CN114079048A - Negative pole piece and lithium ion battery - Google Patents
Negative pole piece and lithium ion battery Download PDFInfo
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- CN114079048A CN114079048A CN202010830248.6A CN202010830248A CN114079048A CN 114079048 A CN114079048 A CN 114079048A CN 202010830248 A CN202010830248 A CN 202010830248A CN 114079048 A CN114079048 A CN 114079048A
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/36—Selection of substances as active materials, active masses, active liquids
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- H—ELECTRICITY
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- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/058—Construction or manufacture
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
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Abstract
The invention provides a negative pole piece, which comprises a current collector and an active layer, wherein the active layer comprises a first active material, a second active material, a binder and a conductive agent, and the gram capacity of the first active material is higher than that of the second active material; the volume expansion rate of the first active material is higher than the volume expansion rate of the second active material; the content of the binder is decreased progressively along the direction far away from the current collector; and in the direction far away from the current collector, the contents of the conductive agent and the binder in the secondary active layer of each layer are gradually reduced, and the plurality of secondary active layers comprise a first active layer, a second active layer and a third active layer. Therefore, the active layer of the battery can be prevented from falling off, the conductivity of the negative pole piece is improved, the cycle performance and the battery capacity of the battery are improved, the capacity exertion of the active material is facilitated, the active layer contacting the current collector has more binders, the larger volume expansion of the first active material can be inhibited, the falling off of the active layer is prevented, and the cycle performance of the battery can be improved.
Description
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a negative electrode plate and a lithium ion battery.
Background
The lithium ion battery is widely applied to 3C digital products due to the characteristics of high energy density, long cycle life, no memory effect, adjustable shape and size and the like. Along with the national advocation of energy conservation and emission reduction, the lithium ion battery is more and more important to the new energy industry and is widely applied to automobiles as a new energy source.
When the lithium ion battery is charged, lithium ions are extracted from the positive electrode, enter the electrolyte, pass through the diaphragm to reach the surface of the negative electrode, and then are embedded into micropores of the negative electrode. In the prior art, a graphite material is used as a negative electrode material of a lithium ion battery, and the theoretical specific capacity of the graphite material is only 372mAh-1It is difficult to satisfy the further development of lithium ion batteries in terms of capacity, and high-capacity negative electrode materials are the main direction of future development, such as silicon materials due to their abundant reserves in the earth's crust and 4200mah.g-1The ultrahigh theoretical specific capacity is considered to be one of the most promising lithium ion battery negative electrode materials, but the silicon negative electrode material has a serious problem of volume expansion in the lithium removal/insertion process, so that the active material is pulverized and separated from a current collector, and the performance of the battery is difficult to ensure.
Currently, the main methods for solving the volume expansion of the silicon negative electrode material are as follows: firstly, a silicon oxide material or a silicon carbon material with relatively small expansion is adopted. And secondly, optimizing the electrode formula, and adding more binders to ensure that the active material cannot be separated from the current collector. However, only with respect to the improvement of the negative electrode material and the binder, although the expansion of the negative electrode of the high-capacity battery can be suppressed to a certain extent, the problem of large volume expansion of the high-capacity negative electrode sheet is still outstanding, and the requirements of the battery application on the cycle performance and the battery thickness cannot be met.
Disclosure of Invention
The invention aims to solve the problem that a negative pole piece with high capacity has larger volume expansion in battery cycle in the prior art, and provides the negative pole piece and a lithium ion battery.
In order to solve the technical problem, the invention provides a negative electrode plate which is characterized by comprising a current collector and an active layer, wherein the active layer comprises a first active material, a second active material, a binder and a conductive agent, and the gram capacity of the first active material is higher than that of the second active material; the active layer is positioned on the surface of the current collector, and the volume expansion rate of the first active material is higher than that of the second active material; the content of the binder decreases in a direction away from the current collector.
Optionally, the first active material has a gram capacity in the range of 1000mAg-1To 3000mAg-1The second active material has a gram capacity in the range of 300mAg-1To 360mAg-1。
Optionally, the active layer includes secondary active layers stacked in sequence in a direction away from the current collector.
Optionally, in a direction away from the current collector, the content of the first active material in the active layer decreases progressively, the content of the second active material in the active layer increases progressively, and the content of the conductive agent in the secondary active layer decreases progressively from layer to layer.
Optionally, the plurality of secondary active layers comprises a first active layer, a second active layer, and a third active layer; the first active layer contains ingredients with the mass parts ranging from 60 to 85 parts of first active material, 5 to 30 parts of second active material, 8 to 15 parts of binder and 5 to 10 parts of conductive agent; the second active layer contains ingredients in the following numerical ranges of 30-50 parts by mass of a first active material, 40-60 parts by mass of a second active material, 5-8 parts by mass of a binder and 5-8 parts by mass of a conductive agent; the third active layer contains ingredients, and the mass percentage numerical range of the ingredients is that the first active material is 5-30 parts, the second active material is 60-90 parts, the binder is 0.5-5 parts, and the conductive agent is 0.5-5 parts.
Optionally, the first active material comprises one or more of a silicon-based material comprising one or more of silicon, a silicon alloy, a silicon monoxide, and a silicon carbon compound, a tin-based material comprising one or more of tin, tin oxide, and tin dioxide, and a metal oxide material comprising one or more of iron oxide, manganese oxide, zinc oxide, and cobalt oxide.
Optionally, the second active material comprises one or more of a carbon-based material and a lithium titanate material, the carbon-based material comprising one or more of a graphite material, a soft carbon material, a hard carbon material, and mesocarbon microbeads.
Optionally, the conductive agent comprises one or more of carbon black, ketjen carbon, acetylene black, graphene, single-walled carbon nanotubes, and multi-walled carbon nanotubes.
Optionally, the binder comprises one or more of carboxymethyl cellulose, sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, polyacrylic acid, sodium polyacrylate, lithium polyacrylate, styrene butadiene rubber, polyethylene oxide, polyester, polyamide, and polymethyl methacrylate.
The invention also provides a lithium ion battery which comprises a positive pole piece, a diaphragm, electrolyte and the negative pole piece.
In the negative pole piece provided by the invention, in the direction far away from the current collector, the content of the first active material in the active layer is decreased progressively, and the content of the second active material is distributed progressively. Therefore, during the battery cycle, the first active material expands due to volume, so that more pores appear in the active layer close to the current collector, the electrolyte is favorably infiltrated into the active layer close to the current collector, the capacity of the active material at the current collector is favorably exerted, and the battery capacity is improved; on the other hand, the active layer contacting the current collector contains a large amount of binder, so that the first active material is prevented from being expanded in volume, the active layer is prevented from falling off, and the cycle performance of the battery can be improved.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic view of a multilayer structure of a plurality of sequentially stacked secondary active layers of a negative electrode tab according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The negative pole piece provided by the embodiment of the invention comprises a current collector and an active layer, wherein the active layer comprises a first active material, a second active material, a binder and a conductive agent, and the gram capacity of the first active material is higher than that of the second active material; the active layer is positioned on the surface of the current collector, and the volume expansion rate of the first active material is higher than that of the second active material; the content of the binder decreases in a direction away from the current collector.
The binder in the active layer contacting the current collector is more, so that the larger volume expansion of the first active material can be inhibited, the active layer can be prevented from falling off, and the cycle performance of the battery can be improved; in the battery cycle, the first active material expands due to volume, so that more pores appear in the active layer close to the current collector, the electrolyte is favorably infiltrated into the active layer close to the current collector, and the capacity of the active material at the current collector is favorably exerted, so that the battery performance is improved.
In one embodiment, the first active material has a gram-capacity in the range of 1000mA hg-1To 3000mA h g-1The gram capacity of the second active material is in the range of 300mA hr g-1To 360mA h g-1。
In one embodiment, the active layers include secondary active layers stacked in sequence in a direction away from the current collector.
In one embodiment, in a direction away from the current collector, the content of the first active material in the active layer decreases progressively, the content of the second active material in the active layer increases progressively, and the content of the conductive agent in the secondary active layer decreases progressively from layer to layer. In the active layer contacting or approaching to the current collector, the content of the first active material is high, so that the capacity requirement of the battery can be met; the content of the conductive agent is high, so that the conductivity of the pole piece can be improved, and the capacity exertion of the active material is facilitated.
In an embodiment, referring to a schematic diagram of a multilayer structure of a plurality of sequentially stacked secondary active layers of a negative electrode tab shown in fig. 1, the plurality of secondary active layers include a first active layer, a second active layer and a third active layer; the first active layer contains ingredients with the mass parts ranging from 60 to 85 parts of first active material, 5 to 30 parts of second active material, 8 to 15 parts of binder and 5 to 10 parts of conductive agent; the second active layer contains ingredients in the following numerical ranges of 30-50 parts by mass of a first active material, 40-60 parts by mass of a second active material, 5-8 parts by mass of a binder and 5-8 parts by mass of a conductive agent; the third active layer contains ingredients, and the mass percentage numerical range of the ingredients is that the first active material is 5-30 parts, the second active material is 60-90 parts, the binder is 0.5-5 parts, and the conductive agent is 0.5-5 parts.
In the first active layer, the content of the first active material is high, the content of the second active material is low, the mixed material has poor conductivity and large volume expansion, and the content of the corresponding binder and the corresponding conductive agent is higher, so that the falling of the active layer is prevented, the conductivity of a pole piece is improved, and the cycle performance of the battery is improved; along with the distance from the current collector, the content of the first active material in the active layer is reduced, the content of the second active material is increased, the conductivity of the mixed material is increased, the volume expansion is reduced, the content of the corresponding binder and the content of the corresponding conductive agent are also reduced, and the energy density of the battery is favorably improved.
The above compounds are part of the claimed invention, but are not limited thereto and should not be construed as limiting the invention.
In one embodiment, the first active material comprises one or more of a silicon-based material comprising one or more of silicon, a silicon alloy, silicon monoxide, and a silicon carbon compound, a tin-based material comprising one or more of tin, tin oxide, and tin dioxide, and a metal oxide material comprising one or more of iron oxide, manganese oxide, zinc oxide, and cobalt oxide.
In one embodiment, the second active material comprises one or more of a carbon-based material comprising one or more of a graphite material, a soft carbon material, a hard carbon material, and mesocarbon microbeads and a lithium titanate material.
In one embodiment, the conductive agent comprises one or more of carbon black, ketjen carbon, acetylene black, graphene, single-walled carbon nanotubes, and multi-walled carbon nanotubes.
In one embodiment, the binder comprises one or more of carboxymethylcellulose, sodium carboxymethylcellulose, lithium carboxymethylcellulose, polyacrylic acid, sodium polyacrylate, lithium polyacrylate, styrene butadiene rubber, polyethylene oxide, polyester, polyamide, and polymethyl methacrylate.
The invention also provides a lithium ion battery which comprises a positive pole piece, a diaphragm, electrolyte and the negative pole piece.
The present invention will be further illustrated by the following examples.
Example 1
The embodiment is used for explaining the negative pole piece and the preparation method thereof disclosed by the invention.
80 parts by mass: 20 as a first active material, a mixture of silica as a first active material and a graphite material as a second active material, the active material being mixed with a conductive material SP, a binder material PAA in a ratio of 85: 5: 10 parts by mass of the first negative electrode slurry L1 was prepared. 50 parts by mass: 50 as a first active material, a mixture of silica as a first active material and a natural graphite material as a second active material, the other active material being mixed with a conductive material SP, a binder material SBR, a thickener CMC in a ratio of 95: 5: 2: 3 parts by mass were mixed to prepare second negative electrode slurry L2. The method comprises the steps of firstly coating first negative electrode slurry L1 on a current collector to obtain a first active material layer, wherein the current collector is a copper foil, after drying and pressing, coating second negative electrode slurry L2 on the first active material layer, drying and pressing, and then performing double-sided coating to obtain a multilayer negative electrode sheet S1. And preparing a battery B1 by using the negative pole piece and the matched positive pole.
Example 2
This embodiment is used to describe another negative electrode sheet and a method for manufacturing the negative electrode sheet disclosed in the present invention.
Mixing the following components in percentage by weight of 70: 30 as a first active material, a commercial 1200 silicon carbon as a second active material, graphite mixture as an active material, the active material mixed with a conductive material SP, a binder material PAA in a ratio of 80: 6.5: the mass ratio of 13.5 was used to prepare first negative electrode slurry L1. Mixing the following components in percentage by weight of 80: 20 as a first active material a commercial 1200 silicon carbon as a second active material graphite mixture as another active material mixed with a conductive material SP, a binder material SBR, a thickener CMC in a ratio of 95: 5: 2: 3, preparing second negative electrode slurry L2, coating the first negative electrode slurry L1 on copper foil to obtain a first active material layer, drying and pressing, coating the second negative electrode slurry L2 on the first active material layer, drying and pressing, and coating the two sides to obtain the multilayer negative electrode sheet S2. And preparing a battery B2 by using the negative pole piece and the matched positive pole.
Example 3
This embodiment is used to describe another negative electrode sheet and a method for manufacturing the negative electrode sheet disclosed in the present invention.
Mixing the following components in percentage by weight of 80: 20 a first active material, using a graphite mixture of tin and a second active material as an active material, the active material was mixed with a conductive material SP, a binder material PAA in a ratio of 85: 5: 10, a first negative electrode slurry L1 was prepared, and the mass ratio of the artificial graphite material to the conductive material SP, the binder material SBR, and the thickener CMC was adjusted to 95: 5: 2: 3, coating the first negative electrode slurry L1 on copper foil to obtain a first active material layer, drying and pressing, coating the second negative electrode slurry L2 on the first active material layer, drying and pressing, and coating the two sides of the first active material layer to obtain the multilayer negative electrode sheet S3. And preparing a battery B3 by using the negative pole piece and the matched positive pole.
Example 4
Mixing the following components in percentage by weight of 80: 20 as a first active material, commercial silica was mixed with graphite as a second active material as an active material, and the active material was mixed with a conductive material SP, a binder material PAA in a ratio of 85: 5: 10, preparing first negative electrode slurry L1; mixing the following components in percentage by weight of 60: 40 as another active material mixed with a graphite material, the active material was mixed with a conductive material SP, a binder material PAA in a ratio of 90: 4: 6, preparing second negative electrode slurry L2 according to the mass ratio; mixing the following components in percentage by weight of 30: 70 as a second active material, a mixture of artificial graphite and natural graphite as another active material, which is mixed with a conductive material SP, a binder material SBR, a thickener CMC in a ratio of 98: 1: 0.5: and (3) preparing a third negative electrode slurry L3 according to the mass ratio of 0.5, sequentially coating the negative electrode slurries L1, L2 and L3 on copper foil, drying and pressing, and then coating the two sides of the copper foil to obtain the multilayer negative electrode plate S4. And preparing a battery B4 by using the negative pole piece and the matched positive pole.
Example 5
Mixing the following components in percentage by weight of 80: 20 as a first active material, a mixture of commercial silica and graphite as a second active material, as an active material, the active material being mixed with a conductive material SP, a binder material PAA in a ratio of 85: 7: 10, preparing first negative electrode slurry L1; mixing the following components in percentage by weight of 50: 60 of a commercial silica material and a graphite material as an active material, the active material was mixed with a conductive material SP and a binder material PAA in a ratio of 90: 6: 6, preparing second negative electrode slurry L2 according to the mass ratio; mixing the following components in percentage by weight of 30: 70 of a commercial silica material mixed with a graphite material as another active material, the active material was mixed with a conductive material SP, a binder material SBR, a thickener CMC in a ratio of 98: 1: 0.5: and (3) preparing a third negative electrode slurry L3 according to the mass ratio of 0.5, sequentially coating the negative electrode slurries L1, L2 and L3 on an electro-copper foil to obtain a multi-layer active material layer, drying and pressing, and then coating the two sides of the multi-layer active material layer to obtain the multi-layer negative electrode sheet S5. And preparing a battery B5 by using the negative pole piece and the matched positive pole.
Comparative example 1
This example serves to illustrate by comparison the properties of S1, S2, S3, and S4 prepared in examples 1-4 of the present disclosure.
Mixing the following components in percentage by weight of 50: 50 as a second active material, a mixture of artificial graphite and natural graphite as a negative active material, and mixing the active material with a conductive material SP, a binder material SBR, and a thickener CMC in a ratio of 95: 5: 2: 3, preparing a second negative electrode slurry L1 in a weight ratio of 80: 20 as a first active material, a mixture of commercial silica as a first active material and graphite as a second active material as a first negative electrode active material, the active material mixed with a conductive material SP, a binder material PAA in a ratio of 85: 5: 10, coating the first negative electrode slurry L1 on a copper foil of an electrode current collector, drying and pressing, coating the second negative electrode slurry L2 on the first active material layer, drying and pressing, and coating the two sides of the first active material layer to obtain the multilayer negative electrode sheet C1. The negative pole piece and the matched positive pole are used for preparing a battery P1.
The negative electrode sheet prepared in comparative example 1 is characterized in that the first active material layer is formed at a position away from the copper foil, and the second active material layer is formed at a position close to the copper foil.
Comparative example 2
Mixing the following components in percentage by weight of 80: 20 as a first active material, a mixture of commercial silica and graphite as a second active material as a negative active material, the active material was mixed with a conductive material SP, a binder material PAA in a ratio of 85: 5: 10, preparing a negative electrode slurry L1, coating the negative electrode slurry L1 on a copper foil, and drying and pressing to obtain a negative electrode sheet C2. The negative pole piece and the matched positive pole are used for preparing a battery P2.
The negative electrode plate prepared in the comparative example 2 does not show the characteristic of the change of the content of the slurry components, that is, the first active material and the second active material are mixed and coated, and the binder is PAA.
Comparative example 3
Mixing the following components in percentage by weight of 80: 20 as a first active material, a mixture of commercial silica and graphite as a second active material as a negative electrode active material, and the active material was mixed with a conductive material SP, a binder material SBR, and a thickener CMC in a ratio of 95: 5: 2: 3, preparing second negative electrode slurry L1, coating the negative electrode slurry L1 on an electrode current collector copper foil, and drying and pressing to obtain a negative electrode pole piece C3. The negative pole piece and the matched positive pole are used for preparing a battery P3.
The negative electrode plate prepared in comparative example 3 does not show the characteristic of the change of the slurry component content, that is, the first active material and the second active material are mixed and coated, and the binder is SBR and CMC.
Performance testing
The following performance tests were performed on the negative electrode sheet and the lithium ion battery prepared in the above examples 1 to 5 and comparative examples 1 to 3
1) Peel Strength test
The prepared negative electrode sheets S1, S2, S3, S4, C1, C2 and C3 were subjected to a peel strength test according to a conventional test.
The peel strength test method adopted in the experiment is that one side of the prepared negative pole piece is stuck by a strong adhesive tape and then fixed between two steel plate clamps, and then the negative pole piece and the steel plate clamps are pulled apart by a universal tensile tester, and the tensile strength of the negative pole piece and the steel plate clamps represents the bonding strength. The calculation method is as follows, because the pulling force is uniform, the distance of pulling apart in unit time is also constant, so the pulling force is only related to the width of the bonding surface, and if the pulling force of unit length in the width direction is f, namely the pulling force intensity, namely the bonding intensity, then the pulling force is:
i.e., F/x.
2) Porosity test
The prepared negative electrode plates S1, S2, S3, S4, C1, C2 and C3 are subjected to a porosity test according to a conventional test.
The porosity test method adopted in the experiment comprises the steps of cutting a pole piece into small round pieces with certain sizes according to a certain direction, weighing the mass of each small round piece, measuring the volume of each small round piece, calculating the compaction density of the pole piece, and calculating the porosity of the pole piece according to the following formula (the porosity belongs to the inherent porosity of a negative pole piece before the negative pole piece is assembled into a battery).
Porosity 1-p(compaction)/ρ(true)
The test results of the present invention are shown in Table 1.
TABLE 1
Cycle performance test
The batteries B1, B2, B3, B4, P1, P2, and P3 prepared as described above were subjected to normal-temperature electrochemical charge and discharge test in the number of cycles of 500 cycles in accordance with the conventional test.
The results of the cycling tests of the present invention are filled in table 2.
TABLE 2
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. A negative electrode plate is characterized by comprising a current collector and an active layer, wherein the active layer comprises a first active material, a second active material, a binder and a conductive agent, and the gram capacity of the first active material is higher than that of the second active material;
the active layer is positioned on the surface of the current collector, and the volume expansion rate of the first active material is higher than that of the second active material; the content of the binder decreases in a direction away from the current collector.
2. The negative electrode tab of claim 1, wherein the first active material has a gram capacity in the range of 1000mAg-1To 3000mAg-1The second active material has a gram capacity in the range of 300mAg-1To 360mAg-1。
3. The negative electrode tab of claim 1, wherein the active layer comprises secondary active layers stacked in sequence in a direction away from the current collector.
4. The negative electrode sheet of claim 3, wherein the content of the first active material in the active layer decreases progressively and the content of the second active material increases progressively in a direction away from the current collector, and the content of the conductive agent in the secondary active layer decreases progressively from layer to layer.
5. The negative electrode tab of claim 3, wherein the secondary active layer comprises a first active layer, a second active layer, and a third active layer;
the first active layer contains ingredients with the mass parts ranging from 60 to 85 parts of first active material, 5 to 30 parts of second active material, 8 to 15 parts of binder and 5 to 10 parts of conductive agent;
the second active layer contains ingredients in the following numerical ranges of 30-50 parts by mass of a first active material, 40-60 parts by mass of a second active material, 5-8 parts by mass of a binder and 5-8 parts by mass of a conductive agent;
the third active layer contains ingredients, and the mass percentage numerical range of the ingredients is that the first active material is 5-30 parts, the second active material is 60-90 parts, the binder is 0.5-5 parts, and the conductive agent is 0.5-5 parts.
6. The negative electrode tab of claim 1, wherein the first active material comprises one or more of a silicon-based material comprising one or more of silicon, a silicon alloy, silicon monoxide, and a silicon carbon compound, a tin-based material comprising one or more of tin, tin oxide, and tin dioxide, and a metal oxide material comprising one or more of iron oxide, manganese oxide, zinc oxide, and cobalt oxide.
7. The negative electrode sheet of claim 1, wherein the second active material comprises one or more of a carbon-based material comprising one or more of a graphite material, a soft carbon material, a hard carbon material, and mesocarbon microbeads and a lithium titanate material.
8. The negative electrode tab of claim 1, wherein the conductive agent comprises one or more of carbon black, ketjen carbon, acetylene black, graphene, single-walled carbon nanotubes, and multi-walled carbon nanotubes.
9. The negative electrode tab of claim 1, wherein the binder comprises one or more of carboxymethyl cellulose, sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, polyacrylic acid, sodium polyacrylate, lithium polyacrylate, styrene butadiene rubber, polyethylene oxide, polyester, polyamide, and polymethyl methacrylate.
10. A lithium ion battery comprising a positive electrode sheet, a separator, an electrolyte and the negative electrode sheet of any one of claims 1 to 9.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114678491A (en) * | 2022-04-12 | 2022-06-28 | 浙江极氪智能科技有限公司 | Negative pole piece, preparation method thereof and electrochemical device |
| CN114824164A (en) * | 2022-06-20 | 2022-07-29 | 比亚迪股份有限公司 | Lithium ion battery cathode, preparation method thereof and lithium ion battery |
| CN114864870A (en) * | 2022-06-10 | 2022-08-05 | 中创新航科技(合肥)有限公司 | Negative pole piece and lithium ion battery comprising same |
| CN114914393A (en) * | 2022-05-20 | 2022-08-16 | 珠海冠宇电池股份有限公司 | Negative plate and lithium ion battery |
| CN115295764A (en) * | 2022-07-29 | 2022-11-04 | 江苏正力新能电池技术有限公司 | Negative pole piece, preparation method thereof and secondary battery |
| CN116885104A (en) * | 2023-03-13 | 2023-10-13 | 宁德时代新能源科技股份有限公司 | Negative electrode plate, secondary battery and electricity utilization device |
| WO2024026654A1 (en) * | 2022-08-02 | 2024-02-08 | 宁德时代新能源科技股份有限公司 | Negative electrode sheet, secondary battery and electric apparatus |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114678491A (en) * | 2022-04-12 | 2022-06-28 | 浙江极氪智能科技有限公司 | Negative pole piece, preparation method thereof and electrochemical device |
| CN114678491B (en) * | 2022-04-12 | 2023-09-05 | 浙江极氪智能科技有限公司 | Negative electrode plate, preparation method thereof and electrochemical device |
| CN114914393A (en) * | 2022-05-20 | 2022-08-16 | 珠海冠宇电池股份有限公司 | Negative plate and lithium ion battery |
| CN114864870A (en) * | 2022-06-10 | 2022-08-05 | 中创新航科技(合肥)有限公司 | Negative pole piece and lithium ion battery comprising same |
| CN114864870B (en) * | 2022-06-10 | 2024-05-28 | 中创新航科技(合肥)有限公司 | Negative electrode piece and lithium ion battery comprising same |
| CN114824164A (en) * | 2022-06-20 | 2022-07-29 | 比亚迪股份有限公司 | Lithium ion battery cathode, preparation method thereof and lithium ion battery |
| CN114824164B (en) * | 2022-06-20 | 2022-10-18 | 比亚迪股份有限公司 | Lithium ion battery cathode, preparation method thereof and lithium ion battery |
| CN115295764A (en) * | 2022-07-29 | 2022-11-04 | 江苏正力新能电池技术有限公司 | Negative pole piece, preparation method thereof and secondary battery |
| WO2024026654A1 (en) * | 2022-08-02 | 2024-02-08 | 宁德时代新能源科技股份有限公司 | Negative electrode sheet, secondary battery and electric apparatus |
| CN116885104A (en) * | 2023-03-13 | 2023-10-13 | 宁德时代新能源科技股份有限公司 | Negative electrode plate, secondary battery and electricity utilization device |
| CN116885104B (en) * | 2023-03-13 | 2023-12-08 | 宁德时代新能源科技股份有限公司 | Negative electrode plate, secondary battery and electricity utilization device |
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