Electrolyte with thermal runaway shut-down at high temperature in-situ polymerization and preparation and application thereof

Abstract

This invention provides a thermal runaway-blocking electrolyte with high-temperature in-situ polymerization, its preparation, and its application, belonging to the field of lithium battery technology. The electrolyte comprises a lithium salt, a carbonate solvent, a fluorinated diluent, and a siloxane polymerization precursor; the volume ratio of the fluorinated diluent, the siloxane polymerization precursor, and the carbonate solvent is (0.2~0.6):(0.1~0.5):1; the lithium salt is dissolved in the carbonate solvent to form a first-phase electrolyte, and the concentration of the lithium salt in the first-phase electrolyte is 0.8 mol / L~1.2 mol / L. At high temperatures, this electrolyte can undergo in-situ polymerization initiated by lithiated graphite, transforming the electrolyte from a liquid state to a gel state, thereby blocking direct contact between the positive and negative electrodes of the battery and preventing further thermal runaway reactions.

Description

Technical Field

[0001] This invention relates to the field of lithium battery technology, specifically to a thermal runaway-blocking electrolyte with high-temperature in-situ polymerization, its preparation, and its application. Background Technology

[0002] With the continuous development of lithium-ion batteries, their energy density is also constantly improving. However, while the increased energy density enhances battery performance, it also leads to a higher concentration of energy release, significantly increasing the potential danger in the event of a safety accident. Especially with increased cycle count and usage time, lithium-ion batteries experience varying degrees of aging. Aged lithium-ion batteries are more prone to self-heating and thermal runaway under mechanical, electrical, and thermal abuse, resulting in reduced thermal stability and safety. Lithium metal batteries, as the next generation of high-energy-density batteries, have an energy density far exceeding that of traditional lithium-ion batteries, but also come with higher safety risks. Whether it's a lithium-ion battery or a lithium metal battery, a malfunction or short circuit can lead to overheating, fire, or even explosion, seriously threatening people's lives and property. Therefore, the thermal runaway problem of lithium-ion and lithium metal batteries is a technical issue that urgently needs to be addressed.

[0003] Battery thermal runaway is driven by a series of exothermic reactions that spontaneously increase the temperature of a lithium-ion battery. In chronological order, battery thermal runaway can be divided into three stages: negative electrode / electrolyte reaction, positive electrode / electrolyte reaction, positive / negative electrode reaction, and electrolyte combustion. Among these, the direct contact reaction between the positive and negative electrodes is the key factor triggering the rapid temperature rise in the later stages of battery thermal runaway. Under thermal abuse conditions (especially at temperatures above 140°C), the battery separator shrinks, causing direct contact between the positive and negative electrodes and creating an internal short circuit. This internal short circuit generates and accumulates a large amount of heat in a very short time, leading to a fire or explosion. Therefore, maintaining a robust physical barrier between the negative and positive electrodes under thermal abuse conditions is considered a major challenge in effectively preventing thermal runaway and ensuring the thermal safety of lithium-ion batteries. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a thermal runaway-blocking electrolyte and its preparation method. This electrolyte undergoes in-situ polymerization at high temperatures, transforming from a liquid to a gel state, thereby blocking direct contact between the positive and negative electrodes of the battery and preventing further thermal runaway reactions.

[0005] Specifically, in order to achieve the above objectives, the present invention adopts the following technical solution: An electrolyte comprises a lithium salt, a carbonate solvent, a fluorinated diluent, and a siloxane polymerization precursor; the volume ratio of the fluorinated diluent, the siloxane polymerization precursor, and the carbonate solvent is (0.2~0.6):(0.1~0.5):1; the lithium salt is dissolved in the carbonate solvent to form a first-phase electrolyte, the concentration of the lithium salt in the first-phase electrolyte being 0.8 mol / L~1.2 mol / L; the siloxane polymerization precursor is selected from at least one compound of formulas (IV)~(VI). , , ; Among them, R4~R6 are each independently selected from methyl, ethyl, propyl, phenyl, vinyl, glycidyl, and methoxy; R7~R 12 Each is independently selected from methyl, ethyl, propyl, phenyl, trifluoropropyl, vinyl, glycidyl, cyclohexyl epoxide, and methoxy; n is an integer from 4 to 10.

[0006] In a preferred embodiment, the siloxane polymerization precursor is at least one of hexamethylcyclotrisiloxane, trivinyltrimethylcyclotrisiloxane, octamethylcyclotetrasiloxane, tetravinyltetramethylcyclotetrasiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetra(3,3,3-trifluoropropyl)cyclotetrasiloxane, epoxycyclohexyl-terminated polydimethylsiloxane, and epoxypropyl-terminated dimethylsiloxane.

[0007] In a preferred embodiment, the lithium salt is at least one of lithium hexafluorophosphate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium perchlorate, lithium bis(oxalateborate), and lithium difluorooxalateborate.

[0008] In a preferred embodiment, the fluorinated diluent is selected from 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, 2,2,2-trifluoroethyl ether, fluorobenzene, ethoxy(pentafluoro)cyclotriphosphazene, and tri(2,2,2-trifluoroethyl) phosphate.

[0009] In a preferred embodiment, the carbonate solvent is selected from one or more compounds represented by formulas (I) to (III): , , ; R1 and R2 are each independently selected from methyl, ethyl, propyl, phenyl, benzyl, and haloalkyl; R3 is selected from vinyl, fluorine, chlorine, hydrogen, and methyl.

[0010] In a further preferred embodiment, the carbonate solvent is selected from dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, propyl carbonate, benzyl methyl carbonate, ethylene glycol carbonate, propylene glycol carbonate, vinylene carbonate, fluoroethylene carbonate, and chloroethylene carbonate.

[0011] The preparation method of the electrolyte includes the following steps: S1. Add lithium salt to carbonate solvent and dissolve it completely to obtain the first phase electrolyte; S2. Add a fluorine-containing diluent to the first phase electrolyte and dissolve it completely; S3. Add the siloxane polymerization precursor to the diluted solution obtained in step S2 and dissolve it completely to obtain the electrolyte.

[0012] The present invention also provides a lithium battery, wherein the lithium battery comprises the electrolyte described in any of the above embodiments.

[0013] In a preferred embodiment, the lithium battery further includes a positive electrode and a negative electrode, wherein the positive electrode material is a nickel-cobalt-manganese ternary material, and the negative electrode material is graphite or metallic lithium.

[0014] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: (1) The electrode solution provided by the present invention contains a siloxane polymerization precursor, which can undergo in-situ polymerization reaction under the initiation of lithiated graphite or lithium metal. This electrolyte is used to prepare lithium batteries. In the early stage of battery thermal runaway, when the SEI film is destroyed and active lithium or lithiated graphite is exposed, the siloxane polymerization precursor can undergo anionic ring-opening polymerization or condensation polymerization reaction to form a polysiloxane network passivation film with high thermal stability. This effectively prevents the continuous reaction between the electrolyte and the negative electrode, reduces the heat accumulation caused by exothermic side reactions, and thus inhibits the heat accumulation in the early stage of thermal runaway.

[0015] (2) The electrode solution provided by this invention can complete the in-situ polymerization reaction at 140°C in 0.5 to 2 hours, transforming the electrolyte from a liquid state to a gel state. In the later stages of battery thermal runaway, as the temperature rises to 120°C to 180°C, the siloxane polymerization precursors in the electrolyte can polymerize in-situ under thermal induction to form a three-dimensional cross-linked polysiloxane network, transforming the electrolyte from a liquid state to a gel state. The gel-state electrolyte can prevent the membrane inside the battery from shrinking, prevent direct contact between the positive and negative electrodes, and ultimately avoid the occurrence of large-area short circuits and violent energy release within the battery. This prevents the occurrence of thermal runaway in the later stages and improves battery safety.

[0016] (3) The electrode solution provided by the present invention uses conventional carbonate solvents, which ensures that the battery has good electrochemical performance, improves the safety of the battery without changing the commercial main solvent, and reduces the battery manufacturing cost to the greatest extent. Attached Figure Description

[0017] Figure 1 The images show the appearance of the electrolyte of Example 1 of the present invention after being kept at 140°C for 0.5 h and the electrolyte of Comparative Example 1 after being kept at 140°C for 5 h. Figure 2 The following are cycle specific capacity curves of Ni65|Gra full cells prepared using the electrolytes of Example 1 and Comparative Example 1 of the present invention. Figure 3 The first charge-discharge curves of Ni65|Gra full cells prepared using the electrolytes of Example 1 and Comparative Example 1 of this invention are shown. Figure 4 The differential scanning calorimetry (DSC) heat flow curves of the electrolyte and lithium graphite mixture of Example 1 and Comparative Example 1 of the present invention at 50°C to 350°C are shown. Detailed Implementation

[0018] The following description, in conjunction with embodiments, clearly and completely describes the technical solutions of this application, so that those skilled in the art can fully understand this application. Obviously, the described embodiments are merely some preferred embodiments of this application, and not all embodiments. Any equivalent modifications or substitutions made by those skilled in the art to the following embodiments without creative effort are within the protection scope of this application.

[0019] A specific embodiment of the present invention provides an electrolyte comprising a lithium salt, a carbonate solvent, a fluorinated diluent, and a siloxane polymerization precursor; the volume ratio of the fluorinated diluent, the siloxane polymerization precursor, and the carbonate solvent is (0.2~0.6):(0.1~0.5):1; the lithium salt is dissolved in the carbonate solvent to form a first-phase electrolyte, the concentration of the lithium salt in the first-phase electrolyte being 0.8 mol / L~1.2 mol / L; the siloxane polymerization precursor is selected from at least one compound represented by formulas (IV)~(VI). , , ; Among them, R4~R6 are each independently selected from methyl, ethyl, propyl, phenyl, vinyl, glycidyl, and methoxy; R7~R 12 Each is independently selected from methyl, ethyl, propyl, phenyl, trifluoropropyl, vinyl, glycidyl, cyclohexyl epoxide, and methoxy; n is an integer from 4 to 10.

[0020] Lithium salts are soluble in carbonate solvents but insoluble in fluorinated diluents. The siloxane polymerization precursor is miscible with the fluorinated diluent, forming a single-phase clear solution. In the early stages of thermal runaway, when the solid electrolyte interphase (SEI) is damaged, exposing active lithium or lithiated graphite, the siloxane polymerization precursor can undergo anionic ring-opening polymerization or condensation polymerization to form a polysiloxane passivation layer to repair and passivate the SEI film, preventing the electrolyte from continuously reacting with the negative electrode. In the later stages of thermal runaway, as the temperature rises to 120℃~180℃, the siloxane polymerization precursor in the electrolyte can polymerize in situ under thermal induction to form a three-dimensional cross-linked polysiloxane network, causing the electrolyte to change from a liquid state to a gel state. This prevents direct contact between the positive and negative electrodes, blocking internal short circuits and thus preventing overall battery thermal runaway.

[0021] In some specific embodiments, the volume ratio of the fluorinated diluent, the siloxane polymerization precursor, and the carbonate solvent is 0.2:0.1:1, 0.3:0.4:1, 0.4:0.4:1, 0.5:0.4:1, 0.3:0.3:1, 0.3:0.2:1, or 0.6:0.5:1, but is not limited thereto.

[0022] In some specific embodiments, the concentration of the lithium salt in the first phase electrolyte is 0.8 mol / L, 0.9 mol / L, 1.0 mol / L, 1.1 mol / L, or 1.2 mol / L, but is not limited thereto.

[0023] In some specific embodiments, the siloxane polymerization precursor is at least one of hexamethylcyclotrisiloxane, trivinyltrimethylcyclotrisiloxane, octamethylcyclotetrasiloxane, tetravinyltetramethylcyclotetrasiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetra(3,3,3-trifluoropropyl)cyclotetrasiloxane, epoxycyclohexyl-terminated polydimethylsiloxane, and epoxypropyl-terminated dimethylsiloxane.

[0024] In some specific embodiments, the lithium salt is at least one of lithium hexafluorophosphate (LiPF6), lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium perchlorate (LiClO4), lithium bis(oxalateborate)borate (LiBOB), and lithium difluorooxalateborate (LiDFOB).

[0025] In some specific embodiments, the fluorinated diluent is selected from 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, 2,2,2-trifluoroethyl ether, fluorobenzene, ethoxy(pentafluoro)cyclotriphosphazene, and tri(2,2,2-trifluoroethyl) phosphate.

[0026] In some specific embodiments, the carbonate solvent is selected from one or more compounds represented by formulas (I) to (III): , , ; R1 and R2 are each independently selected from methyl, ethyl, propyl, phenyl, benzyl, and haloalkyl; R3 is selected from vinyl, fluorine, chlorine, hydrogen, and methyl.

[0027] In some further preferred embodiments, the carbonate solvent is selected from dimethyl carbonate (DMC), diethyl carbonate (DEC), methyl ethyl carbonate (EMC), methyl propyl carbonate, benzyl methyl carbonate, ethylene glycol carbonate (EC), propylene glycol carbonate (PC), vinylene carbonate (VC), fluoroethylene carbonate, and chloroethylene carbonate.

[0028] The present invention provides a method for preparing the electrolyte, comprising the following steps: S1. Add lithium salt to carbonate solvent and dissolve it completely to obtain the first phase electrolyte; S2. Add a fluorine-containing diluent to the first phase electrolyte and dissolve it completely; S3. Add the siloxane polymerization precursor to the diluted solution obtained in step S2 and dissolve it completely to obtain the electrolyte.

[0029] A specific embodiment of the present invention also provides a lithium battery, including the electrolyte, a positive electrode, a negative electrode, and a separator. The positive electrode is a nickel-cobalt-manganese ternary material, such as NCM811 or Ni65. The negative electrode is graphite or metallic lithium. The separator is a polypropylene (PP) separator. The electrode core is fabricated using a lamination process, and then placed into an aluminum-plastic film. The battery undergoes top-side sealing, baking, electrolyte injection, and formation processes to produce a pouch battery.

[0030] Examples 1-5 An electrolyte comprises a lithium salt, a carbonate solvent, a fluorinated diluent, and a siloxane polymerization precursor. The lithium salt is lithium hexafluorophosphate (LiPF6); the carbonate solvent is a mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC) in a 1:1 volume ratio; the fluorinated diluent is 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether; and the siloxane polymerization precursor is glycidyl-terminated dimethylsiloxane. The relationship between the lithium salt concentration and the amount of raw materials in the electrolytes of Examples 1-5 is shown in Table 1.

[0031] The preparation method of this electrolyte includes the following steps: S1. Add lithium salt to carbonate solvent and stir thoroughly to dissolve, thus obtaining the first phase electrolyte; S2. Add a fluorine-containing diluent to the first phase electrolyte and stir thoroughly to dissolve; S3. Add the siloxane polymerization precursor to the diluted solution obtained in step S2 and dissolve it completely to obtain the electrolyte.

[0032] Table 1 Relationship between lithium salt concentration and raw material usage in Examples 1-5

[0033] Comparative Example 1 This comparative example provides an electrolyte that differs from Example 1 in that the siloxane polymerization precursor is tetraethyl orthosilicate; and the volume ratio of the fluorinated diluent, the siloxane polymerization precursor, and the carbonate solvent is 0.3:0.4:1. The preparation method of this electrolyte is the same except for the siloxane polymerization precursor in step S3.

[0034] Comparative Example 2 This comparative example provides an electrolyte that differs from Example 1 in that the siloxane polymerization precursor is trimethoxymethylsilane; and the volume ratio of the fluorinated diluent, the siloxane polymerization precursor, and the carbonate solvent is 0.3:0.4:1. The preparation method of this electrolyte is the same except for the siloxane polymerization precursor in step S3.

[0035] Product performance testing 1. Determine the time required for electrode solution polymerization. The electrolytes from Examples 1-5 and Comparative Examples 1-2 were assembled with lithium metal sheets (Li) and graphite anodes (Gra) to form Li|Gra half-cells. The half-cells were cyclically run for 10 cycles at a current density of 0.1C to allow a stable SEI film (solid electrolyte interface film) to form on the graphite anode surface, while simultaneously allowing lithium ions to embed into the graphite to form lithiated graphite. After cycling, the half-cells were disassembled in an argon-filled glove box. The disassembled lithiated graphite was cleaned with dimethyl carbonate to remove residual electrolyte, and then dried in an argon-filled glove box. The dried lithiated graphite was mixed with 2.5 mL of electrolyte and then placed in a sealed oven at 140°C. The time required for electrolyte polymerization (the endpoint of the polymerization reaction being the overall solidification of the electrolyte) was measured, and the results are shown in Table 2.

[0036] Table 2 Time required for electrolyte polymerization

[0037] As can be seen from the data in Table 2, the activity of the siloxane polymerization precursor in the electrolyte prepared by this invention decreases with the increase of the amount of fluorinated diluent in the electrolyte, and the electrolyte requires more time to polymerize at a high temperature of 140℃. Conversely, as the amount of siloxane polymerization precursor in the electrolyte decreases, the electrolyte also requires more time to polymerize at a high temperature of 140℃. The electrolytes of Comparative Examples 1 and 2, after being kept at 140℃ for 5 hours, still did not show overall solidification of the electrode liquid, indicating that neither of the electrolytes in Comparative Examples 1 nor 2 possesses the ability to polymerize and solidify in situ at high temperatures. The solidification effect diagrams of the electrolytes in Example 1 and Comparative Example 1 are shown below. Figure 1 As shown.

[0038] 2. Full battery cycle performance test The electrolytes from Examples 1-5 and Comparative Examples 1 and 2 were assembled with Ni65 ternary cathode material (NiCoMn), graphite anode, and PP (polypropylene) separator to form Ni65|Gra full cells. Their cycle performance was tested, and the results are shown in Table 3. The test conditions were as follows: voltage range of 2.8V~4.25V, positive-to-negative electrode capacity ratio of 1.10, test temperature of 30℃, charging at 0.5C rate, discharging at 1C rate, and 100 cycles. The cycle specific capacity curves and first-cycle charge-discharge curves of the Ni65|Gra full cells prepared with the electrolytes from Examples 1 and Comparative Example 1 are shown below. Figure 2 and Figure 3 As shown.

[0039] Table 3. Cycle performance test results of full cells prepared with electrolytes from the examples and comparative examples.

[0040] From Table 3, Figure 2 , Figure 3 As can be seen, under the same experimental conditions, the full cell prepared with the electrode solution provided by this invention exhibits significantly higher first-cycle discharge specific capacity, coulombic efficiency, and capacity retention than the full cells prepared with the electrolytes of Comparative Examples 1 and 2. This indicates that the fluorinated diluent used in the electrolyte of this invention does not affect the solvation structure of the lithium salt, nor does it negatively impact the electrochemical performance of the electrolyte.

[0041] 3. Electrolyte heat release safety test The electrolytes from Examples 1-5 and Comparative Examples 1-2 were assembled with lithium metal sheets (Li) and graphite anodes (Gra) to form Li|Gra half-cells. The half-cells were cycled at a current density of 0.1C for 3 cycles and discharged to 0.01V to form a stable SEI film on the graphite anode surface, while simultaneously allowing lithium ions to embed into the graphite to form lithiated graphite. After cycling, the half-cells were disassembled in an argon-filled glove box. The disassembled lithiated graphite was cleaned with dimethyl carbonate to remove residual electrolyte, and then dried in an argon-filled glove box to obtain dried lithiated graphite. The lithiated graphite was scraped off the electrode surface inside the glove box, and 3.0 mg of lithiated graphite was weighed and mixed with 4.0 mg of electrolyte. This mixture was placed in a DSC crucible for DSC material safety exothermic testing at temperatures ranging from 50℃ to 350℃. The total exothermic heat of the material is shown in Table 4. The DSC curves of the electrolyte and lithiated graphite mixtures from Examples 1 and Comparative Example 1 are shown in Table 4. Figure 4 As shown.

[0042] Table 4. Heat release of electrolyte-lithium graphite mixtures in the examples and comparative examples

[0043] From Table 4 and Figure 4 As can be seen from the results, under the same experimental conditions, the electrolyte provided by this invention can significantly reduce the heat release of lithium graphite and electrolyte, with Example 1 showing a 35% reduction in heat release compared to Comparative Example 1. This indicates that the electrolyte provided by this invention can significantly improve battery safety at the material level and reduce the risk of battery thermal runaway.

[0044] The embodiments described above are merely preferred embodiments of this application and are not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by anyone skilled in the art. Any simple equivalent changes and modifications made based on the scope of protection claimed in this application and the content of the specification should be included within the scope of protection of this application.

Claims

1. An electrolyte, characterized in that, The electrolyte comprises a lithium salt, a carbonate solvent, a fluorinated diluent, and a siloxane polymerization precursor; the volume ratio of the fluorinated diluent, the siloxane polymerization precursor, and the carbonate solvent is (0.2~0.6):(0.1~0.5):1; the lithium salt is dissolved in the carbonate solvent to form a first-phase electrolyte, and the concentration of the lithium salt in the first-phase electrolyte is 0.8 mol / L~1.2 mol / L; the siloxane polymerization precursor is selected from at least one compound of formulas (IV)~(VI). ， ， ； Among them, R4~R6 are each independently selected from methyl, ethyl, propyl, phenyl, vinyl, glycidyl, and methoxy; R7~R 12 Each is independently selected from methyl, ethyl, propyl, phenyl, trifluoropropyl, vinyl, glycidyl, cyclohexyl epoxide, and methoxy; n is an integer from 4 to 10.

2. The electrolyte according to claim 1, characterized in that, The siloxane polymerization precursor is at least one of hexamethylcyclotrisiloxane, trivinyltrimethylcyclotrisiloxane, octamethylcyclotetrasiloxane, tetravinyltetramethylcyclotetrasiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetra(3,3,3-trifluoropropyl)cyclotetrasiloxane, epoxycyclohexyl-terminated polydimethylsiloxane, and epoxypropyl-terminated dimethylsiloxane.

3. The electrolyte according to claim 1, characterized in that, The lithium salt is at least one of lithium hexafluorophosphate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium perchlorate, lithium bis(oxalateborate), and lithium difluorooxalateborate.

4. The electrolyte according to claim 1, characterized in that, The fluorinated diluent is selected from 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, 2,2,2-trifluoroethyl ether, fluorobenzene, ethoxy(pentafluoro)cyclotriphosphazene, and tri(2,2,2-trifluoroethyl) phosphate.

5. The electrolyte according to claim 1, characterized in that, The carbonate solvent is selected from one or more compounds of formulas (I) to (III): ， ， ； R1 and R2 are each independently selected from methyl, ethyl, propyl, phenyl, benzyl, and haloalkyl; R3 is selected from vinyl, fluorine, chlorine, hydrogen, and methyl.

6. The electrolyte according to claim 5, characterized in that, The carbonate solvents are selected from dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, benzyl methyl carbonate, ethylene glycol carbonate, propylene glycol carbonate, vinylene carbonate, fluoroethylene carbonate, and chloroethylene carbonate.

7. The method for preparing the electrolyte according to any one of claims 1 to 6, characterized in that, Includes the following steps: S1. Add lithium salt to carbonate solvent and dissolve it completely to obtain the first phase electrolyte; S2. Add a fluorine-containing diluent to the first phase electrolyte and dissolve it completely; S3. Add the siloxane polymerization precursor to the diluted solution obtained in step S2 and dissolve it completely to obtain the electrolyte.

8. The use of the electrolyte according to any one of claims 1 to 6 in the preparation of lithium batteries.

9. A lithium battery, characterized in that, Includes the electrolyte as described in any one of claims 1 to 6.

10. The lithium battery according to claim 9, characterized in that, It includes a positive electrode and a negative electrode. The positive electrode material is a nickel-cobalt-manganese ternary material, and the negative electrode material is graphite or metallic lithium.

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