Non-aqueous electrolyte, secondary batteries and power consumption devices

Abstract

This application provides a non-aqueous electrolyte, a secondary battery, and a power consumption device. The non-aqueous electrolyte includes an additive, the additive includes a first additive and a second additive, the first additive is one or more cyclic sulfate ester compounds having a structure represented by general formula (I), and the second additive includes one or more of lithium monofluorophosphate, lithium difluorophosphate, lithium tetrafluoroborate, a compound represented by general formula (III), and a fluorosulfonate. JPEG2026518244000045.jpg51170

Description

[Technical Field]

[0001] This application relates to the field of battery technology, and more particularly to non-aqueous electrolytes, secondary batteries, and power consumption devices. [Background technology]

[0002] In recent years, with the advancement of lithium-ion secondary battery technology, lithium-ion secondary batteries have been widely applied in various fields, including energy storage and power systems such as hydroelectric, thermal, wind, and solar power plants, as well as power tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, and aerospace. Due to the rapid development of lithium-ion secondary batteries, higher requirements are being demanded for their rapid charging performance, cycle characteristics, and safety performance.

[0003] Among battery performance requirements, automotive lithium secondary batteries, in particular, demand high power output and long lifespan. Simultaneously, reducing resistance and improving battery lifespan are also crucial challenges. It is known that the continuous reduction of the electrolyte at the negative electrode during the charging process contributes to increased battery resistance and lifespan degradation. To overcome these challenges, methods are being attempted to form a passivation layer called an SEI film on the negative electrode surface by adding multiple compounds to the electrolyte. The SEI film acts as both a good lithium-ion conductor and a poor electron conductor, suppressing the continued progression of lithium consumption reactions and protecting the electrode. Research has shown that forming a stable and high-quality solid electrolyte interface (SEI) film that is uniform, dense, has low impedance, and excellent adhesion is advantageous for improving the electrochemical performance of batteries. However, if the SEI film produced by the electrolyte additive contains a rich amount of organic components such as lithium alkyl, the electrode impedance increases, not only degrading the cell's output characteristics but also potentially causing lithium deposition on the negative electrode, further reducing the cell's lifespan. [Overview of the project] [Problems that the invention aims to solve]

[0004] This application provides a non-aqueous electrolyte, a secondary battery, and a power consumption device that improve the cycle characteristics of a battery. [Means for solving the problem]

[0005] A first aspect of the present application provides a non-aqueous electrolyte containing an additive, the additive comprising a first additive and a second additive, the first additive being one or more cyclic sulfate ester compounds having a structure represented by general formula (I), [ka] However, R 1 , R 2 , R 3 and R 4 Each of the following is independently selected from a group having the structure represented by general 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 each of the following is independently an arbitrary integer between 0 and 2. General formula (II) is [ka] And, R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general 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 n3 is any integer between 0 and 2. The second additive comprises one or more of the following: lithium monofluorophosphate, lithium difluorophosphate, lithium tetrafluoroborate, a compound represented by general formula (III), and a fluorosulfonate. [ka] In general formula (III), M is a metal, and the metal contains one or more selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Ba, Al, Fe, Cu, and Ni; Y represents a boron atom or a phosphorus atom; X represents a halogen atom; R represents a C1-C10 alkylene group, a C1-C10 haloalkylene group, a C6-C20 arylene group, or a C6-C20 haloarylene group, and each group represented by R is optionally substituted with a substituent or a heteroatom; m represents an integer from 1 to 3; n represents an integer from 0 to 4; q represents 0 or 1; a, b, and c represent natural numbers. The fluorosulfonate is (FSO3) y M y+ is y+ a metal ion or an organic cation, and the metal ion is Li + , Na + , K + , Rb + , Cs + , Mg 2+ , Ca 2+ , Ba 2+ , Al 3+ , Fe 2+ , Cu 2+ , Fe 3+ , Ni 2+ and Ni 3+ and includes one or more of the group consisting of.

[0006] [[ID=~40]] The cyclic sulfate additive in the non-aqueous electrolyte forms a highly elastic SEI film on the negative electrode side during the first charge process. Further, by combining with the above second additive, inorganic components such as Li2S, ROSO2Li, carbonate, LiF, borate, and phosphate are also generated on the negative electrode side during the first charge process of the secondary battery. Compared with a single sulfide, the mixed inorganic components are more stable and exhibit higher ionic conductivity and electron blocking ability. Therefore, the generated SEI film blocks electrons more effectively, alleviates the continuous decomposition of the electrolyte at the negative electrode, thereby optimizing the cycle characteristics and storage performance of the cell and significantly improving the life of the cell.

[0007] In any embodiment of the first aspect, R 1 and R 2At the same time, it is not a hydrogen atom and R 3 and R 4 It is not a hydrogen atom at the same time.

[0008] c In any embodiment of the first aspect, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 The following conditions must be met: R 1 and R 2 It is simultaneously a hydrogen atom and R 3 and R 4 One of them is a hydrogen atom, and the other is 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 It is not a hydrogen atom at the same time.

[0009] In any embodiment of the first aspect, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 The following conditions must be met: R 3 and R 4 It is simultaneously a hydrogen atom and R 1 and R 2 One of them is a hydrogen atom, and the other is 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 It is not a hydrogen atom at the same time.

[0010] The above R 1 , R 2 , R 3 and R 4 The base of the compound has substituents, and by introducing substituents such as alkyl groups, it is possible to create an elastic SEI film with longer organic chains on the anode, thereby preventing the SEI film from breaking down in response to volume changes that occur on the anode during the cycling process. By introducing substituents including F and N, it is possible to create an SEI film that participates in film formation on the anode and is rich in more inorganic components such as LiF and Li3N, thereby improving the mechanical strength of the SEI film, improving the stability of the anode SEI film, and further improving the cycle characteristics of the battery.

[0011] In any embodiment of the first aspect, the cyclic sulfate ester compound has a structure represented by general formula (I-1), [ka] R 1 , R 2 , R 3 and R 4 Each of these is independently selected from one of the following: a group having the structure represented by general 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. The general formula (II-1) is [ka] And, R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general 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.

[0012] In any embodiment of the first aspect, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general 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.

[0013] In any embodiment of the first aspect, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general formula (II-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, or a C1-C3 haloalkyl group.

[0014] In any embodiment of the first aspect, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general formula (II-1), a hydrogen atom, a F atom, a Cl atom, a Br atom, a methyl group, an ethyl group, a propyl group, and an isopropyl group.

[0015] In any embodiment of the first aspect, a group having the structure represented by general formula (II-1) is [ka] One of the following groups is selected, where X is a F atom, a Cl atom, or a Br atom.

[0016] In any embodiment of the first aspect, R 1 , R 2 , R3 and R 4 Each is independent of the others. [ka] X is selected from one of the following: hydrogen atom, fluorine atom, chlorine atom, brin atom, methyl group, ethyl group, propyl group, and isopropyl group, and X is a fluorine atom.

[0017] In any embodiment of the first aspect, R 1 , R 2 , R 3 and R 4 Each is independent of the others. [ka] X is selected from one of the following: a hydrogen atom, a methyl group, or an ethyl group, and X is a fluorine atom.

[0018] In any embodiment of the first aspect, the cyclic sulfate compound is [ka] One or more of the following compounds are selected.

[0019] In any embodiment of the first aspect, in general formula (III), the metal comprises one or more selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Ba, Al, Fe, Cu, and Ni, Y represents a boron atom or a phosphorus atom, X represents a halogen atom, R is a C1-C10 alkylene group, a C1-C10 haloalkylene group, a C6-C20 arylene group, or a C6-C20 haloarylene group, and each group representing R is selectively substituted with a substituent or heteroatom, m is an integer from 1 to 3, n is an integer from 0 to 4, and q is 0 or 1.

[0020] In any embodiment of the first aspect, the fluorosulfonate comprises one or more of lithium fluorosulfonate, sodium fluorosulfonate, and potassium fluorosulfonate.

[0021] In any embodiment of the first aspect, the mass percentage of the first additive in the non-aqueous electrolyte is W1, preferably W1 is 0.001% to 20%, and more preferably W1 is 0.1% to 5%. By utilizing cyclic sulfate ester compounds, a sufficiently stable SEI film having an organic-inorganic hybrid with a stronger electron-blocking ability can be formed, thereby not only effectively improving the cycle characteristics of the secondary battery but also improving the output power of the secondary battery.

[0022] In any embodiment of the first aspect, the mass percentage of the second additive in the non-aqueous electrolyte is W2, preferably W2 is 0.001% to 20%, and more preferably W2 is 0.1% to 5%.

[0023] In any embodiment of the first aspect, 0.01 ≤ W1 / W2 ≤ 10, preferably 0.02 ≤ W1 / W2 ≤ 5. By controlling the ratio of the two substances, the types and content of inorganic components generated by both on the negative electrode side are optimized, further enhancing the stability, ionic conductivity, and electron barrier capability of the SEI coating, thereby further optimizing the improvement effect of the overall SEI performance on the cell's cycle characteristics and storage performance.

[0024] In any embodiment of the first aspect, the non-aqueous electrolyte may further contain an electrolyte. Preferably, the electrolyte contains an alkali metal salt-based electrolyte. Preferably, the electrolyte contains a lithium salt or a sodium salt. Preferably, the lithium salt can be one or more selected from the group consisting of lithium hexafluoride phosphate, lithium perchlorate, lithium hexafluoride arsenate, bis(fluorosulfonyl)imide lithium, and bis(trifluoromethanesulfonyl)imide lithium. Preferably, the sodium salt can be one or more selected from the group consisting of sodium hexafluoride phosphate, sodium difluoro(oxalato)borate, sodium perchlorate, bis(fluorosulfonyl)imide sodium, bis(trifluoromethanesulfonyl)imide sodium, and sodium trifluoromethanesulfonate sodium.

[0025] In any embodiment of the first aspect, the non-aqueous electrolyte further includes a non-aqueous solvent. Preferably, the non-aqueous solvent may include any one or more selected from the group consisting of cyclic carbonates, chain carbonates, nitrile solvents, ketone solvents, and sulfone solvents. More preferably, the non-aqueous solvent includes one or more selected from the group consisting of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, diisopropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, n-propyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, tetramethylene sulfone, dimethyl sulfone, methyl ethyl sulfone, diethyl sulfone, tetrahydrofuran, dimethoxyethane, 1,3-dioxolane, acetone, acetonitrile, and n-butyronitrile.

[0026] In any embodiment of the first aspect, the additive may further include one or more selected from the group consisting of sulfate ester compounds, sulfite ester compounds, sultone compounds, disulfonic acid compounds, nitrile compounds, aromatic compounds, isocyanate compounds, phosphazene compounds, cyclic acid anhydride compounds, phosphite ester compounds, phosphate ester compounds, borate ester compounds, and carboxylic acid ester compounds.

[0027] The second aspect of the present application provides a secondary battery including a positive electrode sheet, an electrolyte, a separator, and a negative electrode sheet, and the electrolyte includes any one of the non-aqueous electrolytes described above.

[0028] In any embodiment of the second aspect, the positive electrode sheet includes a positive electrode current collector and a positive electrode film layer provided on one or both sides of the positive electrode current collector, and the lithium ion diffusion coefficient of the positive electrode film layer is Ds. However, 10 -16 cm 2 / s ≦ Ds ≦ 10-5 cm 2 / s, and preferably 10 -13 cm 2 / s ≦ Ds ≦ 10 -9 cm 2 / s.

[0029] In any embodiment of the second aspect, the negative electrode sheet includes a negative electrode current collector and a negative electrode film layer provided on one or both sides of the negative electrode current collector. The porosity of the negative electrode film layer is 30% to 45%, preferably 37% to 42%.

[0030] In any embodiment of the second aspect, the negative electrode film layer contains a negative electrode active material. Preferably, the D V 50 of the negative electrode active material is 6 μm or more, and more preferably, the D V 50 of the negative electrode active material is 15 μm to 20 μm.

[0031] The third aspect of the present application provides a power consumption device including a secondary battery, and the secondary battery includes any one of the above secondary batteries.

[0032] To more clearly explain the technical solutions in the embodiments of the present application, the following briefly describes the drawings necessary for the embodiments of the present application. It should be understood that the following drawings are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

Brief Description of Drawings

[0033] [Figure 1] It is a schematic diagram of a secondary battery according to an embodiment of the present application. [Figure 2] It is an exploded view of a secondary battery according to an embodiment of the present application shown in FIG. 1. [Figure 3] It is a schematic diagram of a battery module according to an embodiment of the present application. [Figure 4] It is a schematic diagram of a battery pack according to an embodiment of the present application. [Figure 5] It is an exploded view of a battery pack according to an embodiment of the present application shown in FIG. 4. [Figure 6] This is a schematic diagram of a power consumption device that uses a secondary battery as a power source according to one embodiment of the present invention. [Modes for carrying out the invention]

[0034] In drawings, the drawings are not drawn according to actual proportions.

[0035] Embodiments of the present application will be described in more detail below with reference to the drawings and examples. The detailed description of the following embodiments and drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, and the present application is not limited to the embodiments described.

[0036] In the following, embodiments specifically disclosing the non-aqueous electrolyte, secondary battery, and power consumption device of the present application will be described in detail with reference to the drawings as appropriate. However, unnecessary detailed explanations may be omitted. For example, detailed explanations of well-known matters and redundant explanations of structures that are actually the same may be omitted. This is to avoid making the following explanation unnecessarily long and to make it easily understandable to those skilled in the art. The drawings and the following explanation are provided to enable those skilled in the art to fully understand the present application and are not intended to limit the topics described in the claims.

[0037] The “range” disclosed herein is limited in the form of a lower and upper limit, and a given range is limited by selecting one lower limit and one upper limit, the selected lower and upper limits defining the boundaries of a particular range. Ranges defined in this manner may or may not include the values ​​at both ends and can be combined in any way, that is, any lower limit can be combined with any upper limit to form a range. For example, if the ranges 60-120 and 80-110 are listed for a particular parameter, it is understood that the ranges 60-110 and 80-120 are also expected. Similarly, if the minimum range values ​​1 and 2 are listed, and the maximum range values ​​3, 4 and 5 are listed, the ranges 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5 are all intended. In this application, unless otherwise specified, the numerical range “a-b” means an abbreviated expression for any combination of real numbers between a and b, where both a and b are real numbers. For example, the numerical range "0 to 5" means that all real numbers between "0 to 5" are listed in this specification, and "0 to 5" is merely an abbreviated expression for combinations of these numbers. Also, when a parameter is described 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.

[0038] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical inventions.

[0039] Unless otherwise specified, all technical features and optional technical features of this application can be combined to form new technical concepts.

[0040] Unless otherwise specified, all steps of the present invention 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 steps (b) and (a) performed sequentially. For example, if the method may further 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 steps (a), (c), and (b), or steps (c), (a), and (b), etc.

[0041] As used herein, “includes” and “inclusive” refer to both open and closed forms unless otherwise specified. For example, “includes” and “inclusive” may include or include other components not listed, or may include or include only the listed components.

[0042] In this application, unless otherwise specified, the term “or” is inclusive. For example, the phrase “A or B” means “A, B, or both A and B.” More specifically, the condition “A or B” is satisfied by either A being true (or existing) and B being false (or not existing), A being false (or not existing) and B being true (or existing), or both A and B being true (or existing).

[0043] [Secondary battery] Secondary batteries, also known as rechargeable batteries or storage batteries, are batteries that can be used continuously by reactivating the active material through a charging method after the battery has been discharged.

[0044] Generally, a secondary battery includes a positive electrode sheet, a negative electrode sheet, a separator, and an electrolyte. During the charging and discharging process of the battery, active ions (e.g., lithium ions) reciprocate between the positive and negative electrode sheets, being inserted and removed. The separator is placed between the positive and negative electrode sheets and primarily serves to prevent short circuits between the positive and negative electrodes while also allowing active ions to pass through. The electrolyte primarily serves to conduct active ions between the positive and negative electrode sheets.

[0045] [Nonaqueous electrolyte] One embodiment of the present application provides a non-aqueous electrolyte containing an additive, the additive comprising a first additive and a second additive, the first additive being one or more cyclic sulfate ester compounds having a structure represented by general formula (I), [ka] However, R 1 , R 2 , R 3 and R 4 Each of the following is independently selected from a group having the structure represented by general 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 each of the following is independently an arbitrary integer between 0 and 2. General formula (II) is [ka] And, R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general 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 n3 is any integer between 0 and 2. The second additive is one or more of lithium monofluorophosphate, lithium difluorophosphate, lithium tetrafluoroborate, a compound represented by general formula (III), and a fluorosulfonate. [ka] In general formula (III), M is a metal, and the metal includes one or more selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Ba, Al, Fe, Cu, and Ni; Y represents a boron atom or a phosphorus atom; X represents a halogen atom; R represents a C1-C10 alkylene group, a C1-C10 haloalkylene group, a C6-C20 arylene group, or a C6-C20 haloarylene group, where each group representing R is selectively substituted with a substituent or heteroatom; m represents an integer from 1 to 3; n represents an integer from 0 to 4; q represents 0 or 1; and a, b, and c represent natural numbers. Fluorosulfonates are (FSO3) y M y+ And M y+ is a metal ion or organic cation, and the metal ion is Li + na + , K + , Rb + , Cs + Mg 2+ Ca 2+ Ba 2+ , Al 3+ Fe 2+ Cu 2+ Fe 3+ Ni 2+ and Ni 3+ It includes one or more of the groups consisting of the following.

[0046] The cyclic sulfate ester additive in the non-aqueous electrolyte forms a highly elastic SEI film on the negative electrode side during the initial charging process. Furthermore, when combined with the second additive, inorganic components such as Li2S, ROSO2Li, carbonates, LiF, borates, and phosphates are also generated on the negative electrode side during the initial charging process of the secondary battery. Compared to a single sulfide, the mixed inorganic components are more stable and exhibit higher ionic conductivity and electron barrier capability. Therefore, the generated SEI film more effectively barriers electrons, mitigating the continuous decomposition of the electrolyte at the negative electrode. This optimizes the cell's cycle characteristics and storage performance, significantly improving the cell's lifespan.

[0047] In some embodiments, the above R 1 and R 2 It is not a hydrogen atom and also R 3 and R 4 It is not a hydrogen atom at the same time. Naturally, R 1 , R 2 , R 3 , R 4 It may also be a hydrogen atom.

[0048] In some embodiments, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 The following conditions must be met: R 1 and R 2 It is simultaneously a hydrogen atom and R 3 and R 4 One of them is a hydrogen atom, and the other is 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 It is not a hydrogen atom at the same time.

[0049] In some embodiments, R1 , R 2 , R 3 , R 4 , R 5 and R 6 The following conditions must be met: R 3 and R 4 It is simultaneously a hydrogen atom and R 1 and R 2 One of them is a hydrogen atom, and the other is 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 It is not a hydrogen atom at the same time.

[0050] The above R 1 , R 2 , R 3 and R 4 The base of the compound has substituents, and by introducing substituents such as alkyl groups, it is possible to create an elastic SEI film with longer organic chains on the anode, thereby preventing the SEI film from breaking down in response to volume changes that occur on the anode during the cycling process. By introducing substituents including F and N, it is possible to create an SEI film that participates in film formation on the anode and is rich in more inorganic components such as LiF and Li3N, thereby improving the mechanical strength of the SEI film, improving the stability of the anode SEI film, and further improving the cycle characteristics of the battery.

[0051] The alkyl group mentioned above may be a linear alkyl group, a branched alkyl group, or a cycloalkyl group, and includes, but is not limited to, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a cyclopropyl group, and a cyclobutyl group. The alkyl group of the haloalkyl group mentioned above may include, but is not limited to, a linear alkyl group, a branched alkyl group, or a cycloalkyl group, and may include, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a cyclopropyl group, a cyclobutyl group, and the like. The halogen atom may be a fluorine atom, a chlorine atom, or a bromine atom, and the halogen atom substitutes for one or more hydrogen atoms in the alkyl group. The alkoxy group mentioned above includes, but is not limited to, cyclopropyl and oxetanyl. The halogen atom of the haloalkoxy group may be a fluorine atom, a chlorine atom, or a bromine atom, and the halogen atom substitutes for one or more hydrogen atoms in the alkoxy group. The alkenyl group includes, but is not limited to, -CH=CH2, -CH=CH2CH3, -CH2CH=CH2, and -CH2CH=CH2CH3. Ester groups include, but are not limited to, methyl formate, ethyl formate, ethyl acetate, methyl propionate, ethyl propionate, and propyl propionate.

[0052] In some embodiments, the cyclic sulfate ester compound has a structure represented by general formula (I-1), [ka] R 1 , R 2 , R 3 and R 4 Each of these is independently selected from one of the following: a group having the structure represented by general 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. The general formula (II-1) is [ka] And, R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general 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.

[0053] In the general formula (I-1) above, all the rings of the cyclic sulfate ester are five-membered rings, which allows for the formation of a denser SEI film. Compared to six-membered rings, five-membered rings have greater ring strain and are easier to deposit on the positive and negative electrodes. Six-membered rings, on the other hand, have less ring strain and higher stability, but their deposition on the negative electrode is slower, resulting in lower efficiency in generating an electron-blocking SEI film and affecting the effectiveness of the SEI film.

[0054] In some embodiments, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general 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.

[0055] In some embodiments, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general formula (II-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, or a C1-C3 haloalkyl group.

[0056] In some embodiments, R 1 , R 2 , R 3 , R 4 , R 5 and R 6 Each of these is independently selected from one of the following: a group having the structure represented by general formula (II-1), a hydrogen atom, a F atom, a Cl atom, a Br atom, a methyl group, an ethyl group, a propyl group, and an isopropyl group.

[0057] In some embodiments, a group having the structure represented by general formula (II-1) is [ka] One of the following groups is selected, where X is an F atom, a Cl atom, or a Br atom. Preferably, R 1 , R 2 , R 3 and R 4 Each is independent of the others. [ka] X is selected from one of the following: hydrogen atom, F atom, Cl atom, Br atom, methyl group, ethyl group, propyl group, and isopropyl group, and X is an F atom. In some embodiments, R 1 , R 2 , R 3 and R 4 Each is independent of the others. [ka] X is selected from one of the following: a hydrogen atom, a methyl group, or an ethyl group, and X is a fluorine atom.

[0058] In some embodiments, the cyclic sulfate ester compound is [ka] One or more of the following compounds are selected.

[0059] Some of the above-mentioned cyclic sulfate ester compounds are produced using simpler methods, which are advantageous for industrial dissemination and implementation. Furthermore, the improvement effect on the lifespan of secondary batteries is more stable.

[0060] In some embodiments, in the above general formula (III), the metal comprises one or more selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Ba, Al, Fe, Cu, and Ni, Y represents a boron atom or a phosphorus atom, X represents a halogen atom, R is a C1-C10 alkylene group, a C1-C10 haloalkylene group, a C6-C20 arylene group, or a C6-C20 haloarylene group, and each group representing R is selectively substituted with a substituent or heteroatom, m is an integer from 1 to 3, n is an integer from 0 to 4, and q is 0 or 1.

[0061] In some embodiments, the substituent in general formula (III) substitutes one or more hydrogen atoms in R, and the substituent is selected from a common group, for example, one of halogen atoms, -CN, -NCO, -OH, -COOH, -SOOH, -OC=(O)alkyl groups, -C=(O)O alkyl groups, C1-C10 alkyl groups, C2-C10 alkenyl groups, C2-C10 alkynyl groups, and C2-C10 alkoxy groups. In some embodiments, the heteroatom in general formula (III) substitutes a carbon atom in the carbon chain of R, and it may be one or more of nitrogen atoms, sulfur atoms, phosphorus atoms, and boron atoms.

[0062] In some embodiments, the compound of general formula (III) is selected from one or more of the compounds of lithium difluorobis(oxalato) phosphate, lithium tetrafluoro(oxalato) phosphate, lithium tris(oxalato) phosphate, lithium difluoro(oxalato) borate, lithium bis(oxalato) borate, lithium difluorobis(malonato) phosphate, lithium tetrafluoro(malonato) phosphate, lithium tris(malonato) phosphate, lithium difluoro(malonato) borate, and lithium bis(malonato) borate, preferably one or more of lithium difluorobis(oxalato) phosphate, lithium tetrafluoro(oxalato) phosphate, lithium difluoro(oxalato) borate, and lithium bis(oxalato) borate.

[0063] In some embodiments, the fluorosulfonate comprises one or more of lithium fluorosulfonate, sodium fluorosulfonate, and potassium fluorosulfonate.

[0064] The amount of cyclic sulfate ester compound used in each of the above embodiments of this application can refer to the amount of general-purpose cyclic sulfate ester compound used in general-purpose non-aqueous electrolytes. In some embodiments, the mass percentage of the first additive in the non-aqueous electrolyte is W1, preferably W1 is 0.001% to 20%, for example 0.001%, 0.005%, 0.01%, 0.05%, 0.1%, 0.5%, 1%, 3%, 5%, 10%, 15%, or 20%, and more preferably W1 is 0.1% to 5%. By utilizing cyclic sulfate ester compounds, it is possible to sufficiently form an organic-inorganic hybrid SEI film that is more stable and has a stronger electron-blocking ability, thereby not only effectively improving the cycle characteristics of secondary batteries but also improving the output power of secondary batteries. By limiting the above mass content, we can avoid situations where the cyclic sulfate ester compound content is too low, preventing the SEI coating from functioning properly. Furthermore, we can avoid situations where the cyclic sulfate ester compound content is too high, causing the electrolyte viscosity to become excessively high and the SEI coating formed on the negative electrode to become too thick, degrading the conductivity of the electrolyte and reducing the improvement effect on cycle characteristics and charging capacity.

[0065] In some embodiments of the present application, the mass percentage of the second additive in the non-aqueous electrolyte is W2, preferably W2 is 0.001% to 20%, for example 0.001%, 0.005%, 0.01%, 0.05%, 0.1%, 0.5%, 1%, 3%, 5%, 10%, 15%, or 20%, and more preferably W2 is 0.1% to 5%. By using the second additive sufficiently, the stability of the SEI coating is improved, and the cycle characteristics and storage performance of the cell are further improved.

[0066] In some embodiments, 0.01 ≤ W1 / W2 ≤ 10, preferably 0.02 ≤ W1 / W2 ≤ 5. By controlling the ratio of the two substances, the types and content of inorganic components generated by both on the negative electrode side are optimized, further enhancing the stability, ionic conductivity, and electron barrier capability of the SEI coating, thereby further optimizing the improvement effect of the overall SEI performance on the cell's cycle characteristics and storage performance.

[0067] In some embodiments, the non-aqueous electrolyte further comprises an electrolyte, and any common electrolyte used in non-aqueous electrolytes can be considered for application to the non-aqueous electrolyte of this application. Those skilled in the art can select an electrolyte suitable for lithium-ion secondary batteries or sodium-ion secondary batteries, depending on the battery system to which the non-aqueous electrolyte is applied. In some embodiments, the electrolyte preferably comprises an alkali metal salt-based electrolyte. Preferably, the electrolyte comprises a lithium salt or a sodium salt. Preferably, the lithium salt can be one or more selected from the group consisting of lithium hexafluoride phosphate, lithium perchlorate, lithium hexafluoride arsenate, bis(fluorosulfonyl)imide lithium, and bis(trifluoromethanesulfonyl)imide lithium. Preferably, the sodium salt can be one or more selected from the group consisting of sodium hexafluoride phosphate, sodium difluoro(oxalato)borate, sodium perchlorate, sodium bis(fluorosulfonyl)imide sodium, bis(trifluoromethanesulfonyl)imide sodium, and sodium trifluoromethanesulfonate sodium.

[0068] The lithium salts or sodium salts mentioned above can be used individually or in mixtures of two or more types.

[0069] The electrolyte content in the non-aqueous electrolyte may refer to the electrolyte content in a general-purpose non-aqueous electrolyte. In some embodiments, the electrolyte content in the non-aqueous electrolyte is 0.1 mol / L to 5 mol / L, for example, 0.1 mol / L, 0.3 mol / L, 0.5 mol / L, 1 mol / L, 1.5 mol / L, 2 mol / L, 2.5 mol / L, 3 mol / L, 4 mol / L, or 5 mol / L. Preferably, it is 0.5 mol / L to 1.5 mol / L, and more preferably 0.7 mol / L to 1.2 mol / L.

[0070] In some embodiments, the non-aqueous electrolyte further comprises a non-aqueous solvent. Preferably, the non-aqueous solvent may comprise one or more selected from the group consisting of cyclic carbonates, linear carbonates, nitrile solvents, ketone solvents, and sulfone solvents. More preferably, the non-aqueous solvent includes one or more selected from the group consisting of ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, diisopropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, n-propyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, tetramethylene sulfone, dimethyl sulfone, methyl ethyl sulfone, diethyl sulfone, tetrahydrofuran, dimethoxyethane, 1,3-dioxolane, acetone, acetonitrile, and n-butyronitrile. The above non-aqueous solvents can be used alone or in mixtures of two or more. For example, a mixture of a cyclic carbonate solvent and a linear carbonate solvent can be used to improve the load characteristics and low-temperature characteristics of a secondary battery. When the non-aqueous electrolyte of this application is applied to a solid battery, a solid solvent such as dimethyl sulfone can be used.

[0071] The additives may include not only those listed above, but also negative electrode film-forming additives, positive electrode film-forming additives, and further, additives that can improve specific characteristics of the battery, such as additives that improve the overcharge characteristics of the battery, or additives that improve the high-temperature or low-temperature characteristics of the battery. In some embodiments, the additives may further include, but are not limited to, one or more selected from the group consisting of sulfate ester compounds, sulfite ester compounds, sultone compounds, disulfonic acid compounds, nitrile compounds, aromatic compounds, isocyanate compounds, phosphazene compounds, cyclic acid anhydride compounds, phosphite ester compounds, phosphate ester compounds, borate ester compounds, and carboxylic acid ester compounds.

[0072] [Method for producing cyclic sulfate ester compounds having the structure represented by general formula (I)] For a method of producing a cyclic sulfate ester compound having the structure represented by general formula (I) of this application, please refer to the following synthesis route. [ka]

[0073] The reaction temperature in the first step is controlled to 30-60°C, and the reaction temperature in the second step is controlled to 10-30°C. In the second step, a catalyst such as ruthenium trichloride trihydrate is used for catalytic action, and the oxidizing agent may be sodium hypochlorite, ozone, etc.

[0074] [Positive electrode sheet] A positive electrode sheet generally includes a positive electrode current collector and a positive electrode film layer provided on at least one surface of the positive electrode current collector.

[0075] For example, the positive electrode current collector has two opposing surfaces in its own thickness direction, and the positive electrode film layer is provided on one or both of the two opposing surfaces of the positive electrode current collector.

[0076] In some embodiments, the positive electrode current collector can be a metal foil or a composite current collector. As the metal foil, for example, aluminum foil can be used. The composite current collector may include a polymer substrate layer and a metal layer formed on at least one surface of the polymer substrate layer. The composite current collector can be formed by forming a metal material (e.g., aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy) on a polymer material substrate (e.g., a substrate such as polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE)).

[0077] In some embodiments, the lithium ion diffusion coefficient of the positive electrode film layer is Ds, where 10 -16 cm2 / s≦Ds≦10 -5 cm 2 / s, preferably 10 -13 cm 2 / s≦Ds≦10 -9 cm 2 The positive electrode film layer is preferably a positive electrode active material, and any known positive electrode active material satisfying the above conditions in the art can be used. For example, the positive electrode active material may include at least one of olivine-structured lithium-containing phosphates, lithium transition metal oxides, and modified compounds thereof. However, the present application is not limited to these materials, and other conventional materials usable as positive electrode active materials for batteries may be used. These positive electrode active materials may be used individually or in combination of two or more. Examples of lithium transition metal oxides include lithium cobalt oxide (e.g., LiCoO2), lithium nickel oxide (e.g., LiNiO2), lithium manganese oxide (e.g., LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2(NCM 333 (Also known as), LiNi 0.5 Co 0.2 Mn 0.3 O2(NCM 523 (Also known as) LiNi 0.5 Co 0.25 Mn 0.25 O2(NCM 211 (Also known as), LiNi 0.6 Co 0.2 Mn 0.2 O2(NCM 622 (Also known as), LiNi 0.8 Co 0.1 Mn 0.1 O2(NCM 811 (also known as), lithium nickel cobalt aluminum oxide (e.g., LiNi 0.85 Co 0.15 Al 0.05The olivine structure lithium-containing phosphate may include, but is not limited to, at least one of O2 and its modified compounds. The olivine structure lithium-containing phosphate may include, but is not limited to, at least one of lithium iron phosphate (e.g., LiFePO4 (also called LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (e.g., LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon.

[0078] In some embodiments, the positive electrode film layer may selectively further contain a binder. As an example, the binder may include at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorine-containing acrylate resins.

[0079] In some embodiments, the positive electrode film layer may further selectively contain a conductive agent. As an example, the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0080] In some embodiments, a positive electrode sheet can be manufactured by the following method: Components for manufacturing the positive electrode sheet, such as a positive electrode active material, a conductive agent, a binder, and any other components, are dispersed in a solvent (e.g., N-methylpyrrolidone) to form a positive electrode paste, the positive electrode paste is applied to a positive electrode current collector, and the positive electrode sheet can be obtained through processes such as drying and cold pressing.

[0081] [Negative electrode sheet] The negative electrode sheet includes a negative electrode active material and a negative electrode current collector and a negative electrode film layer installed on at least one surface of the negative electrode current collector.

[0082] For example, the negative electrode current collector has two opposing surfaces in its own thickness direction, and the negative electrode film layer is provided on one or both of the two opposing surfaces of the negative electrode current collector.

[0083] In some embodiments, the negative electrode current collector can be a metal foil or a composite current collector. For example, copper foil can be used as the metal foil. The composite current collector may include a polymer substrate layer and a metal layer formed on at least one surface of the polymer substrate. The composite current collector can be formed by forming a metal material (e.g., copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys) on a polymer material substrate (e.g., a substrate such as polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE)).

[0084] In some embodiments, the negative electrode active material can be any negative electrode active material for batteries known in the art. For example, the negative electrode active material may include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. Silicon-based materials can be selected from at least one of elemental silicon, silicon oxide, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials can be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other conventional materials usable as negative electrode active materials for batteries may be used. These negative electrode active materials may be used individually or in combination of two or more types.

[0085] In some embodiments, the porosity of the negative electrode film layer is 30% to 45%, preferably 37% to 42%. If the porosity of the negative electrode film layer on the negative electrode sheet is less than 30%, there are few pores between the particles in the negative electrode film layer, and the particle structure is destroyed by compression, making it difficult for the electrolyte to penetrate. As a result, the cell's polarization increases, and its long-term cycle characteristics deteriorate. On the other hand, if the porosity of the negative electrode film layer on the negative electrode sheet exceeds 45%, the rebound of the polar sheet is large, reducing the compression of the polar sheet during actual use and negatively affecting the energy density of the cell.

[0086] The porosity of the negative electrode active material coating layer on the negative electrode sheet is measured using the AccuPyc II 1340 true density meter, in accordance with the instrument's instruction manual. The porosity of the negative electrode active material coating layer on the polar sheet can be controlled by adjusting the particle size of the negative electrode active material and the pressure during the cold pressing process.

[0087] In some embodiments, the negative electrode active material layer comprises a negative electrode active material, preferably a negative electrode active material of D V 50 is 6 μm or larger, and more preferably the negative electrode active material D V 50 is 15 μm to 20 μm. The first and second additives form an SEI film of a certain thickness on the surface of the negative electrode sheet, thereby increasing the volume particle size of the negative electrode active material. This reduces the contact area between the negative electrode active material and the electrolyte, thereby reducing side reactions on the negative electrode surface and improving the cell's cycle characteristics and storage performance.

[0088] In this application, the volume-average particle size Dv50 of the negative electrode active material has a meaning known in the art and can be measured using apparatus and methods known in the art. For example, it may be measured using a laser particle size analyzer (e.g., MasterSize3000) as described in GB / T19077-2016 "Laser Diffraction Method for Particle Size Distribution".

[0089] In some embodiments, the negative electrode film layer may selectively further contain a binder. For example, the binder can 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).

[0090] In some embodiments, the negative electrode film layer may further selectively contain a conductive agent. As an example, the conductive agent can be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0091] In some embodiments, the negative electrode film layer further comprises other additives, such as a selective thickener (e.g., sodium carboxymethylcellulose (CMC-Na)).

[0092] In some embodiments, a negative electrode sheet can be manufactured by the following method: Components for manufacturing the negative electrode sheet, such as a negative electrode active material, a conductive agent, a binder, and any other components, are dispersed in a solvent (e.g., deionized water) to form a negative electrode paste, the negative electrode paste is coated onto a negative electrode current collector, and the negative electrode sheet can be obtained through steps such as drying and cold pressing.

[0093] [Separator] In some embodiments, the secondary battery further includes a separator. The present application does not particularly limit the type of separator, and any known porous structure separator having good chemical and mechanical stability can be selected.

[0094] 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 may be a single-layer film or a multilayer composite film, and is not particularly limited. If the separator is a multilayer composite film, the materials of each layer may be the same or different, and are not particularly limited.

[0095] In some embodiments, the positive electrode sheet, negative electrode sheet, and separator can be manufactured into an electrode assembly via a winding process or a lamination process.

[0096] In some embodiments, the secondary battery may include an outer casing. This casing is used to enclose the electrode assembly and electrolyte.

[0097] In some embodiments, the casing material of the secondary battery may be a hard case such as a rigid plastic case, an aluminum case, or a steel case. The casing material of the secondary battery may also be a soft pack such as a pouch-type soft pack. The material of the soft pack may be plastic, and examples of plastics include polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0098] This invention does not particularly limit the shape of the secondary battery, and it may be cylindrical, prismatic, or any other shape. For example, Figure 1 shows a prismatic secondary battery 5 as an example.

[0099] In some embodiments, referring to Figure 2, the exterior material may include a housing 51 and a cover plate 53. The housing 51 may include a bottom plate and side plates connected to the bottom plate, forming a housing cavity enclosed by the bottom plate and side plates. The housing 51 has an opening that communicates with the housing cavity, and the cover plate 53 can cover the opening to seal the housing cavity. The positive electrode sheet, negative electrode sheet, and separator can form an electrode assembly 52 via a winding or lamination process. The electrode assembly 52 is sealed within the housing cavity. The electrolyte is impregnated into the electrode assembly 52. ​​The number of electrode assemblies 52 included in the secondary battery 5 may be one or more, and those skilled in the art can select according to specific practical requirements.

[0100] In some embodiments, the secondary batteries can be assembled into a battery module, and the number of secondary batteries included in the battery module may be one or more, the specific number of which can be selected by those skilled in the art depending on the application and capacity of the battery module.

[0101] Figure 3 shows an example of a battery module 4. Referring to Figure 3, in the battery module 4, multiple secondary batteries 5 can be installed in sequence along the length of the battery module 4. Of course, they can be arranged in any other way. Furthermore, these multiple secondary batteries 5 can be fixed in place with fasteners.

[0102] Selectively, the battery module 4 may further comprise an outer case having a housing space for accommodating multiple secondary batteries 5.

[0103] In some embodiments, the battery modules can be further assembled into a battery pack, and the number of battery modules included in the battery pack may be one or more, the specific number of which can be selected by those skilled in the art depending on the application and capacity of the battery pack.

[0104] Figures 4 and 5 show an example of a battery pack 1. Referring to Figures 4 and 5, the battery pack 1 may include a battery case and a plurality of battery modules 4 installed inside the battery case. The battery case includes an upper housing 2 and a lower housing 3, the upper housing 2 can be placed over the lower housing 3 and form a sealed space for housing the plurality of battery modules 4. The plurality of battery modules 4 can be arranged inside the battery case in any way.

[0105] Furthermore, the present application provides a power consumption device comprising at least one of a secondary battery, a battery module, or a battery pack relating to the present application. The secondary battery, battery module, or battery pack may be used as a power source for the power consumption device, or as an energy storage element for the power consumption device. The power consumption 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.), trains, ships and satellites, energy storage systems, etc.

[0106] As the power consumption device, a secondary battery, battery module, or battery pack can be selected according to the usage requirements.

[0107] Figure 6 shows an example of a power consumption device. This power consumption device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc. To meet the high power output and high energy density requirements for the secondary battery of this power consumption device, a battery pack or battery module can be used. [Examples]

[0108] [Examples] Examples of the present application are described below. The examples described below are illustrative and are for interpretive purposes only, and should not be considered as limitations thereon. Where no specific techniques or conditions are shown in the examples, they should be carried out in accordance with the techniques or conditions described in the literature in the art, or in accordance with the product instructions. Where the manufacturer of the reagents or equipment used is not specified, they are all commercially available common products. Information on other reagents or compounds is provided in Table 1.

[0109] [Table 1]

[0110] Synthesis example 1: Compound 1 [ka] synthesis Step 1: Add 300 g (2 mol) of 1,6-dideoxyhexitol solid to a 2 L three-necked flask and start stirring. Add 523 g (4.4 mol) of thionyl chloride dropwise to the three-necked flask, controlling the temperature to approximately 15°C during the addition process. After the addition is complete, the reaction is kept warm at 45°C for 4 hours. A large amount of paste-like solid precipitates in the reaction solution. After cooling, 1 L of deionized water is slowly added dropwise, the reaction system is rapidly stirred to disperse, and the solid obtained by filtration is washed by beating it multiple times with deionized water until the pH becomes neutral. The filtration cake is dried under reduced pressure at 60°C to obtain the intermediate product.

[0111] Step 2: Add 184.2 g (0.8 mol) of intermediate product 1 to a 3 L three-necked flask, add 1000 mL of acetonitrile, add 80 mg of ruthenium trichloride trihydrate catalyst, purge the system with nitrogen gas, cool the system to 20°C, start stirring, and within 1 hour add 2000 g of 20% sodium hypochlorite aqueous solution dropwise to control the reaction temperature to 10-20°C. After the dropwise addition is complete, stir for 10 minutes at 10-20°C, separate the liquid and quench the organic phase with sodium sulfite aqueous solution until the potassium iodide starch test paper no longer turns blue. Separate the liquid and quench the organic layer again, concentrate it, and crystallize it with acetonitrile to obtain a white powder solid, which is compound 1-1.

[0112] 1H-NMR, CD3CN, δ ppm 5.42-5.39 (m, 2H), 5.36-5.34 (m, 2H), 1.67-1.65 (d, 6H).

[0113] Synthesis example 2: Compound 2 [ka] synthesis Step 1: Add 356.5 g (2 mol) of 3,4,5,6-octanetetraol solid to a 2 L three-necked flask and start stirring. Add 523 g (4.4 mol) of thionyl chloride dropwise to the three-necked flask, controlling the temperature to approximately 15°C during the dropwise addition process. After addition is complete, the reaction is kept warm at 45°C for 4 hours, and a large amount of paste-like solid precipitates in the reaction solution. After cooling, 1 L of deionized water is slowly added dropwise, the reaction system is rapidly stirred to disperse, the solid is filtered, and the obtained solid is washed by beating it multiple times with deionized water until the pH becomes neutral. The filtered cake is dried under reduced pressure at 60°C to obtain the intermediate product.

[0114] Step 2: Add 216.2 g (0.8 mol) of intermediate product 1 to a 3 L three-necked flask, add 1000 mL of acetonitrile, add 80 mg of ruthenium trichloride trihydrate catalyst, purge the system with nitrogen gas, cool the system to 20°C, start stirring, and within 1 hour add 2000 g of 20% sodium hypochlorite aqueous solution dropwise to control the reaction temperature to 10-20°C. After the dropwise addition is complete, stir at 10-20°C for 10 minutes, separate the liquid and quench the organic phase with sodium sulfite aqueous solution until the potassium iodide starch test paper no longer turns blue, separate the liquid and quench again, concentrate the organic layer, and crystallize it with acetonitrile to obtain compound 2.

[0115] Synthesis example 3: Compound 3 [ka] synthesis Step 1: Add 328.4 g (2 mol) of 2,3,4,5-heptanetetraol solid to a 2 L three-necked flask and start stirring. Add 523 g (4.4 mol) of thionyl chloride dropwise to the three-necked flask, controlling the temperature to approximately 15°C during the addition process. After the addition is complete, the reaction is incubated at 45°C for 4 hours, and a large amount of paste-like solid precipitates in the reaction solution. After cooling, 1 L of deionized water is slowly added dropwise, the reaction system is rapidly stirred to disperse, the solid is filtered, and the obtained solid is washed by beating it multiple times with deionized water until the pH becomes neutral. The filtered cake is dried under reduced pressure at 60°C to obtain the intermediate product.

[0116] Step 2: Add 205 g (0.8 mol) of intermediate product 1 to a 3 L three-necked flask, add 1000 mL of acetonitrile, and stir until the solid is completely dissolved. Add 80 mg of ruthenium trichloride trihydrate catalyst, purge the system with nitrogen gas, cool to 20°C, start stirring, and within 1 hour add 2000 g of 20% sodium hypochlorite aqueous solution dropwise to control the reaction temperature to 10-20°C. After the dropwise addition is complete, stir for 10 min at 10-20°C, separate, and quench the organic phase with sodium sulfite aqueous solution until the potassium iodide starch test strip no longer turns blue. Separate again, concentrate the organic layer, and crystallize it with acetonitrile to obtain compound 3 (163.1 g, yield 82.8%).

[0117] Synthesis example 4: Compound 4 [ka] synthesis Step 1: Add 392.4 g (2 mol) of 1,2,3,4,5,6-heptanehexaol solid to a 2 L three-necked flask and start stirring. Add 784.5 g (6.6 mol) of thionyl chloride dropwise to the three-necked flask, controlling the temperature to approximately 15°C during the dropwise addition process, and allow the reaction to be incubated at 45°C for 4 hours. A large amount of paste-like solid precipitates in the reaction solution. After cooling, slowly add 1 L of deionized water dropwise, quickly stir the reaction system to disperse, filter to obtain the solid, wash the obtained solid by beating it multiple times with deionized water until the pH becomes neutral, and dry the filtered cake under reduced pressure at 60°C to obtain the intermediate product.

[0118] Step 2: Add intermediate product 1 (140 g, 0.4 mol) to a 4 L three-necked flask, add 1000 mL of acetonitrile, add 110 mg of ruthenium trichloride trihydrate catalyst, purge the system with nitrogen gas, cool the system to 20°C, start stirring, and within 1 hour add 1500 g of 20% sodium hypochlorite aqueous solution dropwise to control the reaction temperature to 10-20°C. After the dropwise addition is complete, stir at 10-20°C for 10 minutes, separate the liquid and quench the organic phase with sodium sulfite aqueous solution until the potassium iodide starch test paper no longer turns blue. Separate the liquid and quench the organic layer, crystallize it with acetonitrile to obtain compound 4.

[0119] Synthesis example 5: Compound 5 [ka] synthesis Step 1: Add 484 g (2 mol) of 1,2,3,4,5,6,7,8-octaneoctaol solid to a 2 L three-necked flask and start stirring. Add 1046 g (8.8 mol) of thionyl chloride dropwise to the three-necked flask, controlling the temperature to approximately 15°C during the addition process. After the addition is complete, the reaction is kept at 45°C for 4 hours until a large amount of paste-like solid precipitates in the reaction solution. After cooling, 1 L of deionized water is slowly added dropwise, the reaction system is rapidly stirred to disperse, the solid is filtered, and the obtained solid is washed by beating it multiple times with deionized water until the pH becomes neutral. The filtered cake is dried under reduced pressure at 60°C to obtain the intermediate product.

[0120] Step 2: Add 183.2 g (0.4 mol) of the 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 gas, cool the system to 20°C, start stirring, and within 1 hour add 2000 g of 20% sodium hypochlorite aqueous solution dropwise to control the reaction temperature to 10-20°C. After the dropwise addition is complete, stir for 10 minutes at 10-20°C, separate the liquids, and quench the organic phase with sodium sulfite aqueous solution until the potassium iodide starch test strip no longer turns blue. Separate the liquids again, concentrate the organic layer, and crystallize it with acetonitrile to obtain compound 5.

[0121] Furthermore, for the synthesis method of the compound, refer to Synthesis Example 1, and use the corresponding substrate listed in Table 2 instead of 1,6-dideoxyhexitol.

[0122] [Table 2-1] [Table 2-2] .

[0123] Example 1 Manufacturing of rechargeable batteries: Electrolyte composition: Compound 1 as the first additive has a mass content of 2% in the electrolyte, compounds 3-6 as the second additives have a mass content of 2% in the electrolyte, lithium hexafluoride phosphate (LiPF6) as the electrolyte has a content of 10%, and a mixture of EC+EMC (ethylene carbonate / methyl ethyl carbonate) in a volume ratio of 3:7 is used as the solvent.

[0124] Manufacturing of positive electrode sheets: Lithium iron phosphate (LiFePO4) as the positive electrode active material, acetylene black as the conductive agent, and polyvinylidene fluoride (PVDF) as the binder were dissolved in the solvent N-methylpyrrolidone (NMP) in a weight ratio of 90:5:5, and thoroughly stirred and mixed to obtain a positive electrode paste. Subsequently, the positive electrode paste was uniformly applied to the positive electrode current collector, and a positive electrode sheet was obtained by drying, cold pressing, and cutting.

[0125] Manufacturing of negative electrode sheets: A negative electrode paste was prepared by dissolving graphite (the negative electrode active material), carbon black (the conductive agent), styrene-butadiene rubber (SBR) (the binder), and sodium carboxymethylcellulose (CMC-Na) (the thickener) in deionized water in a weight ratio of 90:4:4:2 and mixing them uniformly. The negative electrode paste was uniformly applied to the copper foil of the negative electrode current collector one or more times, and a negative electrode sheet with a negative electrode film layer was obtained by drying, cold pressing, and cutting. The porosity of the negative electrode film layer was 40%, and the DV50 of the graphite used was 18 μm.

[0126] Separator: A general-purpose polypropylene film was used as the separator.

[0127] Lithium-ion battery assembly: A positive electrode sheet, a separator, and a negative electrode sheet were stacked in order, with the separator positioned between the positive and negative electrode sheets to act as a separator. The assembly was then wound up to obtain an electrode assembly. The electrode assembly was placed in a battery housing, dried, and then the electrolyte was injected. A lithium-ion battery was obtained through processes such as chemical conversion and settling.

[0128] In Examples 1-41 and Comparative Examples 1-4, the substance or amount of the first additive and the substance or amount of the second additive in the electrolyte are all listed in Table 3, and everything else is the same as in Example 1.

[0129] [Table 3-1] [Table 3-2] [Table 3-3] [Table 3-4]

[0130] The porosity of the negative electrode film layer and the Dv50 of the negative electrode material used in Examples 42 to 51 are all listed in Table 4, and all other specifications are the same as in Example 1.

[0131] [Table 4]

[0132] Performance testing: 1. Cycle characteristics test At 25°C, the lithium-ion battery is charged to 3.65V with a constant current of 0.5C, then charging is continued at a constant voltage of 3.65V until the current falls below 0.05C, and then the lithium-ion battery is discharged to 2.5V with a constant current of 0.5C. This constitutes one charge-discharge cycle. This charge-discharge process is repeated, and the number of cycles required after the lithium-ion battery has degraded to 80% is calculated.

[0133] 2. Storage performance test Under conditions of 25°C, each manufactured lithium-ion secondary battery is first charged to 3.65V with a constant current of 0.33C, then further charged to a current of 0.05C with a constant voltage of 3.65V, and then discharged to 2.5V with a constant current of 0.33C. The discharge capacity C0 at this time is the discharge capacity of the lithium-ion secondary battery before high-temperature storage. Next, the lithium-ion secondary battery is charged to 3.65V with a constant current of 0.33C, and then charged to a current of 0.05C with a constant voltage of 3.65V until the lithium-ion battery is fully charged. The battery is left to stand in a 60°C oven for 30 days, then removed and placed in a 25°C environment, and discharged at 0.33C. The discharge capacity is defined as C1. However, the capacity retention rate = (C1 / C0) × 100%.

[0134] 3. Volume expansion coefficient test Under conditions of 25°C, each manufactured lithium-ion secondary battery is first charged to 3.65V with a constant current of 0.33C, then further charged to a current of 0.05C with a constant voltage of 3.65V, and then discharged to 2.5V with a constant current of 0.33C. The discharge capacity at this point is the discharge capacity of the lithium-ion secondary battery before high-temperature storage. Next, the lithium-ion secondary battery is charged to 3.65V with a constant current of 0.33C, and then charged to a current of 0.05C with a constant voltage of 3.65V until the lithium-ion battery is fully charged. The volume of the battery is measured using the drainage method. After that, the lithium-ion secondary batteries are stored at 60°C for 60 days, and after storage, the volume of the lithium-ion secondary batteries is measured in a 25°C environment using the water displacement method. The battery volume expansion rate = (volume after storage / volume before storage - 1)%.

[0135] The test results are listed in Table 5.

[0136] [Table 5-1] [Table 5-2]

[0137] As can be seen from the data comparison in Table 5, even when combined with the same second additive, changing the first additive improves both the battery's cycle characteristics and storage performance, although there are differences in the degree of improvement. Furthermore, comparing the data of Example 1 and Examples 30-41, it was found that the amount of the first and second additives added, as well as their ratio, both affect the improvement in the battery's cycle characteristics and storage performance. In particular, when W1 / W2 was in the range of 0.05-5, the battery's cycle characteristics, storage performance, and volume expansion rate all improved significantly. As can be seen from the data comparison of Examples 42-51, the porosity of the negative electrode film layer and the D of the negative electrode active material improved. V All of the 50s affect improvements in battery cycle characteristics, storage performance, and volume expansion rate.

[0138] While the present application has been described with reference to preferred embodiments, various improvements and substitutions of components with equivalents can be made without departing from the scope of the application. In particular, each technical feature mentioned in each embodiment can be combined in any way, provided that there is no structural inconsistency. The present application is not limited to the specific embodiments disclosed herein and includes all technical solutions included in the claims. [Explanation of Symbols]

[0139] 1 Battery pack 2 Upper cabinet 3 Lower cabinet 4 Battery Modules 5 Secondary battery 51 Housing 52 Electrode Assembly 53. Cap assembly.

Claims

1. A non-aqueous electrolyte containing additives, The additive comprises a first additive and a second additive, the first additive being one or more cyclic sulfate ester compounds having a structure represented by general formula (I), 【Chemistry 1】 However, R １ , R ２ , R ３ and R ４ Each of the following is independently selected from a group having the structure represented by general 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 each of the following is independently an arbitrary integer between 0 and 2. General formula (II) is 【Chemistry 2】 And, R ５ and R ６ Each of these is independently selected from one of the following: a group having the structure represented by the general 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 n3 is any integer between 0 and 2. The second additive comprises one or more of lithium monofluorophosphate, lithium difluorophosphate, lithium tetrafluoroborate, a compound represented by general formula (III), and a fluorosulfonate. 【Transformation 3】 In general formula (III), M is a metal, and the metal includes one or more selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Ba, Al, Fe, Cu, and Ni; Y represents a boron atom or a phosphorus atom; X represents a halogen atom; R represents a C1-C10 alkylene group, a C1-C10 haloalkylene group, a C6-C20 arylene group, or a C6-C20 haloarylene group, and each of the groups representing R is selectively substituted with substituents or heteroatoms; m represents an integer from 1 to 3; n represents an integer from 0 to 4; q represents 0 or 1; and a, b, and c represent natural numbers. The fluorosulfonate is (FSO ３ ), ｙ M ｙ＋ where M ｙ＋ is a metal ion or an organic cation, and the metal ion is Li ＋ , Na ＋ , K ＋ , Rb ＋ , Cs ＋ , Mg ２＋ , Ca ２＋ , Ba ２＋ , Al ３＋ , Fe ２＋ , Cu ２＋ , Fe ３＋ , Ni ２＋ and Ni ３＋ and includes one or more of the group consisting of, a non-aqueous electrolyte.

2. R １ and R ２ It is not a hydrogen atom and also R ３ and R ４ At the same time, it is not a hydrogen atom, Or, R １ , R ２ , R ３ , R ４ , R ５ and R ６ teeth, R １ and R ２ It is simultaneously a hydrogen atom and R ３ and R ４ One of them is a hydrogen atom, and the other is one of the following: a group having the 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 R in the group having the structure represented by general formula (II) ５ and R ６ It also satisfies the condition that it is not a hydrogen atom, Or, R １ , R ２ , R ３ , R ４ , R ５ and R ６ teeth, R ３ and R ４ It is simultaneously a hydrogen atom and R １ and R ２ One of them is a hydrogen atom, and the other is one of the following: a group having the 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 R in the group having the structure represented by general formula (II) ５ and R ６ The non-aqueous electrolyte according to claim 1, which satisfies the condition that it is not a hydrogen atom at the same time.

3. The cyclic sulfate ester compound has the structure represented by general formula (I-1), 【Chemistry 4】 R １ , R ２ , R ３ and R ４ Each of these is independently selected from one of the following: a group having the structure represented by general 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. The general formula (II-1) is 【Transformation 5】 And, R ５ and R ６ The non-aqueous electrolyte according to claim 1 or 2, wherein each of these is independently selected from one of the following: a group having a structure represented by general 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.

4. R １ , R ２ , R ３ , R ４ , R ５ and R ６ Each of these is independently selected from one of the following: a group having the structure represented by general 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. Preferably, R １ , R ２ , R ３ , R ４ , R ５ and R ６ Each of these is independently selected from one of the following: a group having the structure represented by general formula (II-1), a hydrogen atom, a halogen atom, a C1-C3 alkyl group, or a C1-C3 haloalkyl group. Preferably, R １ , R ２ , R ３ , R ４ , R ５ and R ６ Each of these is independently selected from one of the following: a group having the structure represented by general formula (II-1), a hydrogen atom, a F atom, a Cl atom, a Br atom, a methyl group, an ethyl group, a propyl group, and an isopropyl group. Preferably, the group having the structure represented by the general formula (II-1) is 【Transformation 6】 One of the following groups is selected, where X is an F atom, a Cl atom, or a Br atom. Preferably, R １ , R ２ , R ３ and R ４ Each is independent of the others. 【Transformation 7】 X is selected from one of the following: hydrogen atom, F atom, Cl atom, Br atom, methyl group, ethyl group, propyl group, and isopropyl group, and X is an F atom. More preferably, R １ , R ２ , R ３ and R ４ Each is independent of the others. 【Transformation 8】 A non-aqueous electrolyte according to any one of claims 1 to 3, wherein X is selected from one of a hydrogen atom, a methyl group, and an ethyl group, and X is an F atom.

5. The aforementioned cyclic sulfate ester compound is 【Chemistry 9】 A non-aqueous electrolyte according to claim 1, selected from any one or more of the compounds.

6. The non-aqueous electrolyte according to any one of claims 1 to 5, wherein in the general formula (III), the metal comprises one or more selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Ba, Al, Fe, Cu, and Ni, Y represents a boron atom or a phosphorus atom, X represents a halogen atom, R is a C1-C10 alkylene group, a C1-C10 haloalkylene group, a C6-C20 arylene group, or a C6-C20 haloarylene group, and each group representing R is selectively substituted with a substituent or heteroatom, m represents an integer from 1 to 3, n represents an integer from 0 to 4, and q represents 0 or 1.

7. The non-aqueous electrolyte according to any one of claims 1 to 6, wherein the fluorosulfonate comprises one or more of lithium fluorosulfonate, sodium fluorosulfonate, and potassium fluorosulfonate.

8. The mass percentage of the first additive in the non-aqueous electrolyte is W1, preferably W1 is 0.001% to 20%, and more preferably W1 is 0.1% to 5%. and / or, the mass percentage of the second additive in the non-aqueous electrolyte is W2, preferably W2 is 0.001% to 20%, and more preferably W2 is 0.1% to 5%. A non-aqueous electrolyte according to any one of claims 1 to 7, preferably 0.01 ≤ W1 / W2 ≤ 10, and more preferably 0.02 ≤ W1 / W2 ≤ 5.

9. The non-aqueous electrolyte according to any one of claims 1 to 8, wherein the non-aqueous electrolyte further comprises an electrolyte, preferably an alkali metal salt electrolyte, preferably the electrolyte comprises a lithium salt or a sodium salt, preferably the lithium salt comprises one or more selected from the group consisting of lithium hexafluoride phosphate, lithium perchlorate, lithium hexafluoride arsenate, bis(fluorosulfonyl)imide lithium and bis(trifluoromethanesulfonyl)imide lithium, and the sodium salt comprises one or more selected from the group consisting of sodium hexafluoride phosphate, sodium difluoro(oxalato)borate, sodium perchlorate, bis(fluorosulfonyl)imide sodium, bis(trifluoromethanesulfonyl)imide sodium and sodium trifluoromethanesulfonate.

10. The non-aqueous electrolyte further comprises a non-aqueous solvent, preferably one or more selected from the group consisting of cyclic carbonates, linear carbonates, nitrile solvents, ketone solvents, and sulfone solvents, and more preferably the non-aqueous solvent comprises ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, diisopropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl ethyl A non-aqueous electrolyte according to any one of claims 1 to 9, comprising one or more selected from the group consisting of methylformate, methyl acetate, ethyl acetate, n-propyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, tetramethylene sulfone, dimethyl sulfone, methyl ethyl sulfone, diethyl sulfone, tetrahydrofuran, dimethoxyethane, 1,3-dioxolane, acetone, acetonitrile, and n-butyronitrile.

11. The non-aqueous electrolyte according to any one of claims 1 to 10, wherein the additive further comprises one or more selected from the group consisting of sulfate ester compounds, sulfite ester compounds, sultone compounds, disulfonic acid compounds, nitrile compounds, aromatic compounds, isocyanate compounds, phosphazene compounds, cyclic acid anhydride compounds, phosphite ester compounds, phosphate ester compounds, borate ester compounds, and carboxylic acid ester compounds.

12. A secondary battery comprising a positive electrode sheet, an electrolyte, a separator, and a negative electrode sheet, A secondary battery comprising the electrolyte described in any one of claims 1 to 11.

13. The positive electrode sheet includes a positive electrode current collector and a positive electrode film layer provided on one or both sides of the positive electrode current collector, and the lithium ion diffusion coefficient of the positive electrode film layer is Ds, where 10 －１６ cm ２ / s ≤ Ds ≤ 10 －５ cm ２ / s, and preferably, 10 －１３ cm ２ / s ≤ Ds ≤ 10 －９ cm ２ / s. The secondary battery according to claim 12

14. The negative electrode sheet comprises a negative electrode current collector and a negative electrode film layer provided on one or both sides of the negative electrode current collector, wherein the porosity of the negative electrode film layer is 30% to 45%, preferably 37% to 42%. The negative electrode film layer contains a negative electrode active material, preferably the negative electrode active material is D Ｖ 50 is 6 μm or larger, and more preferably the D of the negative electrode active material. Ｖ The secondary battery according to claim 13, wherein 50 is 15 μm to 20 μm.

15. A power consumption device including a secondary battery, The power consumption device includes the secondary battery described in any one of claims 12 to 14.

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