CN113036223A - Ultralow-temperature lithium ion battery electrolyte - Google Patents
Ultralow-temperature lithium ion battery electrolyte Download PDFInfo
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Abstract
The invention discloses an ultralow temperature lithium ion battery electrolyte, which belongs to the technical field of lithium ion batteries and comprises a solvent, lithium salt and an additive. The solvent is a mixed solvent composed of carbonates, ethers and acetates. The lithium salt is a mixed lithium salt consisting of lithium hexafluorophosphate, lithium bifluorosulfonyl imide, lithium difluorophosphate and lithium bistrifluoromethanesulfonyl imide. The additive is a mixed additive consisting of vinylene carbonate, fluoroethylene carbonate, lithium nitrate and dichloromethane. Compared with the conventional electrolyte, the conductivity of the ultralow-temperature electrolyte prepared by the method is improved by over 400 percent, the interface film of the negative electrode of the lithium battery is effectively improved, and the polarization effect is reduced.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to an ultralow-temperature lithium ion battery electrolyte.
Background
The lithium ion battery has the advantages of high working voltage, high specific energy, long cycle life, low self-discharge rate, no memory effect and the like, and is widely applied to various fields. The lithium ion battery still faces many problems in practical application and is greatly influenced by the application environment temperature. At present, the working temperature range of the lithium ion battery is-20-55 ℃, and in an environment of ultralow temperature (lower than-40 ℃), the discharge capacity, the cycle performance, the rate performance and the like of the lithium ion battery are greatly reduced, even a serious lithium precipitation phenomenon occurs, and great potential safety hazards are brought.
Under the condition of low temperature, various performances of the lithium ion battery are severely restricted, which is mainly attributed to that under the condition of ultralow temperature, the viscosity of liquid electrolyte is sharply reduced, the ionic conductivity is remarkably reduced, the interfacial impedance of an electrode and the migration impedance of lithium ions are greatly increased, the electronic rate is not matched with the fast migration of an external circuit, so that the serious polarization inside the lithium ion battery is caused, a large amount of lithium ions are deposited and separated out on the surface of a negative electrode, an SEI film is rapidly thickened, and finally the battery is disabled. In order to expand the application field of lithium ion batteries, it is urgently needed to improve various performances of the lithium ion batteries under the ultralow temperature condition, and the breakthrough of the technology lies in developing ultralow temperature electrolyte.
Patent document CN109742448B relates to a low-temperature electrolyte for a lithium ion battery, which can make the lithium ion battery have very excellent low-temperature performance, and the discharge specific capacity at-40 ℃ reaches at least 60% of the discharge specific capacity at 25 ℃, even can reach 73%, which is significantly better than the existing lithium ion battery prepared from the commercialized low-temperature electrolyte. Meanwhile, the discharge voltage platform of the lithium ion battery at the temperature of-40 ℃ is higher than 3.2V, and can reach 3.5V at most, and is also higher than the voltage platform (lower than 3.2V) of the lithium ion battery prepared by the commercialized low-temperature electrolyte. Compared with the traditional electrolyte, the low-temperature electrolyte disclosed by the document has the advantages of lower raw material cost, simplicity in preparation, more excellent low-temperature performance and wider usable temperature range of the prepared lithium ion battery, so that the low-temperature electrolyte is suitable for being used on various mobile electronic products, electric automobiles and power supply devices in other mobile communication fields and military fields, and is particularly suitable for being used in a low-temperature environment.
Patent document CN105047996B relates to a low-temperature electrolyte for a lithium ion battery and a lithium ion battery, and belongs to the technical field of lithium ion batteries. The low-temperature electrolyte of the lithium ion battery disclosed by the patent document comprises the following components in percentage by weight: 5-20% of lithium hexafluorophosphate, 0.1-3% of lithium fluoride, 0.2-5% of lithium tetrafluoroborate, 48-94.7% of electrolyte solvent, 2-5% of vinylene carbonate, 2-10% of ethyl propionate and 1-5% of ethyl acetate. The lithium ion battery low-temperature electrolyte disclosed in the document can improve the charge and discharge performance and the cycle performance of the electrolyte at low temperature.
Although the solutions disclosed in the above two patent documents improve the low-temperature performance of the battery under general low-temperature environmental conditions, the problem of poor low-temperature performance of the lithium ion battery is still not solved under the ultra-low temperature condition of-60 ℃, and therefore, the development of the lithium ion electrolyte applied under the ultra-low temperature condition is of great significance.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention provides the ultralow temperature lithium ion battery electrolyte, which improves the ionic conductivity of the electrolyte under the ultralow temperature condition, effectively improves a negative electrode interface film and reduces electrode polarization.
An ultralow temperature lithium ion battery electrolyte comprises a solvent, lithium salt and an additive, wherein the solvent is a mixed solvent consisting of carbonates, ethers and acetates; the lithium salt is a mixed lithium salt consisting of lithium hexafluorophosphate, lithium bifluorosulfonyl imide, lithium difluorophosphate and lithium bistrifluoromethanesulfonyl imide; the additive is a mixed additive consisting of vinylene carbonate, fluoroethylene carbonate, lithium nitrate and dichloromethane;
wherein the mass ratio of the solvent, the lithium salt and the additive in the electrolyte is 49.5-78.5%, 17.0-45.9% and 4.5-5.1%, respectively.
The mixed use of the solvent can reduce the viscosity of the electrolyte at low temperature and improve the ionic conductivity of the electrolyte at low temperature; the high-concentration lithium salt can obviously improve the ionic conductivity of the electrolyte under the low-temperature condition; the mixed additive can reduce the diffusion resistance and charge alternation resistance of lithium ions in the SEI film.
The mass ratio of the carbonates, the ethers and the acetates in the solvent is respectively 60.6-80.9%, 6.4-10.3% and 12.7-31.5%.
The carbonate is at least one of ethylene carbonate, ethyl methyl carbonate or propylene carbonate.
The carbonates comprise ethylene carbonate, ethyl methyl carbonate and propylene carbonate, and the mass ratio of the ethylene carbonate, the ethyl methyl carbonate and the propylene carbonate in the carbonates is 15.7-29.9%, 59.7-78.7% and 5.5-10.4%, respectively.
The ether is ethylene glycol dimethyl ether, and the acetate is ethyl acetate.
The mass ratio of lithium hexafluorophosphate, lithium bifluorosulfonyl imide, lithium difluorophosphate and lithium bifluoromethanesulfonyl imide in the lithium salt is 31.3-66.7%, 28.9-62.5%, 2.2-5.9% and 2.2-5.9% respectively.
The concentration of lithium salt in the electrolyte is 1-3 mol/L. More preferably, the concentration of lithium salt in the electrolyte is 2-3 mol/L.
The mass ratio of vinylene carbonate, fluoroethylene carbonate, lithium nitrate and dichloromethane in the additive is 40.0-44.4%, 40.0-44.5%, 10.0-11.1% and 0.0-10.0%.
The preparation process of the electrolyte of the ultralow temperature lithium ion battery is carried out under the protection of atmosphere.
The oxygen content and the water content in the environment are controlled to be below 0.1ppm in the preparation process of the ultralow-temperature lithium ion battery electrolyte, so that the purity of an organic solvent and an electrochemical stability window are ensured, and meanwhile, the low moisture can prevent lithium salt from decomposing to generate hydrofluoric acid, so that the electrolyte is ineffective.
The application temperature range of the lithium ion battery prepared by the ultralow temperature lithium ion battery electrolyte can be widened to-60-55 ℃.
Compared with the prior art, the invention has the following beneficial effects: the electrolyte of the ultralow temperature lithium ion battery provided by the invention has the advantages that the concentration of electrolyte lithium salt is increased, the mixed solvent of carbonates, ethers and acetates is adopted, the viscosity of the electrolyte at low temperature is reduced, the lithium salt and other additives are matched, the dissociation degree of the lithium salt can be increased, a uniform low-resistance solid electrolyte interface film (SEI) is generated on an electrode interface, and the Li is weakened+The binding capacity of the lithium ion battery and the solvent obviously reduces the viscosity of the electrolyte under the ultralow temperature condition and effectively improves the conductivity of the electrolyte, so that various performances of the lithium ion battery are excellent under the ultralow temperature condition.
Drawings
Fig. 1 is a high and low temperature discharge curve of the lithium ion battery prepared in example 8.
Fig. 2 is a rate charge curve of the lithium ion battery prepared in example 8.
Fig. 3 is a cycle curve of the lithium ion battery prepared in example 8 at-20 ℃.
Detailed Description
Example 1
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 50g of ethylene carbonate, 250g of ethyl methyl carbonate, 17.5g of propylene carbonate, 25g of ethylene glycol dimethyl ether and 50g of ethyl acetate, putting the materials into a beaker, stirring for 20min, uniformly mixing, then slowly adding lithium hexafluorophosphate, lithium bifluorosulfonyl imide salt, lithium difluorophosphate and lithium bistrifluoromethanesulfonyl imide salt, stirring for 3h, completely dissolving to form a mixed solution, then respectively adding 10g of vinylene carbonate and 10g of fluoroethylene carbonate into the mixed solution, stirring for 20min, finally adding 2.5g of lithium nitrate, and stirring for 60min to obtain the ultralow-temperature electrolyte with the lithium salt concentration of 1 mol/L.
Example 2
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 50g of ethylene carbonate, 175g of ethyl methyl carbonate, 17.5g of propylene carbonate, 25g of ethylene glycol dimethyl ether and 50g of ethyl acetate, putting the materials into a beaker, stirring for 20min, uniformly mixing, then slowly adding 100g of lithium hexafluorophosphate, 50g of lithium bifluorosulfonyl imide, 5g of lithium difluorophosphate and 5g of lithium bistrifluoromethanesulfonyl imide, stirring for 3h to completely dissolve the materials to form a mixed solution, then respectively adding 10g of vinylene carbonate and 10g of fluoroethylene carbonate into the mixed solution, stirring for 20min, finally adding 2.5g of lithium nitrate, and stirring for 60min to obtain the ultralow-temperature electrolyte with the lithium salt concentration of 2 mol/L.
Example 3
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 50g of ethylene carbonate, 100g of ethyl methyl carbonate, 17.5g of propylene carbonate, 25g of ethylene glycol dimethyl ether and 50g of ethyl acetate, putting the materials into a beaker, stirring for 20min, uniformly mixing, then slowly adding 150g of lithium hexafluorophosphate, 65g of lithium bifluorosulfonyl imide, 5g of lithium difluorophosphate and 5g of lithium bistrifluoromethanesulfonyl imide, stirring for 3h to completely dissolve the materials to form a mixed solution, then respectively adding 10g of vinylene carbonate and 10g of fluoroethylene carbonate into the mixed solution, stirring for 20min, finally adding 2.5g of lithium nitrate, and stirring for 60min to obtain the ultralow temperature electrolyte with the lithium salt concentration of 3 mol/L.
Example 4
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 50g of ethylene carbonate, 175g of ethyl methyl carbonate, 17.5g of propylene carbonate, 25g of ethylene glycol dimethyl ether and 50g of ethyl acetate, putting the materials into a beaker, stirring for 20min, uniformly mixing, then slowly adding a lithium salt consisting of 65g of lithium hexafluorophosphate, 65g of lithium bifluorosulfonyl imide, 5g of lithium difluorophosphate and 5g of lithium bistrifluoromethanesulfonyl imide, stirring for 3h to completely dissolve the materials to form a mixed solution, then respectively adding 10g of vinylene carbonate and 10g of fluoroethylene carbonate into the mixed solution, stirring for 20min, finally adding 2.5g of lithium nitrate, and stirring for 60min to obtain the ultralow-temperature electrolyte with the lithium salt concentration of 2 mol/L.
Example 5
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 50g of ethylene carbonate, 175g of ethyl methyl carbonate, 17.5g of propylene carbonate, 25g of ethylene glycol dimethyl ether and 50g of ethyl acetate, putting the materials into a beaker, stirring for 20min, uniformly mixing, then slowly adding lithium hexafluorophosphate, 100g of lithium bifluorosulfonyl imide, 5g of lithium difluorophosphate and 5g of lithium bistrifluoromethanesulfonyl imide, stirring for 3h to form a lithium salt, completely dissolving to form a mixed solution, then respectively adding 10g of vinylene carbonate and 10g of fluoroethylene carbonate into the mixed solution, stirring for 20min, finally adding 2.5g of lithium nitrate, and stirring for 60min to obtain the ultralow-temperature electrolyte with the lithium salt concentration of 2 mol/L.
Example 6
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 50g of ethylene carbonate, 150g of ethyl methyl carbonate, 17.5g of propylene carbonate, 25g of ethylene glycol dimethyl ether and 65g of ethyl acetate, putting the materials into a beaker, stirring for 20min, uniformly mixing, then slowly adding a lithium salt consisting of 100g of lithium hexafluorophosphate, 50g of lithium bifluorosulfonyl imide, 5g of lithium difluorophosphate and 5g of lithium bistrifluoromethanesulfonyl imide, stirring for 3h, completely dissolving to form a mixed solution, then respectively adding 10g of vinylene carbonate and 10g of fluoroethylene carbonate into the mixed solution, stirring for 20min, finally adding 2.5g of lithium nitrate, and stirring for 60min to obtain the ultralow-temperature electrolyte with the lithium salt concentration of 2 mol/L.
Example 7
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 50g of ethylene carbonate, 125g of ethyl methyl carbonate, 17.5g of propylene carbonate, 25g of ethylene glycol dimethyl ether and 100g of ethyl acetate, putting the materials into a beaker, stirring for 20min, uniformly mixing, then slowly adding a lithium salt consisting of 100g of lithium hexafluorophosphate, 50g of lithium bifluorosulfonyl imide, 5g of lithium difluorophosphate and 5g of lithium bistrifluoromethanesulfonyl imide, stirring for 3h, completely dissolving to form a mixed solution, then respectively adding 10g of vinylene carbonate and 10g of fluoroethylene carbonate into the mixed solution, stirring for 20min, finally adding 2.5g of lithium nitrate, stirring for 60min to obtain a lithium salt with the concentration of 2And (3) ultralow-temperature electrolyte of mol/L.
Example 8
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 50g of ethylene carbonate, 150g of ethyl methyl carbonate, 17.5g of propylene carbonate, 25g of ethylene glycol dimethyl ether and 62.5g of ethyl acetate, putting the materials into a beaker, stirring for 20min, uniformly mixing, then slowly adding a lithium salt consisting of 100g of lithium hexafluorophosphate, 50g of lithium bifluorosulfonyl imide, 5g of lithium difluorophosphate and 5g of lithium bistrifluoromethanesulfonyl imide, stirring for 3h, completely dissolving to form a mixed solution, respectively adding 10g of vinylene carbonate, 10g of fluoroethylene carbonate and 2.5g of dichloromethane into the mixed solution, stirring for 20min, finally adding 2.5g of lithium nitrate, and stirring for 60min to obtain the ultralow-temperature electrolyte with the lithium salt concentration of 2 mol/L.
The ultralow-temperature electrolyte prepared in the embodiment is injected into a 10Ah nickel cobalt lithium manganate composite lithium manganate soft-package battery, the lithium ion battery after being injected with the electrolyte is formed, and the formed lithium ion battery is subjected to high and low temperature test, rate performance test and-20 ℃ cycle performance test respectively. As shown in fig. 1, it can be seen from fig. 1 that the lithium ion battery added with the ultra-low temperature electrolyte can still exert 56% of rated capacity even if discharged under the condition of-60 ℃, and the lithium ion battery using the ultra-low temperature electrolyte has good low temperature resistance; the multiplying power charging curve of the lithium ion battery is shown in fig. 2, and the charging voltage platforms of the lithium ion battery under the multiplying power conditions of 1C, 2C and 3C are similar, which indicates that the lithium ion battery can be applied to quick charging; the cycle curve of the lithium ion battery at-20 ℃ is shown in fig. 3, the lithium ion battery can be cycled for more than 300 times at-20 ℃, which shows that the lithium ion battery can meet the normal requirement at-20 ℃.
Comparative example 1
In a glove box (H) filled with argon2O≤0.1ppm，O2Less than or equal to 0.1 ppm), respectively weighing 125g of ethylene carbonate, 260g of ethyl methyl carbonate and 25g of propylene carbonate, putting the materials into a beaker, stirring for 20min, uniformly mixing, and slowly adding 70g of lithium hexafluorophosphate and 5g of bis (fluorosulfonyl) imideAnd stirring the lithium salt consisting of the lithium salt for 3 hours to completely dissolve the lithium salt to form a mixed solution, adding 10g of vinylene carbonate and 5g of fluoroethylene carbonate into the mixed solution respectively, and stirring for 20 minutes to obtain a conventional electrolyte with the lithium salt concentration of 1.1 mol/L.
Application example 1
The ultralow-temperature electrolyte prepared in examples 1-8 and the conventional electrolyte prepared in comparative example 1 are respectively tested for conductivity, the conductivity test results are shown in table 1, and then the ultralow-temperature electrolyte and the conventional electrolyte are respectively injected into a 10Ah nickel cobalt lithium manganate composite lithium manganate soft-package battery to prepare a plurality of nickel cobalt lithium manganate composite lithium manganate soft-package batteries. The nickel cobalt lithium manganate composite lithium manganate soft package battery mainly comprises a positive electrode, a negative electrode, a diaphragm and electrolyte. Wherein the main material of the positive electrode is a lithium nickel cobalt manganese oxide composite lithium manganate material, and the density of the double surfaces is 150g/m2The rolling thickness is 70 mu m; the main material of the negative electrode is artificial graphite, and the density of the two surfaces of the negative electrode is 72g/m2The rolling thickness is 70 mu m; the diaphragm is a PP/PE/PP three-layer dry diaphragm with the thickness of 25 mu m.
The nickel cobalt lithium manganate composite lithium manganate soft-package battery is subjected to formation and capacity grading, then a high-low temperature discharge test and a-20 ℃ cycle test are carried out, the temperature in the high-low temperature discharge test is 55 ℃, 25 ℃, 20 ℃, 40 ℃ and 60 ℃, and the test results are shown in table 1.
TABLE 1 lithium ion battery Performance test recording sheet
| Examples | Electrolyte electricity at-60 DEG C Conductivity (mS/cm） | Discharge capacity at 25 DEG C Volume (Ah) | 55 ℃ discharge capacity retention Retention (%) | Discharge capacity at-20 ℃ to ensure Retention (%) | Discharge capacity at-40 ℃ to ensure Retention (%) | Discharge capacity at-60 ℃ to ensure Retention (%) | 5C constant current of charging Ratio (%) | Capacity retention of 300 weeks at-20 ℃ cycle Retention (%) |
| 1 | 1.5 | 10.2 | 102.2 | 80.6 | 25.6 | 8.5 | 42.6 | 22.6 |
| 2 | 4.4 | 10.3 | 99.9 | 90.2 | 75.1 | 44.6 | 72.5 | 62.3 |
| 3 | 2.8 | 10.2 | 101.9 | 81.6 | 39.5 | 12.1 | 51.2 | 30.5 |
| 4 | 3.9 | 10.4 | 100.1 | 87.1 | 63.5 | 32.5 | 68.5 | 40.3 |
| 5 | 3.1 | 10.5 | 101.3 | 82.4 | 51.2 | 25.6 | 60.9 | 32.1 |
| 6 | 5.0 | 10.1 | 100 | 91.3 | 80.6 | 50.1 | 78.1 | 70.6 |
| 7 | 4.1 | 10.5 | 100.2 | 88.6 | 70.8 | 35.6 | 70.3 | 55.6 |
| 8 | 5.5 | 10.3 | 99.8 | 93.5 | 89.5 | 55.6 | 83.1 | 81.6 |
| Comparative example 1 | 0.3 | 10.4 | 103.5 | 78.4 | 0 | 0 | 32.1 | 0 |
As can be seen from the data in Table 1, the conductivity of the ultra-low temperature electrolytes prepared in examples 1 to 8 is improved by more than 400% compared with the conductivity of the conventional electrolyte prepared in comparative example 1. The lithium ion battery prepared by the ultralow temperature electrolyte in the embodiments 1-8 can discharge under the conditions of-40 ℃ and-60 ℃, the 5C charging constant current ratio is more than 42.6%, and the capacity retention rate after circulating for 300 weeks under the condition of-20 ℃ is more than 22.6%; the lithium ion battery prepared by the conventional electrolyte in the comparative example 1 can not discharge under the conditions of-40 ℃ and-60 ℃, the 5C charging constant current ratio is only 32.1%, and normal charge and discharge circulation can not be carried out under the conditions of-20 ℃.
The lithium ion battery prepared in example 8 has the best performance, the discharge capacity retention rate is 89.5% under the condition of-40 ℃, the discharge capacity retention rate is 55.6% under the condition of-60 ℃, the 5C charging constant current ratio is 83.1%, and the capacity retention rate is 81.6% under the condition of-20 ℃ and after 300 weeks of cycling.
Claims (7)
1. An ultralow temperature lithium ion battery electrolyte comprises a solvent, lithium salt and an additive, and is characterized in that,
the solvent is a mixed solvent composed of carbonates, ethers and acetates;
the lithium salt is a mixed lithium salt consisting of lithium hexafluorophosphate, lithium bifluorosulfonyl imide, lithium difluorophosphate and lithium bistrifluoromethanesulfonyl imide;
the additive is a mixed additive consisting of vinylene carbonate, fluoroethylene carbonate, lithium nitrate and dichloromethane;
wherein the mass ratio of the solvent, the lithium salt and the additive in the electrolyte is 49.5-78.5%, 17.0-45.9% and 4.5-5.1% respectively,
the mass ratio of lithium hexafluorophosphate, lithium bifluorosulfonyl imide, lithium difluorophosphate and lithium bifluoromethanesulfonyl imide in the lithium salt is 31.3-66.7%, 28.9-62.5%, 2.2-5.9% and 2.2-5.9% respectively,
the concentration of lithium salt in the electrolyte is 2-3 mol/L.
2. The ultra-low temperature lithium ion battery electrolyte as claimed in claim 1, wherein the mass ratio of the carbonates, ethers and acetates in the solvent is 60.6-80.9%, 6.4-10.3% and 12.7-31.5%, respectively.
3. The ultra-low temperature lithium ion battery electrolyte of claim 2, wherein the carbonate is at least one of ethylene carbonate, ethyl methyl carbonate or propylene carbonate.
4. The ultra-low temperature lithium ion battery electrolyte as claimed in claim 3, wherein the carbonates comprise ethylene carbonate, ethyl methyl carbonate and propylene carbonate, and the mass ratio of the ethylene carbonate, the ethyl methyl carbonate and the propylene carbonate in the carbonates is 15.7% -29.9%, 59.7% -78.7% and 5.5% -10.4%, respectively.
5. The electrolyte of the ultra-low temperature lithium ion battery as claimed in claim 1, wherein the ether is ethylene glycol dimethyl ether, and the acetate is ethyl acetate.
6. The ultra-low temperature lithium ion battery electrolyte as claimed in claim 1, wherein the mass ratio of vinylene carbonate, fluoroethylene carbonate, lithium nitrate and dichloromethane in the additive is 40.0-44.4%, 40.0-44.5%, 10.0-11.1% and 0.0-10.0%.
7. The ultra-low temperature lithium ion battery electrolyte of claim 1 wherein the formulation process is carried out under atmospheric protection.
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| CN202110588158.5A Active CN113036223B (en) | 2021-05-28 | 2021-05-28 | Ultralow-temperature lithium ion battery electrolyte |
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| CN113659203A (en) * | 2021-07-18 | 2021-11-16 | 哈尔滨工业大学 | Electrolyte containing composite additive and application thereof |
| CN114552000A (en) * | 2022-02-15 | 2022-05-27 | 北京航空航天大学 | Ultralow-temperature graphite-based lithium ion battery and preparation method of electrolyte thereof |
| CN116259846A (en) * | 2023-04-11 | 2023-06-13 | 湖北亿纬动力有限公司 | Lithium ion battery electrolyte and lithium ion battery |
| WO2023198004A1 (en) * | 2022-04-11 | 2023-10-19 | 北京车和家汽车科技有限公司 | Battery electrolyte, and lithium ion battery comprising same |
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| CN107154510A (en) * | 2017-04-06 | 2017-09-12 | 深圳清华大学研究院 | Lithium-ion battery electrolytes and lithium ion battery |
| CN109509912A (en) * | 2017-09-15 | 2019-03-22 | 浙江省化工研究院有限公司 | A method of inhibiting metal lithium dendrite growth |
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| KR20010068820A (en) * | 2000-01-10 | 2001-07-23 | 성재갑 | New electrolytes and lithium ion battery using the same |
| CN107154510A (en) * | 2017-04-06 | 2017-09-12 | 深圳清华大学研究院 | Lithium-ion battery electrolytes and lithium ion battery |
| CN109509912A (en) * | 2017-09-15 | 2019-03-22 | 浙江省化工研究院有限公司 | A method of inhibiting metal lithium dendrite growth |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113659203A (en) * | 2021-07-18 | 2021-11-16 | 哈尔滨工业大学 | Electrolyte containing composite additive and application thereof |
| CN114552000A (en) * | 2022-02-15 | 2022-05-27 | 北京航空航天大学 | Ultralow-temperature graphite-based lithium ion battery and preparation method of electrolyte thereof |
| WO2023198004A1 (en) * | 2022-04-11 | 2023-10-19 | 北京车和家汽车科技有限公司 | Battery electrolyte, and lithium ion battery comprising same |
| CN116259846A (en) * | 2023-04-11 | 2023-06-13 | 湖北亿纬动力有限公司 | Lithium ion battery electrolyte and lithium ion battery |
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| CN113036223B (en) | 2021-10-15 |
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