CN115189038A

CN115189038A - Electrode pole piece unit, electrode subassembly, battery and consumer

Info

Publication number: CN115189038A
Application number: CN202210931120.8A
Authority: CN
Inventors: 邹本辉; 赵烨; 沙大喜; 汤田华; 王挺
Original assignee: Suzhou Rongrui Electronic Technology Co ltd
Current assignee: Suzhou Rongrui Electronic Technology Co ltd
Priority date: 2022-08-04
Filing date: 2022-08-04
Publication date: 2022-10-14

Abstract

The application provides an electrode piece unit, electrode subassembly, battery and consumer relates to the battery field. The electrode sheet unit includes: the electrode comprises at least one first pole piece and at least two second pole pieces, wherein the polarities of the second pole pieces are opposite to that of the first pole pieces, the second pole pieces and the first pole pieces are alternately stacked in the thickness direction of an electrode pole piece unit, a diaphragm is arranged between each second pole piece and the adjacent first pole piece, and the second pole pieces and the first pole pieces are respectively provided with active material layers which are in contact with the diaphragm; the electrode pole piece unit is provided with a first side and a second side which are opposite along the thickness direction of the electrode pole piece unit, the first side and the second side are second pole pieces, one side of the second pole piece, which is positioned on the first side and deviates from the diaphragm, is not provided with an active substance layer, and one side of the second pole piece, which is positioned on the second side and deviates from the diaphragm, is not provided with an active substance layer. The electric vehicle can solve the technical problems that the existing electric vehicle is heavy in weight, short in endurance mileage and easy to bulge in the actual operation process, and the battery is burnt out due to short circuit.

Description

Electrode pole piece unit, electrode subassembly, battery and consumer

Technical Field

The application relates to the field of batteries, in particular to an electrode plate unit, an electrode assembly, a battery and electric equipment.

Background

With the development of economy and the advancement of society, the development of technology has become necessarily and socially recognized. Electric vehicles are rapidly developed and gradually replace traditional fuel vehicles. The electric vehicle drives the vehicle to run by taking the power battery as power, and is favored by more and more people because the electric vehicle has less pollution to the environment.

At present, the electric vehicle has the problems that the whole vehicle is heavy in weight, the endurance mileage is short, and a battery is easy to bulge in the actual operation process to cause short circuit and burn out.

Disclosure of Invention

An object of the embodiment of the application is to provide an electrode piece unit, electrode subassembly, battery and consumer, it can improve the whole car weight of current electric vehicle heavy, the continuation of the journey mileage is shorter, and the easy bulging of battery leads to its short circuit to burn out's technical problem in the actual operation process.

In a first aspect, an embodiment of the present application provides an electrode sheet unit, which includes: the electrode comprises at least one first pole piece and at least two second pole pieces, wherein the polarity of the second pole pieces is opposite to that of the first pole pieces, the second pole pieces and the first pole pieces are alternately stacked in the thickness direction of an electrode pole piece unit, a diaphragm is arranged between each second pole piece and the adjacent first pole piece, and the second pole pieces and the first pole pieces are respectively provided with an active material layer in contact with the diaphragm; the electrode pole piece unit is provided with a first side and a second side which are opposite along the thickness direction of the electrode pole piece unit, the first side and the second side are second pole pieces, one side, deviating from the diaphragm, of the second pole piece on the first side is not provided with an active material layer, and one side, deviating from the diaphragm, of the second pole piece on the second side is not provided with an active material layer.

The application provides an electrode plate unit, utilize the improvement of its structure, make it compare in the motor plate unit that current positive plate/diaphragm/negative pole piece constitute, under the prerequisite that the capacity is the same, can effectively reduce the use amount of the mass flow body of first pole piece, thereby when being applied to in the battery and relevant consumer (for example new forms of energy electric automobile), on the one hand can effectively reduce the volume of electrode subassembly under the prerequisite that the capacity is the same, so that the consumer that uses the battery that contains above-mentioned electrode plate realizes lightweight setting, and effectively increase the capacity under the prerequisite that the volume is the same, thereby improve new forms of energy electric automobile's continuation of the journey mileage, on the other hand in the battery use, utilize effectively to reduce the mass flow body of first pole piece under the prerequisite that the capacity is the same, in order to alleviate the battery inflation that leads to the fact because of the heat conduction of mass flow body, thereby improve the security performance of battery, and effectively reduce manufacturing cost.

In one possible embodiment, the first pole piece is a positive pole piece and the second pole piece is a negative pole piece.

In one possible embodiment, the first pole piece is a negative pole piece, and the second pole piece is a positive pole piece.

In the above-mentioned two kinds of realization processes, technical staff in the field can select the mode of setting of electrode sheet unit according to the demand of reality, and the mode of setting is more nimble, and above-mentioned two kinds of modes of setting all can improve current new forms of energy electric automobile whole car weight heavily, the mileage of continuing a journey is shorter, and the battery easily bloated problem that leads to its short circuit to burn out among the actual operation process, and technical staff in the field can select according to the demand of reality.

In a possible embodiment, the number of first pole pieces is one and the number of second pole pieces is two.

In the implementation process, the electrode pole piece unit is simple in structure and convenient to set.

In one possible embodiment, the positive electrode sheet includes a positive electrode current collector having a thickness of 10 to 20 μm and a positive electrode active material layer formed on at least one side of the positive electrode current collector.

In the above-mentioned realization in-process, the thickness of above-mentioned anodal mass flow body is reasonable, has the support performance of preferred, if thickness is too thin, will lead to among the positive plate forming process yielding and intensity easy fracture inadequately, if thickness is too thick, the cost of manufacture is high and easily lead to the battery inflation, influences the security performance of battery.

In one possible embodiment, the negative electrode sheet includes a negative electrode current collector having a thickness of 4.5 to 20 μm and a negative electrode active material layer formed on at least one side of the negative electrode current collector.

In the implementation process, the thickness of the negative current collector is reasonable, the negative current collector has better supporting performance, if the thickness is too thin, the negative plate is easy to deform and the strength is not easy to break, and if the thickness is too thick, the manufacturing cost is high, the battery expansion is easy to cause, and the safety performance of the battery is influenced.

In one possible embodiment, the thickness of the electrode sheet unit is 50-300um.

In the implementation process, the thickness is reasonable, and the preparation requirement of the battery is met.

In a second aspect, embodiments of the present application provide an electrode assembly, where the electrode assembly is an electrode sheet unit provided in the above embodiments in a winding arrangement, or the electrode assembly is an electrode sheet unit provided in a plurality of the above embodiments in a stacking arrangement.

In the implementation process, the electrode pole piece unit can be wound or stacked according to actual requirements, and when the electrode pole piece unit is applied to a battery for supplying energy to electric equipment, the problems that the whole vehicle of the existing new energy electric vehicle is heavy in weight, the endurance mileage is short, and the battery is easy to bulge in the actual operation process to cause short circuit and burn are solved.

In a third aspect, embodiments of the present application provide a battery, which includes the electrode assembly provided in the above embodiments.

In a fourth aspect, an electric device in an embodiment of the present application includes the battery provided in the foregoing embodiment, and the battery is used for supplying power.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

Fig. 1 is a schematic structural diagram of an electrode sheet unit according to some embodiments of the present disclosure;

fig. 2 is a schematic structural diagram of an electrode sheet unit according to some embodiments of the present disclosure;

fig. 3 is a schematic structural diagram of an electrode sheet unit provided in embodiment 1 of the present application;

fig. 4 is a schematic structural diagram of an electrode sheet unit provided in embodiment 2 of the present application.

An icon: 10-electrode sheet unit; 100-a first pole piece; 110-a second pole piece; 120-positive plate; 121-positive current collector; 123-positive electrode active material layer; 130-negative plate; 131-a negative current collector; 133-negative electrode active material layer; 140-a membrane.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solutions of the present application more clearly, and therefore are only used as examples, and the protection scope of the present application is not limited thereby.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof, in the description and claims of this application and the description of the above figures are intended to cover non-exclusive inclusions.

In the description of the embodiments of the present application, the technical terms "first", "second", and the like are used only for distinguishing different objects, and are not to be construed as indicating or implying relative importance or to implicitly indicate the number, specific order, or primary-secondary relationship of the technical features indicated. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), and similarly, "plural sets" refers to two or more (including two), and "plural pieces" refers to two or more (including two).

In the description of the embodiments of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the directions or positional relationships indicated in the drawings, and are only for convenience of description of the embodiments of the present application and for simplicity of description, but do not indicate or imply that the referred device or element must have a specific direction, be constructed and operated in a specific direction, and thus, should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "fixed," and the like are used in a broad sense, and for example, may be fixedly connected, detachably connected, or integrated; mechanical connection or electrical connection is also possible; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

At present, the application of the power battery is more and more extensive from the development of market situation. The power battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles, electric automobiles and the like, and a plurality of fields such as military equipment and aerospace. With the continuous expansion of the application field of the power battery, the market demand is also continuously expanded.

However, in the actual use process, taking an electric vehicle as an example, the problems that the whole vehicle is heavy in weight, the endurance mileage is short, and the battery is easy to swell in the actual operation process to cause short circuit and burnout exist.

The inventors have found that one of the reasons that the battery is easily swelled to cause short circuit burnout during actual operation is that the current collector of the electrode assembly is a heat conductive metal, which is capable of rapidly conducting heat to expand the active material layer during use, thereby causing the battery to expand to cause short circuit burnout. In order to solve the endurance mileage, the capacity per unit volume is usually increased, but the weight of the whole vehicle is inevitably increased. Therefore, it is a difficult point to increase the capacity per unit volume of the battery and reduce the weight of the battery with the same capacity, and to simultaneously alleviate the swelling of the battery.

In order to solve the above problems, the inventors attempted to modify the structure of an electrode tab unit for winding or laminating an electrode assembly to obtain an electrode assembly in order to improve the above technical problems. The improved electrode sheet unit comprises: the electrode comprises at least one first pole piece and at least two second pole pieces, wherein the polarity of the second pole pieces is opposite to that of the first pole pieces, the second pole pieces and the first pole pieces are alternately stacked in the thickness direction of an electrode pole piece unit, a diaphragm is arranged between each second pole piece and the adjacent first pole piece, and the second pole pieces and the first pole pieces are respectively provided with an active material layer in contact with the diaphragm; the electrode pole piece unit is provided with a first side and a second side which are opposite along the thickness direction of the electrode pole piece unit, the first side and the second side are second pole pieces, one side of the second pole piece, which is positioned on the first side and deviates from the diaphragm, is not provided with an active substance layer, and one side of the second pole piece, which is positioned on the second side and deviates from the diaphragm, is not provided with an active substance layer.

By utilizing the improvement of the structure, compared with the existing motor pole piece unit formed by the positive pole piece, the diaphragm and the negative pole piece, on the premise of the same capacity, the usage amount of the current collector of the first pole piece can be effectively reduced, so that when the current collector is applied to a battery and related electric equipment (such as a new energy electric automobile), on one hand, the volume of an electrode assembly can be effectively reduced on the premise of the same capacity, so that the light weight setting of the electric equipment using the battery containing the electrode pole piece is realized, and the capacity is effectively increased on the premise of the same volume, so that the endurance mileage of the new energy electric automobile is improved, on the other hand, in the using process of the battery, the current collector of the first pole piece is effectively reduced on the premise of the same capacity, so that the battery expansion caused by the heat conduction of the current collector is relieved, the safety performance of the battery is improved, and the production cost is effectively reduced.

The battery disclosed in the embodiment of the present application may be used in, but is not limited to, an electric device for a vehicle, a ship, an aircraft, or the like. The power supply system with the battery and the like disclosed by the application can be used for forming the electric device, so that the expansion and deterioration of the battery can be relieved and automatically adjusted, the stability of the battery is improved, and the lightweight arrangement and the better endurance mileage of the electric device can be realized.

The embodiment of the application provides an electric device using a battery as a power supply, wherein the electric device can be but is not limited to a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric automobile, a ship, a spacecraft and the like. The electric toy may include a stationary or mobile electric toy, such as a game machine, an electric car toy, an electric ship toy, an electric airplane toy, and the like, and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, and the like. In the following embodiments, the electric device is taken as an electric vehicle, and specifically, a new energy automobile is taken as an example to describe the effect.

The embodiment of the application provides a new energy automobile, and it includes the battery, and the battery can be used for the power supply to new energy automobile to the work power consumption demand when satisfying new energy automobile's start-up, navigation and going.

The battery comprises a box body and a plurality of battery monomers accommodated in the box body to form a battery module, wherein the battery monomers are the minimum units forming the battery. The battery cell includes an end cap, a case, an electrode assembly and other functional components, and the specific arrangement is referred to in the related art and is not limited herein.

The electrode assembly is a component in which electrochemical reactions occur in the battery cell. The electrode assembly is obtained by winding the electrode pole piece unit, or the electrode assembly is obtained by laminating a plurality of electrode pole piece units.

That is, the electrode assembly is an electrode tab unit arranged in a winding manner, or the electrode assembly is a plurality of electrode tab units arranged in a lamination manner.

Referring to fig. 1 and 2, according to some embodiments of the present application, optionally, the electrode sheet unit 10 includes: at least one first pole piece 100 and at least two second pole pieces 110.

The polarities of the second pole piece 110 and the first pole piece 100 are opposite, the second pole piece 110 and the first pole piece 100 are alternately stacked in the thickness direction of the electrode pole piece unit 10, a diaphragm 140 is arranged between the second pole piece 110 and the adjacent first pole piece 100, and the second pole piece 110 and the first pole piece 100 are respectively provided with an active material layer contacting with the diaphragm 140; the electrode sheet unit 10 has a first side and a second side opposite to each other along the thickness direction thereof, the first side and the second side are both the second sheet 110, the side of the second sheet 110 on the first side facing away from the diaphragm 140 is not provided with an active material layer, and the side of the second sheet 110 on the second side facing away from the diaphragm 140 is not provided with an active material layer.

The side of the second pole piece 110 facing away from the diaphragm 140 on the first side is not provided with an active material layer, which means that: the current collector of the second pole piece 110 on the first side is not provided with an active material layer on the side away from the separator 140, and directly exposes the current collector.

The side of the second pole piece 110 facing away from the diaphragm 140 and not provided with an active material layer means that: the current collector of the second pole piece 110 on the second side is not provided with an active material layer on the side away from the separator 140, and directly exposes the current collector.

Compared with the existing motor pole piece unit formed by the positive pole piece 120, the diaphragm 140 and the negative pole piece 130, the electrode pole piece unit 10 provided by the application can effectively reduce the usage amount of the current collector of the first pole piece 100 on the premise of the same capacity, so that when the electrode pole piece unit is applied to a battery and related electric equipment (such as a new energy electric automobile), on one hand, the volume of an electrode assembly can be effectively reduced on the premise of the same capacity, so that the light weight setting of the electric equipment using the battery containing the electrode pole piece is realized, and on the premise of the same volume, the capacity is effectively increased, so that the endurance mileage of the new energy electric automobile is improved, and on the other hand, in the use process of the battery, the current collector of the first pole piece 100 is effectively reduced on the premise of the same capacity, so that the battery expansion caused by the heat conduction of the current collector is relieved, so that the safety performance of the battery is improved, and the production cost is effectively reduced.

Here, the number of the first pole pieces 100 is at least one, for example, one, two, or three, and the like, and the number of the second pole pieces 110 is at least two, for example, two, three, or four, and the like, it can be understood that, since the second pole pieces 110 and the first pole pieces 100 are alternately stacked in the thickness direction of the electrode pole piece unit 10, and the first side and the second side are both the second pole pieces 110, that is, the number of the second pole pieces 110 is greater than the number of the first pole pieces 100.

As shown in fig. 1, the number of the first pole pieces 100 is two, and the number of the second pole pieces 110 is three, and at this time, active material layers contacting with the separator 140 are formed on both surfaces of the second pole piece 110 located between the two first pole pieces 100.

As shown in fig. 2, in the present embodiment, the number of the first pole pieces 100 is one, and the number of the second pole pieces 110 is two, and at this time, the electrode pole piece unit 10 is in a sandwich structure.

As shown in fig. 2 and 3, according to some embodiments of the present application, optionally, the first pole piece 100 is a positive pole piece 120, and the second pole piece 110 is a negative pole piece 130.

As shown in fig. 2 and 4, according to some embodiments of the present application, optionally, the first pole piece 100 is a negative pole piece 130, and the second pole piece 110 is a positive pole piece 120.

In any of the above arrangements, the positive electrode sheet 120 includes a positive electrode collector 121 and a positive electrode active material layer 123 formed on at least one surface of the positive electrode collector 121, and the thickness of the positive electrode collector 121 is 10 to 20 μm.

Above-mentioned anodal mass flow body 121's thickness is reasonable, has the support performance of preferred, if the thickness is too thin, will lead to yielding in the positive plate 120 forming process and intensity easy fracture inadequately, if the thickness is too thick, the cost of manufacture is high and easily lead to the battery inflation, influences the security performance of battery.

It is understood that when the positive electrode sheet 120 is laminated with the separator 140 on both sides in the thickness direction, the positive electrode active material layer 123 on both sides in the thickness direction of the positive electrode collector 121, and when the positive electrode sheet 120 is the second sheet 110 on the first side or the second side, the positive electrode sheet 120 is provided with the positive electrode active material layer 123 only on the side facing the separator 140, and the positive electrode active material layer 123 is not provided on the other side.

Illustratively, the thickness of the positive electrode collector 121 is any one of 10 μm, 11 μm, 13 μm, 15 μm, 17 μm, 18 μm, 20 μm, or between any two values.

The positive electrode current collector 121 is selected from an aluminum foil, for example, one of a porous aluminum foil and an etched aluminum foil.

The positive electrode active material includes, but is not limited to, at least one of lithium nickel cobalt oxide, lithium iron phosphate, lithium manganate, spinel lithium nickel manganese oxide, ternary nickel cobalt manganese oxide, and the like.

The negative electrode sheet 130 includes a negative electrode collector 131 and a negative electrode active material layer 133 formed on at least one surface of the negative electrode collector 131, and the thickness of the negative electrode collector 131 is 4.5 to 20 μm.

The negative current collector 131 is reasonable in thickness and has better supporting performance, if the thickness is too thin, the negative plate 130 is easy to deform in the forming process and the strength is not easy to break, and if the thickness is too thick, the manufacturing cost is high, the battery expansion is easy to cause, and the safety performance of the battery is influenced.

It is understood that when the negative electrode sheet 130 is laminated with the separator 140 on both sides in the thickness direction, the negative electrode active material layer 133 on both sides in the thickness direction of the positive electrode collector 121, and when the negative electrode sheet 130 is the second sheet 110 on the first side or the second side, the negative electrode sheet 130 is provided with the negative electrode active material layer 133 only on the side facing the separator 140 and the negative electrode active material layer 133 is not provided on the other side.

Illustratively, the thickness of the negative electrode current collector 131 is any one of or between 4.5 μm, 5 μm, 6.5 μm, 8 μm, 10 μm, 13 μm, 15 μm, 17 μm, 18 μm, 20 μm.

The material of the negative electrode current collector 131 includes, but is not limited to, elemental copper, copper alloy, or a composite material of copper and a noble metal.

The anode active material is at least one of a carbon-based material, which may be at least one of graphite, mesocarbon microbeads, hard carbon, soft carbon, etc., a silicon-based material, which may be at least one of silicon carbon and silicon oxide, and a metal oxide, which may be at least one of iron oxide and tin oxide.

The separator 140 includes a PP or PE composite film.

The thickness of the electrode sheet unit 10 is 50-300um.

The thickness is reasonable, and the preparation requirement of the battery is met.

Illustratively, the thickness of the electrode sheet unit 10 is any one value or between any two values of 50 μm, 70 μm, 100 μm, 130 μm, 150 μm, 180 μm, 200 μm, 230 μm, 250 μm, 280 μm, 300 μm.

The electrode plate unit, the electrode assembly, the battery and the electric device of the present application are further described in detail with reference to the following examples.

Examples and comparative examples

[ cathode paste ]:

adding lithium iron phosphate, acetylene black and polyvinylidene fluoride into a stirring tank according to the mass ratio of 97.2.

[ anode slurry ]: the conductive carbon black is composed of 97wt% of graphite, 1wt% of conductive carbon black and 2wt% of styrene butadiene rubber.

[ first positive electrode sheet ] the positive electrode slurry was coated on both side surfaces of a positive electrode current collector (aluminum foil) with a coater, dried at 120 ℃, and then rolled to obtain a double-coated first positive electrode sheet.

[ second positive plate ] it only differs from the first positive plate in that: the positive electrode slurry was coated on a single side of a positive electrode current collector (aluminum foil) with a coater.

Coating the positive slurry on two side surfaces of a negative current collector (copper foil) by using a coating machine, drying, and rolling to obtain the first negative plate coated on two sides.

The difference between the second negative plate and the first negative plate is only that: the positive electrode slurry was coated on a single side of a positive electrode current collector (aluminum foil) with a coater.

[ DIAPHRAGM ] a polypropylene film having a thickness of 45 um.

[ ASSEMBLED ELECTRODE PIECE UNIT ]

The structure of the electrode sheet unit of example 1 is shown in fig. 3, and the electrode sheet unit is obtained by sequentially stacking a second negative electrode sheet, a separator, a first positive electrode sheet, a separator, and a second negative electrode sheet.

As shown in fig. 4, the electrode sheet unit of example 2 is obtained by sequentially stacking a second positive sheet, a separator, a first negative sheet, a separator, and a second positive sheet.

The electrode plate unit of the comparative example 1 is obtained by sequentially overlapping a diaphragm, a first negative plate, a diaphragm and a first positive plate.

The capacities of example 1 and comparative example 1 were the same.

[ ELECTROLYTE ] LIPF (lithium ion plasma) ₆ Dissolving ethylene carbonate, ethyl methyl carbonate and diethyl carbonate in a volume ratio of 1:1:1, an electrolyte solution having a concentration of 1mol/L is prepared.

The bare cell obtained by winding the electrode plate unit is placed in a packaging shell, dried and injected with electrolyte, and then subjected to vacuum packaging, standing, formation, shaping and other processes to obtain the lithium ion battery.

The thickness parameters, capacity, weight, volume, expansion coefficient and manufacturing cost of the electrode sheet units obtained in each example and comparative example were measured, and the results are shown in table 1.

TABLE 1

As can be seen from table 1, in example 1 and comparative example 1, the weight is reduced by 2 to 4%, the volume is reduced by 3%, the expansion rate is reduced by 3 to 5%, and the manufacturing cost is reduced by 4 to 8% under the premise of the same capacity.

That is, compared with the method of comparative example 1, the electrode plate unit prepared by the method of the present application can increase the capacity of the battery in unit volume or weight, so that the endurance mileage of the battery can be increased when the battery is applied to an electric vehicle, and on the premise of the same endurance mileage, the total vehicle weight and the expansion rate of the battery can be reduced, and the safety and the stability of operation can be improved.

In conclusion, the electrode plate unit provided by the application utilizes the improvement of the structure thereof, so that the electrode plate unit is compared with the existing electrode plate unit, on one hand, the volume of an electrode assembly can be effectively reduced on the premise of the same capacity, so that the light weight setting of the electric equipment of the battery containing the electrode plate is realized, and the capacity is effectively increased on the premise of the same volume, so that the endurance mileage of the new energy electric automobile is improved, on the other hand, in the use process of the battery, the current collector of the first electrode plate is effectively reduced on the premise of the same capacity, so that the battery expansion caused by the heat conduction of the current collector is relieved, the safety performance of the battery is improved, and the production cost is effectively reduced.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An electrode sheet unit, comprising:

at least one first pole piece;

the polarity of the second pole pieces is opposite to that of the first pole pieces, the second pole pieces and the first pole pieces are alternately stacked in the thickness direction of the electrode pole piece units, a diaphragm is arranged between each second pole piece and the adjacent first pole piece, and the second pole pieces and the first pole pieces are respectively provided with an active material layer in contact with the diaphragm;

the electrode pole piece unit is provided with a first side and a second side which are opposite along the thickness direction of the electrode pole piece unit, the first side and the second side are both second pole pieces, the second pole piece unit is positioned on the first side and deviates from one side of the diaphragm, the active substance layer is not arranged on the side of the second pole piece unit, and the active substance layer is not arranged on the side of the second pole piece unit deviating from the diaphragm.

2. The electrode tab unit of claim 1 wherein the first tab is a positive tab and the second tab is a negative tab.

3. The electrode tab unit of claim 1 wherein the first tab is a negative tab and the second tab is a positive tab.

4. The electrode sheet unit according to claim 2 or 3, wherein the number of the first sheet is one and the number of the second sheet is two.

5. The electrode tab unit according to claim 2 or 3, wherein the positive electrode tab comprises a positive electrode current collector and a positive electrode active material layer formed on at least one surface of the positive electrode current collector, and the thickness of the positive electrode current collector is 10-20 μm.

6. The electrode tab unit according to claim 2 or 3, wherein the negative electrode tab comprises a negative electrode current collector and a negative electrode active material layer formed on at least one side of the negative electrode current collector, and the thickness of the negative electrode current collector is 4.5 to 20 μm.

7. The electrode sheet unit of claim 1, wherein the thickness of the electrode sheet unit is 50-300um.

8. An electrode assembly, wherein the electrode assembly is an electrode sheet unit according to any one of claims 1 to 7 in a wound arrangement, or a plurality of electrode sheet units according to any one of claims 1 to 7 in a stacked arrangement.

9. A battery comprising the electrode assembly of claim 8.

10. An electrical consumer comprising the battery of claim 9, wherein the battery is configured to provide power.