CN112133885B - Battery core and secondary battery with three-layer pole piece structure - Google Patents

Battery core and secondary battery with three-layer pole piece structure Download PDF

Info

Publication number
CN112133885B
CN112133885B CN202011021426.7A CN202011021426A CN112133885B CN 112133885 B CN112133885 B CN 112133885B CN 202011021426 A CN202011021426 A CN 202011021426A CN 112133885 B CN112133885 B CN 112133885B
Authority
CN
China
Prior art keywords
pole piece
negative
foil
negative pole
battery
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202011021426.7A
Other languages
Chinese (zh)
Other versions
CN112133885A (en
Inventor
谢呈德
徐建龙
唐永炳
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Real Power Industrial Ltd
Shenzhen Institute of Advanced Technology of CAS
Original Assignee
Real Power Industrial Ltd
Shenzhen Institute of Advanced Technology of CAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Real Power Industrial Ltd, Shenzhen Institute of Advanced Technology of CAS filed Critical Real Power Industrial Ltd
Priority to CN202011021426.7A priority Critical patent/CN112133885B/en
Publication of CN112133885A publication Critical patent/CN112133885A/en
Application granted granted Critical
Publication of CN112133885B publication Critical patent/CN112133885B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/058Construction or manufacture
    • H01M10/0585Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • H01M10/0525Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/13Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/133Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/13Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/134Electrodes based on metals, Si or alloys
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M2004/021Physical characteristics, e.g. porosity, surface area
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M2004/026Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027Negative electrodes
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50Manufacturing or production processes characterised by the final manufactured product

Abstract

The invention discloses a battery core with a three-layer pole piece structure and a secondary battery, and relates to the technical field of lithium batteries. The battery core comprises a positive pole piece, a first negative pole piece, a second negative pole piece and a diaphragm, wherein the battery core has a stacked structure of positive pole piece-diaphragm-first negative pole piece-second negative pole piece-diaphragm-positive pole piece; the lithium releasing and inserting specific capacity of the active material of the first negative pole piece is lower than that of the active material of the second negative pole piece. The novel battery core with the three-layer pole piece structure is designed from the aspect of battery structure design, the high-capacity negative electrode material alloyed with lithium ions can be effectively applied to a battery system, and the energy density, the cycle performance and the safety performance of the battery are effectively improved.

Description

Battery core and secondary battery with three-layer pole piece structure
Technical Field
The invention relates to the technical field of lithium batteries, in particular to a battery core with a three-layer pole piece structure and a secondary battery.
Background
In 2016, Tang Yong Argy researchers and teams thereof in Shenzhen Advanced technology research institute of Chinese academy of sciences make breakthrough progress in the development research of novel efficient batteries, and research results of the Tang Yong Argy researchers and the teams thereof release a brand-new aluminum-graphite double-ion battery technology on Advanced Energy Materials (DOI:10.1002/aenm.201502588) in the Energy material journal, the working principle of the technology is different from that of the existing traditional lithium battery, cheap graphite is used as a positive electrode, and an aluminum foil is simultaneously used as a negative active material and a current collector; in 8 months, a high-rate, long-cycle and high-energy-density bi-ion battery based on a carbon-coated porous aluminum foil negative electrode is published on an Advanced Materials journal (DOI:10.1002/adma.201603735) on line. The research team utilizes the aluminum foil as the negative plate of the novel high-efficiency battery, and the specific energy density of the novel high-efficiency battery system battery is higher and the cost is lower due to the reduction of the traditional negative active material. Therefore, the novel high-efficiency battery has great application prospect. Research teams thereof fully recognize the problems existing when aluminum foil is used as a negative electrode plate, and propose to process the aluminum foil into carbon-coated porous aluminum foil to solve the problems of volume expansion of the aluminum foil and compatibility of electrolyte. The research results show that the solution provided by the research results is capable of effectively solving the problem of aluminum foil as the negative active material. However, since the research team adopts the chemical corrosion method to obtain the porous aluminum foil, the method for processing and preparing the porous aluminum foil enables the aluminum foil to be thin, and the pore size and the pore distribution of the aluminum foil cannot be accurately controlled, so that the consistency of the battery is influenced.
The existing battery structure is a positive electrode and negative electrode two-layer structure, in a traditional lithium ion secondary battery system, positive active materials are coated on two sides of an aluminum foil current collector, negative active materials are coated on two sides of a copper foil current collector, and a positive electrode plate, a diaphragm and a negative electrode plate are assembled into a battery in a winding or laminating mode; in the novel metal foil negative electrode battery system, positive active materials are coated on two sides of an aluminum foil current collector, and a metal foil negative electrode sheet or a metal foil negative electrode sheet subjected to modification treatment and a diaphragm are assembled into a battery in a winding or laminating mode. The structure can cause corresponding problems of the battery due to the problems of the negative pole piece. For example, the conventional graphite negative electrode material has low lithium intercalation capacity and low lithium intercalation potential, so that the battery has the problems of low energy density, potential safety hazard and the like. In the novel metal foil negative electrode battery system, the reason that the volume change of the metal negative electrode material is large in the lithium desorption process leads to the reasons of poor battery cycle performance, poor charging and discharging efficiency and the like.
Disclosure of Invention
The invention aims to solve the technical problems of defects in the background technology and creatively provides a novel battery core with a three-layer electrode structure and a secondary battery so as to solve the problems of high expansion of a metal negative electrode material, low specific capacity of a graphite negative electrode material and easy occurrence of lithium precipitation at a low lithium intercalation potential.
In order to solve the above problems, the present invention proposes the following technical solutions:
a battery core with a three-layer pole piece structure comprises a positive pole piece, a first negative pole piece, a second negative pole piece and a diaphragm, wherein the battery core has a stacked structure of positive pole piece-diaphragm-first negative pole piece-second negative pole piece-diaphragm-positive pole piece; the lithium releasing and inserting specific capacity of the active material of the first negative pole piece is lower than that of the active material of the second negative pole piece.
It is understood that the battery core may be formed by winding or stacking. As is well known to those skilled in the art, stacking: the positive pole piece-diaphragm-first negative pole piece-second negative pole piece-diaphragm-positive pole piece is the cell of the minimum unit. In other embodiments, one skilled in the art may construct the stack as desired: the battery cell is assembled by using the positive pole piece-diaphragm-first negative pole piece-second negative pole piece-diaphragm-positive pole piece- … … -positive pole piece, and the expression "… …" represents a repeating unit of "diaphragm-first negative pole piece-second negative pole piece-diaphragm-positive pole piece", and the invention also falls into the protection scope of the invention.
It is further, first negative pole piece includes first negative pole active material and the first negative pole mass flow body, first negative pole active material evenly covers in the one side of keeping away from the second negative pole piece of the first negative pole mass flow body.
Further, the first negative active material is selected from one or more of artificial graphite, natural modified graphite, soft carbon, hard carbon, carbon nanotubes, graphene, composite graphite, mesophase carbon microspheres and expanded graphite materials.
Further, the first negative current collector is selected from a non-porous copper foil, a non-porous nickel foil, a non-porous iron foil, a non-porous stainless steel foil, a porous copper foil, a porous nickel foil, a porous iron foil, a porous stainless steel foil, a copper mesh, a nickel mesh, an iron mesh, a stainless steel mesh and conductive carbon cloth.
Further, the second negative electrode plate is selected from one of aluminum foil, silicon foil, germanium foil, tin foil, antimony foil and zinc foil; the second negative pole piece comprises a current collector part and an active part, wherein the thickness of the current collector part accounts for 28% -80% of the thickness of the second negative pole piece.
Furthermore, the second negative pole piece comprises a second negative pole active material and a second negative pole current collector, and the second negative pole active material is uniformly coated on one surface, far away from the first negative pole piece, of the second negative pole current collector.
Further, the second cathode active material is one or more of aluminum, silicon, germanium, tin, antimony and zinc or a composite material thereof.
Further, the second negative current collector is selected from a non-porous copper foil, a non-porous nickel foil, a non-porous iron foil, a non-porous stainless steel foil, a porous copper foil, a porous nickel foil, a porous iron foil, a porous stainless steel foil, a copper mesh, a nickel mesh, an iron mesh, a stainless steel mesh and a conductive carbon cloth.
The positive electrode plate comprises an aluminum foil current collector and positive active materials coated on two sides of the aluminum foil current collector, wherein the positive active materials are selected from at least one of lithium iron phosphate, lithium manganese phosphate, lithium cobaltate, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminate, lithium manganate, lithium nickelate, lithium titanate, artificial graphite, natural modified graphite, soft carbon, hard carbon, carbon nanotubes, graphene, composite graphite, mesocarbon microspheres, expanded graphite materials and the like.
The invention also provides a secondary battery, which comprises the battery core with the three-layer pole piece structure.
Compared with the prior art, the invention can achieve the following technical effects:
the novel battery core with the three-layer pole piece structure is designed from the aspect of battery structure design, the high-capacity negative electrode material alloyed with lithium ions can be effectively applied to a battery system, and the energy density, the cycle performance and the safety performance of the battery are effectively improved.
The invention carries out the structural design of the battery when the negative electrode material with high specific capacity and large volume expansion is actually applied for the first time, the design fully considers the functions of the negative electrode plate and the characteristics existing when lithium ions are alloyed with the negative electrode active material, and the application of the alloyed negative electrode material with high specific capacity and large volume expansion in a battery system is expected to be realized through the optimization of the structural design, so the design of the battery core structure with the three layers of the electrode plates is very critical.
The secondary battery with the three-layer battery core structure provided by the invention is simple to manufacture, low in cost and easy for industrial production. Therefore, the secondary battery with the three-layer battery core structure provided by the invention has a commercial prospect.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a battery cell having a three-layer pole piece structure according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a first negative electrode tab of a battery core having a three-layer tab structure according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a second negative electrode tab of a battery core having a three-layer tab structure according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a second negative electrode tab of a battery core having a three-layer tab structure according to another embodiment of the present invention.
Reference numerals
The cathode comprises a cathode pole piece 1, a first cathode pole piece 2, a second cathode pole piece 3, a diaphragm 4, a first cathode active material 21, a first cathode current collector 22, a second cathode active material 31 and a second cathode current collector 32.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, in which like reference numerals represent like elements. It is apparent that the embodiments to be described below are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention has good feasibility after theoretical simulation and experimental verification, and beneficial results are illustrated by the following specific embodiments:
the battery core with the three-layer pole piece structure comprises a positive pole piece 1, a first negative pole piece 2, a second negative pole piece 3 and a diaphragm 4, and the structure of the battery core is shown in figures 1-4.
The positive electrode plate 1 comprises an aluminum foil current collector and positive active materials coated on the two sides of the aluminum foil current collector, wherein the positive active materials are selected from at least one of lithium iron phosphate, lithium manganese phosphate, lithium cobaltate, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium manganese oxide, lithium nickelate, lithium titanate, artificial graphite, natural modified graphite, soft carbon, hard carbon, carbon nano tubes, graphene, composite graphite, mesocarbon microbeads, expanded graphite materials and the like.
The first negative electrode sheet 2 includes a first negative electrode active material 21 and a first negative electrode collector 22, and the first negative electrode active material 21 is uniformly coated on one surface of the first negative electrode collector 22 away from the second negative electrode sheet 3.
In one embodiment, the first negative active material of the first negative electrode plate is one or more of artificial graphite, natural modified graphite, soft carbon, hard carbon, carbon nanotubes, graphene, composite graphite, mesocarbon microbeads, expanded graphite material, and the like.
The first negative current collector is selected from a non-porous copper foil, a non-porous nickel foil, a non-porous iron foil, a non-porous stainless steel foil, a porous copper foil, a porous nickel foil, a porous iron foil, a porous stainless steel foil, a copper net, a nickel net, an iron net, a stainless steel net and conductive carbon cloth.
Referring to fig. 3, in an embodiment, the second negative electrode tab 3 is selected from one of aluminum foil, silicon foil, germanium foil, tin foil, antimony foil, and zinc foil, which is a negative electrode foil material that can be alloyed with lithium. At this time, the second negative electrode tab includes a current collector portion and an active portion, wherein the thickness of the current collector portion accounts for 28% -80% of the thickness of the second negative electrode tab.
It is to be understood that the collector portion is a structure for collecting current, and the active portion is a structure for participating in generation of current.
Referring to fig. 4, in another embodiment, the second negative electrode tab 3 includes a second negative active material 31 and a second negative current collector 32, and the second negative active material 31 is uniformly coated on a surface of the second negative current collector 32 away from the first negative electrode tab 2.
The second negative electrode active material is coated or deposited on the second negative electrode current collector (inactive metal foil).
The second cathode active material is one or more of aluminum, silicon, germanium, tin, antimony and zinc or a composite material thereof.
The second negative current collector is an inactive metal foil.
The battery core with the three-layer pole piece structure provided by the invention comprises two positive pole pieces 1, a first negative pole piece 2, a second negative pole piece 3 and two diaphragms 4; the positive pole piece 1 is a positive active material coated on two surfaces of a metal aluminum foil; the first negative active material 21 is coated on one face of the first negative current collector 22 as a first negative electrode tab 2; a metal foil alloyable with lithium is used as the second negative electrode tab 3, or a second negative active material 31 alloyable with lithium is coated and deposited on one side of the second negative current collector 32 as the second negative electrode tab 3. According to the method, when a positive pole piece 1-a diaphragm 4-a first negative pole piece 2-a second negative pole piece 4-a diaphragm 4-a positive pole piece 1 are stacked together to form an integral battery core, and the first negative pole piece 2 and the second negative pole piece 3 are stacked, the stacking mode needs to ensure that the corresponding surfaces of the first negative pole piece 2, the second negative pole piece 3 and the positive pole piece 1 are active surfaces capable of participating in reaction.
Therefore, the battery core with the three-layer pole piece structure provided by the invention has the advantages of a metal foil negative electrode and a graphite negative electrode, and simultaneously effectively solves the problems of high expansion of a metal negative electrode material, low specific capacity of the graphite negative electrode material and easy occurrence of lithium precipitation at low lithium intercalation potential, so that the battery with the battery core with the three-layer pole piece structure has the performances of high energy density, high safety, long cycle and the like. By arranging two negative pole pieces made of different materials, the use amount of the negative pole material is reduced by utilizing the characteristic of high specific capacity of the negative pole materials such as metal aluminum and the like, and the metal foils such as aluminum foil, copper foil and the like have excellent electric and heat conducting performance and surface contact of the metal foils and the copper foil and the like, and the contact of the active materials and the current collector has better electric and heat conducting capacity, so that the impedance of the battery is reduced, and the thermal diffusion capacity of the battery is enhanced; meanwhile, the characteristics of low volume change and high interface stability of the graphite negative electrode material in the lithium desorption and insertion process are utilized, and the cycle performance and the charge and discharge efficiency of the battery are improved.
The secondary battery provided by the invention comprises the battery core with the three-layer pole piece structure. The preparation method can adopt various methods known to those skilled in the art, and for example, the method can comprise the following steps:
(1) preparing a positive pole piece: preparing a positive active material into slurry, coating the slurry on two sides of an aluminum foil current collector, and preparing a positive pole piece;
(2) preparing a first negative pole piece: preparing a first negative active material (carbon material or carbon composite material) into slurry, and coating the slurry on one surface of a first negative current collector to prepare a first negative pole piece;
(3) selecting a material capable of alloying with lithium ions as a second negative pole piece;
(3) packaging: and (3) sequentially laminating or winding the positive pole piece, the first negative pole piece, the second negative pole piece and the diaphragm according to the laminated structure shown in the figure 1 to prepare a battery core, and packaging the battery core.
The packaging of the present invention includes placing the battery core into the battery case, welding the cover plate and the battery case, injecting the electrolyte into the battery case, forming and sealing the battery, and the forming, sealing and other techniques are various techniques known to those skilled in the art, and the present invention is not particularly limited. The present invention, such as a positive electrode current collector, a positive electrode slurry, an electrolyte, and a separator of a secondary battery, is not particularly limited, and various positive electrode current collectors, positive electrode slurries, electrolytes, and separators known to those skilled in the art can be used.
The present invention will be described in further detail with reference to specific embodiments, which are described herein for the purpose of illustration only and are not to be construed as limiting the invention. The raw materials used in the examples and comparative examples were obtained commercially.
Example 1: battery core and secondary battery of three-layer pole piece structure based on aluminum foil
The positive active material is lithium iron phosphate; the first negative active material is an artificial graphite material; the second negative pole piece is an aluminum foil with the thickness of 30 microns, the thickness of the active part accounts for 50%, and the thickness of the current collector part accounts for 50%.
The preparation method comprises the steps of coating a lithium iron phosphate positive electrode material with the specific capacity of 140mAh/g, PVDF and conductive carbon black on a double-sided aluminum foil according to the mass ratio of 95:3:2 to serve as a positive electrode piece; the artificial graphite negative electrode material with the specific capacity of 340mAh/g, SBR, CMC and conductive carbon black are coated on a single-sided copper foil according to the mass ratio of 95:2.5:1.5:1 to serve as a first negative electrode piece. The processing technology and the process control of the positive and negative pole pieces adopt the current industrialized technology, and finally, the processed positive pole piece, the first negative pole piece, the second negative pole piece and the electrolyte (1mol/L LiPF) 6 A mixed solution (volume ratio: 1) of Ethylene Carbonate (EC) and dimethyl carbonate (DMC), and a separator (celgard2400 polypropylene porous membrane) were assembled into a full cell in a glove box filled with argon gas to obtain a battery sample C1.
To illustrate the beneficial effects of this example, we fabricated a cell using a conventional two-layer electrode structure, and the specific fabrication process was as in comparative example 1 and comparative example 2.
Comparative example 1
The positive active material is lithium iron phosphate, and the negative active material of the negative pole piece is an artificial graphite material.
The preparation method comprises the following steps: coating a lithium iron phosphate positive active material with the specific capacity of 140mAh/g, PVDF and conductive carbon black on a double-sided aluminum foil according to the mass ratio of 95:3:2 to serve as a positive pole piece; the artificial graphite negative electrode material with the specific capacity of 340mAh/g, SBR, CMC and conductive carbon black are coated on double-sided copper foil as a first negative electrode piece according to the mass ratio of 95:2.5:1.5: 1. The processing technology and process control of the positive and negative pole pieces adopt the current industrialized technology, and finally, the processed negative pole piece, positive pole piece and electrolyte (1 mol/L) LiPF 6 A mixed solution (volume ratio: 1) of Ethylene Carbonate (EC) and dimethyl carbonate (DMC), and a separator (celgard2400 polypropylene porous membrane) were assembled into a full cell in a glove box filled with argon gas to obtain a battery sample C00.
Comparative example 2
The positive active material is lithium iron phosphate; the negative pole piece is an aluminum foil with the thickness of 60 microns, the thickness of the active part accounts for 50%, and the thickness of the current collector part accounts for 50%.
The preparation method comprises the step of coating the lithium iron phosphate positive active material with the specific capacity of 140mAh/g, PVDF and conductive carbon black on a double-sided aluminum foil according to the mass ratio of 95:3:2 to serve as a positive pole piece. The processing technology and process control of the positive and negative pole pieces adopt the current industrialized technology, and finally, the processed positive pole piece, negative pole piece and electrolyte (1mol/L LiPF) 6 A mixed solution (volume ratio: 1) of Ethylene Carbonate (EC) and dimethyl carbonate (DMC), and a separator (celgard2400 polypropylene porous membrane) were assembled into a full cell in a glove box filled with argon gas to obtain a battery sample C01.
The battery cells of the above examples were subjected to charge/discharge tests at a voltage range of 2.5 to 3.65V with a charge/discharge rate of 0.2C, and the test results are as follows.
TABLE 1 Battery test data for inventive example 1 and comparative examples 1-2
Battery sample First efficiency of cell (%) Battery energy density (Wh/L) Capacity retention (%) at 500 weeks of circulation
C1 89 576.5 92.3
C00 91.2 502.0 96.5
C01 87.5 631.0 85.2
According to the test result, the battery core with the novel three-layer pole piece structure provided by the invention is intuitively displayed to effectively integrate two negative electrode materials, and the advantages of the two negative electrode materials are fully exerted, so that the effects of improving the advantages and avoiding the disadvantages are achieved.
Examples 2 to 13: the influence of the thickness of the active part of the second negative electrode plate in the battery core of the three-layer electrode plate structure based on the aluminum foil on the lithium battery is explored
Examples 2 to 13 are different from example 1 in that the ratio of the thickness of the active portion of the aluminum foil in the second negative electrode sheet is different, the steps of preparing the positive electrode sheet, the first negative electrode sheet, the electrolyte and the battery are the same, and the ratio of the thickness of the active portion of the aluminum foil in the second negative electrode sheet is in the range of 20% to 72%.
The batteries of examples 2-13 were tested for charge and discharge at a charge and discharge rate of 0.2C and a voltage range of 2.5-3.65V, and compared with example 1, the results were as follows:
TABLE 2 Battery test data for inventive examples 1-13
Figure BDA0002696693600000081
Figure BDA0002696693600000091
Examples 14 to 25: the influence of the thickness of a second negative electrode plate in a battery core of a three-layer electrode plate structure based on an aluminum foil on a lithium battery is explored
Examples 14-25 differ from example 1 in the thickness of the aluminum foil in the second negative electrode tab; the thickness of the active part accounts for 50% of the thickness of the second negative pole piece, and the preparation steps of the positive pole, the first negative pole piece, the electrolyte and the battery are the same.
The batteries of examples 14 to 25 were subjected to charge and discharge tests at a charge and discharge rate of 0.2C and a voltage range of 2.5 to 3.65V, and compared with example 1, the test results were as follows:
TABLE 3 test data for batteries of inventive examples 1 and 14-25
Figure BDA0002696693600000092
Figure BDA0002696693600000101
Examples 26 to 37: the influence of the battery core with the three-layer pole piece structure based on different first negative active materials on the lithium battery is researched
Examples 26 to 37 differ from example 1 in the kind of the substance used for the first negative electrode active material of the first negative electrode tab, and the positive electrode, the second negative electrode tab, the electrolyte and the battery preparation steps were the same.
The batteries of examples 26 to 37 were subjected to the charge and discharge test at a charge and discharge rate of 0.2C and a voltage range of 2.5 to 3.65V, and compared with example 1, the test results were as follows:
TABLE 3 test data for batteries of inventive examples 1 and 26-37
Figure BDA0002696693600000102
Figure BDA0002696693600000111
Examples 38 to 49: influence of battery core of three-layer pole piece structure based on different first negative current collectors on lithium battery is explored
Examples 38-49 differ from example 1 in that the first negative current collector is different and the positive electrode, first negative active material, second negative electrode tab, electrolyte and battery preparation steps are the same.
The batteries of examples 38 to 49 were subjected to the charge and discharge test at a charge and discharge rate of 0.2C and a voltage range of 2.5 to 3.65V, and compared with example 1, the test results were as follows:
TABLE 4 test data for batteries of examples 1 and 38-49 of the present invention
Figure BDA0002696693600000112
Examples 50 to 70: the influence of a battery core with a three-layer pole piece structure based on different anode active materials on a lithium battery is explored
Examples 50 to 70 are different from example 1 in the kind of the positive electrode active material in the positive electrode sheet, and when the positive electrode active material in the positive electrode sheet contains a metal element, the method and the steps for preparing the positive electrode sheet are the same as those in example 1; the corresponding steps of preparing the first negative electrode plate, the second negative electrode plate, the electrolyte and the battery are also the same as those of the embodiment 1. When the positive active material in the positive electrode plate is a carbon material, the preparation methods and the steps of the positive electrode plate and the electrolyte are the same as those of the comparative example 3; the corresponding first negative electrode tab, second negative electrode tab, and battery preparation steps were also the same as in comparative example 3.
Comparative example 3
The positive active material is mesocarbon microbeads; the negative pole piece is an aluminum foil with the thickness of 60 microns, and the thickness of the active part accounts for 50 percent. The mesophase carbon microsphere positive electrode material with the specific capacity of 100mAh/g, PVDF and conductive carbon black are coated on a double-sided aluminum foil as a positive electrode piece according to the mass ratio of 95:3: 2. The processing technology and the process control of the positive and negative pole pieces adopt the current industrialized technology, and finally, the processed negative pole piece, the positive pole piece, the electrolyte (the volume ratio of 1: 1) of the mixed solution of Ethylene Carbonate (EC) and dimethyl carbonate (DMC) of 1mol/L LiPF 6) and the diaphragm (celgard2400 polypropylene porous membrane) are assembled into a full cell in a glove box filled with argon to obtain a cell sample C03.
The batteries of examples 50-59 were tested for charge and discharge at a charge and discharge rate of 0.2C, in a voltage range of 2.75-4.2V for examples other than the charge and discharge voltage range of 0.1-2.0V for example 53, and compared with example 1; the batteries of examples 60 to 70 and C003 were subjected to the charge/discharge test at a charge/discharge rate of 0.2C and a voltage range of 3.0 to 4.6V. The test results were as follows:
TABLE 5 Battery test data for inventive examples 1 and examples 50-70 and comparative example C03
Figure BDA0002696693600000121
Figure BDA0002696693600000131
Examples 71 to 76: the influence of the battery core with the three-layer pole piece structure of the second negative pole piece based on different foils on the lithium battery is explored
Examples 71-76 differ from example 1 in the type of foil used for the second negative electrode sheet, and the positive electrode, the active material of the first negative electrode sheet, the electrolyte, and the cell preparation steps were the same.
The electrochemical performance of the batteries of examples 71-76 was tested under the conditions of a test magnification of 0.2C and a voltage range of 2.75-4.2V. And compared to example 1, the test results are as follows:
TABLE 6 Battery test data for inventive examples 1 and 71-76
Figure BDA0002696693600000132
Figure BDA0002696693600000141
Examples 77 to 96: the influence of the battery core with the three-layer pole piece structure based on the second cathode active materials of different types on the lithium battery is researched
Examples 77 to 96 differ from example 1 in that the second negative electrode tab includes a second negative electrode active material and a second negative electrode current collector. The second negative electrode active material is a high-capacity negative electrode active material layer, the active material layer participating in the reaction thickness (15um) is kept constant, and the active material layer is formed by coating negative electrode active material particles on a non-active foil copper or depositing an active material on the non-active foil copper in a deposition mode. The second negative active material of the alloy group is silicon, germanium, tin, lead, aluminum, antimony, bismuth, zinc, an aluminum-copper alloy, a copper-tin alloy, an aluminum-silicon alloy, an aluminum-magnesium alloy, a tin-nickel alloy, a tin-cobalt-nickel alloy, a tin-nickel-carbon alloy, or the like.
The electrochemical performance of the composite negative electrode of example 77-96 was tested under the conditions of a test magnification of 0.2C and a voltage range of 2.75-4.2V. And compared to example 1, the test results are as follows:
TABLE 7 Battery test data for inventive examples 1 and 77-96
Figure BDA0002696693600000142
Figure BDA0002696693600000151
Figure BDA0002696693600000161
Examples 97 to 121: influence of battery core of three-layer pole piece structure of second negative pole piece based on different current collectors on lithium battery is explored
Examples 97-121 differ from example 83 in that the second negative electrode active material was coated onto or deposited by deposition onto a different non-active foil, and the positive electrode, first negative electrode sheet active material, electrolyte and cell preparation steps were the same.
The electrochemical performance of the composite negative electrode of example 97-121 was tested under the conditions of a test magnification of 0.2C and a voltage range of 2.75-4.2V. And compared with example 1 and example 83, the test results are as follows:
TABLE 8 Battery test data for inventive examples 1, 83 and 97-121
Figure BDA0002696693600000162
Figure BDA0002696693600000171
In conclusion, the battery core with the three-layer pole piece structure provided by the invention can directly adopt the aluminum foil as the negative pole piece layer, can adjust the sizes of the positive and negative pole types according to the type and the capacity of the battery, and can manufacture uniform batteries, so that the consistency of the batteries, the electrical performance and the safety performance of the batteries are kept, and the batteries meet the requirements of customers. In addition, the battery core with the three-layer pole piece structure is manufactured into a lithium battery, is simple to manufacture, has low cost and is easy for industrial production. Therefore, the lithium battery with the battery core of the three-layer pole piece structure has a commercial prospect.
In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.
While the invention has been described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (2)

1. A battery core with a three-layer pole piece structure is characterized by comprising a positive pole piece, a first negative pole piece, a second negative pole piece and a diaphragm, wherein the battery core has a stacked structure of positive pole piece-diaphragm-first negative pole piece-second negative pole piece-diaphragm-positive pole piece; the lithium releasing and inserting specific capacity of the active material of the first negative pole piece is lower than that of the active material of the second negative pole piece;
the first negative pole piece comprises a first negative active material and a first negative current collector, and the first negative active material is uniformly coated on one surface of the first negative current collector, which is far away from the second negative pole piece;
the positive electrode plate comprises an aluminum foil current collector and positive active materials coated on the two sides of the aluminum foil current collector, wherein the positive active materials are selected from at least one of lithium iron phosphate, lithium manganese phosphate, lithium cobaltate, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium manganese oxide, lithium nickelate, lithium titanate, artificial graphite, natural modified graphite, soft carbon, hard carbon, carbon nano tubes, graphene, composite graphite, mesocarbon microbeads and expanded graphite materials;
the first negative active material is selected from one or more of artificial graphite, natural modified graphite, soft carbon, hard carbon, carbon nanotubes, graphene, composite graphite, mesocarbon microbeads and expanded graphite materials;
the first negative current collector is selected from one of nonporous copper foil, nonporous nickel foil, nonporous iron foil, nonporous stainless steel foil, porous copper foil, porous nickel foil, porous iron foil, porous stainless steel foil, copper mesh, nickel mesh, iron mesh, stainless steel mesh and conductive carbon cloth;
the second negative pole piece is selected from one of aluminum foil, germanium foil and tin foil; the second negative pole piece comprises a current collector part and an active part, wherein the thickness of the current collector part accounts for 28% -80% of that of the second negative pole piece; the thickness of the second negative pole piece is 25-70 μm.
2. A secondary battery comprising a battery cell of the three-layer pole piece structure of claim 1.
CN202011021426.7A 2020-09-23 2020-09-23 Battery core and secondary battery with three-layer pole piece structure Active CN112133885B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011021426.7A CN112133885B (en) 2020-09-23 2020-09-23 Battery core and secondary battery with three-layer pole piece structure

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011021426.7A CN112133885B (en) 2020-09-23 2020-09-23 Battery core and secondary battery with three-layer pole piece structure

Publications (2)

Publication Number Publication Date
CN112133885A CN112133885A (en) 2020-12-25
CN112133885B true CN112133885B (en) 2022-08-12

Family

ID=73840644

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011021426.7A Active CN112133885B (en) 2020-09-23 2020-09-23 Battery core and secondary battery with three-layer pole piece structure

Country Status (1)

Country Link
CN (1) CN112133885B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113299878B (en) * 2021-05-21 2023-12-19 珠海冠宇电池股份有限公司 Negative plate and application thereof
CN113270568A (en) * 2021-05-27 2021-08-17 珠海冠宇电池股份有限公司 Battery core and battery
CN116632368B (en) * 2023-07-21 2023-11-14 宁德新能源科技有限公司 Secondary battery and electronic device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103700808A (en) * 2013-06-09 2014-04-02 洛阳月星新能源科技有限公司 Lithium ion battery composite anode pole piece, preparation method and lithium ion battery
CN105406131A (en) * 2015-11-30 2016-03-16 李朝 Capacitive type lithium-ion power battery with hybrid negative electrode plates
CN106025361A (en) * 2016-05-27 2016-10-12 山东精工电子科技有限公司 Low-temperature lithium ion battery
CN108470942A (en) * 2018-03-05 2018-08-31 孙备宽 A kind of high-efficiency battery with three layers of electrode structure

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103700808A (en) * 2013-06-09 2014-04-02 洛阳月星新能源科技有限公司 Lithium ion battery composite anode pole piece, preparation method and lithium ion battery
CN105406131A (en) * 2015-11-30 2016-03-16 李朝 Capacitive type lithium-ion power battery with hybrid negative electrode plates
CN106025361A (en) * 2016-05-27 2016-10-12 山东精工电子科技有限公司 Low-temperature lithium ion battery
CN108470942A (en) * 2018-03-05 2018-08-31 孙备宽 A kind of high-efficiency battery with three layers of electrode structure

Also Published As

Publication number Publication date
CN112133885A (en) 2020-12-25

Similar Documents

Publication Publication Date Title
CN111969214B (en) Positive plate with special-shaped structure and lithium ion battery comprising positive plate
CN112133885B (en) Battery core and secondary battery with three-layer pole piece structure
WO2021223655A1 (en) Positive electrode plate, preparation method therefor, and lithium ion battery comprising same
CN207368126U (en) The lithium ion battery of lithium is mended based on porous lithium metal
CN112825354B (en) Lithium negative electrode, preparation method thereof and lithium secondary battery
CN111129428A (en) Multilayer positive plate electrode structure, preparation method thereof and positive and negative battery structure
CN111916757B (en) Multilayer electrode, preparation method of multilayer electrode and lithium ion battery
CN113675365B (en) Negative plate and lithium ion battery
CN212907803U (en) Lithium ion battery with high-rate charge and discharge
CN112542565A (en) Negative plate for improving quick charge capacity of lithium ion battery and preparation method and application thereof
CN112599760A (en) Metal type negative electrode slurry, negative electrode plate and secondary battery
CN103035925A (en) Lithium-ion power battery, lithium-ion power battery current collecting body, negative electrode pole piece
CN116093247A (en) Pole piece and lithium ion battery
CN105870489B (en) Monomer-polymer lithium ion battery manufacturing method and its assemble method
CN214336748U (en) Prussian blue sodium ion battery
CN114242932A (en) Lithium ion battery
CN110600285B (en) Lithium separation-free pre-lithium intercalation method for cathode of lithium ion electrochemical energy storage device
CN112234247A (en) Lithium ion battery
CN116344742A (en) Fully lithiated negative electrode plate and preparation method thereof
CN112542572A (en) Novel lithium ion battery positive pole piece and preparation method and application thereof
CN212182476U (en) High-energy-density and high-power-density aluminum ion battery
CN115621532A (en) Secondary battery and power consumption device
CN105914322B (en) The manufacturing method of monomer high capacity polymer lithium ion battery
CN111834637B (en) Flexible lithium ion battery with multi-channel flexible current collector structure for reducing internal resistance and preparation method thereof
CN112864374B (en) Lithium cathode with gradient distribution of lithium content, preparation method thereof and lithium secondary battery

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
TA01 Transfer of patent application right

Effective date of registration: 20210114

Address after: 518000 A9 808, Tian Liao Industrial Zone, Xue Yuan Avenue, Taoyuan street, Shenzhen, Guangdong, China. 808

Applicant after: REAL POWER INDUSTRIAL Ltd.

Applicant after: SHENZHEN INSTITUTES OF ADVANCED TECHNOLOGY

Address before: 518000 A9 808, Tian Liao Industrial Zone, Xue Yuan Avenue, Taoyuan street, Shenzhen, Guangdong, China. 808

Applicant before: REAL POWER INDUSTRIAL Ltd.

TA01 Transfer of patent application right
GR01 Patent grant
GR01 Patent grant