CN114512633A - Negative plate and battery comprising same - Google Patents
Negative plate and battery comprising same Download PDFInfo
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- CN114512633A CN114512633A CN202210039435.1A CN202210039435A CN114512633A CN 114512633 A CN114512633 A CN 114512633A CN 202210039435 A CN202210039435 A CN 202210039435A CN 114512633 A CN114512633 A CN 114512633A
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Images
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- 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
-
- 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
-
- 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
- H01M4/362—Composites
- H01M4/366—Composites as layered products
-
- 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
- H01M2004/021—Physical characteristics, e.g. porosity, surface area
-
- 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
- H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
- H01M2004/027—Negative electrodes
Abstract
The invention provides a negative plate and a battery comprising the same, wherein the negative plate comprises a negative current collector, an electrolyte storage layer and a negative active material layer; the electrolyte storage layer adopts the filler with high specific surface area, and the filler with high specific surface area can store a large amount of electrolyte and supplement the deficiency of the electrolyte. The use of the negative plate improves the multiplying power performance and the energy density of the battery, and through the calculation of an electrochemical theory, in the electrode plate, the surface potential of the negative plate close to the diaphragm is lower, the polarization and the electrolyte concentration are uneven, so that the utilization rate of the electrode plate is low, the lithium precipitation risk is higher, and the lithium precipitation risk is reduced, the utilization rate of the electrode plate is improved, and the energy density is improved by constructing an oriented hole fast ion channel on the surface of the electrode plate.
Description
Technical Field
The invention belongs to the technical field of batteries, and particularly relates to a negative plate and a battery comprising the same.
Background
At present, the requirements on the energy density and the quick charging performance of a lithium ion battery are higher and higher, and in order to improve the energy density of the battery, the thickness of a pole piece needs to be increased, however, the increase of the thickness of the pole piece can increase the migration path of electrolyte in the pole piece, and the increase of the migration path can cause the reduction of the rate capability of the pole piece. How to improve the quick charge performance on the premise of ensuring the energy density of the battery becomes a factor for restricting the development of the battery. Researches find that the migration path of the electrolyte can be reduced through the three-dimensional through hole, the transmission rate is improved, but under the condition of high-rate charging, the electrolyte in the through hole cannot be supplemented in time, and the problem of lithium precipitation can be caused.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a negative plate and a battery comprising the negative plate, wherein the negative plate can solve the problems that electrolyte near a through hole cannot be supplemented under a high-rate condition and lithium precipitation can be caused, the rate performance and the energy density of the battery comprising the negative plate are obviously improved, and the cycle performance of the battery is improved.
The invention aims to realize the following technical scheme:
a negative plate comprises a negative current collector, an electrolyte storage layer and a negative active material layer; the electrolyte storage layer is positioned on the surface of one side or two sides of the negative current collector, and the negative active material layer is positioned on the surface of the electrolyte storage layer;
the electrolyte storage layer includes a filler;
the negative electrode active material layer is provided with a first alignment hole.
According to an embodiment of the invention, the specific surface area S ≧ 45m of the filler2/g。
According to the embodiment of the invention, the first orientation hole is constructed in the negative electrode active material layer, and can be used as a fast ion channel for ions (such as lithium ions) to rapidly pass in the charging and discharging process, so that the problems of lithium precipitation on the surface of the negative electrode sheet and the like caused by polarization and uneven concentration of electrolyte are solved; and moreover, an electrolyte storage layer is arranged between the negative active material layer and the negative current collector, so that the electrolyte storage layer can provide the electrolyte for replenishing consumption, and the problem of lithium precipitation around the pore passage is solved.
Further research shows that the specific surface area of the filler in the electrolyte storage layer influences the improvement of concentration polarization near the oriented pores, and different specific surface areas are applied to Li+The requirements for the diffusion capacity are different when the specific surface area S of the filler is greater than or equal to 45m2At the time of/g, the multiplying power performance and the energy density of the battery can be obviously improvedAnd (4) degree. When specific surface area S of the filler<45m2At the time of/g, the stored electrolyte is not enough to compensate the consumed electrolyte, and the problem of lithium precipitation around the pore channel cannot be solved.
According to an embodiment of the invention, the median particle diameter Dv50 of the filler is ≦ 2 μm, preferably 0.1 μm to 2 μm, for example 0.1 μm, 0.2 μm, 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1.0 μm, 1.1 μm, 1.2 μm, 1.3 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.7 μm, 1.8 μm, 1.9 μm or 2 μm.
According to an embodiment of the invention, the filler is selected from at least one of alumina, zirconia, yttria, baria.
According to the embodiment of the invention, the volume percentage of the first alignment holes to the total volume of the negative electrode active material layer is 1 vol% to 50 vol%. Illustratively, the volume percentage of the first alignment hole to the total volume of the anode active material layer is 1 vol%, 2 vol%, 5 vol%, 8 vol%, 10 vol%, 12 vol%, 15 vol%, 18 vol%, 20 vol%, 25 vol%, 30 vol%, 35 vol%, 40 vol%, 45 vol%, 50 vol% or any point in the range of two of the above points.
According to an embodiment of the present invention, the radius R of the first alignment holes is 5 to 150 μm, preferably 10 to 70 μm. Illustratively, the radius R of the first alignment holes is 5 μm, 10 μm, 15 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, or any point in the range consisting of two of the foregoing points.
According to an embodiment of the present invention, the thickness H of the negative electrode active material layer is 10 μm to 200 μm, preferably 20 μm to 100 μm. Illustratively, the thickness H of the anode active material layer is 10 μm, 15 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 200 μm, or any point in the range of two of the foregoing points.
According to an embodiment of the present invention, the negative electrode active materialThe compacted density of the layer is 1.4-1.85 g/m3。
According to an embodiment of the present invention, the thickness h of the electrolyte storage layer is 0.5 to 10 μm, preferably 1 to 3 μm. Illustratively, the thickness h of the electrolyte storage layer is 0.5 μm, 1 μm, 1.5 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, or any point in the range consisting of two of the above points.
According to the embodiment of the invention, the first alignment holes are through holes or non-through holes, and the through holes mean that the first alignment holes penetrate through the anode active material layer, namely, the hole depth of the first alignment holes is equal to the thickness of the anode active material layer; the non-penetrating hole means that the first alignment hole does not penetrate through the anode active material layer, that is, the hole depth of the first alignment hole is smaller than the thickness of the anode active material layer.
According to an embodiment of the present invention, the negative electrode active material has a median particle diameter Dv50 of 1 μm to 30 μm. Illustratively, the negative electrode active material has a median particle diameter Dv50 of 1 μm, 1.5 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 8 μm, 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, 22 μm, 25 μm, 26 μm, 28 μm, 30 μm, or any point in the range consisting of two of the foregoing points.
According to an embodiment of the present invention, the negative electrode sheet further includes a second alignment hole provided on the electrolyte storage layer.
According to the embodiment of the invention, the second orientation hole is constructed in the electrolyte storage layer, and under the condition of sufficient electrolyte, the second orientation hole can also be used as a rapid ion channel for ions (such as lithium ions) to rapidly pass in the charging and discharging process, so that the problems of lithium precipitation on the surface of the negative plate and the like caused by polarization and uneven electrolyte concentration are solved; meanwhile, the rate capability and the energy density of the battery can be improved.
According to the embodiment of the invention, the volume percentage of the second oriented holes in the total volume of the electrolyte storage layer is 1 vol% to 50 vol%. Illustratively, the volume percentage of the second alignment holes to the total volume of the electrolyte storage layer is 1 vol%, 2 vol%, 5 vol%, 8 vol%, 10 vol%, 12 vol%, 15 vol%, 18 vol%, 20 vol%, 25 vol%, 30 vol%, 35 vol%, 40 vol%, 45 vol%, 50 vol% or any point in the range of the two points.
According to an embodiment of the present invention, the radius r of the second alignment holes is 5 μm to 150 μm, preferably 10 μm to 70 μm. Illustratively, the radius r of the second oriented pores is 5 μm, 10 μm, 15 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm or any point in the range consisting of two of the above points.
According to an embodiment of the present invention, the second alignment hole is a through-hole or a non-through-hole, and the through-hole means that the second alignment hole penetrates through the electrolyte solution storage layer, that is, the hole depth of the second alignment hole is equal to the thickness of the electrolyte solution storage layer; the non-penetrating hole means that the second orientation hole does not penetrate through the electrolyte storage layer, that is, the hole depth of the second orientation hole is smaller than the thickness of the electrolyte storage layer.
According to an embodiment of the present invention, the negative electrode sheet further includes third oriented holes disposed on the negative electrode collector.
According to the embodiment of the invention, the third oriented hole is constructed on the negative current collector, and can also be used as a rapid ion channel for ions (such as lithium ions) to rapidly pass in the charging and discharging process, so that the problems of lithium precipitation on the surface of the negative plate and the like caused by polarization and uneven concentration of electrolyte are solved; meanwhile, the rate capability and the energy density of the battery can be improved.
According to the embodiment of the invention, the volume percentage of the third oriented holes in the total volume of the negative electrode current collector is 1 vol% to 50 vol%. Illustratively, the volume percentage of the third oriented hole to the total volume of the negative electrode current collector is 1 vol%, 2 vol%, 5 vol%, 8 vol%, 10 vol%, 12 vol%, 15 vol%, 18 vol%, 20 vol%, 25 vol%, 30 vol%, 35 vol%, 40 vol%, 45 vol%, 50 vol% or any point in the range of the two points.
According to an embodiment of the present invention, the radius L of the third alignment holes is 5 to 150. mu.m, preferably 10 to 70 μm. Illustratively, the radius L of the third oriented pores is 5 μm, 10 μm, 15 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, or any point in the range consisting of two of the foregoing points.
According to an embodiment of the present invention, the third oriented hole is a through-hole or a non-through-hole, where the through-hole refers to a third oriented hole penetrating through the negative electrode current collector, that is, a hole depth of the third oriented hole is equal to a thickness of the negative electrode current collector; the non-penetrating hole means that the third oriented hole does not penetrate through the negative electrode current collector, namely the hole depth of the third oriented hole is smaller than the thickness of the negative electrode current collector.
According to an embodiment of the present invention, the first alignment holes and the second alignment holes are formed by at least one of a template method, a volatile agent pore-forming method, a laser chucking method, a nail plate rolling method, and the like.
According to an embodiment of the present invention, the third alignment hole is formed by at least one of laser drilling, nail plate rolling, and the like.
According to an embodiment of the present invention, the second alignment hole is preferably provided at the same position as the first alignment hole. Specifically, alignment holes are formed in the negative electrode active material layer and the electrolyte storage layer on the surface of the negative electrode current collector, first alignment holes are formed in the negative electrode active material layer, and second alignment holes are formed in the electrolyte storage layer.
According to the embodiment of the invention, the arrangement position of the third orientation hole and the arrangement position of the second orientation hole are the same as the arrangement position of the first orientation hole. Specifically, alignment holes are formed in the negative electrode sheet, first alignment holes are formed in the negative electrode active material layer, second alignment holes are formed in the electrolyte storage layer, and third alignment holes are formed in the negative electrode current collector.
According to an embodiment of the invention, the negative current collector is selected from copper foil or carbon-coated copper foil.
According to an embodiment of the present invention, the thickness of the negative electrode current collector is 5 to 20 μm.
According to an embodiment of the present invention, the anode active material layer includes an anode active material, a conductive agent, and a binder.
According to the embodiment of the invention, the anode active material layer comprises the following components in percentage by mass: 90-99.2 wt% of negative electrode active material, 0.2-4 wt% of conductive agent and 0.6-6 wt% of binder.
According to an embodiment of the present invention, the conductive agent is at least one selected from the group consisting of conductive carbon black, acetylene black, ketjen black, conductive graphite, conductive carbon fiber, carbon nanotube, and metal powder.
According to an embodiment of the present invention, the binder is selected from at least one of polyvinyl alcohol, sodium carboxymethyl cellulose, styrene-butadiene latex, polytetrafluoroethylene, and polyethylene oxide.
According to an embodiment of the present invention, the negative electrode active material is at least one selected from SiOx (0< x <2), lithium-containing transition metal oxide, tin-based composite oxide, artificial graphite, natural graphite, hard carbon, soft carbon, mesophase microspheres, fullerene, and graphene.
According to the embodiment of the invention, the surface density of the negative plate is 0.003-0.015 g/cm2。
The invention also provides a preparation method of the negative plate, which comprises the following steps:
1) respectively preparing slurry for forming a negative electrode active material layer and slurry for forming an electrolyte storage layer;
2) coating the slurry for forming the electrolyte storage layer on the surface of one side or two sides of the negative current collector along the length direction of the negative current collector to form the electrolyte storage layer; coating the slurry for forming the negative electrode active material layer on the surface of the electrolyte storage layer to form a negative electrode active material layer; and rolling, slitting and pore-forming to prepare the negative plate.
According to an embodiment of the present invention, in step 1), the solid content of the slurry for forming the anode active material layer is 40 to 50 wt%. The viscosity of the slurry for forming the negative electrode active material layer is 2000-5000 mPas.
According to an embodiment of the present invention, in the step 1), the solid content of the slurry for forming the electrolyte storage layer is 40 to 50 wt%. The viscosity of the slurry for forming the electrolyte storage layer is 2000-5000 mPa & s.
The invention also provides a battery, which comprises the negative plate.
According to an embodiment of the invention, the battery has a wound or laminated structure.
According to an embodiment of the invention, the battery is a lithium ion battery.
The invention has the beneficial effects that:
according to the negative pole piece and the battery comprising the same, the oriented hole rapid ion channel is constructed on the surface of the pole piece, so that the lithium precipitation risk is reduced, the utilization rate of the pole piece is improved, and the energy density is improved. Furthermore, the surface of the negative plate also comprises an electrolyte storage layer, the electrolyte storage layer adopts a filler with a high specific surface area, the high specific surface area of the filler can store a large amount of electrolyte, the deficiency of the electrolyte is supplemented, and the problems of low utilization rate of the plate, higher lithium precipitation risk and the like caused by non-uniform polarization and electrolyte concentration are avoided. Further research shows that the specific surface area of the filler in the electrolyte storage layer influences the improvement of concentration polarization near the oriented pores, and different specific surface areas are applied to Li+The requirements for the diffusion capacity are different when the specific surface area S of the filler is greater than or equal to 45m2When the specific surface area is/g, the rate capability and the energy density of the battery can be obviously improved.
Drawings
Fig. 1 is a schematic structural diagram of a negative electrode sheet according to embodiment 1 of the present invention.
Fig. 2 is a schematic structural diagram of a negative electrode sheet according to a preferred embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a negative electrode sheet according to a preferred embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to specific examples. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the techniques realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.
The experimental methods used in the following examples are all conventional methods unless otherwise specified; reagents, materials and the like used in the following examples are commercially available unless otherwise specified.
Example 1
80 wt% of the specific surface area is 55m2Mixing alumina particles with the particle size Dv50 of 1 mu m, 5 wt% of conductive carbon black and 15 wt% of polyvinylidene fluoride, adding N-methyl pyrrolidone, stirring and dispersing to prepare slurry, namely electrolyte storage layer slurry.
Preparing cathode slurry by taking graphite as a cathode active material: mixing and stirring 96.8% of negative active material, 1.2% of conductive agent (conductive carbon black) and 2% of binder (styrene butadiene rubber) with water to prepare negative active material layer slurry, wherein the viscosity of the slurry is 2000-5000 mPa & s, and the solid content is 40-50%.
Coating electrolyte storage layer slurry and negative active material layer slurry on a negative current collector by using double-layer coating equipment, wherein the electrolyte storage layer is coated on the negative current collector, the negative active material layer is coated on the electrolyte storage layer, a negative plate with the electrolyte storage layer being 3 microns thick and the negative active material layer being 50 microns thick is obtained after drying and rolling, and a first orientation hole with the radius R of 25 microns is constructed on the negative active material layer by adopting a pulse laser pore-forming method, wherein the volume of the first orientation hole accounts for 20-25 vol% of the total volume of the negative active material layer. The first orientation holes are through holes, that is, the hole depth of the first orientation holes is equal to the thickness of the negative electrode active material layer, and the specific structure is shown in fig. 1.
Preparing positive electrode slurry by using a positive electrode active material: mixing 96% of positive electrode active substance (lithium cobaltate), 2.5% of conductive agent (conductive carbon black) and 1.5% of binder (PVDF) with NMP according to the mass ratio, and stirring to obtain positive electrode slurry, wherein the viscosity of the slurry is 2000-7000 mPa & s, and the solid content is 70-80%. And (3) coating the anode slurry on the surfaces of the two sides of the anode current collector after passing through a screen mesh, and drying and rolling to obtain the anode plate.
And rolling, die cutting and slitting the obtained positive and negative pole pieces, winding and assembling into a roll core, packaging with an aluminum plastic film after a short circuit test is qualified, baking in an oven to remove moisture until the moisture reaches a moisture standard required by liquid injection, injecting electrolyte, aging for 24-48 h, and completing primary charging by a hot pressing formation process to obtain the activated battery cell.
Examples 2 to 7
The other operations are the same as example 1, except that: after drying and rolling, the thickness h of the electrolyte storage layer, the specific surface area S of the filler and the radius R of the first orientation hole are different, and are specifically shown in Table 1.
Comparative example 1
The other operations are the same as example 1, except that: and (3) not carrying out pore-forming treatment, namely drying and rolling to obtain a negative plate with the thickness of the electrolyte storage layer being 3 microns and the thickness of the negative active material layer being 50 microns, and assembling the negative plate into the lithium ion battery.
Comparative example 2
The other operations are the same as example 1, except that: and (3) not carrying out pore-forming treatment and not comprising an electrolyte storage layer, namely coating the negative active material layer slurry on a negative current collector by using coating equipment, wherein the negative active material layer is coated on the negative current collector, drying and rolling to obtain a negative plate with the thickness of 50 mu m of the negative active material layer, and assembling the negative plate into the lithium ion battery.
Comparative example 3
The other operations are the same as example 1, except that: and the electrolyte storage layer is not included, namely the negative active material layer slurry is coated on a negative current collector by using coating equipment, wherein the negative active material layer is coated on the negative current collector, a negative plate with the thickness of 50 mu m of the negative active material layer is obtained after drying and rolling, and the negative plate is assembled into the lithium ion battery after pore forming.
The cells prepared in the above examples and comparative examples are charged at a rate of 0.5C, and the ratio of the energy E discharged at the rate of 0.5C to the cell volume V is the energy density ED-Wh·L-1。
The cells prepared in the above examples and comparative examples were charged at a rate of 3C, discharged at a rate of 1C, subjected to a life test of 700 cycles, and tested for cell capacity retention rate.
The cells prepared in the above examples and comparative examples were charged at 5C rate, discharged at 0.5C rate, and the cells were dissected after 20 cycles of charge and discharge to check the lithium deposition on the surface of the negative electrode.
Table 1 results of performance test of lithium ion batteries of examples and comparative examples
The above results show that the cathode plate prepared according to the invention improves the rate capability and energy density of the battery compared with the cathode plate prepared in the conventional manner, and can effectively solve the problems of low utilization rate and surface lithium precipitation of the cathode plate of the battery with high energy density under the fast charging condition.
Specifically, the negative electrode sheet of example 1 solves the problems of cell lithium deposition and cycle retention rate compared to comparative example 1; compared with the comparative example 2, the energy density is improved on the premise of ensuring that lithium is not separated out; comparative example 3 illustrates the improvement in cell lithiation performance of the electrolyte reservoir compared to example 1 by lithiating the pore negative electrode.
On the basis of the embodiment 1, the embodiments 2 to 7 respectively optimize the energy density and the cycle retention rate; further research shows that when the electrolyte storage layer is too thick (as in example 6), the energy density loss of the pole piece is large, and the polarization of the pole piece is large due to insufficient conductive capacity of the pole piece; when the specific surface area of the filler is too low (as in example 7), the problems of cell lithiation and energy density increase are not significantly improved.
The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiment. Therefore, any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The negative plate is characterized by comprising a negative current collector, an electrolyte storage layer and a negative active material layer; the electrolyte storage layer is positioned on the surface of one side or two sides of the negative current collector, and the negative active material layer is positioned on the surface of the electrolyte storage layer;
the electrolyte storage layer includes a filler;
the negative electrode active material layer is provided with a first alignment hole.
2. The negative electrode sheet according to claim 1, wherein the specific surface area S of the filler is 45m or more2/g；
And/or the radius R of the first orientation hole is 5-150 μm;
and/or the volume percentage of the first orientation hole accounts for 1 vol% -50 vol% of the total volume of the negative electrode active material layer.
3. A negative electrode sheet according to claim 1, wherein the median particle diameter Dv50 of the filler is 2 μm or less;
and/or the thickness H of the negative electrode active material layer is 10-200 μm;
and/or the thickness h of the electrolyte storage layer is 0.5-10 μm.
4. The negative electrode sheet of claim 1, wherein the filler is at least one selected from the group consisting of alumina, zirconia, yttria, and baria.
5. Negative electrode sheet according to any one of claims 1 to 4, characterized in that it further comprises a second oriented hole provided on the electrolyte storage layer.
6. The negative plate according to claim 5, wherein the volume percentage of the second oriented holes to the total volume of the electrolyte storage layer is 1 vol% to 50 vol%;
and/or the radius r of the second orientation hole is 5-150 μm.
7. The negative electrode sheet according to any one of claims 1 to 4, further comprising third oriented holes, wherein the third oriented holes are disposed on the negative electrode current collector.
8. The negative plate according to claim 7, wherein the volume percentage of the third oriented pores to the total volume of the negative current collector is 1 vol% to 50 vol%;
and/or the radius L of the third orientation hole is 5-150 μm.
9. The negative electrode sheet according to any one of claims 1 to 4, wherein the negative electrode active material layer comprises a negative electrode active material, a conductive agent, and a binder;
and/or the mass percentage of each component in the negative electrode active material layer is as follows: 90-99.2 wt% of negative electrode active material, 0.2-4 wt% of conductive agent and 0.6-6 wt% of binder.
10. A battery comprising the negative electrode sheet of any one of claims 1 to 9.
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