Battery cell, battery apparatus and electrical apparatus

Abstract

The present application provides a battery cell, a battery apparatus and an electrical apparatus. The battery cell of the present application comprises an electrode assembly, the electrode assembly comprising a positive electrode sheet, a negative electrode sheet and a non-aqueous electrolyte; the positive electrode sheet comprises a positive electrode current collector and a positive electrode active layer arranged thereon, the positive electrode active layer comprising a positive electrode lithium supplementing material; the non-aqueous electrolyte comprises an electrolyte additive represented by formula (I). The energy density, cycle performance and high-temperature storage performance of the battery of the present application are simultaneously improved.

Description

A battery cell, a battery device, and an electrical device.

[0001] This application is based on and claims priority to Chinese Patent Application No. 202411040793.X, filed on July 31, 2024, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] This application relates to the field of battery technology, and in particular to a battery cell, a battery device, and an electrical device. Background Technology

[0003] In recent years, with the increasingly wide range of applications, batteries have been widely used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, as well as in power tools, electric bicycles, electric motorcycles, electric cars, military equipment, aerospace, and many other fields. Due to the significant advancements in battery technology, higher requirements have been placed on their energy density, cycle performance, and storage capacity. Summary of the Invention

[0004] This application was made in view of the above-mentioned problems, and its purpose is to provide a battery cell, a battery device, and an electrical device. This application also improves the energy density, cycle performance, and high-temperature storage performance of the battery.

[0005] To achieve the above objectives, a first aspect of this application provides a battery cell, the battery cell including an electrode assembly, the electrode assembly including a positive electrode sheet, a negative electrode sheet and a non-aqueous electrolyte, the positive electrode sheet including a positive current collector and a positive active layer disposed on the positive current collector, the positive active layer including a positive lithium supplementation material, and the non-aqueous electrolyte including an electrolyte additive shown in formula (I).

[0006] Among them, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following: a group having the structure shown in formula (II), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, wherein n1 and n2 are each independently any integer from 0 to 2; or, when n1 is 1 or 2, R 1 Or R 2 、and R 1 Or R 2 The connected ring carbon atoms and adjacent ring carbon atoms form the structure shown in formula (III);

[0007] Equation (II) is

[0008] Equation (III) is

[0009] R 5 R 6 R 7 and R 8 Each is independently selected from any one of hydrogen atom, halogen atom, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C2-C6 alkenyl, C2-C6 ester, cyano and sulfonic acid groups; n3 and n4 are each independently any integer from 0 to 2.

[0010] Therefore, this application improves lithium replenishment by preferentially oxidizing the electrolyte additive at the positive electrode to form a low-impedance positive electrode CEI interface film. Simultaneously, the electrolyte additive can suppress the formation of R+ (e.g., H+) in the electrolyte. + This reduces damage to the SEI interface film of the negative electrode, reduces lithium consumption, and thus improves the energy density, cycle performance and high-temperature storage performance of the battery.

[0011] In any implementation, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following groups having the structure shown in Formula (II): a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group, and n1 and n2 are each independently any integer from 0 to 2.

[0012] In any implementation, R 1 R 2 R 3 R 4 It is also a hydrogen atom;

[0013] Or, R 1 and R 2 Not simultaneously hydrogen atoms and R 3 and R 4 They are not both hydrogen atoms;

[0014] Or, R 1 R 2 R 3 R 4 R 5 and R 6 The following conditions must be met:

[0015] R 1and R 2 Both are hydrogen atoms and R 3 and R 4 One is a hydrogen atom and the other is any one of the following: a group having the structure shown in general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group, and R in the group having the structure shown in general formula (II) 5 and R 6 They are not both hydrogen atoms;

[0016] Or, R 1 R 2 R 3 R 4 R 5 and R 6 The following conditions must be met:

[0017] R 3 and R 4 Both are hydrogen atoms and R 1 and R 2 One is a hydrogen atom and the other is any one of the following: a group having the structure shown in general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group, and R in the group having the structure shown in general formula (II) 5 and R 6 They are not both hydrogen atoms;

[0018] Or, R 1 R 2 R 3 R 4 R 5 and R 6 The following conditions must be met:

[0019] R 1 and R 2 Both are hydrogen atoms and R 3 and R 4 One is a hydrogen atom and the other is any one of the following: a group having the structure shown in general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, and R in the group having the structure shown in general formula (II) 5 and R 6 Not simultaneously composed of hydrogen atoms or both being hydrogen atoms;

[0020] Or, R 1R 2 R 3 R 4 R 5 and R 6 The following conditions must be met:

[0021] R 3 and R 4 Both are hydrogen atoms and R 1 and R 2 One is a hydrogen atom and the other is any one of the following: a group having the structure shown in general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, and R in the group having the structure shown in general formula (II) 5 and R 6 Not simultaneously composed of hydrogen atoms or both being hydrogen atoms;

[0022] Or, R 1 R 2 R 3 and R 4 The following conditions must be met:

[0023] R 3 and R 4 Both are hydrogen atoms and R 1 and R 2 One is a hydrogen atom, the other and the attached ring carbon atom and adjacent ring carbon atom form the structure shown in formula (III), and the group in the structure shown in formula (III) contains R. 7 and R 8 They are not both hydrogen atoms at the same time or both hydrogen atoms.

[0024] In any embodiment, the electrolyte additive has the structure shown in general formula (I-1).

[0025] Among them, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, where n1 is any integer from 0 to 2; or, when n1 is 1 or 2, R 1 Or R 2 、and R 1 Or R 2The connected ring carbon atoms and adjacent ring carbon atoms form the structure shown in formula (III-1);

[0026] Equation (II-1) is

[0027] Equation (III-1) is

[0028] R 5 R 6 R 7 and R 8 Each group is independently selected from any one of the following: hydrogen atom, halogen atom, C1-C6 alkyl group, C1-C6 haloalkyl group, C1-C6 alkoxy group, C1-C6 haloalkoxy group, C2-C6 alkenyl group, C2-C6 ester group, cyano group, and sulfonic acid group.

[0029] In any embodiment, the electrolyte additive has the structure shown in formula (I-2).

[0030] Among them, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following groups having the structure shown in formula (Ⅱ-1): hydrogen atom, halogen atom, C1-C6 alkyl group, C1-C6 haloalkyl group, C1-C6 alkoxy group, C1-C6 haloalkoxy group, C2-C6 alkenyl group, C2-C6 ester group, cyano group, and sulfonic acid group.

[0031] General formula (II-1) is

[0032] R 5 and R 6 Each group is independently selected from any one of the following: hydrogen atom, halogen atom, C1-C6 alkyl group, C1-C6 haloalkyl group, C1-C6 alkoxy group, C1-C6 haloalkoxy group, C2-C6 alkenyl group, C2-C6 ester group, cyano group, and sulfonic acid group.

[0033] In any implementation, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C1-C3 haloalkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group; or, when n1 is 1 or 2, R 1 Or R 2、and R 1 Or R 2 The connected ring carbon atoms and adjacent ring carbon atoms form a group with the structure shown in formula (III-1); and R 5 R 6 R 7 and R 8 Each group is independently selected from any one of the following: hydrogen atom, halogen atom, C1-C3 alkyl group, C1-C3 haloalkyl group, C1-C3 alkoxy group, C1-C3 haloalkoxy group, C2-C3 alkenyl group, C1-C3 ester group, cyano group, and sulfonic acid group.

[0034] In any implementation, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group, and a hydroxyl group; or, when n1 is 1 or 2, R 1 Or R 2 、and R 1 Or R 2 The connected ring carbon atoms and adjacent ring carbon atoms form a group with the structure shown in formula (III-1); and R 5 R 6 R 7 and R 8 Each is independently selected from any one of hydrogen atoms, halogen atoms, and C1-C3 alkyl groups.

[0035] In any implementation, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C1-C3 haloalkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group, and a sulfonic acid group; and R 5 and R 6 Each group is independently selected from any one of the following: hydrogen atom, halogen atom, C1-C3 alkyl group, C1-C3 haloalkyl group, C1-C3 alkoxy group, C1-C3 haloalkoxy group, C2-C3 alkenyl group, C1-C3 ester group, cyano group, and sulfonic acid group.

[0036] In any implementation, R 1 R 2 R 3and R 4 Each is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, or a C1-C3 haloalkyl group; and R 5 and R 6 Each is independently selected from any one of hydrogen atoms, halogen atoms, C1-C3 alkyl groups, and C1-C3 haloalkyl groups.

[0037] In any implementation, R 1 R 2 R 3 and R 4 Each is independently selected from any one of the groups, hydrogen atoms, F atoms, Cl atoms, Br atoms, methyl, ethyl, propyl, and isopropyl groups having the structure shown in formula (Ⅱ-1); and R 5 and R 6 Each atom is independently selected from any one of hydrogen, F, Cl, Br, methyl, ethyl, propyl, and isopropyl.

[0038] In any embodiment, the groups in the structure shown in formula (Ⅱ-1) are selected from any one of the following groups: Where X is an F atom, a Cl atom, or a Br atom.

[0039] In any implementation, R 1 R 2 R 3 and R 4 Each independently selected X is any one of hydrogen atom, F atom, methyl, ethyl, propyl, monofluoromethyl, trifluoromethyl, cyano, methoxy, ethoxy, hydroxy, vinyl, and methoxyformyl, where X is an F atom; or, when n1 is 1, R 1 Or R 2 、and R 1 Or R 2 The connected ring carbon atoms and the adjacent ring carbon atoms form Group.

[0040] In any implementation, R 1 R 2 R 3 and R 4 Each independently selected X is any one of hydrogen atom, F atom, Cl atom, Br atom, methyl, ethyl, propyl and isopropyl, where X is an F atom.

[0041] In any implementation, R 1 R 2 R 3 and R 4 Each independently selected Any one of hydrogen atom, methyl, and ethyl, where X is an F atom.

[0042] In any embodiment, the electrolyte additive is selected from any one or more of the following compounds:

[0043] In any embodiment, the positive electrode lithium replenishment material includes Li2C. x O y , where x is any integer in the range of 1-4, y is any integer in the range of 3-6, and x+y=2m, where m is any integer in the range of 2-5.

[0044] In any embodiment, the positive electrode lithium replenishment material includes one or more of Li2C2O4, Li2CO3, Li2C4O4, Li2C3O5, and Li2C4O6.

[0045] In any embodiment, the mass percentage of the positive electrode lithium replenishment material in the positive electrode active layer is 0.05%-10%, 0.1%-8%, or 0.1%-5%.

[0046] Therefore, using cathode lithium replenishment materials within the above-mentioned mass ratio range is beneficial to further improve the energy density, cycle performance, and high-temperature storage performance of the battery.

[0047] In any embodiment, the electrolyte additive accounts for 0.01%-20%, 0.1%-10%, or 0.5%-5% of the mass of the electrolyte.

[0048] Therefore, using electrolyte additives within the above-mentioned mass ratio range is beneficial to improving the energy density of the battery, as well as its cycle performance and high-temperature storage performance.

[0049] In any embodiment, the mass percentage of the positive electrode lithium replenishment material in the positive electrode active layer is W1, the mass percentage of the electrolyte additive in the non-aqueous electrolyte is W2, and W1 / W2 is 0.05–20 or 0.1–5.

[0050] In any embodiment, the positive electrode active layer further includes a positive electrode active material, wherein the ratio of the Dv50 particle size of the positive electrode lithium replenishment material to the Dv50 particle size of the positive electrode active material is 1-10 or 5-10.

[0051] Therefore, the combined use of cathode lithium supplementation materials and cathode active materials with the above-mentioned particle size ratio can further improve the energy density of the battery, as well as improve the battery's cycle performance and high-temperature storage performance.

[0052] In any embodiment, the positive electrode active layer further includes a positive electrode active material.

[0053] The positive electrode active material includes one or more of lithium-containing phosphates and lithium-containing transition metal oxides; or...

[0054] The positive electrode active material includes one or more of the following: lithium iron phosphate, lithium manganese iron phosphate, lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and compounds obtained by adding other transition metals or non-transition metals to the aforementioned compounds.

[0055] A second aspect of this application also provides a battery device including the battery cell described in the first aspect of this application, wherein the battery device is a battery module, a battery pack, or an energy storage device.

[0056] A third aspect of this application also provides an electrical device, including a single battery cell as described in the first aspect of this application or a battery device as described in the second aspect of this application. Attached Figure Description

[0057] Figure 1 is a schematic diagram of a battery cell according to one embodiment of this application.

[0058] Figure 2 is an exploded view of a battery cell according to an embodiment of this application shown in Figure 1.

[0059] Figure 3 is a schematic diagram of a battery module according to one embodiment of this application.

[0060] Figure 4 is a schematic diagram of a battery pack according to one embodiment of this application.

[0061] Figure 5 is an exploded view of the battery pack of one embodiment of this application shown in Figure 4.

[0062] Figure 6 is a schematic diagram of an electrical device in which a single battery cell is used as a power source according to an embodiment of this application.

[0063] Explanation of reference numerals in the attached diagram: 1 Battery pack; 2 Upper housing; 3 Lower housing; 4 Battery module; 5 Battery cell; 51 Housing; 52 Electrode assembly; 53 Top cover assembly. Detailed Implementation

[0064] The following detailed description, with appropriate reference to the accompanying drawings, discloses embodiments of the negative electrode active material and its manufacturing method, positive electrode sheet, negative electrode sheet, battery cell, battery module, battery pack, and power supply device of this application. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repetitive descriptions of practically identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided for the purpose of enabling those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0065] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of a particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, it is expected that ranges of 60-110 and 80-120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In this application, unless otherwise stated, the numerical range "ab" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" have been listed in this article; "0-5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is stated as an integer ≥2, it is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0066] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions.

[0067] Unless otherwise specified, all technical features and optional technical features of this application may be combined to form new technical solutions.

[0068] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0069] Unless otherwise specified, in this application, the term "halogen" refers to an atom of a Group VIIA element, including fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), etc.

[0070] Unless otherwise specified, in this application, the term "C1-C6 alkyl" refers to a straight-chain or branched alkyl group containing 1 to 6 carbon atoms, specifically including C1-C3 alkyl and C2-C4 alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, or n-hexyl.

[0071] Unless otherwise specified, in this application, the term "C1-C6 haloalkyl" refers to a C1-C6 alkyl group in which one or more H atoms are substituted with a halogen, wherein the definitions of "C1-C6 alkyl" and "halogen" are as described above. Specifically, this includes C1-C3 haloalkyl and C2-C4 haloalkyl, such as monofluoromethyl, difluoromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, etc.

[0072] Unless otherwise specified, in this application, the term "C1-C6 alkoxy" refers to a C1-C6 alkyl-O- group, wherein "C1-C6 alkyl" is as described above. Non-limiting examples of suitable C1-C6 alkoxy groups include methoxy, ethoxy, and isopropoxy groups.

[0073] Unless otherwise specified, in this application, the term "C1-C6 haloalkoxy" refers to a C1-C6 alkoxy group in which one or more H atoms are substituted by a halogen, wherein the definitions of "C1-C6 alkoxy" and "halogen" are as described above. Specifically, this includes C1-C3 haloalkoxy and C2-C4 haloalkoxy groups, such as difluoromethoxy, trifluoromethoxy, and 2,2,2-trifluoroethoxy.

[0074] Unless otherwise specified, in this application, the term "C2-C6 alkenyl" refers to a straight-chain or branched monovalent hydrocarbon group containing 2 to 6 carbon atoms and having at least one unsaturated carbon-carbon double bond, specifically including C2-C5 alkenyl and C2-C4 alkenyl, such as ethylene, propylene, n-butene, isobutene, n-pentene, isopentene, etc.

[0075] Unless otherwise specified, in this application, the term "C2-C6 ester group" refers to -COO-C1-C6 alkyl, wherein "C1-C6 alkyl" is as described above. Specifically, it includes C2-C5 ester groups and C2-C4 ester groups, such as -COOCH3, -COOCH2CH3, etc.

[0076] [Battery cell]

[0077] A battery cell, also known as a rechargeable battery or storage battery, is a battery that can be recharged after being discharged to activate the active materials and continue to be used.

[0078] Typically, a battery cell includes a positive electrode, a negative electrode, a separator, and an electrolyte. During charging and discharging, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, primarily prevents short circuits while allowing active ions to pass through. The electrolyte, also positioned between the positive and negative electrodes, mainly serves to conduct active ions.

[0079] One embodiment of this application provides a battery cell, the battery cell including an electrode assembly, the electrode assembly including a positive electrode sheet, a negative electrode sheet and a non-aqueous electrolyte, the positive electrode sheet including a positive current collector and a positive active layer disposed on the positive current collector, the positive active layer including a positive lithium supplementing material, and the non-aqueous electrolyte including an electrolyte additive shown in formula (I);

[0080] Among them, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following: a group having the structure shown in formula (II), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, wherein n1 and n2 are each independently any integer from 0 to 2; or, when n1 is 1 or 2, R 1 Or R 2 、and R 1 Or R 2 The connected ring carbon atoms and adjacent ring carbon atoms form the structure shown in formula (III);

[0081] Equation (II) is

[0082] Equation (III) is

[0083] R5 R 6 R 7 and R 8 Each is independently selected from any one of hydrogen atom, halogen atom, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C2-C6 alkenyl, C2-C6 ester, cyano and sulfonic acid groups; n3 and n4 are each independently any integer from 0 to 2.

[0084] Although the mechanism is not yet clear, the applicant unexpectedly discovered that by preferentially oxidizing the electrolyte additive at the positive electrode to form a low-impedance positive electrode CEI interface film, the lithium replenishment effect is improved. At the same time, the electrolyte additive can inhibit the generation of R+ (e.g., H+) in the electrolyte. + This reduces damage to the SEI interface film of the negative electrode, reduces lithium consumption, and thus improves the energy density, cycle performance and high-temperature storage performance of the battery.

[0085] In some implementations, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following groups having the structure shown in formula (II): hydrogen atom, halogen atom, C1-C6 alkyl group, C1-C6 haloalkyl group, C1-C6 alkoxy group, C1-C6 haloalkoxy group, C2-C6 alkenyl group, C2-C6 ester group, cyano group, and sulfonic acid group, and n1 and n2 are each independently any integer from 0 to 2 (e.g., 0, 1, or 2).

[0086] In some implementations, R 1 R 2 R 3 R 4 It is also a hydrogen atom;

[0087] Or, R 1 and R 2 Not simultaneously hydrogen atoms and R 3 and R 4 They are not both hydrogen atoms;

[0088] Or, R 1 R 2 R 3 R 4 R 5 and R 6 The following conditions must be met:

[0089] R 1 and R 2 Both are hydrogen atoms and R 3 and R 4One is a hydrogen atom and the other is any one of the following: a group having the structure shown in general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group, and R in the group having the structure shown in general formula (II) 5 and R 6 They are not both hydrogen atoms;

[0090] Or, R 1 R 2 R 3 R 4 R 5 and R 6 The following conditions must be met:

[0091] R 3 and R 4 Both are hydrogen atoms and R 1 and R 2 One is a hydrogen atom and the other is any one of the following: a group having the structure shown in general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group, and R in the group having the structure shown in general formula (II) 5 and R 6 They are not both hydrogen atoms;

[0092] Or, R 1 R 2 R 3 R 4 R 5 and R 6 The following conditions must be met:

[0093] R 1 and R 2 Both are hydrogen atoms and R 3 and R 4 One is a hydrogen atom and the other is any one of the following: a group having the structure shown in general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, and R in the group having the structure shown in general formula (II) 5 and R 6 Not simultaneously composed of hydrogen atoms or both being hydrogen atoms;

[0094] Or, R 1 R 2 R 3 R 4 R5 and R 6 The following conditions must be met:

[0095] R 3 and R 4 Both are hydrogen atoms and R 1 and R 2 One is a hydrogen atom and the other is any one of the following: a group having the structure shown in general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, and R in the group having the structure shown in general formula (II) 5 and R 6 Not simultaneously composed of hydrogen atoms or both being hydrogen atoms;

[0096] Or, R 1 R 2 R 3 and R 4 The following conditions must be met:

[0097] R 3 and R 4 Both are hydrogen atoms and R 1 and R 2 One is a hydrogen atom, the other and the attached ring carbon atom and adjacent ring carbon atom form the structure shown in formula (III), and the group in the structure shown in formula (III) contains R. 7 and R 8 They are not both hydrogen atoms at the same time or both hydrogen atoms.

[0098] In some embodiments, the electrolyte additive has the structure shown in general formula (I-1).

[0099] Among them, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following having the structure shown in formula (II-1): a group, a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, where n1 is any integer from 0 to 2 (e.g., 0, 1, or 2); or, when n1 is 1 or 2, R 1 Or R 2 、and R 1 Or R 2 The connected ring carbon atoms and adjacent ring carbon atoms form the structure shown in formula (III-1);

[0100] Equation (II-1) is

[0101] Equation (III-1) is

[0102] R 5 R 6 R 7 and R 8 Each group is independently selected from any one of the following: hydrogen atom, halogen atom, C1-C6 alkyl group, C1-C6 haloalkyl group, C1-C6 alkoxy group, C1-C6 haloalkoxy group, C2-C6 alkenyl group, C2-C6 ester group, cyano group, and sulfonic acid group.

[0103] In some embodiments, the electrolyte additive has the structure shown in formula (I-2).

[0104] Among them, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following groups having the structure shown in formula (Ⅱ-1): hydrogen atom, halogen atom, C1-C6 alkyl group, C1-C6 haloalkyl group, C1-C6 alkoxy group, C1-C6 haloalkoxy group, C2-C6 alkenyl group, C2-C6 ester group, cyano group, and sulfonic acid group.

[0105] General formula (II-1) is

[0106] R 5 and R 6 Each group is independently selected from any one of the following: hydrogen atom, halogen atom, C1-C6 alkyl group, C1-C6 haloalkyl group, C1-C6 alkoxy group, C1-C6 haloalkoxy group, C2-C6 alkenyl group, C2-C6 ester group, cyano group, and sulfonic acid group.

[0107] The cyclic sulfate rings in the above general formula (I-2) are all five-membered rings, which can form a denser SEI film. Compared with six-membered rings, they have greater ring strain and are easier to form films on the negative electrode.

[0108] In some implementations, R 1 R 2 R 3 and R 4Each group is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C1-C3 haloalkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group; or, when n1 is 1 or 2, R 1 Or R 2 、and R 1 Or R 2 The connected ring carbon atoms and adjacent ring carbon atoms form a group with the structure shown in formula (III-1); and R 5 R 6 R 7 and R 8 Each group is independently selected from any one of the following: hydrogen atom, halogen atom, C1-C3 alkyl group, C1-C3 haloalkyl group, C1-C3 alkoxy group, C1-C3 haloalkoxy group, C2-C3 alkenyl group, C1-C3 ester group, cyano group, and sulfonic acid group.

[0109] In some implementations, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group, and a hydroxyl group; or, when n1 is 1 or 2, R 1 Or R 2 、and R 1 Or R 2 The connected ring carbon atoms and adjacent ring carbon atoms form a group with the structure shown in formula (III-1); and R 5 R 6 R 7 and R 8 Each is independently selected from any one of hydrogen atoms, halogen atoms, and C1-C3 alkyl groups.

[0110] In some implementations, R 1 R 2 R 3 and R 4 Each group is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C1-C3 haloalkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group, and a sulfonic acid group; and R 5 and R 6Each group is independently selected from any one of the following: hydrogen atom, halogen atom, C1-C3 alkyl group, C1-C3 haloalkyl group, C1-C3 alkoxy group, C1-C3 haloalkoxy group, C2-C3 alkenyl group, C1-C3 ester group, cyano group, and sulfonic acid group.

[0111] In some implementations, R 1 R 2 R 3 and R 4 Each is independently selected from any one of the following: a group having the structure shown in formula (Ⅱ-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, or a C1-C3 haloalkyl group; and R 5 and R 6 Each is independently selected from any one of hydrogen atoms, halogen atoms, C1-C3 alkyl groups, and C1-C3 haloalkyl groups.

[0112] In some implementations, R 1 R 2 R 3 and R 4 Each is independently selected from any one of the groups, hydrogen atoms, F atoms, Cl atoms, Br atoms, methyl, ethyl, propyl, and isopropyl groups having the structure shown in formula (Ⅱ-1); and R 5 and R 6 Each atom is independently selected from any one of hydrogen, F, Cl, Br, methyl, ethyl, propyl, and isopropyl.

[0113] In some embodiments, the groups in the structure shown in formula (Ⅱ-1) are selected from any one of the following groups: Where X is an F atom, a Cl atom, or a Br atom.

[0114] In some implementations, R 1 R 2 R 3 and R 4 Each independently selected X is any one of hydrogen atom, F atom, methyl, ethyl, propyl, monofluoromethyl, trifluoromethyl, cyano, methoxy, ethoxy, hydroxy, vinyl, and methoxyformyl, where X is an F atom; or, when n1 is 1, R 1 Or R 2 、and R 1 Or R 2 The connected ring carbon atoms and the adjacent ring carbon atoms form Group.

[0115] In some implementations, R 1R 2 R 3 and R 4 Each independently selected X is any one of hydrogen atom, F atom, Cl atom, Br atom, methyl, ethyl, propyl and isopropyl, where X is an F atom.

[0116] In some implementations, R 1 R 2 R 3 and R 4 Each independently selected Any one of hydrogen atom, methyl, and ethyl, where X is an F atom.

[0117] In some embodiments, the electrolyte additive is selected from any one or more of the following compounds:

[0118] In some embodiments, the positive electrode lithium replenishment material includes Li2C. x O y , where x is any integer in the range of 1-4 (e.g., 1, 2, 3, 4 or any range of the above values), y is any integer in the range of 3-6 (e.g., 3, 4, 5, 6 or any range of the above values), and x+y=2m, where m is any integer in the range of 2-5 (e.g., 2, 3, 4, 5 or any range of the above values).

[0119] In some embodiments, the positive electrode lithium replenishment material includes one or more of Li2C2O4, Li2CO3, Li2C4O4, Li2C3O5, and Li2C4O6.

[0120] In some embodiments, the mass percentage of the positive electrode lithium replenishment material in the positive electrode active layer is 0.05%-10%, 0.1%-8%, or 0.1%-5%, for example, 0.05%, 0.08%, 0.1%, 0.5%, 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or any range of the above values.

[0121] Therefore, using cathode lithium replenishment materials within the above-mentioned mass ratio range is beneficial to further improve the energy density, cycle performance, and high-temperature storage performance of the battery.

[0122] In some embodiments, the electrolyte additive in the non-aqueous electrolyte has a mass percentage of 0.01%-20%, 0.1%-10%, or 0.5%-5%, for example, 0.01%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 8%, 10%, 12%, 15%, 17%, 20%, or any range of the above values.

[0123] Therefore, using electrolyte additives within the above-mentioned mass percentage range is beneficial to improving the energy density of battery devices and enhancing their cycle performance and high-temperature storage performance.

[0124] In some embodiments, the mass percentage of the positive electrode lithium replenishment material in the positive electrode active layer is W1, the mass percentage of the electrolyte additive in the non-aqueous electrolyte is W2, and W1 / W2 is 0.05-20 or 0.1-5, for example, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.8, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 17, 20 or any range of the above values.

[0125] In some embodiments, the positive electrode active layer further includes a positive electrode active material, wherein the ratio of the Dv50 particle size of the positive electrode lithium replenishment material to the Dv50 particle size of the positive electrode active material is 1-10 or 5-10, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or any range of the above values.

[0126] Therefore, the combined use of cathode lithium supplementation materials and cathode active materials with the above-mentioned particle size ratio can further improve the energy density of the battery, as well as improve the battery's cycle performance and high-temperature storage performance.

[0127] In this application, the Dv50 particle size of the cathode lithium replenishment material and the cathode active material is tested using conventional methods. For example, the cathode lithium replenishment material and the cathode active material are dispersed in a suitable liquid or gas, and the Dv50 particle size is measured using a laser particle size analyzer according to GB / T 19077-2016 Particle Size Distribution Laser Diffraction Method. The Dv50 particle size refers to the particle diameter located at 50% of the total volume when the particles are arranged in ascending order of diameter.

[0128] In some embodiments, the positive electrode active layer further includes a positive electrode active material.

[0129] The positive electrode active material includes one or more of lithium-containing phosphates and lithium-containing transition metal oxides; or...

[0130] The positive electrode active material includes one or more of the following: lithium iron phosphate, lithium manganese iron phosphate, lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and compounds obtained by adding other transition metals or non-transition metals to the aforementioned compounds.

[0131] In some embodiments, the positive electrode lithium replenishment material is Li2C2O4, and the electrolyte additive is... Therefore, the combined use of the above-mentioned cathode lithium replenishment materials and electrolyte additives can further improve the battery's energy density, cycle performance, and high-temperature storage performance.

[0132] Table 1 Electrolyte Additives

[0133] In some embodiments, the preparation method of the compound having the structure shown in general formula (I) of this application refers to the following synthetic route:

[0134] The reaction temperature in the first step is controlled between 30 and 60°C; the reaction temperature in the second step is controlled between 10 and 30°C. The second step uses a catalyst such as ruthenium trichloride trihydrate for catalysis, and the oxidant can be sodium hypochlorite, ozone, etc. The definitions of R1, R2, R3, R4, n1, and n2 are as described above.

[0135] [Positive electrode plate]

[0136] During the charging and discharging process of a battery, Li undergoes insertion / extraction and consumption, resulting in varying molar Li content at different discharge states. In the examples of positive electrode active materials in this application, the molar Li content refers to the initial state of the material, i.e., before feeding. When the positive electrode active material is applied to the battery system, the molar Li content changes after charge-discharge cycles.

[0137] In the examples of positive electrode active materials in this application, the molar content of O is only a theoretical value. Oxygen release from the crystal lattice will cause changes in the molar content of oxygen, and the actual molar content of O will fluctuate.

[0138] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0139] In some embodiments, the positive current collector may be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. The composite current collector may include a polymer substrate and a metal layer formed on at least one surface of the polymer substrate. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0140] In some embodiments, the positive electrode active material may be a known battery positive electrode active material. As an example, the positive electrode active material may include at least one of the following materials: lithium phosphates with an olivine structure, lithium transition metal oxides, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium transition metal oxides include, but are not limited to, lithium cobalt oxides (such as LiCoO2), lithium nickel oxides (such as LiNiO2), lithium manganese oxides (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxides, lithium manganese cobalt oxides, lithium nickel manganese oxides, and lithium nickel cobalt manganese oxides (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05At least one of O2 and its modified compounds. Examples of lithium phosphates with an olivine structure include, but are not limited to, lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium manganese iron phosphate, and lithium manganese iron phosphate and carbon composites.

[0141] In some embodiments, the positive electrode active layer may optionally include a binder. As an example, the binder may include at least one selected from polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), PVDF-tetrafluoroethylene-propylene terpolymer, PVDF-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorinated acrylate resin.

[0142] In some embodiments, the positive electrode active layer may optionally include a conductive agent. As an example, the conductive agent may include at least one selected from superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0143] In some embodiments, the positive electrode sheet can be prepared by dispersing the above-mentioned components for preparing the positive electrode sheet, such as positive active material, conductive agent, binder and any other components, in a solvent (e.g., N-methylpyrrolidone) to form a positive electrode slurry; coating the positive electrode slurry onto the positive electrode current collector, and then obtaining the positive electrode sheet after drying, cold pressing and other processes.

[0144] [Negative electrode plate]

[0145] The negative electrode sheet includes a negative current collector and a negative active layer disposed on at least one surface of the negative current collector, the negative active layer including a negative active material.

[0146] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0147] In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, copper foil may be used as the metal foil. The composite current collector may include a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0148] In some embodiments, the negative electrode active material may be a negative electrode active material known in the art for use in batteries. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0149] In some embodiments, the negative electrode active layer may optionally include a binder. As an example, the binder may be selected from at least one of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS).

[0150] In some embodiments, the negative electrode active layer may optionally include a conductive agent. As an example, the conductive agent may be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0151] In some embodiments, the negative electrode active layer may optionally include other additives, such as thickeners (e.g., sodium carboxymethyl cellulose (CMC-Na)).

[0152] In some embodiments, the negative electrode sheet can be prepared by dispersing the components used to prepare the negative electrode sheet, such as the negative electrode active material, conductive agent, binder and any other components, in a solvent (e.g., deionized water) to form a negative electrode slurry; coating the negative electrode slurry onto the negative electrode current collector, and then obtaining the negative electrode sheet after drying, cold pressing and other processes.

[0153] [Electrolytes]

[0154] The electrolyte plays a role in conducting ions between the positive and negative electrode plates.

[0155] In some embodiments, the electrolyte is liquid and includes an electrolyte salt and a solvent.

[0156] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0157] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone.

[0158] In some embodiments, the electrolyte may optionally include other additives. As examples, additives may include negative electrode film-forming additives, positive electrode film-forming additives, and may also include additives that can improve certain battery performance, such as additives that improve battery overcharge performance, additives that improve battery high-temperature or low-temperature performance, etc.

[0159] [Isolation membrane]

[0160] In some embodiments, the battery cell also includes a separator. This application does not impose any particular limitation on the type of separator; any known porous separator with good chemical and mechanical stability can be selected.

[0161] In some embodiments, the material of the separator can be selected from at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation.

[0162] In some implementations, the positive electrode, negative electrode, and separator can be fabricated into an electrode assembly using a winding or stacking process.

[0163] In some embodiments, the battery cell may include an outer packaging. This outer packaging can be used to encapsulate the electrode assembly and electrolyte described above.

[0164] In some embodiments, the outer packaging of the battery cell can be a rigid shell, such as a hard plastic shell, an aluminum shell, or a steel shell. The outer packaging of the battery cell can also be a flexible package, such as a pouch. The material of the flexible package can be plastic; examples of plastics include polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0165] This application does not impose any particular limitation on the shape of the battery cell; it can be cylindrical, square, or any other arbitrary shape. For example, Figure 1 shows a square battery cell 5 as an example.

[0166] In some embodiments, referring to FIG2, the outer packaging may include a housing 51 and a cover plate 53. The housing 51 may include a base plate and side plates connected to the base plate, the base plate and side plates forming a receiving cavity. The housing 51 has an opening communicating with the receiving cavity, and the cover plate 53 can be placed over the opening to close the receiving cavity. The positive electrode sheet, negative electrode sheet, and separator may be formed into an electrode assembly 52 by a winding process or a stacking process. The electrode assembly 52 is encapsulated within the receiving cavity. Electrolyte is immersed in the electrode assembly 52. ​​The number of electrode assemblies 52 contained in the battery cell 5 may be one or more, which can be selected by those skilled in the art according to specific practical needs.

[0167] In some implementations, individual battery cells can be assembled into a battery module. The number of individual battery cells contained in a battery module can be one or more, and the specific number can be selected by those skilled in the art based on the application and capacity of the battery module.

[0168] Figure 3 shows a battery module 4 as an example. Referring to Figure 3, in the battery module 4, multiple battery cells 5 can be arranged sequentially along the length of the battery module 4. Of course, they can also be arranged in any other manner. Furthermore, the multiple battery cells 5 can be fixed in place using fasteners.

[0169] Optionally, the battery module 4 may also include a housing with a receiving space in which multiple battery cells 5 are received.

[0170] In some embodiments, the battery modules described above can also be assembled into a battery pack, and the number of battery modules contained in the battery pack can be one or more, the specific number of which can be selected by those skilled in the art according to the application and capacity of the battery pack.

[0171] Figures 4 and 5 show a battery pack 1 as an example. Referring to Figures 4 and 5, the battery pack 1 may include a battery box and multiple battery modules 4 disposed within the battery box. The battery box includes an upper box 2 and a lower box 3, with the upper box 2 covering the lower box 3 to form a closed space for accommodating the battery modules 4. The multiple battery modules 4 can be arranged in any manner within the battery box.

[0172] In addition, this application also provides an electrical device, which includes at least one of the battery cell, battery module, or battery pack provided in this application. The battery cell, battery module, or battery pack can be used as the power source of the electrical device or as the energy storage unit of the electrical device. The electrical device may include, but is not limited to, mobile devices (e.g., mobile phones, laptops, etc.), electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.

[0173] As an electrical device, you can choose individual battery cells, battery modules, or battery packs according to your usage requirements.

[0174] Figure 6 shows an example of an electrical device. This device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc. To meet the high power and high energy density requirements of the individual battery cells, a battery pack or battery module can be used.

[0175] [Example]

[0176] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0177] Synthesis Example 1: Compound 1-1 Synthesis

[0178] Step 1: Add 300g (2mol) of solid 1,6-dideoxygalactitol to a 2L three-necked flask, start stirring, and add 523g (4.4mol) of thionyl chloride dropwise to the flask. During the dropwise addition, control the temperature at around 15℃. After the dropwise addition is complete, keep the reaction at 45℃ for 4 hours. A large amount of paste-like solid precipitates from the reaction solution. After cooling, slowly add 1L of deionized water. Quickly stir and disperse the reaction system. The filtered solid is washed repeatedly with deionized water until the pH is neutral. Dry the filter cake under reduced pressure at 60℃ to obtain the intermediate product.

[0179] Step 2: Add 184.2 g (0.8 mol) of intermediate product 1 to a 3L three-necked flask, add 1000 mL of acetonitrile, add 80 mg of ruthenium trichloride trihydrate catalyst, purge the system with nitrogen, cool the system to 20°C, start stirring, and add 2000 g of 20% sodium hypochlorite aqueous solution dropwise over 1 hour, controlling the reaction temperature at 10-20°C; after the addition is complete, stir at 10-20°C for 10 minutes, separate the layers, and quench the organic phase with sodium sulfite aqueous solution until the starch-potassium iodide test paper does not turn blue; separate the layers again, concentrate the organic layer, and crystallize the acetonitrile to obtain a white powder solid, which is the above compound 1-1.

[0180] 1H-NMR, CD3CN, δppm 5.42-5.39(m,2H), 5.36-5.34(m,2H), 1.67-1.65(d,6H).

[0181] Synthesis Example 2: Compounds 1-2 Synthesis

[0182] Step 1: Add 356.5g (2mol) of solid 3,4,5,6-octanetetrol to a 2L three-necked flask, start stirring, and add 523g (4.4mol) of thionyl chloride dropwise to the flask. During the dropwise addition, control the temperature at around 15℃. After the dropwise addition is complete, keep the reaction at 45℃ for 4 hours. A large amount of paste-like solid precipitates from the reaction solution. After cooling, slowly add 1L of deionized water. Quickly stir and disperse the reaction system. The filtered solid is washed repeatedly with deionized water until the pH is neutral. Dry the filter cake under reduced pressure at 60℃ to obtain the intermediate product.

[0183] Step 2: Add 216.2 g (0.8 mol) of intermediate product 1 to a 3L three-necked flask, add 1000 mL of acetonitrile and 80 mg of ruthenium trichloride trihydrate catalyst. After purging the system with nitrogen, cool the system to 20°C, start stirring, and add 2000 g of 20% sodium hypochlorite aqueous solution dropwise over 1 hour, controlling the reaction temperature at 10-20°C. After the addition is complete, stir at 10-20°C for 10 minutes, separate the layers, and quench the organic phase with sodium sulfite aqueous solution until the starch-potassium iodide test paper does not turn blue. Separate the layers again, concentrate the organic layer, and crystallize the acetonitrile to obtain compounds 1-2.

[0184] Synthesis Example 3: Compounds 1-3 Synthesis

[0185] Step 1: Add 328.4 g (2 mol) of solid 2,3,4,5-heptachlor to a 2 L three-necked flask, start stirring, and add 523 g (4.4 mol) of thionyl chloride dropwise to the flask. During the dropwise addition, control the temperature at around 15 °C. After the dropwise addition is complete, keep the reaction at 45 °C for 4 h. A large amount of paste-like solid precipitates from the reaction solution. After cooling, slowly add 1 L of deionized water. Quickly stir and disperse the reaction system. The filtered solid is washed repeatedly with deionized water until the pH is neutral. Dry the filter cake under reduced pressure at 60 °C to obtain the intermediate product.

[0186] Step 2: Add 205g (0.8mol) of intermediate product 1 to a 23-necked flask, add 1000mL of acetonitrile, stir until the solid is completely dissolved, add 80mg of ruthenium trichloride trihydrate catalyst, purge the system with nitrogen, cool the system to 20℃, start stirring, and add 2000g of 20% sodium hypochlorite aqueous solution dropwise over 1 hour, controlling the reaction temperature at 10-20℃; after the addition is complete, stir at 10-20℃ for 10min, separate the liquids, and quench the organic phase with sodium sulfite aqueous solution until the starch-potassium iodide test paper does not turn blue; separate the liquids again, concentrate the organic layer, and crystallize the acetonitrile to obtain compounds 1-3 (163.1g, yield 82.8%).

[0187] Synthesis Example 4: Compounds 1-11 Synthesis

[0188] Step 1: Add 392.4 g (2 mol) of solid 1,2,3,4,5,6-heptanhexane to a 2 L three-necked flask, start stirring, and add 784.5 g (6.6 mol) of thionyl chloride dropwise to the flask. During the dropwise addition, control the temperature at around 15 °C. After the dropwise addition is complete, keep the reaction at 45 °C for 4 h. A large amount of paste-like solid precipitates from the reaction solution. After cooling, slowly add 1 L of deionized water. Quickly stir and disperse the reaction system. The filtered solid is washed repeatedly with deionized water until the pH is neutral. Dry the filter cake under reduced pressure at 60 °C to obtain the intermediate product.

[0189] Step 2: Add 140g (0.4mol) of intermediate product 1 to a 4L three-necked flask, add 1000mL of acetonitrile, add 110mg of ruthenium trichloride trihydrate catalyst, purge the system with nitrogen, cool the system to 20℃, start stirring, and add 1500g of 20% sodium hypochlorite aqueous solution dropwise over 1 hour, controlling the reaction temperature at 10-20℃; after the addition is complete, stir at 10-20℃ for 10 minutes, separate the layers, and quench the organic phase with sodium sulfite aqueous solution until the starch-potassium iodide test paper does not turn blue; separate the layers again, concentrate the organic layer, and crystallize the acetonitrile to obtain compound 1-11.

[0190] Synthesis Example 5: Compounds 1-14 Synthesis

[0191] Step 1: Add 484g (2mol) of solid octitol to a 2L three-necked flask, start stirring, and add 1046g (8.8mol) of thionyl chloride dropwise to the flask. During the dropwise addition, control the temperature at around 15℃. After the dropwise addition is complete, keep the reaction at 45℃ for 4 hours. A large amount of paste-like solid precipitates from the reaction solution. After cooling, slowly add 1L of deionized water. Quickly stir and disperse the reaction system. The filtered solid is washed repeatedly with deionized water until the pH is neutral. The filter cake is dried under reduced pressure at 60℃ to obtain the intermediate product.

[0192] Step 2: Add 183.2 g (0.4 mol) of intermediate product to a 4 L three-necked flask, add 1000 mL of acetonitrile, add 150 mg of ruthenium trichloride trihydrate catalyst, purge the system with nitrogen, cool the system to 20 °C, start stirring, and add 2000 g of 20% sodium hypochlorite aqueous solution dropwise over 1 hour, controlling the reaction temperature at 10-20 °C; after the addition is complete, stir at 10-20 °C for 10 min, separate the layers, and quench the organic phase with sodium sulfite aqueous solution until the starch-potassium iodide test paper does not turn blue; separate the layers again, concentrate the organic layer, and crystallize the acetonitrile to obtain compounds 1-14.

[0193] In addition, the synthesis method of the compound is the same as that in Synthesis Example 1, except that 1,6-dideoxygalactitol is replaced with the corresponding substrate in Table 2.

[0194] Table 2

[0195] The preparation methods for compounds 1-4 to 1-8, 1-10, 1-12 to 1-13, and 1-15 are the same as those for the synthesis examples and general formula compounds described above.

[0196] Example 1

[0197] 1. Preparation of positive electrode sheet: The positive active material lithium iron phosphate, the positive lithium supplement material (Li2C2O4, Dv50 particle size of 8μm), the binder polyvinylidene fluoride (PVDF), and the conductive agent acetylene black are dissolved in the solvent N-methylpyrrolidone (NMP) at a mass ratio of 95:2:2:1 and thoroughly stirred and mixed to prepare a positive electrode slurry; the positive electrode slurry is uniformly coated on the positive current collector aluminum foil, and then dried, cold pressed, and slit to obtain the positive electrode sheet.

[0198] 2. Preparation of negative electrode sheet: The negative electrode active material artificial graphite, conductive agent acetylene black, binder styrene-butadiene rubber (SBR), and thickener sodium carboxymethyl cellulose (CMC-Na) are dissolved in deionized water at a mass ratio of 95:2:2:1 and thoroughly stirred and mixed to prepare a negative electrode slurry; the negative electrode slurry is coated on the negative electrode current collector copper foil, and then dried, cold pressed, and slit to obtain the negative electrode sheet.

[0199] 3. Separating membrane: Polypropylene membrane is used.

[0200] 4. The electrolyte includes ethylene carbonate (EC), methyl ethyl carbonate (EMC), LiPF6 and compound 1-1. The volume ratio of ethylene carbonate (EC) to methyl ethyl carbonate (EMC) is 3:7. The concentration of LiPF6 in the electrolyte is 1 mol / L. The mass percentage of compound 1-1 in the electrolyte is 2%.

[0201] 5. Preparation of secondary battery: The above positive electrode sheet, separator and negative electrode sheet are stacked and wound in sequence to obtain electrode assembly; the electrode assembly is placed in outer packaging, the electrolyte prepared above is added, and after processes such as encapsulation, standing, formation and aging, a secondary battery is obtained.

[0202] Examples 2-41 and Comparative Examples 1-3 are similar to the secondary battery preparation method of Example 1, but the product parameters have been adjusted. The different product parameters are detailed in Table 3.

[0203] Battery test

[0204] (1) Test of the ratio of the particle size of the positive electrode lithium supplement material Dv50 to the particle size of the positive electrode active material Dv50:

[0205] The positive electrode active material and the positive electrode lithium supplement material were dispersed in a suitable liquid (e.g., deionized water) or gas by ultrasonic treatment. The Dv50 particle size of the positive electrode lithium supplement material and the positive electrode active material were measured by laser diffraction method for particle size distribution, according to GB / T 19077-2016. The ratio was then calculated.

[0206] (2) Cyclic performance test of lithium-ion batteries at 45℃

[0207] At 45℃, a lithium-ion battery is charged at a constant current of 1C to a voltage of 4.2V, then charged at a constant voltage of 4.2V until the current is ≤0.05C. The battery is then discharged at a constant current of 1C to a voltage of 2.5V. This constitutes one charge-discharge cycle, and the discharge capacity at this point is recorded as the discharge capacity of the battery in its first cycle. This charge-discharge cycle is repeated, and the number of cycles N corresponding to when the battery retains 80% of its capacity is calculated.

[0208] The capacity retention rate (%) of the battery after N cycles at 45℃ = (discharge capacity of the battery in the Nth cycle / discharge capacity of the battery in the first cycle) × 100%.

[0209] (3) Lithium-ion battery storage performance test at 60℃

[0210] In a constant temperature environment of 25℃, the battery is charged to 3.65V at 0.33C and then discharged to 2.5V at 0.33C, and the discharge capacity D1 is tested. The battery is stored in a constant temperature environment of 60℃ and taken out for testing every 30 days. Each time the battery is tested, it is cooled to 25℃, charged to 3.65V at 0.33C and then discharged to 2.5V at 0.33C, and the discharge capacity is tested until the storage days are equal to 90 days, and the capacity retention rate is recorded at this time.

[0211] Battery capacity retention rate (%) after 90 days of storage at 60℃ = (Battery discharge capacity after 90 days of storage / Battery discharge capacity during initial storage D1) × 100%.

[0212] (4) Lithium-ion battery specific capacity test

[0213] At 25°C, the lithium-ion battery was charged at a constant current of 0.33C to 3.65V, then charged at a constant voltage of 3.65V until the current was less than 0.05C. Finally, the lithium-ion battery was discharged at a constant current of 0.33C to 2.5V, and its actual capacity was recorded as C0 (mAh). The specific capacity of the lithium-ion battery is C0 / W3 (mAh / g), where W3 is the total mass (g) of the positive electrode active material and the positive electrode lithium replenishment material.

[0214] (5) DC DCR test of positive electrode plate

[0215] The positive electrode sheet was removed from the battery and cut to 1540.25mm using a punching machine. 2 Circular wafers of the same size were cut out and used as positive and negative electrodes to assemble symmetrical coin cells with identical electrode materials. Using a Chenhua electrochemical workstation (CHI660E), the corresponding current pulse test module was selected. By applying a 4C current fluctuation across the battery terminals, the DC DCR of the symmetrical coin cell was measured at 25℃. Each sample was tested five times, and the average value was calculated to obtain the DC DCR of the positive electrode.

[0216] Table 2: Performance test results of Examples 1-41 and Comparative Examples 1-3

[0217] Based on the above results, we can conclude that:

[0218] Compared with Comparative Example 1, which did not use positive electrode lithium replenishment material and electrolyte additives, the specific capacity, cycle capacity retention rate and specific capacity after high temperature storage of the batteries in Examples 1-41 of this application are significantly improved, and the DCR of the positive electrode is significantly reduced.

[0219] Compared with Comparative Example 2 which did not use electrolyte additives, the battery of Examples 1-37 of this application showed significantly improved cycle capacity retention, high-temperature storage capacity retention, and specific capacity after high-temperature storage, and significantly reduced DCR of the positive electrode.

[0220] Compared with Comparative Example 3, which does not use positive electrode lithium replenishment material, the specific capacity and specific capacity after high-temperature storage of the batteries in Examples 16 and 23-41 of this application are significantly improved.

[0221] Compared with the higher content of positive electrode lithium replenishment material in Example 26, the specific capacity, cycle capacity retention rate and specific capacity after high-temperature storage of the batteries in Examples 16, 23-25 ​​of this application are significantly improved, and the DCR of the positive electrode sheet is significantly reduced.

[0222] Compared with the higher electrolyte additive content in Example 32, the cycle capacity retention rate, high-temperature storage capacity retention rate, and specific capacity after high-temperature storage of the batteries in Examples 16, 27-31 of this application are significantly improved, and the DCR of the positive electrode is significantly reduced.

[0223] Compared with the slightly lower electrolyte additive content in Example 27, the specific capacity, cycle capacity retention, high-temperature storage capacity retention, and specific capacity after high-temperature storage of the batteries in Examples 16, 28-30 of this application are significantly improved, and the DCR of the positive electrode is significantly reduced.

[0224] Compared with the slightly higher electrolyte additive content in Example 31, the cycle capacity retention rate, high-temperature storage capacity retention rate, and specific capacity after high-temperature storage of the batteries in Examples 16, 28-30 of this application are significantly improved, and the DCR of the positive electrode is significantly reduced.

[0225] Compared with the lower Dv50 particle size ratio of the positive electrode lithium replenishment material to the positive electrode active material in Examples 33-34, the specific capacity, cycle capacity retention, high-temperature storage capacity retention, and specific capacity after high-temperature storage of the batteries in Examples 16 and 35-37 of this application are significantly improved.

[0226] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A battery cell, the battery cell comprising an electrode assembly, the electrode assembly comprising a positive electrode sheet, a negative electrode sheet, and a non-aqueous electrolyte, the positive electrode sheet comprising a positive current collector and a positive active layer disposed on the positive current collector, the positive active layer comprising a positive lithium supplementing material, and the non-aqueous electrolyte comprising an electrolyte additive as shown in formula (I); wherein R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a group having a structure shown in Formula (II), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group and a sulfonic acid group, n1 and n2 are each independently any integer of 0-2; or, when n1 is 1 or 2, R 1 or R 2 , and the ring carbon atom to which R 1 or R 2 is attached and the adjacent ring carbon atom form a structure shown in Formula (III); Formula (II) is Formula (III) is R 5 , R 6 , R 7 , and R 8 are each independently selected from any one of a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group; n3 and n4 are each independently any integer of 0-2.

2. The battery cell of claim 1, wherein, R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a group having a structure shown in Formula (II), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group and a sulfonic acid group, and n1 and n2 are each independently any integer of 0-2.

3. The battery cell of claim 1 or 2, wherein, R 1 , R 2 , R 3 , R 4 is simultaneously a hydrogen atom; or R 1 and R 2 are not simultaneously hydrogen atoms and R 3 and R 4 are not simultaneously hydrogen atoms; or R 1 , R 2 , R 3 , R 4 , R 5 and R 6 satisfy the following conditions: R 1 and R 2 are simultaneously hydrogen atoms and R 3 and R 4 one is a hydrogen atom and the other is any one of a group having a structure represented by general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group, and the group having a structure represented by general formula (II) is a group in which R 5 and R 6 are not simultaneously hydrogen atoms; or R 1 , R 2 , R 3 , R 4 , R 5 and R 6 satisfy the following conditions: R 3 and R 4 are simultaneously hydrogen atoms and R 1 and R 2 one is a hydrogen atom and the other is any one of a group having a structure represented by general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, and a sulfonic acid group, and the group having a structure represented by general formula (II) is a group in which R 5 and R 6 are not simultaneously hydrogen atoms; or R 1 , R 2 , R 3 , R 4 , R 5 and R 6 satisfy the following conditions: R 1 and R 2 are simultaneously hydrogen atoms and R 3 and R 4 one is a hydrogen atom and the other is any one of a group having a structure represented by general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, and the group having a structure represented by general formula (II) is a group in which R 5 and R 6 are not simultaneously hydrogen atoms or are simultaneously hydrogen atoms; or R 1 , R 2 , R 3 , R 4 , R 5 and R 6 satisfy the following conditions: R 3 and R 4 are simultaneously hydrogen atoms and R 1 and R 2 one is a hydrogen atom and the other is any one of a group having a structure represented by general formula (II), a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, and the group having a structure represented by general formula (II) is a group in which R 5 and R 6 are not simultaneously hydrogen atoms or are simultaneously hydrogen atoms; or R 1 , R 2 , R 3 and R 4 satisfy the following conditions: R 3 and R 4 are simultaneously hydrogen atoms and R 1 and R 2 one is a hydrogen atom, the other is a hydrogen atom and the ring carbon atom to which they are attached and the adjacent ring carbon atom form a structure represented by the general formula (III), and the group represented by the general formula (III) is a group represented by the general formula (IV) or (V) : 7 and R 8 are not simultaneously hydrogen atoms or are simultaneously hydrogen atoms.

4. The battery cell of any one of claims 1 to 3, wherein, The electrolyte additive has a structure represented by general formula (I-1), wherein R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a group having a structure represented by formula (II-1), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group, a hydroxyl group, and a sulfonic acid group, n1 is any integer from 0 to 2; or, when n1 is 1 or 2, R 1 or R 2 , the ring carbon atom to which R 1 or R 2 is attached and the adjacent ring carbon atom form a structure represented by formula (III-1); Formula (II-1) is Formula (III-1) is R 5 , R 6 , R 7 and R 8 are each independently selected from any one of a hydrogen atom, a halogen atom, a C1-C6alkyl group, a C1-C6haloalkyl group, a C1-C6alkoxy group, a C1-C6haloalkoxy group, a C2-C6alkenyl group, a C2-C6ester group, a cyano group and a sulfonic acid group.

5. The battery cell of any one of claims 1 to 4, wherein, The electrolyte additive has a structure represented by Formula (I-2), wherein R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a group having a structure shown in Formula (II-1), a hydrogen atom, a halogen atom, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a C2-C6 alkenyl group, a C2-C6 ester group, a cyano group and a sulfonic acid group; General Formula (II-1) is R 5 and R 6 each independently is selected from any one of a hydrogen atom, a halogen atom, a C1-C6alkyl group, a C1-C6haloalkyl group, a C1-C6alkoxy group, a C1-C6haloalkoxy group, a C2-C6alkenyl group, a C2-C6ester group, a cyano group, and a sulfonic acid group.

6. The battery cell of any one of claims 1 to 5, wherein one or more of the following: R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a group having a structure represented by formula (II-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C1-C3 haloalkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group, a hydroxyl group and a sulfonic acid group, or, when n1 is 1 or 2, R 1 or R 2 , and the ring carbon atom to which R 1 or R 2 is attached and the adjacent ring carbon atom form a group having a structure represented by formula (III-1); and R 5 , R 6 , R 7 and R 8 are each independently selected from any one of a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C1-C3 haloalkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group and a sulfonic acid group; R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a group having a structure represented by formula (II-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group and a hydroxyl group, or, when n1 is 1 or 2, R 1 or R 2 , and R 1 or R 2 , and the ring carbon atom to which R 5 or R 6 , and R 7 and R 8 are each independently selected from any one of a hydrogen atom, a halogen atom and a C1-C3 alkyl group; R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a group consisting of a radical having a structure shown in Formula (II-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C1-C3 haloalkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group and a sulfonic acid group; and, R 5 and R 6 are each independently selected from any one of a group consisting of a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group, a C1-C3 alkoxy group, a C1-C3 haloalkoxy group, a C2-C3 alkenyl group, a C1-C3 ester group, a cyano group and a sulfonic acid group; R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a group having a structure shown in Formula (II-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group; and, R 5 and R 6 are each independently selected from any one of a hydrogen atom, a halogen atom, a C1-C3 alkyl group, a C1-C3 haloalkyl group. R 1 , R 2 , R 3 , and R 4 are each independently selected from any one of a group having a structure shown in Formula (II-1), a hydrogen atom, an F atom, a Cl atom, a Br atom, a methyl group, an ethyl group, a propyl group, and an isopropyl group; and, R 5 and R 6 are each independently selected from any one of a hydrogen atom, an F atom, a Cl atom, a Br atom, a methyl group, an ethyl group, a propyl group, and an isopropyl group; the group represented by the formula (II-1) is selected from any one of the following groups: X is an F atom, a Cl atom, or a Br atom; R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a hydrogen atom, a F atom, a methyl group, an ethyl group, a propyl group, a monofluoromethyl group, a trifluoromethyl group, a cyano group, a methoxy group, an ethoxy group, a hydroxyl group, a vinyl group and a methoxyformyl group, X is a F atom; or, when n1 is 1, R 1 or R 2 , and the adjacent ring carbon atom form a 1 or R 2 , and the adjacent ring carbon atom form a a group; R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a hydrogen atom, an F atom, a Cl atom, a Br atom, a methyl group, an ethyl group, a propyl group, and an isopropyl group, and X is an F atom; R 1 , R 2 , R 3 and R 4 are each independently selected from any one of a hydrogen atom, a methyl group, and an ethyl group, and X is an F atom.

7. The battery cell of any one of claims 1 to 6, wherein, The electrolyte additive is selected from any one or more of the following compounds:

8. The battery cell of any one of claims 1 to 7, wherein, The positive electrode lithium supplementing material includes Li2C x O y wherein x is any integer in the range of 1-4, y is any integer in the range of 3-6, and x+y=2m, m is any integer in the range of 2-5.

9. The battery cell of any one of claims 1-8, wherein, The positive electrode lithium supplement material includes one or more of Li2C2O4, Li2CO3, Li2C4O4, Li2C3O5, and Li2C4O6.

10. The battery cell of any one of claims 1 to 9, wherein, The mass ratio of the positive electrode lithium supplement material in the positive electrode active layer is 0.05%-10%, 0.1%-8%, or 0.1%-5%.

11. The battery cell of any one of claims 1-10, wherein, The mass ratio of the electrolyte additive in the non-aqueous electrolyte is 0.01%-20%, 0.1%-10%, or 0.5%-5%.

12. The battery cell of any one of claims 1-11, wherein, The mass ratio of the positive electrode lithium supplement material in the positive electrode active layer is W1, the mass ratio of the electrolyte additive in the non-aqueous electrolyte is W2, and W1 / W2 is 0.05-20 or 0.1-5.

13. The battery cell of any one of claims 1-12, wherein, The positive electrode active layer further includes a positive electrode active material, and the ratio of the Dv50 particle size of the positive electrode lithium supplement material to the Dv50 particle size of the positive electrode active material is 1-10 or 5-10.

14. The battery cell of any one of claims 1-13, wherein, The positive electrode active layer further includes a positive electrode active material, The positive electrode active material includes one or more of a lithium-containing phosphate and a lithium-containing transition metal oxide; or The positive electrode active material includes one or more of lithium iron phosphate, lithium manganese iron phosphate, lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and a compound obtained by adding other transition metals or non-transition metals to the foregoing compounds.

15. A battery device comprising the battery cell of any one of claims 1 to 14, the battery device being a battery module, a battery pack, or an energy storage device.

16. An electric device comprising the battery cell of any one of claims 1 to 14 or the battery device of claim 15.

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