CN115117560A - Lithium-supplementing composite isolating membrane and preparation method and application thereof - Google Patents
Lithium-supplementing composite isolating membrane and preparation method and application thereof Download PDFInfo
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Abstract
The invention discloses a lithium-supplementing composite isolating membrane and a preparation method and application thereofThe layer is coated on one side of the base film facing the anode, and the lithium supplement layer is prepared from a lithium supplement layer material which consists of a lithium-rich material and a bonding agent; the lithium-rich material is Li 2 NiO 2 、Li 3 N、Li 2 O 2 、Li 2 One of S, preferably Li 3 And N is added. The lithium supplementing layer can compensate irreversible lithium ions lost in the charging and discharging processes of the lithium ion battery, so that the lithium ion battery after lithium supplementation has higher initial discharge capacity and first charging and discharging efficiency, and the energy density and the cycle performance of the lithium ion battery are improved; the heat shrinkage performance of the isolating film can be improved, and the temperature resistance and the safety of the isolating film are improved; the preparation method and the use of the lithium-supplement composite isolating membrane have good compatibility with the existing lithium ion battery preparation process, and are suitable for industrial mass production.
Description
Technical Field
The invention relates to the technical field of batteries, in particular to a lithium-supplementing composite isolating membrane and a preparation method and application thereof.
Background
The lithium ion battery has the characteristics of high output voltage, high energy density, long cycle life, environmental friendliness and the like, and is widely applied to the fields of digital electronic products, electric tools, electric vehicles, energy storage and the like. At present, the rapid development of high-capacity battery technology accelerates the commercialization process of lithium ion power batteries, so that the popularization rate of new energy vehicles rapidly rises year by year. When the new energy electric vehicle is pursued, consumers put higher requirements on long endurance performance, cycle performance and the like. Therefore, batteries with higher energy density are developed to meet the increasing demand of long endurance mileage of the market. Currently, alloy negative electrode materials such as silicon-based materials are expected to replace graphite negative electrodes for large-scale commercial application in lithium ion batteries due to higher capacity. However, the problem of low first charge-discharge efficiency of alloy negative electrode materials such as silicon-based materials greatly restricts the full battery capacity, and further influences the improvement of the actual energy density.
In the process of manufacturing the lithium battery, the first charge-discharge efficiency of the battery can be obviously improved by supplementing lithium to the positive electrode and the negative electrode. The lithium supplement method adopted by the current negative electrode mainly comprises the following steps: (1) spraying superfine metal lithium powder on the surface of the negative pole piece to supplement lithium; (2) preparing superfine lithium powder into slurry, and spraying the slurry on the surface of a negative electrode to supplement lithium; (3) transferring the ultrathin metal lithium foil from the base material to a negative plate by a mechanical rolling mode to supplement lithium; (4) depositing gaseous lithium on the surface of the negative pole piece in a magnetron sputtering or thermal evaporation mode; (5) and adding metal lithium powder into the negative electrode mixture for ball milling, and preparing the lithium-supplement negative electrode piece by adopting a dry process.
The lithium supplementing method is complex in operation, poor in compatibility with the current production process and serious in potential safety hazard. Therefore, researchers have focused their attention on the development of lithium supplement for positive electrodes.
The main mode of lithium supplement of the positive electrode is to add Li 2 NiO 2 、Li 3 N、Li 2 O 2 、Li 2 And S and other lithium-rich materials are added into the positive pole piece to achieve the effect of lithium supplement. However, the lithium supplement materials are not only poor in chemical stability, but also have obvious difference in consistency of the coated pole piece because the stability of the positive pole slurry is obviously affected by the addition of the lithium supplement materials in the positive pole homogenizing process.
Disclosure of Invention
In view of the problems in the prior art, one aspect of the present invention provides a lithium supplement composite barrier film, in which a lithium supplement layer is coated on a side of a base film facing a positive electrode, and the lithium supplement layer is composed of a lithium-rich material and a binder. The lithium supplementing layer can compensate irreversible lithium ions lost in the charging and discharging process of the lithium ion battery, so that the lithium ion battery after lithium supplementation has higher initial discharge capacity and first charging and discharging efficiency, the energy density and the cycle performance of the lithium ion battery are improved, the heat shrinkage performance of the isolating film can be improved to a certain extent, and the temperature resistance and the safety of the isolating film are further improved.
The invention also provides a preparation method and application of the lithium ion battery lithium supplement composite isolating membrane.
In order to achieve the above purpose, the following technical scheme is adopted.
The lithium supplement composite isolating membrane comprises a base membrane and a lithium supplement layer, wherein the lithium supplement layer is coated on one side, facing to a positive electrode, of the base membrane, and is prepared from a lithium supplement layer material, and the lithium supplement layer material is composed of a lithium-rich material and a bonding agent.
In a preferred embodiment, the base film is made of any one of polypropylene (PP), Polyethylene (PE), polyvinylidene fluoride (PVDF), Polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), and Polyamide (PA).
In a preferred embodiment of the lithium-doped composite separator, the ratio of the thickness of the base film to the thickness of the lithium-doped layer is (5-30): (1-10) (e.g., 5:1, 5:2, 5:3, 5:4, 5:5, 5:6, 5:7, 5:8, 5:9, 5:10, 10:1, 10:3, 10:5, 10:7, 10:9, 15:1, 15:5, 15:10, 20:1, 20:5, 25:1, 25:4, 25:8, 30:1, 30:7, 30: 10); preferably, the base film has a thickness of 5 to 30 μm (e.g., 7 μm, 10 μm, 15 μm, 20 μm, 25 μm, 27 μm), and the lithium supplement layer has a thickness of 1 to 10 μm (e.g., 2 μm, 4 μm, 5 μm, 7 μm, 9 μm), preferably 1.5 to 8 μm (e.g., 2 μm, 4 μm, 5 μm, 6 μm, 7 μm).
In the above lithium-supplementing composite separator, as a preferred embodiment, the lithium-rich material is Li 2 NiO 2 、Li 3 N、Li 2 O 2 、Li 2 One of S, preferably Li 3 N。
In the conventional technology, when the lithium metal is used as a lithium supplement active substance and the formed composite diaphragm is applied to a battery, the first charge-discharge efficiency, the first discharge capacity, the energy density and the 500-time circulation capacity retention rate at normal temperature and 1C of the prepared lithium ion battery are excellent, but compared with the conventional battery prepared by the diaphragm comprising a PP (polypropylene) base film and an alumina ceramic coating layer, the lithium ion battery has obviously reduced performances in the aspects of needling strength and heat shrinkage rate.
According to the invention, the lithium supplementing layer contains the lithium-rich material, so that irreversible lithium ions lost in the charging and discharging processes of the lithium ion battery can be compensated, the lithium ion battery after lithium supplementation has higher initial discharge capacity and first charging and discharging efficiency, the energy density and the cycle performance of the lithium ion battery are improved, the heat shrinkage performance of the isolating membrane can be improved to a certain extent, and the temperature resistance and the safety of the isolating membrane are further improved.
In addition, the lithium-rich material in the invention is low in price, and compared with the conventional lithium metal supplement material, the cost of the battery can be reduced.
In a preferred embodiment of the lithium-doped composite separator, the lithium-rich material has a particle size of 5nm to 2000nm (e.g., 10nm, 50nm, 100nm, 200nm, 500nm, 600nm, 800nm, 1000nm, 1500nm, 1700nm, 1800nm, 1900 nm).
In a preferred embodiment of the lithium-supplement composite separator, the mass percentage of the lithium-supplement material in the lithium-supplement layer is 1% to 99% (e.g., 5%, 10%, 15%, 20%, 30%, 50%, 60%, 80%, 90%, 95%), preferably 20% to 95% (e.g., 25%, 30%, 40%, 50%, 60%, 80%, 90%), and more preferably 20% to 90% (e.g., 25%, 30%, 40%, 50%, 60%, 80%, 85%).
In a preferred embodiment of the lithium-supplementing composite separator, the binder in the lithium-supplementing layer material is one or more selected from polyvinyl alcohol (PVA), polyvinylidene fluoride (PVDF), polymethyl methacrylate (PMMA), polyethyl methacrylate (PS), polyethylene oxide (PEO), polypropylene oxide (PPO), polyethylene glycol (PEG), nitrile rubber (NBR), Styrene Butadiene Rubber (SBR), sodium carboxymethylcellulose (CMCNa), lithium hydroxymethylcellulose (CMCLi), Polytetrafluoroethylene (PTFE), polyisobutyl methacrylate, polybutyl methacrylate, polyhydroxyethyl methacrylate, polyethyleneglycol dimethacrylate, polymethyl acrylate, polyethyl acrylate, and poly-3-methyl methoxyacrylate.
The second aspect of the invention provides a preparation method of the lithium-supplementing composite isolating membrane, which adopts the following technical scheme:
the preparation method of the lithium-supplementing composite isolating membrane comprises the following steps:
s1, adding the lithium-rich material and the binder into a solvent, and uniformly mixing to obtain a lithium supplement slurry;
and S2, coating the lithium supplement slurry on one side of the base film facing the positive electrode, and drying at the temperature of 35-110 ℃ to obtain the lithium supplement composite film.
Further, in step S1, the mixing is performed in an environment with humidity less than 1% and temperature of 20-30 ℃ (e.g., 22 ℃, 25 ℃, 28 ℃), and the solvent is one selected from N-methylpyrrolidone (NMP), Dimethylformamide (DMF), Diethylformamide (DEF), Dimethylsulfoxide (DMSO), or Tetrahydrofuran (THF).
The third aspect of the invention provides an application of the lithium-supplementing composite isolating membrane.
According to the application of the lithium supplement composite isolating membrane, the lithium supplement composite isolating membrane is matched with a positive plate, a negative plate and electrolyte to prepare a lithium ion battery through lamination or winding, wherein the lithium supplement composite isolating membrane is positioned between the positive plate and the negative plate, and a lithium supplement layer in the lithium supplement composite isolating membrane faces one side of the positive plate.
The preparation method and the use of the lithium ion battery lithium-supplementing composite isolating membrane provided by the invention have good compatibility with the existing lithium ion battery preparation process, and are suitable for industrial mass production.
In the invention, the technical characteristics can be freely combined to form a new technical scheme under the condition of not conflicting with each other.
Compared with the prior art, the invention has the following beneficial technical effects:
1. the lithium supplementing layer can compensate irreversible lithium ions lost in the charging and discharging process of the lithium ion battery, so that the lithium ion battery after lithium supplementation has higher initial discharge capacity and first charging and discharging efficiency, the energy density and the cycle performance of the lithium ion battery are improved, the heat shrinkage performance of the isolating film can be improved, and the temperature resistance and the safety of the isolating film are further improved.
2. The preparation method and the use of the lithium ion battery lithium-supplementing composite isolating membrane provided by the invention have good compatibility with the existing lithium ion battery preparation process, and are suitable for industrial mass production.
3. Compared with the traditional lithium supplement in the positive and negative pole pieces or slurry, the lithium supplement composite isolating membrane provided by the invention has many advantages: a. the cutting machine can flexibly cut positive and negative pole pieces according to the sizes of the pole pieces, is convenient to use, has high material utilization rate, does not waste, and improves the production efficiency of the battery cell; b. the uniform lithium supplement composite isolating membrane can realize efficient, uniform and safe lithium supplement of the cathode material, and has excellent performance and good consistency; c. the storage period of the pole piece for lithium supplement of the lithium supplement composite isolation film phase is longer than that of the pole piece for lithium supplement of the positive pole and the negative pole, and the cost is low; d. compared with lithium supplement by metal lithium, the lithium-ion battery has the advantages of higher safety reliability and remarkable low cost.
Drawings
Fig. 1 is a schematic structural view of a lithium-supplement composite separator in embodiment 1 of the present invention; 1-barrier film base film; 2-a lithium supplement layer; 2-1-a binder in the lithium supplement layer; 2-2-lithium supplement composite material in the lithium supplement layer.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in figure 1, the lithium-supplementing composite isolating membrane provided by the invention is composed of a base membrane 1 and a lithium-supplementing layer 2, wherein in the lithium-supplementing layer 2, a lithium-rich material 2-2 and a binder 2-1 are uniformly distributed in the lithium-supplementing layer 2.
In order to verify the lithium supplementing effect, the lithium supplementing composite isolating membrane and the positive and negative pole pieces of the lithium ion battery are assembled into the battery.
The positive and negative electrode sheets used in all the following examples and comparative examples were the same, wherein NCM811 was used for the positive electrode and SiO/C was used for the negative electrode, and SiO used was an SiO material that was not subjected to lithiation treatment.
The effect testing method related in the embodiment of the invention comprises the following steps:
(1) test for needling Strength
A sheet sample was prepared, fixed under a test jig, and subjected to puncturing using a high-iron tensile machine and a puncturing jig, using a puncturing needle having a diameter of 1mm on a puncturing tester at a speed of 50mm/min, and the puncture strength (in units gf) was calculated as F/9.8 x 1000 when the top puncturing force F after data stabilization was measured.
(2) Heat shrinkage test
The composite separator was cut into square samples 100mm long and 100mm wide, and the Machine Direction (MD) and Transverse Direction (TD) were marked, after which the lengths in the MD and TD directions were measured with a projection tester and noted as L1 and L2, after which the separator was placed in a 90 ℃ forced air oven, taken out after one hour, and the lengths in the MD and TD directions were measured again with a projection tester and noted as L3 and L4.
The heat shrinkage rate of the separator in the MD direction was (L1-L3)/L1 × 100%;
the heat shrinkage in the TD direction of the separator film was (L2-L4)/L2 × 100%.
(3) Capacity test of lithium ion secondary battery
In a 25 ℃ constant temperature box, charging at a constant current of 0.5C multiplying power until the voltage is 4.2V, then charging at a constant voltage of 4.2V until the current is 0.05C, and then discharging at a constant current of 0.2C multiplying power until the voltage is 2.75V, wherein the obtained discharge capacity is the battery capacity.
(4) Normal temperature cycle performance test of lithium ion secondary battery
Performing 0.5C constant current charge and discharge test on 10 ternary lithium batteries at 25 ℃, wherein the charge and discharge voltage range is 2.75-4.2V; charging with constant current at C multiplying power to 4.2V, charging with constant voltage at 4.2V to 0.05C, and discharging with constant current at 1C multiplying power to 2.75V, which is a charge-discharge cycle, and repeating the charge-discharge cycle 500 times.
(5) The capacity retention rate after 500 cycles was equal to the discharge capacity after 500 cycles/the discharge capacity after the first cycle × 100%.
Example 1
As shown in figure 1, the lithium supplement composite isolation membrane comprises a basal membrane (PP membrane, thickness of 12 μm) and a lithium supplement layer with thickness of 2 μm arranged on the side of the basal membrane facing to the positive electrode, wherein the lithium supplement layer is prepared by a lithium supplement layer material which comprises a lithium-rich material Li 3 N and Binder, Li-Rich Material 3 Of NThe particle size is 50nm, and the mass percentage of the particle size in the lithium supplement layer is 70%; the adhesive is PMMA, and the mass percentage of the PMMA in the lithium supplement layer is 30%.
The preparation method of the lithium-supplement composite diaphragm comprises the following steps:
s1, controlling the humidity to be less than 1% and the temperature to be 20-30 ℃, and mixing the 900g of Li rich material 3 And adding N into 3600g of NMP, stirring for 30min, adding 100g of PMMA, and continuously stirring for 3h to obtain the lithium supplement slurry.
And S2, coating the lithium supplementing slurry on the side, facing the anode, of the PP base film with the thickness of 3 microns, and drying the PP base film with the thickness of 10 microns by a rolling oven at the temperature of 75 ℃ to obtain the lithium supplementing composite isolating film, wherein the thickness of a lithium supplementing layer of the dried lithium supplementing composite isolating film is 1.5 microns.
Example 2
The embodiment is based on the technical solution of embodiment 1, and the difference is that: in this example Li 3 The mass percentage of N in the lithium supplement layer is 75%.
Example 3
The embodiment is based on the technical solution of embodiment 1, and the difference is that: in this example Li 3 The mass percentage of N in the lithium supplement layer is 80%.
Example 4
The embodiment is based on the technical solution of embodiment 1, and the difference is that: in this example Li 3 The mass percentage of N in the lithium supplement layer is 85%.
Example 5
The embodiment is based on the technical solution of embodiment 1, and the difference is that: in this example Li 3 The mass percentage of N in the lithium supplement layer is 90%.
Comparative example 1
Based on the technical solution of example 1, the present comparative example replaces the separator in example 1 with a separator including a PP-based film and an alumina ceramic coating layer.
Comparative example 2
This comparative example is based on the solution of example 1, with the following differences: in this comparative example, the separator in example 1 was replaced with a separator including a PP-based film and a lithium supplement layer on the side facing the negative electrode, wherein the lithium supplement layer was composed of metal lithium powder and a binder PMMA with a mass fraction of the binder PMMA of 10%.
Assembling and testing the lithium ion battery:
with the lithium-replenishing composite separator prepared in the above examples 1 to 5 and comparative examples 1 to 2, the positive electrode of the battery uses NCM811 as an active material and uses a 12 μm aluminum foil as a positive electrode current collector; the negative electrode takes SiO/C as an active material, copper foil 6 mu M as a negative current collector, the diaphragm is coated with the lithium supplementing layer, the prepared lithium supplementing composite film is placed between a negative pole piece and a positive pole piece, and a laminate assembly soft package battery, 1M LiPF 6 Preparing a 10Ah soft package battery by using/EC + DEC + DMC (EC, DEC and DMC are in a volume ratio of 1:1:1) as an electrolyte, wherein EC is ethylene carbonate, DEC is diethyl carbonate, and DMC is dimethyl carbonate.
And packaging and standing the battery after liquid injection, performing a first charge-discharge test at a rate of 0.1C/0.1C, recording the first discharge capacity, the first charge-discharge efficiency and the energy density of the battery, and testing the capacity retention rate of the battery after 1C charge-discharge for 500 cycles. Table 1 shows the cycle performance and energy density of the lithium ion batteries of examples 1 to 5 and comparative examples 1 to 2.
TABLE 1 cycle performance and energy density of lithium ion batteries in examples 1 to 5 and comparative examples 1 to 2
And (3) testing results:
compared with the comparative example 1, the lithium-supplement composite diaphragm prepared in the examples 1 to 5 is obviously superior to the lithium ion battery without the lithium-supplement layer in the aspects of the first charge-discharge efficiency, the first discharge capacity, the energy density and the 500-time cycle capacity retention rate at the normal temperature of 1C.
By way of examples 1-5 and comparative example2, it is known that Li 3 The lithium ion battery prepared by applying N-ratio metal lithium as a lithium supplement active substance on a diaphragm has relatively close first charge-discharge efficiency, first discharge capacity, energy density and 500-time cycle capacity retention rate performance at normal temperature and 1C.
And (3) testing the performance of the lithium-supplement composite diaphragm:
in order to verify the performance of the separator in each example of the present invention, the separator and the lithium ion battery prepared in examples 1 to 5 and comparative examples 1 to 2 were subjected to the performance test of the puncture strength and the heat shrinkage rate, and the test results are shown in table 2.
TABLE 2 Properties of composite separators in examples 1 to 5 and comparative examples 1 to 2
And (3) testing results:
compared with the comparative example 2, the lithium supplement composite diaphragms prepared in the examples 1 to 5 are obviously superior to the composite diaphragms adopting metal lithium as the lithium supplement layer in the aspects of the needling strength and the heat shrinkage rate. Meanwhile, from the results of examples 1 to 5, it is understood that Li in the lithium layer is supplemented as 3 The increase of the mass fraction of N and the needling strength and the heat shrinkage rate performance of the lithium-supplement composite diaphragm are continuously improved. In example 5, Li in the lithium layer was added 3 When the mass fraction of N is increased to 90%, the properties in the needle punching strength and the heat shrinkage rate are close to those of comparative example 1.
Therefore, as can be seen from tables 1 and 2, in the present invention, Li is used 3 When the formed composite diaphragm is applied to a battery, the prepared lithium ion battery has excellent first charge-discharge efficiency, first discharge capacity, energy density and 500-time cycle capacity retention rate performance at normal temperature of 1C, and also has excellent performances in the aspects of puncture strength and heat shrinkage rate compared with the case that metal lithium is used as a lithium supplement active substance.
The above-mentioned embodiments are only specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are within the scope of the present invention and the disclosure.
Claims (10)
1. The lithium supplement composite isolating membrane is characterized by comprising a base membrane and a lithium supplement layer, wherein the lithium supplement layer is coated on one side of the base membrane facing a positive electrode, the lithium supplement layer is prepared from a lithium supplement layer material, and the lithium supplement layer material is composed of a lithium-rich material and a bonding agent.
2. The lithium supplementing composite isolating membrane according to claim 1, wherein the base membrane is made of any one of polypropylene, polyethylene, polyvinylidene fluoride, polytetrafluoroethylene, polyvinyl chloride, or polyamide.
3. The lithium-filling composite isolating membrane as claimed in claim 1, wherein the ratio of the thickness of the base membrane to the thickness of the lithium-filling layer is (5-30): 1-10; preferably, the thickness of the base film is 5-30 μm, and the thickness of the lithium supplement layer is 1-10 μm, preferably 1.5-8 μm.
4. The lithium-supplementing composite separator according to claim 1, wherein said lithium-rich material is Li 2 NiO 2 、Li 3 N、Li 2 O 2 、Li 2 One of S, preferably Li 3 N。
5. The lithium-supplementing composite isolating membrane according to claim 1, wherein the lithium-rich material has a particle size of 5nm to 2000 nm.
6. The lithium-supplementing composite isolating membrane according to any one of claims 1 to 5, wherein the mass percentage of the lithium-supplementing material in the lithium-supplementing layer is 1 to 99%, preferably 20 to 95%, and more preferably 20 to 90%.
7. The lithium supplement composite isolation membrane according to any one of claims 1 to 5, wherein the binder in the lithium supplement layer material is one or more of polyvinyl alcohol, polyvinylidene fluoride, polymethyl methacrylate, polyethyl methacrylate, polyethylene oxide, polypropylene oxide, polyethylene glycol, nitrile rubber, styrene butadiene rubber, sodium hydroxymethyl cellulose, lithium hydroxymethyl cellulose, polytetrafluoroethylene, polyisobutyl methacrylate, polybutyl methacrylate, polyhydroxyethyl methacrylate, polyethylene glycol dimethacrylate, polymethyl acrylate, polyethyl acrylate, and poly-3-methoxy methyl acrylate.
8. The preparation method of the lithium-supplementing composite isolating membrane according to any one of claims 1 to 7, which is characterized by comprising the following steps:
s1, adding the lithium-rich material and the binder into a solvent, and uniformly mixing to obtain a lithium supplement slurry;
and S2, coating the lithium supplement slurry on one side of the base film facing the positive electrode, and drying at the temperature of 35-110 ℃ to prepare the lithium supplement composite film.
9. The method of claim 8, wherein in step S1, the mixing is performed in an environment with a humidity of less than 1% and a temperature of 20-30 ℃, and the solvent is one selected from N-methylpyrrolidone, dimethylformamide, diethylformamide, dimethylsulfoxide, and tetrahydrofuran.
10. The application of the lithium supplement composite isolating membrane as claimed in any one of claims 1 to 7, wherein the lithium supplement composite isolating membrane is laminated or wound with a positive plate, a negative plate and electrolyte to prepare the lithium ion battery, wherein the lithium supplement composite isolating membrane is positioned between the positive plate and the negative plate, and a lithium supplement layer in the lithium supplement composite isolating membrane faces to one side of the positive plate.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115863913A (en) * | 2022-12-28 | 2023-03-28 | 重庆太蓝新能源有限公司 | Preparation method of lithium-supplement diaphragm, diaphragm and lithium ion battery |
| CN116914371A (en) * | 2023-09-14 | 2023-10-20 | 宁德时代新能源科技股份有限公司 | Separator, preparation method thereof, battery and power utilization device |
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| CN111816822A (en) * | 2020-06-18 | 2020-10-23 | 中国科学院化学研究所 | Functional lithium-supplementing diaphragm and preparation method thereof |
| CN112271405A (en) * | 2020-10-16 | 2021-01-26 | 欣旺达电动汽车电池有限公司 | Lithium-supplementing composite diaphragm and preparation method thereof |
| CN113078417A (en) * | 2021-03-12 | 2021-07-06 | 天津市捷威动力工业有限公司 | Composite lithium-supplementing diaphragm and secondary battery thereof |
| CN113809478A (en) * | 2021-08-26 | 2021-12-17 | 深圳市雄韬电源科技股份有限公司 | Composite diaphragm for directionally supplementing lithium to positive electrode and preparation method thereof |
| CN113851786A (en) * | 2021-06-03 | 2021-12-28 | 中材锂膜有限公司 | Pre-lithiation composite diaphragm and preparation method thereof |
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| CN111816822A (en) * | 2020-06-18 | 2020-10-23 | 中国科学院化学研究所 | Functional lithium-supplementing diaphragm and preparation method thereof |
| CN112271405A (en) * | 2020-10-16 | 2021-01-26 | 欣旺达电动汽车电池有限公司 | Lithium-supplementing composite diaphragm and preparation method thereof |
| CN113078417A (en) * | 2021-03-12 | 2021-07-06 | 天津市捷威动力工业有限公司 | Composite lithium-supplementing diaphragm and secondary battery thereof |
| CN113851786A (en) * | 2021-06-03 | 2021-12-28 | 中材锂膜有限公司 | Pre-lithiation composite diaphragm and preparation method thereof |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115863913A (en) * | 2022-12-28 | 2023-03-28 | 重庆太蓝新能源有限公司 | Preparation method of lithium-supplement diaphragm, diaphragm and lithium ion battery |
| CN115863913B (en) * | 2022-12-28 | 2024-03-22 | 重庆太蓝新能源有限公司 | Preparation method of lithium supplementing diaphragm, diaphragm and lithium ion battery |
| CN116914371A (en) * | 2023-09-14 | 2023-10-20 | 宁德时代新能源科技股份有限公司 | Separator, preparation method thereof, battery and power utilization device |
| CN116914371B (en) * | 2023-09-14 | 2024-02-06 | 宁德时代新能源科技股份有限公司 | Separator, preparation method thereof, battery and power utilization device |
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