CN210897515U - Battery cell structure and lithium battery - Google Patents

Abstract

The present application belongs to the technical field of lithium ion batteries, and in particular relates to a cell structure and a lithium battery. The battery core structure includes: a single-layer positive electrode sheet, the single-layer positive electrode sheet includes a three-dimensional porous metal current collector, the positive electrode slurry can be embedded in the pores of the metal current collector, and the thickness of the single-layer positive electrode sheet is 2- 100 mm; a single-layer negative electrode sheet, the material of the single-layer negative electrode sheet includes foam carbon, and the thickness of the single-layer negative electrode sheet is 1-50 mm; a ceramic separator is located between the single-layer positive electrode sheet and the single-layer negative electrode sheet between, the thickness is 0.05‑0.5 mm. This single-layer positive electrode sheet, separator, and single-layer negative electrode sheet structure can simplify the cell production process and control factors, thereby improving cell production efficiency and reducing production costs. The single-layer negative electrode sheet and the ceramic diaphragm with a thickness of millimeters are produced, which can increase the capacity of the cell, improve the safety performance of the cell, and reduce the self-discharge of the cell.

Description

Cell structure and lithium battery

technical field

The present application belongs to the technical field of lithium ion batteries, and in particular relates to a cell structure and a lithium battery including the cell structure.

Background technique

Due to its high energy density, high power density, long cycle life, no memory effect, low self-discharge rate, wide operating temperature range, safety and reliability, and environmental friendliness, lithium-ion batteries have been used in portable electronic products and electric vehicles. has been widely used.

In recent years, with the continuous growth of the portable electronics and electric vehicle market, in order to obtain longer standby time or driving range, there is an increasing market demand for lithium-ion batteries with lighter weight, smaller size, higher capacity and energy density big.

When lithium-ion cells are used in electric vehicles or energy storage, dozens or even thousands of cells are generally required to form a system. In order to ensure the performance of battery system power and service life, the matched cells are required to have high consistency. The traditional lithium-ion battery is composed of multiple layers of positive and negative electrodes that are wound or laminated. The production process is relatively complex, and there are dozens of key control points in the process, which requires extremely high production technology and production equipment.

Therefore, it is necessary to develop a new lithium-ion cell structure to optimize cell performance, improve cell production efficiency, and reduce production costs.

Utility model content

The present application provides a cell structure and a lithium battery including the cell structure, which can optimize cell performance, improve cell production efficiency, and reduce production costs.

One aspect of the present application provides a battery core structure, comprising: a single-layer positive electrode sheet, the single-layer positive electrode sheet includes a three-dimensional porous metal current collector, the positive electrode slurry can be embedded in the pores of the metal current collector, and the single-layer positive electrode sheet can be embedded in the pores of the metal current collector. The thickness of the positive electrode sheet is 2-100 mm; the single-layer negative electrode sheet, the material of the single-layer negative electrode sheet includes foam carbon, and the thickness of the single-layer negative electrode sheet is 1-50 mm; the ceramic separator is located in the single-layer positive electrode sheet and the single-layer negative electrode sheet, the thickness is 0.05-0.5 mm.

In some embodiments of the present application, the three-dimensional porous metal is aluminum foam with a porosity of 50%-90%.

In some embodiments of the present application, the porosity of the foamed carbon is 50%-90%.

In some embodiments of the present application, the pore diameter of the foamed carbon is 0.01-10 microns.

In some embodiments of the present application, the porosity of the single-layer positive electrode sheet is 10%-40%.

In some embodiments of the present application, the connection portion between the carbon foam and the tab further includes a copper plating layer.

Another aspect of the present application provides a lithium battery, including the above-mentioned cell structure.

A cell structure and a lithium battery including the cell structure provided by the present application use a single-layer positive electrode sheet, a separator, and a single-layer negative electrode sheet structure, which can simplify the cell production process and control elements, thereby improving the cell production efficiency. , reduce production costs, the use of single-layer positive plates made of three-dimensional porous metal, single-layer negative plates made of foam carbon and ceramic diaphragms with a thickness of millimeters can increase the capacity of the cell, improve the safety performance of the cell, and reduce the number of cells. self-discharge.

Description of drawings

The following drawings describe in detail exemplary embodiments disclosed in this application. Where like reference numbers refer to similar structures throughout the several views of the drawings. Those of ordinary skill in the art will understand that these embodiments are non-limiting, exemplary embodiments, the accompanying drawings are for illustration and description purposes only, and are not intended to limit the scope of the present disclosure, and other embodiments are possible The same accomplishes the utility model intent in this application. It should be understood that the figures are not drawn to scale. in:

FIG. 1 is a schematic structural diagram of a cell structure according to an embodiment of the present application.

Detailed ways

The following description provides specific application scenarios and requirements of the present application, and is intended to enable those skilled in the art to make and use the contents of the present application. Various partial modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and without departing from the spirit and scope of the present disclosure. application. Thus, the present disclosure is not to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the claims.

The technical solutions of the present utility model will be described in detail below with reference to the embodiments.

FIG. 1 is a schematic structural diagram of a cell structure according to an embodiment of the present application.

The embodiment of the present application provides a cell structure, as shown in FIG. 1 , the cell structure includes: a single-layer positive electrode sheet 110 , the single-layer positive electrode sheet 110 includes a three-dimensional porous metal current collector, and the positive electrode slurry can be embedded in the In the pores of the metal current collector, the thickness of the single-layer positive electrode sheet 110 is 2-100 mm; the single-layer negative electrode sheet 130, the material of the single-layer negative electrode sheet 130 includes foam carbon, and the single-layer negative electrode sheet 130 The thickness is 1-50 mm; the ceramic separator 120 is located between the single-layer positive electrode sheet 110 and the single-layer negative electrode sheet 130, and the thickness is 0.05-0.5 mm.

The traditional battery cell is composed of multiple layers of micron-thick positive electrode sheets and negative electrode sheets that are wound or laminated. The production process is relatively complicated, and there are dozens of key control points in the process. Extremely demanding. However, the cell structure described in the embodiment of the present application only includes a layer of millimeter-scale positive electrode sheets and a layer of millimeter-scale negative electrode sheets, and the positive electrode sheet and the negative electrode sheet are separated by a layer of millimeter-scale ceramic separators. The single-layer cell structure is not only simple in process, but also improves cell safety and cell capacity.

Referring to FIG. 1 , the single-layer positive electrode sheet 110 uses a three-dimensional porous metal current collector, the positive electrode slurry is filled in the pores of the metal current collector, and the positive electrode can adsorb electrolyte through capillary action. Since the positive active material is filled inside the current collector, compared with the conventional positive electrode sheet coated with the positive active material on the surface of the current collector, it can reduce the distance of the electron channel, avoid the polarization during the charging and discharging process caused by the ultra-thick electrode, and ensure the power characteristics of the cell. . At the same time, due to its thermal conductivity, the metal can take away the heat generated during the charging and discharging process of the positive electrode active material, thereby reducing the internal temperature rise of the battery cell.

In some embodiments of the present application, the three-dimensional porous metal is aluminum foam with a porosity of 50%-90%. Porosity refers to the proportion of the pores inside the material to the total volume in the apparent volume of the granular material. In some embodiments of the present application, under the condition of ensuring sufficient physical strength of the metal current collector, the porosity should be as high as possible to accommodate more positive active materials and improve battery capacity.

In some embodiments of the present application, the thickness of the aluminum foam is 2-100 mm. The thickness of the foamed aluminum can be designed according to the required thickness of the cell.

In some embodiments of the present application, the viscosity of the cathode slurry is 5000-30000 cp. The viscosity of the positive electrode slurry cannot be too high, otherwise it is difficult to fill into the pores of the metal current collector; the viscosity of the positive electrode slurry cannot be too low, otherwise it is easy to flow out from the pores of the metal current collector. The positive electrode slurry is prepared by a conventional method, which will not be repeated here.

In some embodiments of the present application, the positive electrode slurry includes a positive electrode active material, such as, for example, lithium iron phosphate or lithium nickel cobalt manganate.

In some embodiments of the present application, the positive electrode slurry may further include auxiliary materials such as a solvent, a binder, and a conductive agent.

In some embodiments of the present application, the porosity of the single-layer positive electrode sheet 110 is 10%-40%. The single-layer positive electrode sheet 110 is obtained by filling the positive electrode slurry with the metal current collector. The porosity of the single-layer positive electrode sheet 110 cannot be too low, otherwise the ability of the single-layer positive electrode sheet 110 to absorb electrolyte will be reduced. , the porosity of the single-layer positive electrode sheet 110 cannot be too high, otherwise the proportion of the positive electrode active material in the single-layer positive electrode sheet 110 will be reduced.

In some embodiments of the present application, the surface of the single-layer positive electrode sheet 110 can also be coated with a ceramic coating or an aramid coating using a gravure coating technology, and the coating thickness is 2-3um, so as to improve the high temperature resistance of the cell and security.

Continuing to refer to FIG. 1 , the single-layer negative electrode sheet 130 described in the embodiment of the present application uses foamed carbon that has undergone inert treatment. Compared with the negative electrode slurry coated on the surface of the conventional negative electrode sheet, there is no need to prepare negative electrode slurry, which simplifies the production process. On the one hand, compared with the intercalation of lithium ions between the multi-layered negative plates in the conventional negative electrode, the micropores on the foamed carbon can directly absorb lithium ions, thereby improving the first charge and discharge efficiency of the battery cell.

Inert treatment on the surface of the active part of the foamed carbon can prevent lithium dendrites from precipitating on the surface of the foamed carbon during the charging process of the battery cell.

Foamed carbon has the characteristics of low density, high strength, easy processing, and good physical and chemical properties such as electrical conductivity and thermal conductivity, and is very suitable for use as electrode materials.

In some embodiments of the present application, the porosity of the foamed carbon is 50%-90%. In some embodiments of the present application, under the condition that the physical strength of the carbon foam is sufficient, the porosity should be as high as possible to accommodate more lithium ions and improve the battery capacity.

In some embodiments of the present application, the density of the foamed carbon is 0.18-0.9 g/cm ³ . In the case of the same size, the lower the density of the carbon foam, the lighter the weight of the cell.

In some embodiments of the present application, the pore diameter of the foamed carbon is 0.01-10 microns, and the average pore diameter is 0.5-2 microns. The micropore diameter is related to the reversibility of lithium metal in the charging and discharging process. Too small micropore diameter is not conducive to ensuring the reversibility of the charging and discharging process of the deposited lithium metal, thereby reducing the cycle life.

In some embodiments of the present application, the thickness of the foamed carbon is 1-50 mm. The thickness of the foamed carbon can be designed according to the required thickness of the cell.

In some embodiments of the present application, the position of the negative electrode ear reserved on the carbon foam is copper-plated, so that the negative electrode ear can be welded. Therefore, the connection part between the carbon foam and the electrode ear also includes plating. copper layer.

In some embodiments of the present application, the thickness of the ceramic membrane 120 is 0.05-0.5 mm. The thickness of the ceramic diaphragm 120 can be designed according to the required thickness of the cell. The ceramic diaphragm 120 has high mechanical strength, which can effectively prevent short circuit inside the pole piece and reduce the self-discharge of the cell.

In some embodiments of the present application, the ceramic diaphragm 120 includes a microporous structure, the pore size of the micropores is between 10-100 nm, and the surface of the ceramic diaphragm 120 is further treated with glue, and the thickness of the glue layer is 2-3um, the adhesive layer is mainly water-based PVDF, and the porosity of the ceramic diaphragm 120 is between 40%-60%.

In some embodiments of the present application, the ceramic diaphragm 120 may be designed with a self-closing cell pattern, which is used to avoid short circuit of the cells when the temperature is high.

The battery cell structure provided by the present application adopts the structure of a single-layer positive electrode sheet, a separator, and a single-layer negative electrode sheet, which can simplify the battery cell production process and control elements, thereby improving the battery cell production efficiency and reducing the production cost, using three-dimensional porous metal The single-layer positive electrode sheet produced, the single-layer negative electrode sheet made of foam carbon and the ceramic diaphragm with a thickness of millimeters can increase the cell capacity, improve the safety performance of the cell, and reduce the self-discharge of the cell.

The present application further provides a lithium battery, including the cell structure described in the embodiments of the present application.

The embodiments of the present application also provide a method for fabricating a cell structure, including: fabricating a single-layer positive electrode sheet, wherein the single-layer positive electrode sheet includes a three-dimensional porous metal current collector, and the positive electrode slurry can be embedded in the pores of the metal current collector The thickness of the positive electrode sheet is 2-100 mm; the positive electrode slurry is embedded in the pores of the metal current collector; the surface of the foamed carbon active part is inertly treated to form a single-layer negative electrode sheet, and the single-layer negative electrode sheet has The thickness is 1-50 mm; the single-layer positive electrode sheet, the single-layer negative electrode sheet and the ceramic separator are assembled into a cell, wherein the separator is located between the single-layer positive electrode sheet and the single-layer negative electrode sheet, The thickness is 0.05-0.5 mm.

The single-layer positive electrode sheet uses a three-dimensional porous metal current collector, the positive electrode slurry is filled in the pores of the metal current collector, and the positive electrode can absorb the electrolyte through capillary action. Since the positive active material is filled inside the current collector, compared with the conventional positive electrode sheet coated with the positive active material on the surface of the current collector, it can reduce the distance of the electron channel, avoid the polarization during the charging and discharging process caused by the ultra-thick electrode, and ensure the power characteristics of the cell. . At the same time, due to its thermal conductivity, the metal can take away the heat generated during the charging and discharging process of the positive electrode active material, thereby reducing the internal temperature rise of the battery cell.

In some embodiments of the present application, the three-dimensional porous metal is aluminum foam with a porosity of 50%-90%. Porosity refers to the proportion of the pores inside the material to the total volume in the apparent volume of the granular material. In some embodiments of the present application, under the condition of ensuring sufficient physical strength of the metal current collector, the porosity should be as high as possible to accommodate more positive active materials and improve battery capacity.

In some embodiments of the present application, the thickness of the aluminum foam is 2-100 mm. The thickness of the foamed aluminum can be designed according to the required thickness of the cell.

In some embodiments of the present application, after selecting a suitable metal current collector material, a die can also be used to punch it to a desired size.

In some embodiments of the present application, the viscosity of the cathode slurry is 5000-30000 cp. The viscosity of the positive electrode slurry cannot be too high, otherwise it is difficult to fill into the pores of the metal current collector; the viscosity of the positive electrode slurry cannot be too low, otherwise it is easy to flow out from the pores of the metal current collector. The positive electrode slurry is prepared by a conventional method, which will not be repeated here.

In some embodiments of the present application, the positive electrode slurry includes a positive electrode active material, such as, for example, lithium iron phosphate or lithium nickel cobalt manganate.

In some embodiments of the present application, the positive electrode slurry may further include auxiliary materials such as a solvent, a binder, and a conductive agent.

In some embodiments of the present application, the method for embedding the positive electrode slurry into the pores of the metal current collector is a dipping process. Specifically, the metal current collector is immersed in the positive electrode slurry, and the positive electrode slurry is embedded in the pores of the metal current collector and taken out. Compared with the process of coating the positive electrode slurry on the surface of the current collector in the conventional positive electrode sheet, the soaking and hanging slurry process is simpler and easier to implement.

In some embodiments of the present application, the time for dipping the metal current collector into the positive electrode slurry is 5-30 minutes.

In some embodiments of the present application, in order to ensure that the inside of the metal current collector is filled with the positive electrode slurry, the metal current collector may be repeatedly dipped into the positive electrode slurry for 3-5 times.

It should be noted that during the soaking and hanging process, it is necessary to ensure that the structure of the current collector is not deformed, so as to prevent the deformation of the current collector from causing the size of the electrode plate to be inconsistent with the design size after the paste hanging.

In some embodiments of the present application, the positive electrode current collector after being filled with the positive electrode slurry may also be subjected to cold/hot pressing shaping, so as to achieve the target thickness and satisfy the designed porosity.

In some embodiments of the present application, the porosity of the single-layer positive electrode sheet is 10%-40%. The single-layer positive electrode sheet is obtained by filling the positive electrode slurry with the metal current collector. The porosity of the single-layer positive electrode sheet cannot be too low, otherwise the ability of the single-layer positive electrode sheet to absorb electrolyte will be reduced. The porosity of the single-layer positive electrode sheet also cannot be too high, otherwise the proportion of the positive electrode active material in the single-layer positive electrode sheet will be reduced.

In some embodiments of the present application, the surface of the single-layer positive electrode sheet can also be coated with a ceramic coating or an aramid coating using gravure coating technology, and the coating thickness is 2-3um, which improves the high temperature resistance of the cell and safety.

In some embodiments of the present application, the porosity of the foamed carbon is 50%-90%. In some embodiments of the present application, under the condition that the physical strength of the carbon foam is sufficient, the porosity should be as high as possible to accommodate more lithium ions and improve the battery capacity.

In some embodiments of the present application, the density of the foamed carbon is 0.18-0.9 g/cm3. In the case of the same size, the lower the density of the carbon foam, the lighter the weight of the cell.

In some embodiments of the present application, the pore diameter of the foamed carbon is 0.01-10 microns, and the average pore diameter is 0.5-2 microns. The micropore diameter is related to the reversibility of lithium metal in the charging and discharging process. Too small micropore diameter is not conducive to ensuring the reversibility of the charging and discharging process of the deposited lithium metal, thereby reducing the cycle life.

In some embodiments of the present application, the thickness of the foamed carbon is 1-50 mm. The thickness of the foamed carbon can be designed according to the required thickness of the cell.

In some embodiments of the present application, the inert treatment includes surface coating. Specifically, gravure coating technology is mainly used to coat ceramic coating or aramid coating, and the coating thickness is 2-3um. Inert treatment on the surface of the active part of the foamed carbon can prevent lithium dendrites from precipitating on the surface of the foamed carbon during the charging process of the battery cell.

In some embodiments of the present application, the manufacturing method further includes: performing copper plating on the negative electrode tabs on the carbon foam to increase weldability.

The single-layer negative electrode sheet is directly made of inert-treated foamed carbon. Compared with the conventional negative electrode sheet surface coated with negative electrode slurry, no negative electrode slurry needs to be prepared, which simplifies the production process. Foamed carbon has the characteristics of low density, high strength, easy processing, and good physical and chemical properties such as electrical conductivity and thermal conductivity, and is very suitable for use as electrode materials.

In some embodiments of the present application, the thickness of the ceramic membrane is 0.05-0.5 mm. The thickness of the ceramic separator can be designed according to the required thickness of the cell. The ceramic diaphragm has high mechanical strength, can effectively prevent the short circuit inside the pole piece, and reduce the self-discharge of the cell.

In some embodiments of the present application, the ceramic diaphragm includes a microporous structure, the diameter of the micropores is between 10-100 nm, and the surface of the ceramic diaphragm is further subjected to glue coating, and the thickness of the glue layer is 2-100 nm. 3um, the adhesive layer is mainly water-based PVDF, and the porosity of the ceramic diaphragm is between 40% and 60%.

In some embodiments of the present application, the ceramic separator can be designed with a self-closing cell pattern, which is used to avoid short circuit of the cells when the temperature is high.

A method for manufacturing a cell structure provided by the present application uses a single-layer positive electrode sheet, a separator, and a single-layer negative electrode sheet structure, which can simplify the cell production process and control elements, thereby improving cell production efficiency and reducing production costs. The single-layer positive electrode sheet made of porous metal, the single-layer negative electrode sheet made of foam carbon and the ceramic diaphragm with a thickness of millimeters can increase the cell capacity, improve the safety performance of the cell, and reduce the self-discharge of the cell.

Exemplary Embodiment 1

Foamed aluminum is selected as the positive electrode current collector, its porosity is 65%, the average pore size is 2 microns, the thickness is 34 mm, the width is 140 mm, and the height is 78 mm; the mass ratio of the current collector immersed in lithium iron phosphate is 96.5 % positive electrode slurry for 3 times, each time for 30 seconds, to ensure that the inside of the current collector is filled with positive active material, and the weight of the positive active material is 519 g; hot/cold pressing is performed on the current collector filled with positive active material After shaping, a single-layer positive electrode sheet was obtained, and the thickness of the single-layer positive electrode sheet was 30.35 mm.

A carbon foam with a porosity of 80% and a density of 0.36 g/cm ³ was selected as the single-layer negative electrode sheet. The thickness of the carbon foam was 5.5 mm, the width was 142 mm, the height was 80 mm, and the average value of the micropore diameter was 0.5 mm. Micron, the micropore volume is 50cm ³ ; the surface of the foamed carbon is inertly treated; the single-layer negative electrode tab is plated with copper to increase its weldability. Among them, the negative electrode micropore volume is 50 cm ³ , the volume of lithium metal intercalated after the cell is charged is 40 cm ³ , and the negative electrode micropore volume excess is designed to be 1.28.

The single-layer positive electrode sheet, the single-layer negative electrode sheet and the ceramic separator with a thickness of 0.15 mm are assembled into a battery cell, wherein the separator is located between the single-layer positive electrode sheet and the single-layer negative electrode sheet.

Exemplary Embodiment 2

Foamed aluminum is selected as the positive electrode current collector, with a porosity of 75%, an average pore size of 2 microns, a thickness of 32 mm, a width of 140 mm, and a height of 78 mm; the current collector is immersed in nickel-cobalt lithium manganate with a mass ratio of 32 mm. Soak in 96.5% positive electrode slurry for 4 times, each time for 25 seconds, to ensure that the inside of the current collector is filled with positive active material; perform hot/cold pressing on the current collector filled with positive active material to obtain a single-layer positive electrode sheet.

A carbon foam with a porosity of 75% and a density of 0.4 g/ ^cm3 was selected as the single-layer negative electrode sheet. The thickness of the foamed carbon was 6 mm, the width was 142 mm, the height was 80 mm, and the average value of the micropore diameter was 1 micron; inert treatment on the surface of the foamed carbon; copper plating on the single-layer negative electrode tab to increase its weldability.

The single-layer positive electrode sheet, the single-layer negative electrode sheet and the ceramic separator with a thickness of 0.2 mm are assembled into a battery cell, wherein the separator is located between the single-layer positive electrode sheet and the single-layer negative electrode sheet.

Exemplary Embodiment 3

Foamed aluminum is selected as the positive electrode current collector, its porosity is 85%, the average pore size is 2 microns, the thickness is 30 mm, the width is 140 mm, and the height is 78 mm; the mass ratio of the current collector immersed in lithium iron phosphate is 95.5 % positive electrode slurry for 5 times, each time for 20 seconds, to ensure that the inside of the current collector is filled with positive active material; the current collector filled with positive active material is subjected to hot/cold pressing to obtain a single-layer positive electrode sheet.

A carbon foam with a porosity of 70% and a density of 0.44 g/ ^cm3 was selected as the single-layer negative electrode sheet. The thickness of the foamed carbon was 8 mm, the width was 142 mm, the height was 80 mm, and the average value of the micropore diameter was 1.5 mm. micron; inert treatment on the surface of the foamed carbon; copper plating on the single-layer negative electrode tab to increase its weldability.

The single-layer positive electrode sheet, the single-layer negative electrode sheet and the ceramic separator with a thickness of 0.4 mm are assembled into a cell, wherein the separator is located between the single-layer positive electrode sheet and the single-layer negative electrode sheet.

The inventors of the present application also conducted experiments to compare the performance parameters of the cell structure described in the embodiments of the present application with the performance parameters of the conventional cell structure.

test group

The test of the experimental group used the batteries described in the exemplary embodiment 1 of the present application. Since the negative active material is not used, the coulombic efficiency of the first discharge of the cell is similar to that of lithium iron phosphate, the 1C gram capacity of the positive electrode is about 155mAh/g (2.0-3.65V), and the average discharge voltage of the cell is about 3.25V. According to the above parameters, the 1C discharge capacity (2.0-3.65V) of the cell is calculated to be 80.56Ah, the power is about 0.262kWh, and the volume energy density is 498Wh/L.

control group

The control group test uses the cells made by the conventional winding process with the same positive electrode system or formulation and the size of the structural parts. Its cell 1C discharge capacity (2.0-3.65V) is 61.3Ah, the power is 0.196Wh, and the volume energy density is 373Wh/L.

Comparing the data of the experimental group and the control group, it can be obtained that the electrochemical performance of the cells described in the examples of the present application is better than that of the cells made by the conventional winding process, wherein the volume energy of the cells described in the examples of the present application is better The density is 33% higher than the volumetric energy density of cells made using conventional winding processes.

A cell structure provided by the present application uses a single-layer positive electrode sheet, a separator, and a single-layer negative electrode sheet structure, which can simplify the cell production process and control elements, thereby improving cell production efficiency and reducing production costs, and on the other hand. Using a single-layer positive electrode sheet made of three-position porous metal, a single-layer negative electrode sheet made of foam carbon and a ceramic separator with a thickness of millimeters can increase the capacity of the cell, improve the safety performance of the cell, and reduce the self-discharge of the cell.

In conclusion, after reading this detailed disclosure, those skilled in the art will appreciate that the foregoing detailed disclosure may be presented by way of example only, and may not be limiting. Although not explicitly described herein, it will be understood by those skilled in the art that this application is intended to cover various reasonable changes, improvements and modifications to the embodiments. Such changes, improvements and modifications are intended to be suggested by this disclosure and are within the spirit and scope of the exemplary embodiments of this disclosure.

It will be understood that, as used in these examples, the term "and/or" includes any and all combinations of one or more of the associated listed items. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may also be present.

It should also be understood that the terms "comprising", "comprising", "including" and/or "comprising", when used herein, indicate that the recited features, integers, steps, operations, elements and/or components are present, but The presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof is not excluded.

It will also be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, a first element in some embodiments could be termed a second element in other embodiments without departing from the teachings of the present invention. The same reference numerals or the same reference designators denote the same elements throughout the specification.

Claims (6)

1. A cell structure, characterized in that, comprising: A single-layer positive electrode sheet, the single-layer positive electrode sheet includes a three-dimensional porous metal current collector, the positive electrode slurry can be embedded in the pores of the metal current collector, and the thickness of the single-layer positive electrode sheet is 2-100 mm; A single-layer negative electrode sheet, the material of the single-layer negative electrode sheet includes foam carbon, and the thickness of the single-layer negative electrode sheet is 1-50 mm; The ceramic separator is located between the single-layer positive electrode sheet and the single-layer negative electrode sheet, and has a thickness of 0.05-0.5 mm. 2 . The cell structure according to claim 1 , wherein the three-dimensional porous metal is foamed aluminum, and the porosity is 50%-90%. 3 . 3 . The battery core structure according to claim 1 , wherein the porosity of the foamed carbon is 50%-90%, and the diameter of the pores of the foamed carbon is 0.01-10 microns. 4 . 4 . The cell structure according to claim 1 , wherein the porosity of the single-layer positive electrode sheet is 10%-40%. 5 . 5 . The cell structure according to claim 1 , wherein the connecting portion between the carbon foam and the tab further comprises a copper plating layer. 6 . 6. A lithium battery comprising the cell structure according to any one of claims 1-5.

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