CN114300645A - Negative plate, preparation method thereof and lithium ion battery - Google Patents
Negative plate, preparation method thereof and lithium ion battery Download PDFInfo
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- CN114300645A CN114300645A CN202111509457.1A CN202111509457A CN114300645A CN 114300645 A CN114300645 A CN 114300645A CN 202111509457 A CN202111509457 A CN 202111509457A CN 114300645 A CN114300645 A CN 114300645A
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Abstract
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a negative plate, a preparation method thereof and a lithium ion battery. The cathode plate has two layers of coatings, and the second active slurry layer on the outermost surface is provided with the phase change capsule coated by the carbon material, so that the cathode plate forms a gradient with porosity gradually reduced from outside to inside, the extraction of lithium ions and the infiltration of electrolyte are improved, the energy density and the rate capability of the lithium ion battery are improved, and meanwhile, the phase change capsule can relieve the temperature change of the cathode plate and improve the safety performance of the lithium ion battery.
Description
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a negative plate, a preparation method of the negative plate and a lithium ion battery.
Background
In recent years, with the rapid development of electric automobiles, electronic equipment and large-scale power grids, the requirements on batteries in the fields of power batteries and consumer electronic batteries are higher and higher, and the requirements on high quick charge, high capacity and high safety are generally expected to be met.
The patent CN113363418A realizes the pore gradient change of thick coating pole pieces by regulating the solid content of slurry and adopting double-layer coating, is beneficial to improving the capacity density and the rate capability of the lithium ion battery, but is limited by the slurry formula and the structural design, and is difficult to improve the safety performance of the lithium ion battery.
Disclosure of Invention
One of the objects of the present invention is: aiming at the defects of the prior art, the negative pole piece is provided with two layers of coatings, has higher energy density and rate capability, can relieve the temperature change of the pole piece and improves the safety performance of the lithium ion battery.
In order to achieve the purpose, the invention adopts the following technical scheme:
the utility model provides a negative pole piece, includes the negative pole mass flow body, sets up in the first active slurry layer on the at least one surface of negative pole mass flow body, sets up in the second active slurry layer on first active slurry layer surface, second active slurry layer includes the phase transition capsule of carbon element material cladding, the phase transition capsule includes bag core and the wall material of cladding in bag core surface, the bag core is phase transition material.
The phase change capsule coated by the carbon material is arranged in the second active slurry layer, so that the porosity of the pole piece can be increased, the diffusion speed of lithium ions is increased, the multiplying power performance is improved, meanwhile, the phase change capsule can relieve the temperature change of the pole piece, the safety performance of the lithium ion battery is improved, the phase change capsule is coated by the carbon material, the heat conductivity is improved, the heat generated by rapid discharge is better relieved, and the safety performance of the battery is improved; and due to the hydrophobic characteristic of the carbon material, a large number of pores are easily formed in the negative pole piece in the baking process, so that the diffusion speed of lithium ions is increased, and the multiplying power performance is improved.
Preferably, the grain diameter of the phase change capsule coated by the carbon material is 5-20 μm.
Preferably, the phase change material is one or more of aluminum ammonium sulfate dodecahydrate, sodium acetate trihydrate, paraffin, stearic acid, palmitic acid, trihydroxymethyl ethane, and 2-amino-2-methyl-1, 3-propanediol. Wherein the phase change temperature of the phase change material is 55-110 ℃. The phase transition temperature of the dodecacrystalline water aluminum ammonium sulfate is 93 ℃, the phase transition temperature of the sodium acetate trihydrate is 58 ℃, the phase transition temperature of the stearic acid is 63 ℃, the phase transition temperature of the palmitic acid is 69 ℃, the phase transition temperature of the trihydroxymethyl ethane is 81 ℃, and the phase transition temperature of the 2-amino-2-methyl-1, 3-propanediol is 57 ℃.
Wherein the thickness of the negative current collector is 5-30 μm.
Preferably, the thickness of the first active paste layer is 80-150 μm and/or the thickness of the second active paste layer is 80-150 μm. The first washability slurry layer and the second active slurry layer use thick coating, which can increase energy density.
Preferably, the first active slurry layer comprises the following raw materials in parts by weight: 70-95 parts of first negative electrode active material, 1-5 parts of first conductive agent, 1-10 parts of first binder, 1-5 parts of first dispersing agent and 80-100 parts of first solvent.
Preferably, the second active slurry layer comprises the following raw materials in parts by weight: 70-95 parts of a second negative electrode active material, 1-5 parts of a second conductive agent, 1-10 parts of a second binder, 1-5 parts of a second dispersing agent, 80-100 parts of a second solvent and 2-15 parts of a phase change capsule coated by a carbon material.
The second purpose of the invention is: aiming at the defects of the prior art, the preparation method of the negative plate is provided, is simple to operate and easy to control, and can be used for batch production.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of a negative plate comprises the following steps:
step S1, taking the first negative electrode active material, the first conductive agent, the first binder, the first dispersing agent and the first solvent, adding the first negative electrode active material, the first conductive agent, the first binder and the first dispersing agent into the first solvent, stirring and mixing to obtain first slurry;
step S2, taking a second negative electrode active substance, a second conductive agent, a second binder, a second dispersing agent, a phase change capsule coated by a carbon material and a second solvent, adding the second negative electrode active substance, the second conductive agent, the second binder, the second dispersing agent and the phase change capsule coated by the carbon material into the second solvent, stirring and mixing to obtain a second slurry;
step S3, taking a negative current collector, coating the first slurry on at least one surface of the negative current collector, and drying to form a first active slurry layer to prepare a substrate;
and step S4, coating the second slurry on the surface of the first active slurry layer, and drying to form a second active slurry layer to obtain the negative plate.
Preferably, the preparation method of the carbon material coated phase-change capsule comprises the following steps:
step A1, taking the phase change capsule and a third solvent, and dissolving the phase change capsule in the third solvent to obtain a phase change capsule dispersion liquid;
a2, measuring graphene oxide dispersion liquid, dripping the graphene oxide dispersion liquid into the phase change capsule dispersion liquid, heating and stirring, washing and drying to obtain the pretreated micro-gel;
and step A3, adding the pretreated microgel into hydroiodic acid, heating, reducing, and washing to obtain the phase-change capsule coated with the carbon material.
Specifically, the third solvent is deionized water, the mass concentration of the graphene oxide dispersion solution is 2-5mg/ml, the graphene oxide dispersion solution is added in a drop-by-drop manner, the mixture is continuously stirred for 1 hour at 55 ℃, the obtained graphene oxide-coated microcapsules are filtered, the microcapsules are alternately washed for 3 times by using distilled water and ethanol solution, and the microcapsules are dried in an oven for 24 hours at 50 ℃. And reducing the obtained graphene oxide coated micro-gel with hydroiodic acid in an oven at 90 ℃ for 6 hours, and then alternately washing with distilled water and ethanol solution for 3 times to obtain a graphene coated microcapsule, namely the carbon material coated phase-change capsule.
Preferably, the method for manufacturing the phase change capsule comprises the steps of:
step B1, measuring polyvinyl alcohol and a fourth solvent, dissolving the polyvinyl alcohol in the fourth solvent, and heating to obtain a first solution;
step B2, taking the phase change material and the surfactant, mixing the phase change material and the surfactant, and heating, stirring and pre-emulsifying to obtain an organic oil phase mixed solution;
step B3, adding the first solution into the organic oil phase mixed solution and stirring to obtain an oil-in-water emulsion;
and step B4, measuring ethyl orthosilicate and acetic acid solution, and adding the ethyl orthosilicate and the acetic acid solution into the oil-in-water emulsion dropwise to react to obtain the phase-change capsule.
Specifically, the method for manufacturing the phase-change capsule takes paraffin as a phase-change material to prepare the phase-change capsule as an example:
(1) dissolving 1.5g of polyvinyl alcohol in 98.5mL of distilled water, heating to 70 ℃ and fully dissolving the polyvinyl alcohol;
(2) mixing 9.2g of paraffin and 3.0g of mixed surfactant (the mass ratio of span 80 to tween 80 is 0.45:0.55) to form organic oil phase mixed solution, heating to 70 ℃, rotating at 200r/min, and stirring at low speed to pre-emulsify the core material;
(3) adding a polyvinyl alcohol aqueous solution into the organic oil phase mixed solution, and mechanically emulsifying the mixture at a stirring speed of 600r/min to form an oil-in-water O/W emulsion;
(4) while stirring, 2.0g of sodium chloride solution (2.5mol/L) was added to the emulsion to stabilize the system;
(5) after stirring for 30 minutes, 15g of ethyl orthosilicate and 0.2g of acetic acid solution (the mass fraction is 10.0 percent) are successively added into the emulsion system drop by drop to start the hydrolysis and condensation reaction of the ethyl orthosilicate;
(6) after the addition, the reaction mixture was stirred at a stirring speed of 300r/min at a temperature of 55.0 ℃ for 2 hours.
Wherein the weight part ratio of the polyvinyl alcohol to the phase-change material is 0.5-5: 5-15.
The third purpose of the invention is that: in view of the deficiencies of the prior art, a lithium ion battery with high energy density, charging capability and safety is provided.
In order to achieve the purpose, the invention adopts the following technical scheme:
a lithium ion battery comprises the negative plate. The lithium ion battery comprises a positive plate, a diaphragm, electrolyte, a shell and the negative plate, wherein the positive plate and the negative plate are separated by the diaphragm, and the shell is used for installing the positive plate, the diaphragm, the negative plate and the electrolyte.
The active material layer coated on the current collector of the positive plate can be, but is not limited to, an active material of a chemical formula such as LiaNixCoyMzO2-bNb(wherein a is more than or equal to 0.95 and less than or equal to 1.2, x>0, y is more than or equal to 0, z is more than or equal to 0, and x + y + z is 1,0 is more than or equal to b and less than or equal to 1, M is selected from one or more of Mn and Al, N is selected from one or more of F, P and S), and the positive electrode active material can also be selected from one or more of LiCoO (lithium LiCoO), but not limited to2、LiNiO2、LiVO2、LiCrO2、LiMn2O4、LiCoMnO4、Li2NiMn3O8、LiNi0.5Mn1.5O4、LiCoPO4、LiMnPO4、LiFePO4、LiNiPO4、LiCoFSO4、CuS2、FeS2、MoS2、NiS、TiS2And the like. The positive electrode active material may be further modified, and the method of modifying the positive electrode active material is known to those skilled in the art, for example, the positive electrode active material may be modified by coating, doping, and the like, and the material used in the modification may be one or a combination of more of Al, B, P, Zr, Si, Ti, Ge, Sn, Mg, Ce, W, and the like. And the positive electrode current collector is generally a structure or a part for collecting current, and the positive electrode current collector may be any material suitable for being used as a positive electrode current collector of a lithium ion battery in the field, for example, the positive electrode current collector may include, but is not limited to, a metal foil and the like, and more specifically, may include, but is not limited to, an aluminum foil and the like.
And the separator may be various materials suitable for lithium ion battery separators in the art, and for example, may be one or a combination of more of polyethylene, polypropylene, polyvinylidene fluoride, aramid, polyethylene terephthalate, polytetrafluoroethylene, polyacrylonitrile, polyimide, polyamide, polyester, natural fiber, and the like, including but not limited thereto.
The lithium ion battery also comprises electrolyte, and the electrolyte comprises an organic solvent, electrolyte lithium salt and an additive. Wherein the electrolyte lithium salt may be LiPF used in a high-temperature electrolyte6And/or LiBOB; or LiBF used in low-temperature electrolyte4、LiBOB、LiPF6At least one of; or LiBF used in anti-overcharge electrolyte4、LiBOB、LiPF6At least one of, LiTFSI; may also be LiClO4、LiAsF6、LiCF3SO3、LiN(CF3SO2)2At least one of (1). And the organic solvent may be a cyclic carbonate including PC, EC; or chain carbonates including DFC, DMC, or EMC; and also carboxylic acid esters including MF, MA, EA, MP, etc. And additives include, but are not limited to, film forming additives, conductive additives, flame retardant additives, overcharge prevention additives, control of H in the electrolyte2Additives for O and HF content, additives for improving low-temperature properties, and additives for improving low-temperature propertiesAt least one of functional additives.
Wherein, the shell is any one of an aluminum plastic film and stainless steel.
Compared with the prior art, the invention has the beneficial effects that: the cathode plate has two layers of coatings, and the second active slurry layer on the outermost surface is provided with the phase change capsule coated by the carbon material, so that the cathode plate forms a gradient with porosity gradually reduced from outside to inside, the extraction of lithium ions and the infiltration of electrolyte are improved, the energy density and the rate capability of the lithium ion battery are improved, meanwhile, the phase change capsule can relieve the temperature change of the cathode plate and improve the safety performance of the lithium ion battery, the phase change capsule is coated by the carbon material to improve the heat conduction performance, better relieve the heat generated by rapid discharge and improve the safety performance of the battery; and due to the hydrophobic characteristic of the carbon material, a large number of pores are easily formed in the negative pole piece in the baking process, so that the diffusion speed of lithium ions is increased, and the multiplying power performance is improved.
Drawings
Fig. 1 is one of the structural schematic diagrams of the negative electrode sheet of the present invention.
Fig. 2 is a second schematic structural diagram of the negative electrode sheet of the present invention.
Wherein: 1. a negative current collector; 2. a first active paste layer; 3. a second active paste layer.
Detailed Description
The present invention will be described in further detail below with reference to specific embodiments and drawings, but the embodiments of the present invention are not limited thereto.
Example 1
As shown in fig. 1, a negative plate includes a negative current collector 1, a first active slurry layer 2 disposed on a surface of the negative current collector 1, and a second active slurry layer 3 disposed on a surface of the first active slurry layer 2, where the second active slurry layer 3 includes a phase change capsule coated with a carbon material, the phase change capsule includes a capsule core and a wall material coated on an outer surface of the capsule core, and the capsule core is made of a phase change material.
Example 2
As shown in fig. 2, the negative electrode sheet includes a negative electrode current collector 1, a first active slurry layer 2 disposed on two side surfaces of the negative electrode current collector 1, and a second active slurry layer 3 disposed on a surface of the first active slurry layer 2, where the second active slurry layer 3 includes a phase change capsule coated with a carbon material, the phase change capsule includes a capsule core and a wall material coated on an outer surface of the capsule core, and the capsule core is made of a phase change material.
Example 3
1. Preparation of a first slurry: according to parts by weight, 95 parts of graphite active material, 1.5 parts of carbon black Super-P, 2.5 parts of styrene butadiene rubber and 1.5 parts of sodium carboxymethylcellulose are sequentially added into 100 parts of deionized water, and after the materials are stirred at a high speed for 3 hours, the viscosity is 4200mPa & s, and the solid content is 51%.
2. Preparation of a second slurry: according to parts by weight, 95 parts of graphite active material, 1.5 parts of carbon black Super-P, 2.5 parts of styrene butadiene rubber and 1.5 parts of sodium carboxymethylcellulose are sequentially added into 100 parts of deionized water, 5 parts of graphite-coated paraffin with the particle size of 10 mu m, namely the phase-change capsule coated by the carbon material, are added, and after the mixture is stirred at a high speed for 3 hours, the viscosity is 4400mPa & s, and the solid content is 53%.
3. Preparing a negative pole piece: coating first slurry on the upper surface of a copper foil of a 6-micron negative current collector 1 by using a double-layer coating machine, drying to obtain a first active slurry layer 2 with the thickness of 130 microns, coating second slurry on the surface of the first active slurry layer 2, drying to obtain a second active slurry layer 3 with the thickness of 160 microns, and baking, rolling, splitting and welding tabs to obtain a negative plate.
4. Preparing a positive pole piece: mixing 98.2 wt% of lithium cobaltate, 0.5 wt% of Super-P, 1.3 wt% of polyvinylidene fluoride and N-methyl pyrrolidone into slurry, uniformly coating the slurry on a 10 mu m aluminum foil, and baking, rolling, slitting and welding tabs to obtain the positive pole piece.
5. Preparing an electrolyte: mixing lithium hexafluorophosphate (LiPF)6) The electrolyte solution was obtained by dissolving the above-mentioned materials in a mixed solvent of dimethyl carbonate (DEC), Ethylene Carbonate (EC), Ethyl Methyl Carbonate (EMC) and diethyl carbonate (DEC) (the mass ratio of the four was 3:5:1: 2).
6. Preparing a lithium ion battery: taking the prepared positive pole piece, negative pole piece and polyethylene/polypropylene porous film with the thickness of 8 mu m as diaphragms, preparing the cell with the model of 575166P in a winding mode, wherein the capacity and the area of the negative pole piece are more than 8% of those of the positive pole piece, packaging the positive pole piece and the negative pole piece through an aluminum-plastic film to form a soft package cell, and then injecting, forming and grading the liquid.
Example 4
The difference from example 3 is the preparation of the first and second pastes for the negative electrode:
1. preparation of a first slurry: according to parts by weight, 93 parts of silicon-carbon active material, 2 parts of carbon nano tube, 3 parts of polyacrylic acid and 1 part of sodium carboxymethylcellulose are sequentially added into 110 parts of deionized water, and after stirring for 3 hours at a high speed, the viscosity is 3500mPa & s, and the solid content is 48%.
2. Preparation of a second slurry: 93 parts of silicon-carbon active material, 2 parts of carbon nano tube, 3 parts of polyacrylic acid and 1 part of sodium carboxymethylcellulose are sequentially added into 110 parts of deionized water according to parts by weight, 8 parts of graphite-coated paraffin with the particle size of 15 mu m, namely the phase-change capsule coated by the carbon material, and after stirring at high speed for 3 hours, the viscosity is 4100mPa & s, and the solid content is 50%.
The rest is the same as embodiment 3, and the description is omitted here.
Example 5
The difference from example 3 is that: preparation of a second slurry for negative electrode:
according to parts by weight, 95 parts of graphite, 1.5 parts of carbon black Super-P, 2.5 parts of styrene butadiene rubber, 1.5 parts of sodium carboxymethylcellulose and 10 parts of carbon-coated octadecane phase-change microcapsules with the particle size of 8 mu m are sequentially added into 100 parts of deionized water, and after stirring at high speed for 3 hours, the viscosity is 3900mPa & s, and the solid content is 54%.
The rest is the same as embodiment 3, and the description is omitted.
Example 6
The difference from example 3 is that: the second active slurry layer 3 comprises the following raw materials in parts by weight: 75 parts of a second negative electrode active material, 2 parts of a second conductive agent, 4 parts of a second binder, 2 parts of a second dispersing agent, 95 parts of a second solvent and 3 parts of a phase change capsule coated by a carbon material.
The rest is the same as embodiment 3, and the description is omitted here.
Example 7
The difference from example 3 is that: the second active slurry layer 3 comprises the following raw materials in parts by weight: 85 parts of a second negative electrode active material, 2 parts of a second conductive agent, 5 parts of a second binder, 3 parts of a second dispersing agent, 100 parts of a second solvent and 8 parts of a phase change capsule coated by a carbon material.
The rest is the same as embodiment 3, and the description is omitted here.
Example 8
The difference from example 3 is that: the second active slurry layer 3 comprises the following raw materials in parts by weight: 95 parts of a second negative electrode active material, 4 parts of a second conductive agent, 6 parts of a second binder, 5 parts of a second dispersing agent, 98 parts of a second solvent and 10 parts of a phase change capsule coated by a carbon material.
The rest is the same as embodiment 3, and the description is omitted here.
Example 9
The difference from example 4 is that: the particle size of the phase change capsule is 17 μm, the thickness of the first active paste layer 2 is 80 μm, and the thickness of the second active paste layer is 100 μm.
The rest is the same as embodiment 4, and the description is omitted here.
Example 10
The difference from example 4 is that: the particle size of the phase change capsule is 8 μm, the thickness of the first active paste layer 2 is 95 μm, and the thickness of the second active paste layer is 110 μm.
The rest is the same as embodiment 4, and the description is omitted here.
Example 11
The difference from example 4 is that: the particle size of the phase change capsule is 6 μm, the thickness of the first active paste layer 2 is 120 μm, and the thickness of the second active paste layer is 140 μm.
The rest is the same as embodiment 4, and the description is omitted here.
Comparative example 1: coating negative slurry on the upper surface of the copper foil with the thickness of 6 mu m by a coating machine, drying, baking, rolling, splitting and welding a tab to obtain a negative pole piece with the thickness of 300 mu m.
And (3) performance testing: the performance tests of the pole pieces and batteries prepared in the above examples 1 to 11 and comparative example 1 were carried out, and the test structures are recorded in table 1.
1. And (3) rate performance test:
standing the lithium ion battery to be tested in an environment of 25 +/-2 ℃ for 30 minutes, respectively carrying out constant current charging at a multiplying power of 0.2C and 3C until the voltage is 4.45V, then carrying out constant voltage charging until the current is 0.02C, and recording the percentage of the charging capacity in the constant current stage of the 3C charging multiplying power.
2. Testing the temperature change of the battery core:
the temperature probe is placed at the geometric center of the maximum surface of the battery, the lithium ion battery to be tested is placed still for 30 minutes in an environment of 25 +/-2 ℃, the battery is charged from the battery in an empty state to 4.45V at a constant current with a multiplying power of 3C, then the battery is charged at a constant voltage to 0.02C, and the difference between the maximum temperature of the probe and the initial temperature recorded at the beginning is in the period.
TABLE 1
As can be seen from table 1, the negative electrode sheet prepared by the invention has better rate capability and safety performance compared with the negative electrode sheet of comparative example 1, and can effectively alleviate temperature change of the electrode sheet and avoid short circuit caused by excessive high temperature. From the comparison of examples 3, 4 and 5, when the raw materials of the first slurry are set as follows: 95 parts of graphite active material, 1.5 parts of carbon black Super-P, 2.5 parts of styrene butadiene rubber, 1.5 parts of sodium carboxymethylcellulose and 100 parts of deionized water; the battery prepared from the second slurry comprises 95 parts of graphite active material, 1.5 parts of carbon black Super-P, 2.5 parts of styrene butadiene rubber, 1.5 parts of sodium carboxymethylcellulose, 10 parts of carbon-coated n-octadecane phase-change microcapsules with the particle size of 8 mu m and 100 parts of deionized water. Compared with examples 4 and 9-11, when the particle size of the phase-change capsule is 10 μm, the thickness of the first active paste layer 2 is 130 μm, and the thickness of the second active paste layer is 160 μm, the prepared battery has better performance, because the proper particle size of the phase-change capsule is matched with the thicknesses and porosity of the first active paste layer 2 and the second active paste layer 3, the negative plate has better electrolyte wettability and rate capability, the proper particle size does not affect the moving speed of ions, the wettability of the electrolyte is improved, and the de-intercalation of lithium ions is facilitated.
Variations and modifications to the above-described embodiments may also occur to those skilled in the art, which fall within the scope of the invention as disclosed and taught herein. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious improvement, replacement or modification made by those skilled in the art based on the present invention is within the protection scope of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Claims (10)
1. The negative plate is characterized by comprising a negative current collector, a first active slurry layer arranged on at least one surface of the negative current collector, and a second active slurry layer arranged on the surface of the first active slurry layer, wherein the second active slurry layer comprises a phase change capsule coated by a carbon material, the phase change capsule comprises a capsule core and a wall material coated on the outer surface of the capsule core, and the capsule core is made of the phase change material.
2. The negative electrode sheet according to claim 1, wherein the carbon material-coated phase change capsule has a particle size of 5 to 20 μm.
3. The negative plate of claim 1, wherein the phase change material is one or more of aluminum ammonium sulfate dodecahydrate, sodium acetate trihydrate, paraffin, stearic acid, palmitic acid, trihydroxymethyl ethane, 2-amino-2-methyl-1, 3-propanediol.
4. The negative electrode sheet according to claim 1, 2 or 3, wherein the thickness of the first active paste layer is 80-150 μm and/or the thickness of the second active paste layer is 80-150 μm.
5. The negative electrode sheet according to claim 1, wherein the first active slurry layer comprises the following raw materials in parts by weight: 70-95 parts of first negative electrode active material, 1-5 parts of first conductive agent, 1-10 parts of first binder, 1-5 parts of first dispersing agent and 80-100 parts of first solvent.
6. The negative electrode sheet according to claim 1, wherein the second active paste layer comprises the following raw materials in parts by weight: 70-95 parts of a second negative electrode active material, 1-5 parts of a second conductive agent, 1-10 parts of a second binder, 1-5 parts of a second dispersing agent, 80-100 parts of a second solvent and 2-15 parts of a phase change capsule coated by a carbon material.
7. The method for preparing a negative electrode sheet according to any one of claims 1 to 6, comprising the steps of:
step S1, taking the first negative electrode active material, the first conductive agent, the first binder, the first dispersing agent and the first solvent, adding the first negative electrode active material, the first conductive agent, the first binder and the first dispersing agent into the first solvent, stirring and mixing to obtain first slurry;
step S2, taking a second negative electrode active substance, a second conductive agent, a second binder, a second dispersing agent, a phase change capsule coated by a carbon material and a second solvent, adding the second negative electrode active substance, the second conductive agent, the second binder, the second dispersing agent and the phase change capsule coated by the carbon material into the second solvent, stirring and mixing to obtain a second slurry;
step S3, taking a negative current collector, coating the first slurry on at least one surface of the negative current collector, and drying to form a first active slurry layer to obtain a substrate;
and step S4, coating the second slurry on the surface of the first active slurry layer, and drying to form a second active slurry layer to obtain the negative plate.
8. The method for preparing a negative electrode sheet according to claim 7, wherein the method for preparing the phase-change capsule coated with the carbon material comprises the following steps:
step A1, taking the phase change capsule and a third solvent, and dissolving the phase change capsule in the third solvent to obtain a phase change capsule dispersion liquid;
a2, measuring graphene oxide dispersion liquid, dripping the graphene oxide dispersion liquid into the phase change capsule dispersion liquid, heating and stirring, washing and drying to obtain the pretreated micro-gel;
and step A3, adding the pretreated microgel into hydroiodic acid, heating, reducing, and washing to obtain the phase-change capsule coated with the carbon material.
9. The method for preparing a negative electrode plate according to claim 8, wherein the method for manufacturing the phase change capsule comprises the following steps:
step B1, measuring polyvinyl alcohol and a fourth solvent, dissolving the polyvinyl alcohol in the fourth solvent, and heating to obtain a first solution;
step B2, taking the phase change material and the surfactant, mixing the phase change material and the surfactant, and heating, stirring and pre-emulsifying to obtain an organic oil phase mixed solution;
step B3, adding the first solution into the organic oil phase mixed solution and stirring to obtain an oil-in-water emulsion;
and step B4, measuring ethyl orthosilicate and acetic acid solution, and adding the ethyl orthosilicate and the acetic acid solution into the oil-in-water emulsion dropwise to react to obtain the phase-change capsule.
10. A lithium ion battery comprising the negative electrode sheet according to any one of claims 1 to 6.
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Cited By (2)
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| CN116814221A (en) * | 2022-11-29 | 2023-09-29 | 广州纳诺新材料技术有限公司 | Phase-change microcapsule, high-safety lithium battery and preparation method thereof |
| CN117219780A (en) * | 2023-08-25 | 2023-12-12 | 浙江柔震科技有限公司 | Carbon-coated current collector and preparation method thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060063066A1 (en) * | 2004-08-06 | 2006-03-23 | Seungdon Choi | Battery system containing phase change material-containing capsules in interior configuration thereof |
| CN1995264A (en) * | 2006-12-06 | 2007-07-11 | 清华大学深圳研究生院 | Silicon dioxde coated phase-change energy-storage material microcapsule preparation method |
| KR20160120874A (en) * | 2015-04-09 | 2016-10-19 | 임진명 | Cathode Having Double Coating Structure for Lithium Secondary Battery to Improve Cycle Performance and Method of Preparing the Same |
| KR20170031387A (en) * | 2015-09-11 | 2017-03-21 | 주식회사 엘지화학 | Electrode Comprising Active Material Layers Having Active Material Particles of Different Average Particle Sizes |
| CN107384327A (en) * | 2017-07-25 | 2017-11-24 | 华南理工大学 | Organic phase-change microcapsule of graphene oxide doped silica inorganic wall material cladding and preparation method thereof |
| US20200153041A1 (en) * | 2018-03-27 | 2020-05-14 | Lg Chem, Ltd. | Complex Solid Electrolyte Membrane for All-Solid-State Battery and All-Solid-State Battery Including Same |
| CN111849424A (en) * | 2020-08-05 | 2020-10-30 | 哈尔滨工业大学 | Phase-change heat storage material with microsphere structure and preparation method thereof |
| CN112490406A (en) * | 2020-12-02 | 2021-03-12 | 欣旺达电动汽车电池有限公司 | Electrode pole piece and lithium ion battery |
-
2021
- 2021-12-10 CN CN202111509457.1A patent/CN114300645A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060063066A1 (en) * | 2004-08-06 | 2006-03-23 | Seungdon Choi | Battery system containing phase change material-containing capsules in interior configuration thereof |
| CN1995264A (en) * | 2006-12-06 | 2007-07-11 | 清华大学深圳研究生院 | Silicon dioxde coated phase-change energy-storage material microcapsule preparation method |
| KR20160120874A (en) * | 2015-04-09 | 2016-10-19 | 임진명 | Cathode Having Double Coating Structure for Lithium Secondary Battery to Improve Cycle Performance and Method of Preparing the Same |
| KR20170031387A (en) * | 2015-09-11 | 2017-03-21 | 주식회사 엘지화학 | Electrode Comprising Active Material Layers Having Active Material Particles of Different Average Particle Sizes |
| CN107384327A (en) * | 2017-07-25 | 2017-11-24 | 华南理工大学 | Organic phase-change microcapsule of graphene oxide doped silica inorganic wall material cladding and preparation method thereof |
| US20200153041A1 (en) * | 2018-03-27 | 2020-05-14 | Lg Chem, Ltd. | Complex Solid Electrolyte Membrane for All-Solid-State Battery and All-Solid-State Battery Including Same |
| CN111849424A (en) * | 2020-08-05 | 2020-10-30 | 哈尔滨工业大学 | Phase-change heat storage material with microsphere structure and preparation method thereof |
| CN112490406A (en) * | 2020-12-02 | 2021-03-12 | 欣旺达电动汽车电池有限公司 | Electrode pole piece and lithium ion battery |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116814221A (en) * | 2022-11-29 | 2023-09-29 | 广州纳诺新材料技术有限公司 | Phase-change microcapsule, high-safety lithium battery and preparation method thereof |
| CN116814221B (en) * | 2022-11-29 | 2024-01-23 | 广州纳诺新材料技术有限公司 | Phase-change microcapsule, high-safety lithium battery and preparation method thereof |
| CN117219780A (en) * | 2023-08-25 | 2023-12-12 | 浙江柔震科技有限公司 | Carbon-coated current collector and preparation method thereof |
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