径的孔(简称小孔)的内壁可作为活性物质沉积的基底。小孔提高了材料的比表面积，从而使多孔导电材料能装载更多的活性物质；此外，小孔的另一个作用是作为活性物质沉积的模板。具体来讲，受小孔尺寸的限制，沉积在小孔中的活性物质的具有纳米级尺寸，纳米级的活性物质因尺寸小而具有较高的离子电导率，进而能够提高电极整体的离子电导率，进而能够改善电池的倍率性能，最终在整体上提高电池的容量、循环稳定性以及倍率性能；此外，小孔的另一个作用是限制活性材料的体积膨胀，避免其粉化失效。
在一些实施方案中，第一孔径为n微米，0.5≤n≤10；n的取值可以0.5-1、1-2、2-3、3-4、4-5、5-6、6-7、7-8、8-9或9-10。0.5μm-10μm微米孔隙相较于尺寸更大的微米孔(300～700um)而言电池的容量发挥，循环稳定性及倍率性能更好(活性物质粒径减小，可以提高电极材料的离子电导率，进而提升电极整体的导电能力改善电池的倍率性能)，同时配合小孔隙的纳米孔，能进一步提升金属集流体的比表面积，从而能装载更多的活性物质。
在一些实施方案中，第二孔径为m纳米，20＜m＜200；m的取值可以为20-40、40-60、60-80、80-100、100-120、120-140、140-160、160-180或180-200。
图2示出本申请由一些实施方式的导电膜的示意图。在一些实施方案中，参考图2，导电膜还包括第二多孔层120，第二多孔层120层叠结合于基层100的第二表面102。第一多孔层110和第二多孔层120各自独立地包括多孔导电材料；多孔导电材料具有第一孔径的孔和第二孔径的孔；第一孔径为n微米，0.5≤n≤10；第二孔径为m纳米，20＜m＜200。基于此方案的导电膜的两侧表面均具有多孔层，导电膜的两侧均可以作为活性物质的集流面，该导电膜用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，多孔导电材料的表观体积为V，具有第一孔径的孔的总孔体积V 1，具有第二孔径的孔的总孔体积为V 2，多孔导电材料满足以下关系：(V 1+V 2)/V＝60％-90％。在一些实施方式中，(V 1+V 2)/V的值为20-30％、30-40％、40-50％、50-60％、60-70％、70-80％或80-90％。在一些实施方案中，V＝V 1+V 2。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，多孔导电材料的表观体积为V，具有第一孔径的孔的总孔体积V 1，多孔导电材料满足以下关系：V 1/V＝5％-70％。在一些实施方式中，V 1/V的值为5％-15％、 10％-15％、15％-20％、20％-30％、30％-40％、40％-50％、50％-60％或60％-70％。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，多孔导电材料的表观体积为V，具有第二孔径的孔的总孔体积为V 2，多孔导电材料满足以下关系：V 2/V＝15％-70％。在一些实施方式中，V 2/V的值为15％-20％、20％-30％、30％-40％、40％-50％、50％-60％或60％-70％。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，相邻的具有第一孔径的孔之间被第一棱丝间隔，第一棱丝的平均棱径为0.89μm-3μm(例如1μm-1.5μm、1.5μm-2μm、2μm-2.5μm、2.5μm-3μm)。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，相邻的具有第二孔径的孔之间被第二棱丝间隔，第二棱丝的平均棱径为27nm-100nm(例如30nm-40nm、40nm-50nm、50nm-60nm、60nm-70nm、70nm-80nm、80nm-90nm或90nm-100nm)。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，具有第一孔径的孔的总比表面积为0.08m 2/g-1.32m 2/g(例如0.1m 2/g-0.3m 2/g、0.3m 2/g-0.5m 2/g、0.5m 2/g-0.7m 2/g、0.7m 2/g-0.9m 2/g、0.9m 2/g-1.1m 2/g、1.1m 2/g-1.3m 2/g)。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，具有第二孔径的孔的总比表面积为0.87m 2/g-5.25m 2/g(例如1m 2/g-1.5m 2/g、1.5m 2/g-2m 2/g、2m 2/g-2.5m 2/g、2.5m 2/g-3m 2/g、3m 2/g-3.5m 2/g、3.5m 2/g-4m 2/g、4m 2/g-4.5m 2/g、4.5m 2/g-5m 2/g)。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，多孔导电材料的比表面积为0.95m 2/g-6.57m 2/g(例如1m 2/g-1.5m 2/g、1.5m 2/g-2m 2/g、2m 2/g-2.5m 2/g、2.5m 2/g-3m 2/g、3m 2/g-3.5m 2/g、3.5m 2/g-4m 2/g、4m 2/g-4.5m 2/g、4.5m 2/g-5m 2/g、5m 2/g-5.5m 2/g、5.5m 2/g-6m 2/g)。多孔导电材料的比表面积例如可以等于具有第一孔径的孔的总比表面积与具有第二孔径的孔的总比表面积之和。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，基层的厚度为4.5μm-12μm，例如4.5μm-6μm、6μm-8μm、8μm-10μm、10μm-12μm。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，第一多孔层的厚度为50μm-200μm，例如50μm-100μm、100μm-150μm、150μm-200μm。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池， 二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，第二多孔层的厚度为50μm-200μm，例如50μm-100μm、100μm-150μm、150μm-200μm。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，导电膜的总厚度为50μm-450μm。导电膜的总厚度例如可以为50μm-100μm、100μm-150μm、150μm-200μm、200μm-250μm、250μm-300μm、300μm-350μm、350μm-400μm、400μm-450μm。
在一些实施方案中，多孔导电材料的材质为含有M元素的金属单质或合金，M元素选自铜、铝或其组合。例如，多孔导电材料的材质为铜或铜合金。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，多孔导电材料是采用脱合金方法制备获得的。
在一些实施方案中，多孔导电材料为气体可透过的和/液体可透过的。
在一些实施方案中，所述基层具有330N/m 2以上的拉伸强度。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，所述导电膜具有100N/mm 2以上的拉伸强度。基于此方案的导电膜具有令人满意的强度，而且其用于二次电池，二次电池表现出改善的容量、循环稳定性和/或倍率性能。
在一些实施方案中，基层例如具有330N/mm 2～500N/mm 2的拉伸强度，例如具有330N/mm 2～400N/mm 2的拉伸强度，例如具有400N/mm 2～450N/mm 2，例如具有450N/mm 2～500N/mm 2的拉伸强度。
在一些实施方案中，导电膜例如具有330N/mm 2～500N/mm 2的拉伸强度，例如具有330N/mm 2～400N/mm 2的拉伸强度，例如具有400N/mm 2～450N/mm 2，例如具有450N/mm 2～500N/mm 2的拉伸强度。
在一些实施方案中，所述基层具有单层结构或多层结构。
在一些实施方案中，基层100具有单层结构或多层结构，例如基层可以具有两层结构或三层结构。在基层100具有多层结构的技术方案中，通过对基层100的各层材料进行针对性地设计，能够获得综合性能较好的基层。例如，在基层中设置致密的金属材料层，使基层具有较高的拉伸强度。例如在基层中设置一层或多层导电胶层，使基层能够方便牢固地与多孔层层叠符合。
图14示出本申请又一些实施方式的导电膜的示意图。如图所示，在一些实施方案中，所述基层100具有多层结构，所述基层100包括主体层1005和层叠在主体层1005一侧表面的第一导电胶层1001，所述第一导电胶层1001背向所述主体层1005的表面构成所述基层100的第一表面101。
图15示出本申请又一些实施方式的导电膜的示意图。如图所示，在一些实施方案中，所述基层100具有多层结构，所述基层100包括主体层1005和分别层叠在主体层1005相对两侧表面的第一导电胶层1001和第二导电胶层1002，所述第一导电胶层1001背向所述主体层1005的表面构成所述基层的第一表面101，所述第二导电胶层1002背向所述主体层1005的表面构成所述基层的第二表面102。
在一些实施方案中，主体层1005与第一导电胶层1001的厚度之比为4.5-12:1-10，例如4.5～8:2，例如5～7:2。
在一些实施方案中，主体层1005与第二导电胶层1002的厚度之比为4.5-12:1-10，例如4.5～8:2，例如5～7:2。
在一些实施方案中，导电胶含有粘性成分和导电成分。
在一些实施方案中，粘性成分选自环氧树脂、有机硅树脂、聚酰亚胺树脂、聚氨酯、丙烯酸树脂中的一种或多种。
在一些实施方案中，导电成分选自碳材料(如碳纳米管)、金属材料(如Au、Ag、Cu、Ni)中的一种或多种。
在一些实施方案中，导电胶的电导率例如为1.1×10 -10西门子/米(S/m)以上。
在第二方面，本申请提供一种导电膜的制备方法，导电膜的定义如上文任一实施方案所述，制备方法包括：
(1)提供第一原料多层体，第一原料多层体包括：
原料基层，原料基层具有相对设置的第一表面和第二表面，原料基层致密结构；
第一A合金层，第一A合金层层叠结合于原料基层的第一表面，第一A合金层的材质为多相合金，多相合金含有αMn相和(M,γMn)相，M元素选自铜、铝或其组合；以及
可选地，第一B合金层，第一B合金层层叠结合于原料基层的第二表面，第一B合金层的材质为多相合金，多相合金含有αMn相和(M,γMn)相，M元素选自铜、铝或其组合；
(2)采用脱合金化的方法从多相合金的αMn相去除至少部分Mn元素，以及从多相合金的(M,γMn)相去除至少部分Mn元素；
其中，原料基层被配置为在脱合金处理的过程中保持完整。
在一些实施方案中，原料基层在脱合金处理的过程中不发生脱合金反应。基层的材质可以性质相对不活泼的金属，例如为标准电极电位大于零的金属，例如Cu、Ni、Ag、Pt、Au、或其合金。
上述方法巧妙利用了多相合金中αMn相和(M,γMn)相在脱合金过程的不同化学反应，αMn相在脱合金的过程中被脱除形成具有第一孔径的孔，(M,γMn)相中的Mn元素在脱合金的过程中被脱除形成具有第二孔径的孔，进而获得了具有本申请的具有新型多孔结构的导电膜。根据Mn-Cu二元合金相图，Mn-Cu二元合金(Mn含量90-60at.％)在700-865℃ 温度区间为(M,γMn)单相结构，而在500-700℃温度区间为α/γ双相结构。因此，熔炼制备的Mn-Cu合金可以先在高温(700-865℃)退火处理，得到塑性加工能力极佳的(M,γMn)单相合金，制备出不同形状的前驱体合金。随后进行低温(500-700℃)时效处理，形成α/γ双相结构，用于制备最终的多孔导电材料。
在一些实施方式中，αMn是具有cbcc结构的锰的同素异形体。
在一些实施方式中，(M,γMn)相是元素M溶于γMn形成的固溶体相。例如(Cu,γMn)相是元素Cu溶于γMn形成的固溶体相。
在一些实施方式中，固溶体是一种或多种溶质组元溶入晶态溶剂并保持溶剂的晶格类型所形成的单相晶态固体。
在一些实施方式中，以αMn相中的全部Mn元素为基准，采用脱合金化的方法从αMn相去除至少90at.％以上的Mn元素。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，以(M,γMn)相中的全部Mn元素为基准，采用脱合金化的方法从(M,γMn)相去除至少90at.％以上的Mn元素。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，以多相合金中的全部M元素为基准，脱合金化的方法对M元素去除的量为10at.％以下。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，αMn相中Mn元素的含量>99at.％。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，(M,γMn)相中Mn元素的含量为40-80at.％。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，(M,γMn)相为固溶体。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，多相合金中αMn相的含量为22-70vol％。基于此，获得的多孔导电材料具有创新的孔分布特征。在一些实施方式中，多相合金中αMn相的含量为22-70vol％，例如22-30vol％、30-40vol％、40-50vol％、50-60vol％、60-70vol％，(M,γMn)相的含量为30-78vol％，例如、30-40vol％、40-50vol％、50-60vol％、60-78vol％。
在一些实施方式中，多相合金中(M,γMn)相的含量为30-78vol％。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，αMn相和(M,γMn)相均匀地分散在多相合金中。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，多相合金含有Mn元素和M元素，Mn元素的含量为60％-90at.％，M元素的含量为10-40at.％，M元素选自铜、铝或其组合。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，脱合金过程主要基于前驱体组分标准电化学电位的差异，将体系中相对活泼的元素选择性去除，而剩余的金属原子相互连接，得到多孔导电材料。
在一些实施方式中，脱合金化的方法选自化学腐蚀、电化学腐蚀、或其组合。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方案中，本申请制备导电膜的方法还包括制备第一原料多层体的步骤，具体包括：
(1)提供第二原料多层体，第二原料多层体包括：
原料基层，原料基层具有相对设置的第一表面和第二表面，原料基层具有致密结构；
第二A合金层，第二A合金层层叠结合于原料基层的第一表面，第二A合金层中(M,γMn)相的含量为95vol％以上；以及
可选地，第二B合金层，第二B合金层层叠结合于原料基层的第一表面，第二B合金层中(M,γMn)相的含量为95vol％以上；
(2)对上一步产物进行分相热处理，在第二A合金层和/或第二B合金层中形成多相合金，多相合金含有αMn相和(M,γMn)相，获得第一原料多层体。
在一些实施方案中，本申请制备导电膜的方法还包括制备第一原料多层体的步骤，具体包括：
(1)提供γ单相合金箔，所述γ单相合金箔中(M,γMn)相的含量为95vol％以上；
(2)对γ单相合金箔进行分相热处理，获得多相合金箔，所述多相合金箔含有αMn相和(M,γMn)相；
(3)提供原料基层，所述原料基层包括主体层和层叠在所述主体层一侧表面的第一导电胶层，以及可选地，还包括层叠在所述主体层另一侧表面的第二导电胶层；
(4)在所述第一导电胶层背向所述原料基层的表面层叠结合多相合金箔，以及可选地，在所述第二导电胶层背向所述原料基层的表面层叠结合多相合金箔，获得第一原料多层体。
含有(M,γMn)相的第二A合金层/第二B合金层具有出色的室温塑性。通过锻造、轧制、拉拔等塑性加工的方法加工第一产物，能够获得不同形状、尺寸的加工产物。该加工产物在后续的热处理及脱合金过程，能够保持形状与尺寸的稳定。
在一些实施方案中，第二原料多层体是采用层叠轧制的方法制备获得的，例如采用层叠热轧的方法制备获得。在一个实施方式中，可以将(M,γMn)相合金箔和铜箔按照需要的顺序层叠后进行热轧，获得第二原料多层体。
在一些实施方案中，分相热处理的温度500-700℃。
在一些实施方案中，分相热处理的时间为1-4小时。
在一些实施方案中，分相热处理后采用20-1000℃/s的冷却速度进行冷却。
在一些实施方案中，第二A合金层和/或第二A合金层的材质为铜锰合金，Mn元素的含量为60％-90％。
在一些实施方案中，(M,γMn)相的含量为95vol％以上的γ单相合金可以通过对铜锰合 金进行第一热处理获得。
在一些实施方式中，第一热处理的温度700-865℃。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，第一热处理的时间为0.16小时以上，例如1-2小时。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，第一热处理后采用20-1000℃/s的冷却速度进行冷却，例如水冷冷却。基于此，获得的多孔导电材料具有创新的孔分布特征。
在一些实施方式中，方法还包括在进行分相热处理前对第一产物进行塑性加工的操作。
在一些实施方案中，分相热处理被配置为将部分(M,γMn)相转化为αMn相。
在一些实施方案中，原料基层具有330N/mm 2以上的抗拉强度(例如基层具有330N/mm 2～500N/mm 2的抗拉强度，例如具有330N/mm 2～400N/mm 2的抗拉强度，例如具有400N/mm 2～500N/mm 2的抗拉强度)
在第二方面，本申请提供一种集流体，包括上述任一项的多孔导电材料。
在第三方面，本申请提供一种二次电池，包括上述任一项的集流体；
在一些实施方案中，二次电池是无负极金属电池；
在一些实施方案中，二次电池的负极活性材料含有金属或合金。
在第四方面，本申请提供一种装置，包括上述任一项的二次电池，二次电池向装置提供电能。
[二次电池]
二次电池又称为充电电池或蓄电池，是指在电池放电后可通过充电的方式使活性材料激活而继续使用的电池。
通常情况下，二次电池包括正极极片、负极极片、隔离膜及电解液。在电池充放电过程中，活性离子(例如锂离子)在正极极片和负极极片之间往返嵌入和脱出。隔离膜设置在正极极片和负极极片之间，主要起到防止正负极短路的作用，同时可以使活性离子通过。电解液在正极极片和负极极片之间，主要起到传导活性离子的作用。
[正极极片]
正极极片通常包括正极集流体以及设置在正极集流体至少一个表面的正极膜层，正极膜层包括正极活性材料。正极集流体和正极膜层之间可设置有表面处理组合物。
作为示例，正极集流体具有在其自身厚度方向相对的两个表面，正极膜层设置在正极集流体相对的两个表面的其中任意一者或两者上。
在一些实施方式中，正极集流体可以含有本申请上述任一项的多孔导电材料。正极集流体还可以是复合集流体，例如可通过将上述任一项的多孔导电材料与高分子材料基材(如聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯 乙烯(PS)、聚乙烯(PE)等的基材)复合形成。
在一些实施方式中，正极活性材料可采用本领域公知的用于电池的正极活性材料。作为示例，正极活性材料可包括以下材料中的至少一种：橄榄石结构的含锂磷酸盐、锂过渡金属氧化物及其各自的改性化合物。但本申请并不限定于这些材料，还可以使用其他可被用作电池正极活性材料的传统材料。这些正极活性材料可以仅单独使用一种，也可以将两种以上组合使用。其中，锂过渡金属氧化物的示例可包括但不限于锂钴氧化物(如LiCoO 2)、锂镍氧化物(如LiNiO 2)、锂锰氧化物(如LiMnO 2、LiMn 2O 4)、锂镍钴氧化物、锂锰钴氧化物、锂镍锰氧化物、锂镍钴锰氧化物(如LiNi 1/3Co 1/3Mn 1/3O 2(也可以简称为NCM333)、LiNi 0.5Co 0.2Mn 0.3O 2(也可以简称为NCM523)、LiNi 0.5Co 0.25Mn 0.25O 2(也可以简称为NCM211)、LiNi 0.6Co 0.2Mn 0.2O 2(也可以简称为NCM622)、LiNi 0.8Co 0.1Mn 0.1O 2(也可以简称为NCM811)、锂镍钴铝氧化物(如LiNi 0.85Co 0.15Al 0.05O 2)及其改性化合物等中的至少一种。橄榄石结构的含锂磷酸盐的示例可包括但不限于磷酸铁锂(如LiFePO 4(也可以简称为LFP))、磷酸铁锂与碳的复合材料、磷酸锰锂(如LiMnPO 4)、磷酸锰锂与碳的复合材料、磷酸锰铁锂、磷酸锰铁锂与碳的复合材料中的至少一种。
在一些实施方式中，正极膜层还可选地包括表面处理。作为示例，表面处理可以包括聚偏氟乙烯(PVDF)、聚四氟乙烯(PTFE)、偏氟乙烯-四氟乙烯-丙烯三元共聚物、偏氟乙烯-六氟丙烯-四氟乙烯三元共聚物、四氟乙烯-六氟丙烯共聚物及含氟丙烯酸酯树脂中的至少一种。
在一些实施方式中，正极膜层还可选地包括导电剂。作为示例，导电剂可以包括超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯及碳纳米纤维中的至少一种。
在一些实施方式中，可以通过以下方式制备正极极片：将上述用于制备正极极片的组分，例如正极活性材料、导电剂、表面处理和任意其他的组分分散于溶剂(例如N-甲基吡咯烷酮)中，形成正极浆料；将正极浆料涂覆在正极集流体上，经烘干、冷压等工序后，即可得到正极极片。
[负极集流体及负极极片]
本申请的导电膜可以直接作为无负极(anode free)金属电池(例如无负极锂金属电池或无负极钠金属电池)的负极侧集流体(或电极)。
在无锂负极电池中，所有活性锂离子最初都存储在正极材料中，在初始充电过程中，锂离子从正极提取，移至负极，并直接原位电镀在负极裸集流体上，形成锂金属负极。随后，在放电过程中，将活性锂离子从原位形成的锂金属负极上剥离，并嵌入到正极中。无锂负极电池的体积小，且具有较大的能量密度。
本申请的多孔导电材料还可以作为含活性金属/合金负极的电池的负极侧集流体。
在一些实施方案中，活性金属/合金例如是锂金属或锂合金。
在一些实施方案中，锂金属电池的负极极片以本申请多孔导电材料作为负极集流体， 在多孔导电材料的外表面和/或孔隙内部沉积锂金属层。
本文中使用的术语“锂合金”旨在表示能够通过充电与锂形成合金并能够可逆地吸附和释放锂的物质。能够与锂形成合金的物质的实例包括诸如锡(Sn)、硅(Si)、锌(Zn)、铝(Al)、镁(Mg)、铟(In)、镉(Cd)、铅(Pb)、铋(Bi)和锑(Sb)的金属的元素及其化合物和其合金(包括锂与这些元素金属的合金)。可以通过适当的选择来适宜地使用这些物质中的一种或两种或更多种。
在一些实施方案中，除了锂金属或锂合金之外的其它活性金属/合金包括诸如锡(Sn)、硅(Si)、锌(Zn)、铝(Al)、镁(Mg)、铟(In)、镉(Cd)、铅(Pb)、铋(Bi)和锑(Sb)的金属的元素及其化合物和其合金(包括锂与这些元素金属的合金)。
在一些实施方案中，可以采用电沉积、气相沉积(如物理/化学气相沉积)、磁控溅射等方法将活性金属/合金沉积在多孔导电材料的表面和空隙内部，从而获得电池负极。
[电解质]
电解质在正极极片和负极极片之间起到传导离子的作用。本申请对电解质的种类没有具体的限制，可根据需求进行选择。例如，电解质可以是液态的、凝胶态的或全固态的。
在一些实施方式中，电解质为液态的，且包括电解质盐和溶剂。
在一些实施方式中，电解质盐可选自六氟磷酸锂、四氟硼酸锂、高氯酸锂、六氟砷酸锂、双氟磺酰亚胺锂、双三氟甲磺酰亚胺锂、三氟甲磺酸锂、二氟磷酸锂、二氟草酸硼酸锂、二草酸硼酸锂、二氟二草酸磷酸锂及四氟草酸磷酸锂中的至少一种。
在一些实施方式中，溶剂可选自碳酸亚乙酯、碳酸亚丙酯、碳酸甲乙酯、碳酸二乙酯、碳酸二甲酯、碳酸二丙酯、碳酸甲丙酯、碳酸乙丙酯、碳酸亚丁酯、氟代碳酸亚乙酯、甲酸甲酯、乙酸甲酯、乙酸乙酯、乙酸丙酯、丙酸甲酯、丙酸乙酯、丙酸丙酯、丁酸甲酯、丁酸乙酯、1,4-丁内酯、环丁砜、二甲砜、甲乙砜及二乙砜中的至少一种。
在一些实施方式中，电解液还可选地包括添加剂。作为示例，添加剂可以包括负极成膜添加剂、正极成膜添加剂，还可以包括能够改善电池某些性能的添加剂，例如改善电池过充性能的添加剂、改善电池高温或低温性能的添加剂等。
[隔离膜]
在一些实施方式中，二次电池中还包括隔离膜。本申请对隔离膜的种类没有特别的限制，可以选用任意公知的具有良好的化学稳定性和机械稳定性的多孔结构隔离膜。
在一些实施方式中，隔离膜的材质可选自玻璃纤维、无纺布、聚乙烯、聚丙烯及聚偏二氟乙烯中的至少一种。隔离膜可以是单层薄膜，也可以是多层复合薄膜，没有特别限制。在隔离膜为多层复合薄膜时，各层的材料可以相同或不同，没有特别限制。
在一些实施方式中，正极极片、负极极片和隔离膜可通过卷绕工艺或叠片工艺制成电极组件。
在一些实施方式中，二次电池可包括外包装。该外包装可用于封装上述电极组件及电解质。
在一些实施方式中，二次电池的外包装可以是硬壳，例如硬塑料壳、铝壳、钢壳等。二次电池的外包装也可以是软包，例如袋式软包。软包的材质可以是塑料，作为塑料，可列举出聚丙烯、聚对苯二甲酸丁二醇酯以及聚丁二酸丁二醇酯等。
本申请对二次电池的形状没有特别的限制，其可以是圆柱形、方形或其他任意的形状。例如，图9是作为一个示例的方形结构的二次电池5的整体图和分解图。
在一些实施方式中，参照图9，外包装可包括壳体51和盖板53。其中，壳体51可包括底板和连接于底板上的侧板，底板和侧板围合形成容纳腔。壳体51具有与容纳腔连通的开口，盖板53能够盖设于开口，以封闭容纳腔。正极极片、负极极片和隔离膜可经卷绕工艺或叠片工艺形成电极组件52。电极组件52封装于容纳腔内。电解液浸润于电极组件52中。二次电池5所含电极组件52的数量可以为一个或多个，本领域技术人员可根据具体实际需求进行选择。
在一些实施方式中，二次电池可以组装成电池模块，电池模块所含二次电池的数量可以为一个或多个，具体数量本领域技术人员可根据电池模块的应用和容量进行选择。
图10是作为一个示例的电池模块4。参照图10，在电池模块4中，多个二次电池5可以是沿电池模块4的长度方向依次排列设置。当然，也可以按照其他任意的方式进行排布。进一步可以通过紧固件将该多个二次电池5进行固定。
可选地，电池模块4还可以包括具有容纳空间的外壳，多个二次电池5容纳于该容纳空间。
在一些实施方式中，上述电池模块还可以组装成电池包，电池包所含电池模块的数量可以为一个或多个，具体数量本领域技术人员可根据电池包的应用和容量进行选择。
图11和图12是作为一个示例的电池包1。参照图11和图12，在电池包1中可以包括电池箱和设置于电池箱中的多个电池模块4。电池箱包括上箱体2和下箱体3，上箱体2能够盖设于下箱体3，并形成用于容纳电池模块4的封闭空间。多个电池模块4可以按照任意的方式排布于电池箱中。
另外，本申请还提供一种装置，装置包括本申请提供的二次电池、电池模块、或电池包中的至少一种。二次电池、电池模块、或电池包可以用作装置的电源，也可以用作装置的能量存储单元。装置可以包括移动设备(例如手机、笔记本电脑等)、电动车辆(例如纯电动车、混合动力电动车、插电式混合动力电动车、电动自行车、电动踏板车、电动高尔夫球车、电动卡车等)、电气列车、船舶及卫星、储能***等，但不限于此。
作为装置，可以根据其使用需求来选择二次电池、电池模块或电池包。
图13是作为一个示例的装置。该装置为纯电动车、混合动力电动车、或插电式混合动力电动车等。为了满足该装置对二次电池的高功率和高能量密度的需求，可以采用电池包或电池模块。
实施例1：
(1)制备第二原料多层体
提供铜金属(纯度＞99％)和锰金属(纯度＞99％)，采用真空感应熔炼炉熔炼为合金铸锭，本例中合金铸锭成分为Mn 60Cu 40(下标表述原子比)。
对合金铸锭进行锻造，锻造压力为20t，每锻造一次后进行去应力退火操作，退火温度为800℃，退火时间为60min，退火后水冷。
对锻造后的合金铸锭进行第一热处理，第一热处理温度为800℃，时间为60min。参考图6示出的Mn-Cu相图，可以得知第一热处理后的产物为由(Cu,γMn)相构成的单相合金(简称γ单相合金)。
对该γ单相合金进行初步热轧制，获得合金箔材。将合金箔材与紫铜箔原料(抗拉强度370N/mm 2)按照“合金箔材/紫铜箔/合金箔材”的层叠方式层叠，然后进行多次轧制，至产品达到目标厚度，获得第二原料多层体。
第二原料多层体包括：原料基层、第二A合金层和第二B合金层。原料基层具有相对设置的第一表面和第二表面，原料基层具有370N/mm 2的抗拉强度；第二A合金层层叠结合于原料基层的第一表面，第二A合金层的材质为(Cu,γMn)，第二B合金层的材质为(Cu,γMn)。
(2)制备第一原料多层体
对第二原料多层体进行分相热处理，分相热处理温度为650℃，热处理时间为4h，得到第一原料多层体。参考图6示出的Mn-Cu相图，可以得知分相热处理后，第二A合金层将转变为第一A合金层，其材质转变为含有αMn相和(Cu,γMn)相的多相合金，第二B合金层将转变为第一B合金层，其材质转变为含有αMn相和(Cu,γMn)相的多相合金。
第一原料多层体包括：原料基层、第一合金层和第二合金层。原料基层具有相对设置的第一表面和第二表面，原料基层具有致密结构且具有370N/mm 2的抗拉强度。第一合金层层叠结合于原料基层的第一表面，第一合金层的材质为含有αMn相和(Cu,γMn)相的多相合金。第二合金层层叠结合于原料基层的第二表面，第二合金层的材质为含有αMn相和(Cu,γMn)相的多相合金。
(3)脱合金
将第一原料多层体置于足量的2.38mol/L HCl水溶液中，进行自由腐蚀法脱合金，温度为25℃。待无明显气泡逸出，脱合金完成，即得到实施例1的导电膜。
对于原料基层，其在脱合金的过程中结构和性质基本不改变，脱合金后其成分和拉伸强度与紫铜箔原料一致。对于第一合金层和第二合金层，含有αMn相和(Cu,γMn)相的多相合金经过脱合金处理后，能够形成多孔导电材料(此处为多孔铜)，参考图1的多孔导电材料的示意图，脱合金的原理如下：
(1)经脱合金处理后，多相合金中的αMn相会被脱除，αMn脱除的位置会形成具有第一孔径的孔601；
(2)经脱合金处理后，多相合金中的(Cu,γMn)相会被部分脱除，(Cu,γMn)相中的Mn元素部分会被脱除，Cu元素部分会被保留，保留的Cu元素部分会构成第一棱丝600，脱除的Mn元素部分会形成具有第二孔径的孔602。
图2示出实施例1的导电膜的截面示意图和截面的扫描电子显微镜照片。导电膜包括：基层100、第一多孔层110和第二多孔层120。基层100具有相对设置的第一表面101和第二表面102，基层100具有致密结构且具有330N/mm 2以上的抗拉强度；第一多孔层110层叠结合于基层110的第一表面101；第二多孔层120层叠与基层的第二表面120。第一多孔层110和第二多孔层120的材质为多孔导电材料(此处为多孔铜)。基层100的厚度为6μm、第一多孔层110的厚度为120μm和第二多孔层120的厚度为120μm。基层100的材质为致密紫铜，抗拉强度与；第一多孔层110和第二多孔层120的材质均为多孔铜。
图3示出实施例1的第一多孔层101的表面的扫描电子显微镜照片。如图所示，第一多孔层101的材质为多孔导电材料，多孔导电材料具有第一孔径的孔(简称大孔)和具有第二孔径的孔(简称小孔)。从扫描电子显微镜照片上选取50-100个大孔和50-100个小孔，分别测量大孔和小孔的孔径和棱丝直径，分别计算平均值，结果详见表1。
实施例2
实施例2与实施例1的区别在于：步骤(1)的合金铸锭成分为Mn 75Cu 25。
实施例2的导电膜的制备方法如下：
(1)制备第二原料多层体
提供铜金属(纯度＞99％)和锰金属(纯度＞99％)，采用真空感应熔炼炉熔炼为合金铸锭，本例中合金铸锭成分为Mn 75Cu 25(下标表述原子比)。
对合金铸锭进行锻造，锻造压力为20t，每锻造一次后进行去应力退火操作，退火温度为800℃，退火时间为60min，退火后水冷。对锻造后的合金铸锭进行第一热处理，第一热处理温度为800℃，时间为60min，得到由(Cu,γMn)相构成的单相合金(简称γ单相合金)。
对该γ单相合金进行初步热轧制，获得合金箔材。将合金箔材与紫铜箔原料按照“合金箔材/紫铜箔/合金箔材”的层叠方式层叠，然后进行多次轧制，至产品达到目标厚度，获得第二原料多层体。
第二原料多层体包括：原料基层、第二A合金层和第二B合金层。原料基层具有相对设置的第一表面和第二表面，原料基层具有致密结构且具有359N/mm 2的抗拉强度；第二A合金层层叠结合于原料基层的第一表面，第二A合金层的材质为(Cu,γMn)，第二B合金层的材质为(Cu,γMn)。第二A合金层的XRD图谱如图7的(a)所示，图中能够观察到(Cu,γMn)相的衍射峰。
(2)制备第一原料多层体
对第二原料多层体进行分相热处理，分相热处理温度为650℃，热处理时间为4h，得到第一原料多层体。
第一原料多层体包括：原料基层、第一A合金层和第一B合金层。原料基层具有相对设置的第一表面和第一表面，原料基层具有359N/mm 2的抗拉强度；第一A合金层层叠结合于原料基层的第一表面，第一A合金层的材质为多相合金，第一B合金层的材质为多相合金。第一A合金层的XRD图谱如图7的(b)所示，图中能够观察到αMn相的衍射峰和(Cu,γMn)相的衍射峰。
(3)脱合金
将第一原料多层体置于足量的2.38mol/L HCl水溶液中，进行自由腐蚀法脱合金，温度为25℃。待无明显气泡逸出，脱合金完成，即得到实施例2的导电膜。
实施例2的导电膜包括：基层100、第一多孔层110和第二多孔层120。基层100具有相对设置的第一表面101和第二表面102，基层100具有359N/mm 2的抗拉强度；第一多孔层110层叠结合于基层110的第一表面101；第二多孔层120层叠与基层的第二表面120。第一多孔层110和第二多孔层120的材质为多孔导电材料(此处为多孔铜)。基层100的厚度为6μm、第一多孔层110的厚度为120μm和第二多孔层120的厚度为120μm。基层100的材质为致密紫铜；第一多孔层110和第二多孔层120的材质均为多孔铜。
图4示出实施例2的第一多孔层101的表面的扫描电子显微镜照片。如图所示，第一多孔层101的材质为多孔导电材料，多孔导电材料具有第一孔径的孔(简称大孔)和具有第二孔径的孔(简称小孔)。从扫描电子显微镜照片上选取50-100个大孔和50-100个小孔，分别测量大孔和小孔的孔径和棱丝直径，分别计算平均值，结果详见表1。
第一多孔层的XRD图谱如图7的(c)所示，图中能够观察到Cu相的衍射峰。
实施例3：
实施例3与实施例1的区别在于：步骤(1)的合金铸锭成分为Mn 90Cu 10。
实施例3的导电膜制备方法如下：
(1)制备第二原料多层体
提供铜金属(纯度＞99％)和锰金属(纯度＞99％)，采用真空感应熔炼炉熔炼为合金铸锭，本例中合金铸锭成分为Mn 90Cu 10(下标表述原子比)。
对合金铸锭进行锻造，锻造压力为20t，每锻造一次后进行去应力退火操作，退火温度为800℃，退火时间为60min，退火后水冷。对锻造后的合金铸锭进行第一热处理，第一热处理温度为800℃，时间为60min，得到由(Cu,γMn)相构成的单相合金(简称γ单相合金)。
对该γ单相合金进行初步热轧制，获得合金箔材。将合金箔材与紫铜箔原料按照“合金箔材/紫铜箔/合金箔材”的层叠方式层叠，然后进行多次轧制，至产品达到目标厚度，获得第二原料多层体。
(2)制备第一原料多层体
对第二原料多层体进行分相热处理，分相热处理温度为650℃，热处理时间为4h，得到第一原料多层体。
第一原料多层体包括：原料基层、第一A合金层和第一B合金层。原料基层具有相对设置的第一表面和第一表面，原料基层具有致密结构且具有360N/mm 2的抗拉强度；第一A合金层层叠结合于原料基层的第一表面，第一A合金层的材质为多相合金，第一B合金层的材质为多相合金。
(3)脱合金
将第一原料多层体置于足量的2.38mol/L HCl水溶液中，进行自由腐蚀法脱合金，温度为25℃。待无明显气泡逸出，脱合金完成，即得到实施例2的导电膜。
实施例2的导电膜包括：基层100、第一多孔层110和第二多孔层120。基层100具有相对设置的第一表面101和第二表面102，基层100具有360N/mm 2的抗拉强度；第一多孔层110层叠结合于基层110的第一表面101；第二多孔层120层叠与基层的第二表面120。第一多孔层110和第二多孔层120的材质为多孔导电材料(此处为多孔铜)。基层100的厚度为6μm、第一多孔层110的厚度为120μm和第二多孔层120的厚度为120μm。基层100的材质为致密紫铜；第一多孔层110和第二多孔层120的材质均为多孔铜。
图5示出实施例3的第一多孔层101的表面的扫描电子显微镜照片。如图所示，第一多孔层101的材质为多孔导电材料，多孔导电材料具有第一孔径的孔(简称大孔)和具有第二孔径的孔(简称小孔)。从扫描电子显微镜照片上选取50-100个大孔和50-100个小孔，分别测量大孔和小孔的孔径和棱丝直径，分别计算平均值，结果参见表1。
实施例4-9
实施例4-9与实施例2的区别在于以下一项或多项：
(1)第一多孔层和第二多孔层的厚度与实施例2不同；
(2)基层的厚度与实施例2不同。
实施例4-9的导电膜的参数如下表1所示。
实施例10-12
实施例10-12与实施例2的区别在于：多孔导电材料的大孔孔径与实施例2不同，详见表1。
具体通过调整去合金化脱合金时间来改变大孔孔径。
实施例10中，脱合金腐蚀液为2.2mol/L HCl水溶液，脱合金温度为25℃，脱合金时间为6h。
实施例11中，脱合金腐蚀液为2.38mol/L HCl水溶液，脱合金温度为25℃，脱合金时间为36h。
实施例12中，脱合金腐蚀液为2.38mol/L HCl水溶液，脱合金温度为25℃，脱合金时间为60h。
实施例13-15
实施例13-15与实施例2的区别在于：多孔导电材料的小孔孔径与实施例2不同，详见表1。
具体通过调整脱合金的参数来改变小孔孔径。
实施例13中，脱合金的温度为25℃。
实施例14中，脱合金的温度为35℃。
实施例15中，脱合金的温度为40℃。
实施例16
(1)制备γ单相合金箔
提供铜金属(纯度＞99％)和锰金属(纯度＞99％)，采用真空感应熔炼炉熔炼为合金铸锭，本例中合金铸锭成分为Mn 75Cu 25(下标表述原子比)。
对合金铸锭进行锻造，锻造压力为20t，每锻造一次后进行去应力退火操作，退火温度为800℃，退火时间为60min，退火后水冷。
对锻造后的合金铸锭进行第一热处理，第一热处理温度为800℃，时间为60min。参考图6示出的Mn-Cu相图，可以得知第一热处理后的产物为由(Cu,γMn)相构成的单相合金(简称γ单相合金)。
对该γ单相合金进行热轧制，轧制到厚度为120um，获得最终的γ单相合金箔。
(2)制备多相合金箔
对上述γ单相合金箔进行分相热处理，分相热处理温度为650℃，热处理时间为4h，得到多相合金箔。参考图6示出的Mn-Cu相图，可以得知分相热处理后，具有(Cu,γMn)相的γ单相合金箔转变为含有αMn相和(Cu,γMn)相的多相合金箔。
(3)制备第一原料多层体
将两张多相合金箔与两侧表面涂有导电胶的紫铜箔(抗拉强度350N/mm 2)层叠。层叠顺序按照“多相合金箔/紫铜箔/多相合金箔”。然后将它们压制以复合，压制压力为0.3T，获得第一原料多层体。其中，导电胶的材质为碳纳米管填充的E-44环氧树脂。导电胶中碳纳米管的含量为2wt％，导电胶的电导率为2.1×10 -7西门子/米(S/m)。
第一原料多层体包括：原料基层、第一合金层和第二合金层。原料基层具有多层结构(三明治样的多层结构)。原料基层包括主体层(材质为铜)和分别层叠在铜主体层两侧的第一导电胶层和第二导电胶层。第一导电胶层背向铜主体层的表面构成原料基层的第一表面；第二导电胶层背向铜主体层的表面构成原料基层的第二表面。原料基层具有致密结构且具有350N/mm 2的抗拉强度。第一合金层层叠结合于原料基层的第一表面，第一合金层的材质为含有αMn相和(Cu,γMn)相的多相合金。第二合金层层叠结合于原料基层的第二表面，第二合金层的材质为含有αMn相和(Cu,γMn)相的多相合金。
(3)脱合金
将第一原料多层体置于足量的2.38mol/L HCl水溶液中，进行自由腐蚀法脱合金，温度为25℃。待无明显气泡逸出，脱合金完成，即得到实施例16的导电膜。
图15示出本实施例的导电膜的示意图。如图所示，导电膜包括：基层100和第一多孔层110。基层100具有相对设置的第一表面101和第二表面102，基层100具有100Mpa以上的拉伸强度；第一多孔层110层叠结合于基层110的第一表面101；第一多孔层110的材质为多孔导电材料。导电膜还包括第二多孔层120，第二多孔层120层叠结合于基层100的第二表面102。
所述基层100具有多层结构，所述基层100包括主体层1005和分别层叠在主体层1005相对两侧表面的第一导电胶层1001和第二导电胶层1002，所述第一导电胶层1001背向所述主体层1005的表面构成所述基层的第一表面101，所述第二导电胶层1002背向所述主体层1005的表面构成所述基层的第二表面102。主体层1005、第一导电胶层1001、第二导电胶层1002的厚度分别为6μm、2μm和2μm。
对比例1
对比例1的导电膜由单层厚度200μm多孔层构成。其制备方法如下：
(1)提供厚度为200μm的Mn 75Cu 25箔材，其成分为(Cu,γMn)相的单相合金(简称γ单相合金)。
(2)将上述Mn 75Cu 25箔材进行分相热处理，热处理温度为650℃，热处理时间为4h，得到α/γ双相合金产品。
(3)将上一步产物置于足量的2.38mol/L的HCl水溶液中，在25℃进行自由腐蚀脱合金，待溶液中无明显气泡逸出时，取出脱合金后的箔材，即得到对比例1的导电膜。
对比例2
对比例2的导电膜为市售的单层泡沫铜，厚度120μm，孔隙率80％，平均孔径400μm，孔径分布区间为300μm-500μm。
结构和性能分析
1、孔体积
根据合金铸锭原始成分和热处理工艺，并结合图6示出的Cu-Mn合金相图，基于以下公式，能够合理地推导出多孔铜中大孔的总孔体积占多孔铜表观体积的百分比(V 1/V)，多孔铜中小孔的总孔体积占多孔铜表观体积的百分比(V 2/V)，大孔和小孔的总孔体积占多孔铜表观体积的百分比((V 1+V 2)/V)，结果详见表1。
考虑到在脱合金过程中Mn-Cu合金进行了充分的脱合金，因此可以合理地推知Mn-Cu合金中的锰元素被全部脱除。Mn-Cu多相合金的αMn相中的锰元素被全部脱除后，αMn相消失，在αMn相的位置上对应地形成了具有第一孔径的孔(简称大孔)结构。Mn-Cu多 相合金的(Cu,γMn)相中的锰元素被脱除后，(Cu,γMn)相的锰金属消失，但铜金属得以保留，在(Cu,γMn)相上对应地形成了具有第二孔径的孔(简称小孔)结构。上述大孔结构和小孔结构共同地构成多孔铜的多级多孔结构。
以多孔铜的表观体积为V，大孔的孔体积占比(V 1/V)和小孔的孔体积占比(V 2/V)可以通过下式计算：
Figure PCTCN2022117038-appb-000001
Figure PCTCN2022117038-appb-000002
x为合金前驱体中的Mn含量(at.％)；
x γ为(Cu,γMn)相中的Mn含量(at.％)；
1.045为Mn:Cu原子体积比。
上述各例子中多孔铜的大孔孔体积和小孔孔体积如表1所示。
2、孔的比表面积
另外，多孔铜的总比表面积为S(单位m 2/g)，其中大孔的总比表面积为S 1，小孔的总比表面积为S 2。大孔的总比表面积(S 1)和小孔的总比表面积(S 2)的值分别参考文献Celal Soyarslan,et al.,Acta Materialia,(2018),149,326.中提供的计算公式和方法获得。总比表面积S＝S 1+S 2。相关结果如下表3所示
大孔的总比表面积S 1的计算公式如下
Figure PCTCN2022117038-appb-000003
C 1为经验常数，取值参照下表3；
Ψ 1为大孔体积分数V 1/V，取值参照表1；
L 1为形成大孔结构的棱丝的平均直径；
ρ Cu为铜的密度，其值为8.9g/cm 3；
p为合金中锰元素的原子占比；
V为1cm 3。
小孔的总比表面积S 2的计算公式如下：
Figure PCTCN2022117038-appb-000004
C 2为经验常数，取值参照下表1；
Ψ 2为小孔体积分数V 2/V，取值参照表1；
L 2为形成小孔结构的棱丝的平均直径；
ρ Cu为铜的密度，其值为8.9g/cm 3；
p为合金中锰元素的原子占比；
V为1cm 3。
上述各例子中多孔铜的大孔的总比表面积和小孔的总比表面积如表1所示。
3、孔径和棱丝直径
从扫描电子显微镜照片上选取50-100个大孔和50-100个小孔，分别测量大孔和小孔的孔径和棱丝直径，分别计算平均值，结果参见表1。
4、抗拉强度
导电膜、原料基层的拉伸强度可以通过如下方法测试获得。
采用电子式万能试验机，型号CZ-8010，测试方法：将样品(待测的导电膜或原料基层)才切成18mm*100mm的尺寸备用，测试时将样品的两端分别夹持到万能试验机的两个夹头上，将速度设置为5mm/min，进行拉伸测试。拉伸强度的计算公式如下：
σ＝P b/A 0
P b是试样拉断时所承受的最大力，N(牛顿)；
A 0是试样原始横截面积，mm 2；
σ是拉伸强度，单位N/mm 2。
结果如表1所示。
5、二次电池循环测试
(1)以实施例2和对比例2的导电膜作为电极(集流体)，按照以下方法分别组装二次电池，二次电池包括相对设置的第一电极和第二电极：
第一电极采用铝箔作为集流体，集流体表面涂覆有正极活性材料钴酸锂(Dv50为8.1μm)。第一电极的尺寸为φ16mm，活性材料的负载量为0.169mg/mm 2；
第二电极采用本专利提到的导电膜，尺寸φ18mm；
隔膜采用聚乙烯隔离膜，尺寸φ20mm；
电解液采用1mol/L的六氟磷酸锂溶于碳酸乙烯酯-二甲基碳酸酯(体积比为1：1)的溶液；
采用CR2032型号的纽扣电池壳，在手套箱内完成二次电池组装。
(2)电池测试参数如下：
(1)充放电截止电压为2.8～4.2V；
(2)充放电电流为1mA/cm 2。
二次电池的容量-循环圈数测试结果如下表2所示。图8示出二次电池的容量-循环圈 数曲线。
Figure PCTCN2022117038-appb-000005
Figure PCTCN2022117038-appb-000006
实施例1-16的导电膜具有基层与多孔层的层叠结合结构，导电膜表现出让人满意的拉伸强度。具有良好拉伸强度的基层起到了承载多孔层的作用，为多孔层提供了稳定的基体。导电膜整体的力学性能得到了改善，进而能够在二次电池中发挥作用，改善二次电池的容量、循环性能、倍率性能等一项或多相性能。对比例1的导电膜仅由单层多孔层结构，其质脆易碎，强度过低，不能在拉伸测试中获得有效数据。
实施例1-16的导电膜作为二次电池的电极或集流体，作用原理如下：具有第一孔径的孔和第二孔径的孔。具有第一孔径的孔(简称大孔)的内壁可作为活性物质沉积的基底；此外，大孔的另一个作用是提供电解液浸润通道。具有第二孔径的孔(简称小孔)的内壁可作为活性物质沉积的基底。小孔提高了材料的比表面积，从而使多孔导电材料能装载更多的活性物质；此外，小孔的另一个作用是作为活性物质沉积的模板。具体来讲，受小孔尺寸的限制，沉积在小孔中的活性物质的具有纳米级尺寸，纳米级的活性物质因尺寸小而具有较高的离子电导率，进而能够提高电极整体的离子电导率，进而能够改善电池的倍率性能，最终在整体上提高电池的容量、循环稳定性以及倍率性能；此外，小孔的另一个作用是限制活性材料的体积膨胀，避免其粉化失效。
对比例2的导电膜仅具有单一的孔径分布，孔径分布区间为300μm-500μm。如表2所示，实施例2与对比例2的导电膜用于二次电池，实施例2的二次电池表现出提高的比容量(150mAh)和循环保持率(77周循环后保留87％)。对比例2的二次电池表现出低的比容量(146mAh)和循环保持率(77周循环后保留77％)。
需要说明的是，本申请不限定于上述实施方式。上述实施方式仅为示例，在本申请的技术方案范围内具有与技术思想实质相同的构成、发挥相同作用效果的实施方式均包含在本申请的技术范围内。此外，在不脱离本申请主旨的范围内，对实施方式施加本领域技术人员能够想到的各种变形、将实施方式中的一部分构成要素加以组合而构筑的其它方式也包含在本申请的范围内。

Claims (21)

  1. 一种导电膜，所述导电膜包括：
    基层，所述基层具有相对设置的第一表面和第二表面，所述基层具有致密结构；
    第一多孔层，所述第一多孔层层叠结合于所述基层的第一表面；
    所述第一多孔层的包括多孔导电材料；
    所述多孔导电材料具有第一孔径的孔和第二孔径的孔；
    所述第一孔径为n微米，0.5≤n≤10；
    所述第二孔径为m纳米，20＜m＜200。
  2. 根据权利要求1所述的导电膜，所述导电膜还包括：
    第二多孔层，所述第二多孔层层叠结合于所述基层的第二表面；
    所述第一多孔层和所述第二多孔层各自独立地包括多孔导电材料；
    所述多孔导电材料具有第一孔径的孔和第二孔径的孔；
    所述第一孔径为n微米，0.5≤n≤10；
    所述第二孔径为m纳米，20＜m＜200。
  3. 根据权利要求1-2任一项所述的导电膜，其中，所述多孔导电材料的表观体积为V，所述具有第一孔径的孔的总孔体积V 1，所述具有第二孔径的孔的总孔体积为V 2，所述多孔导电材料满足以下关系：
    (V 1+V 2)/V＝60％-90％。
  4. 根据权利要求1-3任一项所述的导电膜，其中，所述多孔导电材料的表观体积为V，所述具有第一孔径的孔的总孔体积V 1，所述多孔导电材料满足以下关系：
    V 1/V＝5％-70％。
  5. 根据权利要求1-4任一项所述的导电膜，其中，所述多孔导电材料的表观体积为V，所述具有第二孔径的孔的总孔体积为V 2，所述多孔导电材料满足以下关系：
    V 2/V＝15％-70％。
  6. 根据权利要求1-5任一项所述的导电膜，其具有以下一项或多项特征：
    (1)相邻的具有第一孔径的孔之间被第一棱丝间隔，第一棱丝的平均棱径为0.89μm-3μm；
    (2)相邻的具有第二孔径的孔之间被第二棱丝间隔，第二棱丝的平均棱径为27nm-100nm。
  7. 根据权利要求1-5任一项所述的导电膜，其具有以下一项或多项特征：
    (1)所述具有第一孔径的孔的总比表面积为0.08-1.32m 2/g；
    (2)所述具有第二孔径的孔的总比表面积为0.87-5.25m 2/g；
    (3)所述多孔导电材料的比表面积为0.95-6.57m 2/g。
  8. 根据权利要求1-7任一项所述的导电膜，其具有以下一项或多项特征：
    (1)基层的厚度为4.5μm-12μm；
    (2)第一多孔层的厚度为50-200μm。
  9. 根据权利要求2-8任一项所述的导电膜，其具有以下一项或多项特征：
    (1)基层的厚度为4.5μm-12μm；
    (2)第一多孔层的厚度为50-200μm；
    (3)第二多孔层的厚度为50-200μm。
  10. 根据权利要求1-9任一项所述的导电膜，所述多孔导电材料的材质为含有M元素的金属单质或合金，M元素选自铜、铝或其组合。
  11. 根据权利要求1-10任一项所述的导电膜，其具有以下一项或多项特征：
    (1)所述基层具有330N/m 2以上的抗拉强度；
    (2)所述导电膜具有100N/m 2以上的抗拉强度。
  12. 根据权利要求1-11任一项所述的导电膜，所述基层具有单层结构或多层结构。
  13. 根据权利要求1-11任一项所述的导电膜，其中，所述基层具有多层结构，所述基层包括主体层和层叠在所述主体层一侧表面的第一导电胶层，所述第一导电胶层背向所述主体层的表面构成所述基层的第一表面。
  14. 根据权利要求2-11任一项所述的导电膜，其中，所述基层具有多层结构，所述基层包括主体层和分别层叠在所述主体层相对两侧表面的第一导电胶层和第二导电胶层，所述第一导电胶层背向所述主体层的表面构成所述基层的第一表面，所述第二导电胶层背向所述主体层的表面构成所述基层的第二表面。
  15. 一种导电膜的制备方法，所述导电膜的定义如权利要求1-14任一项所述，所述制备方法包括：
    (1)提供第一原料多层体，所述第一原料多层体包括：
    原料基层，所述原料基层具有相对设置的第一表面和第二表面，原料基层具有致密结构；
    第一A合金层，所述第一A合金层层叠结合于所述原料基层的第一表面，所述第一A合金层的材质为多相合金，所述多相合金含有αMn相和(M,γMn)相，M元素选自铜、铝或其组合；以及
    可选地，第一B合金层，所述第一B合金层层叠结合于所述原料基层的第二表面，所述第一B合金层的材质为多相合金，所述多相合金含有αMn相和(M,γMn)相，M元素选自铜、铝或其组合；
    (2)采用脱合金化的方法从所述多相合金的αMn相去除至少部分Mn元素，以及从所述多相合金的(M,γMn)相去除至少部分Mn元素；
    其中，所述原料基层被配置为在所述脱合金处理的过程中保持完整。
  16. 根据权利要求15所述的方法，还包括制备第一原料多层体的步骤，具体包括：
    (1)提供第二原料多层体，所述第二原料多层体包括：
    原料基层，所述原料基层具有相对设置的第一表面和第二表面，原料基层具有致密结构；和
    第二A合金层，所述第二A合金层层叠结合于所述原料基层的第一表面，所述第二A合金层中(M,γMn)相的含量为95vol％以上；以及
    可选地，第二B合金层，所述第二B合金层层叠结合于所述原料基层的第一表面，所述第二B合金层中(M,γMn)相的含量为95vol％以上；
    (2)对上一步产物进行分相热处理，在第二A合金层和/或第二B合金层中形成多相合金，所述多相合金含有αMn相和(M,γMn)相，获得第一原料多层体。
  17. 根据权利要求15所述的方法，还包括制备第一原料多层体的步骤，具体包括：
    (1)提供γ单相合金箔，所述γ单相合金箔中(M,γMn)相的含量为95vol％以上；
    (2)对γ单相合金箔进行分相热处理，获得多相合金箔，所述多相合金箔含有αMn相和(M,γMn)相；
    (3)提供原料基层，所述原料基层包括主体层和层叠在所述主体层一侧表面的第一导电胶层，以及可选地，还包括层叠在所述主体层另一侧表面的第二导电胶层；
    (4)在所述第一导电胶层背向所述原料基层的表面层叠结合多相合金箔，以及可选地，在所述第二导电胶层背向所述原料基层的表面层叠结合多相合金箔。
  18. 根据权利要求16或17所述的方法，其具有以下一项或多项特征：
    (1)所述分相热处理的温度500-700℃；
    (2)所述分相热处理的时间为1-4小时；
    (3)所述分相热处理后采用20-1000℃/s的冷却速度进行冷却。
  19. 一种电极或集流体，包括权利要求1-14任一项所述的导电膜。
  20. 一种二次电池，包括权利要求19所述的电极或集流体；
    可选地，所述二次电池是无负极金属电池；
    可选地，所述二次电池的负极活性材料含有金属或合金。
  21. 一种装置，包括权利要求20所述的二次电池，所述二次电池向所述装置提供电能。
PCT/CN2022/117038 2022-08-01 2022-09-05 导电膜及其制备方法、电极、集流体、二次电池及装置 WO2024026970A1 (zh)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130045427A1 (en) * 2011-08-19 2013-02-21 Nanoteck Instruments, Inc. Prelithiated current collector and secondary lithium cells containing same
CN106159277A (zh) * 2015-04-15 2016-11-23 微宏动力***（湖州）有限公司 多孔集流体及其制备方法
CN108172761A (zh) * 2017-12-30 2018-06-15 中南大学 一种用于锂二次电池的复合负极、及其制备和应用
CN108598490A (zh) * 2018-04-20 2018-09-28 南京邮电大学 一种三维多孔金属负极集流体及其制备方法和应用
CN114023928A (zh) * 2021-08-31 2022-02-08 天津大学 分级多孔铜原位构筑双金属氧化物一体式电极的制备方法
CN114220947A (zh) * 2021-12-09 2022-03-22 厦门大学 一种锂金属电池负极、集流体及其制备方法和电池

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN206921926U (zh) * 2017-07-05 2018-01-23 广东工业大学 一种新型锂离子电池
CN114875264B (zh) * 2021-02-05 2023-05-09 清华大学 三维分级分层多孔铜及其制备方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130045427A1 (en) * 2011-08-19 2013-02-21 Nanoteck Instruments, Inc. Prelithiated current collector and secondary lithium cells containing same
CN106159277A (zh) * 2015-04-15 2016-11-23 微宏动力***（湖州）有限公司 多孔集流体及其制备方法
CN108172761A (zh) * 2017-12-30 2018-06-15 中南大学 一种用于锂二次电池的复合负极、及其制备和应用
CN108598490A (zh) * 2018-04-20 2018-09-28 南京邮电大学 一种三维多孔金属负极集流体及其制备方法和应用
CN114023928A (zh) * 2021-08-31 2022-02-08 天津大学 分级多孔铜原位构筑双金属氧化物一体式电极的制备方法
CN114220947A (zh) * 2021-12-09 2022-03-22 厦门大学 一种锂金属电池负极、集流体及其制备方法和电池

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