CN109309252B - Electrolyte and electrochemical energy storage device - Google Patents

Electrolyte and electrochemical energy storage device Download PDF

Info

Publication number
CN109309252B
CN109309252B CN201710625272.4A CN201710625272A CN109309252B CN 109309252 B CN109309252 B CN 109309252B CN 201710625272 A CN201710625272 A CN 201710625272A CN 109309252 B CN109309252 B CN 109309252B
Authority
CN
China
Prior art keywords
electrolyte
lithium ion
cyclic
ion battery
energy storage
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201710625272.4A
Other languages
Chinese (zh)
Other versions
CN109309252A (en
Inventor
王小梅
付成华
韩昌隆
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Contemporary Amperex Technology Co Ltd
Original Assignee
Contemporary Amperex Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Contemporary Amperex Technology Co Ltd filed Critical Contemporary Amperex Technology Co Ltd
Priority to CN201710625272.4A priority Critical patent/CN109309252B/en
Publication of CN109309252A publication Critical patent/CN109309252A/en
Application granted granted Critical
Publication of CN109309252B publication Critical patent/CN109309252B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0567—Liquid materials characterised by the additives
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/54—Electrolytes
    • H01G11/58—Liquid electrolytes
    • H01G11/64—Liquid electrolytes characterised by additives
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/054—Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
    • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/54—Electrolytes
    • H01G11/56—Solid electrolytes, e.g. gels; Additives therein
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0565—Polymeric materials, e.g. gel-type or solid-type
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Abstract

The application provides an electrolyte and an electrochemical energy storage device. The electrolyte includes an electrolyte salt and an additive. The additives include sulfonate cyclic quaternary ammonium salts and cyclic disulfonate compounds. When the electrochemical energy storage device is formed, the cyclic quaternary ammonium sulfonate and the cyclic disulfonate compound can form a layer of compact and uniform passivation film with high ion conductivity on the surfaces of the positive electrode and the negative electrode, so that continuous oxidation and reduction reactions between electrolyte and the positive electrode and between electrolyte and the negative electrode can be avoided, and the electrochemical energy storage device has good rate capability, low-temperature discharge performance and high-temperature storage performance.

Description

Electrolyte and electrochemical energy storage device
Technical Field
The application relates to the field of energy storage devices, in particular to electrolyte and an electrochemical energy storage device.
Background
With the increasing exhaustion of fossil energy and the increasing pressure of environmental pollution, the automobile industry urgently needs a novel energy source to provide drive for the fossil energy source, and the lithium ion battery is distinguished due to the characteristics of high energy density, no memory effect, high working voltage and the like, so that the lithium ion battery is currently the preferred scheme of a power supply of a new energy automobile. However, with the expansion of market demand of electronic products and the development of power and energy storage devices, people have continuously increased requirements on lithium ion batteries, and it is urgent to develop lithium ion batteries having high energy density and satisfying rapid charging and discharging. Currently, effective methods are to increase the voltage, the compaction density, and select a suitable electrolyte for the electrode active material.
When the energy density of the lithium ion battery is increased (such as increasing the battery voltage) in order to meet the use requirements of products, the uncertainty of the safety of the lithium ion battery is increased. For example, when a lithium ion battery is used at a high temperature, the electrolyte undergoes severe oxidation and reduction reactions at the positive and negative electrodes of the lithium ion battery, a large amount of gas is generated, and the lithium ion battery may swell. This not only can lead to lithium ion battery to damage, also can lead to the damage of the equipment that uses this lithium ion battery simultaneously, and serious time leads to the inside short circuit that takes place of lithium ion battery or lithium ion battery packing bursting to make flammable electrolyte reveal because of lithium ion battery inflation deformation, has the risk of causing incident such as conflagration. There is therefore a need for effective techniques to address the decomposition of electrolytes and the gassing of lithium ion batteries.
In practical use, in order to solve the decomposition of the electrolyte and the gas expansion of the lithium ion battery, some additives capable of forming passivation films on the surfaces of the positive electrode and the negative electrode to effectively isolate the electrolyte from the reaction of the positive electrode and the negative electrode are often added, but the passivation films generated by the reaction of the additives are usually too high in impedance, so that the normal de-intercalation process of lithium ions is hindered, and the dynamic performance of the lithium ion battery is seriously influenced. Therefore, it is important to develop an electrolyte having good high-temperature storage performance at high voltage while maintaining good dynamic characteristics.
Disclosure of Invention
In view of the problems in the background art, it is an object of the present application to provide an electrolyte and an electrochemical energy storage device having good rate capability, low-temperature discharge capability and high-temperature storage capability.
In order to achieve the above objects, in one aspect of the present application, there is provided an electrolyte, an electrolyte salt, and an additive. The additives include sulfonate cyclic quaternary ammonium salts and cyclic disulfonate compounds.
In another aspect of the present application, an electrochemical energy storage device is provided that includes an electrolyte as described in one aspect of the present application.
Compared with the prior art, the beneficial effects of this application do:
the electrolyte additive comprises the cyclic quaternary ammonium salt of sulfonate and a cyclic disulfonate compound, and when the electrochemical energy storage device is formed, the cyclic quaternary ammonium salt of sulfonate and the cyclic disulfonate compound can form a layer of dense and uniform passivation film with higher ion conductivity on the surfaces of the positive electrode and the negative electrode, so that continuous oxidation and reduction reactions between the electrolyte and the positive electrode and between the electrolyte and the negative electrode can be avoided, and the electrochemical energy storage device has good rate capability, low-temperature discharge capability and high-temperature storage capability.
Detailed Description
The electrolyte and electrochemical energy storage device according to the present application are described in detail below.
First, an electrolytic solution according to the first aspect of the present application is explained.
The electrolyte according to the first aspect of the present application includes an electrolyte salt and an additive. The additives include sulfonate cyclic quaternary ammonium salts and cyclic disulfonate compounds.
In the electrolyte according to the first aspect of the present application, the cyclic quaternary ammonium sulfonate salt is selected from one or more compounds represented by formula 1; in formula 1, R11One selected from the group consisting of-CN, substituted or unsubstituted C1-12 alkyl, substituted or unsubstituted C2-12 alkenyl, substituted or unsubstituted C2-12 alkynyl, substituted or unsubstituted C1-12 alkoxy, and substituted or unsubstituted C1-12 acyloxy; r12One selected from the group consisting of substituted or unsubstituted C1-12 alkylene, substituted or unsubstituted C2-12 alkenylene, substituted or unsubstituted C2-12 alkynylene, and substituted or unsubstituted C1-12 alkyleneacyl; r13One selected from substituted or unsubstituted C1-12 alkyl, substituted or unsubstituted C2-12 alkenyl, substituted or unsubstituted C2-12 alkynyl, substituted or unsubstituted C1-12 alkoxy, substituted or unsubstituted C1-12 acyloxy, substituted or unsubstituted C6-22 aryl and substituted or unsubstituted C5-22 heteroaryl; r14Selected from substituted or unsubstituted C1-3 alkylene; the substituent is selected from one or more of-CN and halogen atom.
Figure BDA0001362671770000031
In the formula 1, the first and second groups,
Figure BDA0001362671770000032
it is meant an anion, and it is meant,
Figure BDA0001362671770000033
is selected from F-、NO3 -、SO4 2-、PF6 -、PF4 -、AsF6 -、
Figure BDA0001362671770000034
Figure BDA0001362671770000035
One kind of (1).
In the electrolyte according to the first aspect of the present application, the cyclic disulfonate compound is selected from one or more compounds represented by formula 2; in formula 2, R21One selected from linear or branched C1-5 alkylene or halogenated alkylene; r22The material is selected from one of sulfinyl, carbonyl, linear or branched C1-5 alkylene or halogenated alkylene.
Figure BDA0001362671770000036
In the electrolyte according to the first aspect of the present application, the electrolyte may be a liquid electrolyte, a solid polymer electrolyte, or a gel polymer electrolyte. Since the liquid electrolyte has a similar action mechanism to that of the solid polymer electrolyte and the gel polymer electrolyte, the liquid electrolyte is merely exemplified in the present application.
In the electrolyte according to the first aspect of the present application, when the cyclic quaternary ammonium sulfonate and the cyclic disulfonate compound are used in combination, a compact and firm passivation film can be formed on the surfaces of the positive electrode and the negative electrode, and the contact between the positive electrode and the negative electrode and the electrolyte can be reduced, so that the continuous oxidation and reduction reactions of the electrolyte on the surfaces of the positive electrode and the negative electrode can be avoided, the decomposition of the electrolyte and the increase of the internal resistance of the electrochemical energy storage device can be further reduced, and the rate capability, the low-temperature discharge performance and the high-temperature storage performance of the electrochemical energy storage device. This is because the cyclic quaternary ammonium sulfonate salt has a specific structure of a cationic group (that is, the cationic group portion of the cyclic quaternary ammonium sulfonate salt is positively charged by a unit)The charged cyclic quaternary ammonium head and the functional sulfonate tail are connected through an intermediate organic carbon chain), so that the cyclic quaternary ammonium head with unit positive charge can drive the whole cationic group to actively approach the negative electrode to be preferentially reduced, decomposed and broken when the reduction potential is 1.5V, and the functional sulfonate tail is released, and a layer of metal alkyl sulfonate (RSO) can be preferentially established on the surface of the negative electrode3X) and the like, and the metal alkyl sulfonate has high intrinsic ionic conductivity and high thermal stability, so that the SEI film formed on the surface of the negative electrode has the characteristics of compact and uniform internal structure, low impedance, excellent high-temperature performance and the like, and can improve the internal resistance and high-temperature storage performance of the electrochemical energy storage device. When the cyclic disulfonate compound is formed, a passivation film with a compact and uniform structure, low impedance and excellent high-temperature performance can be formed on the surface of the positive electrode, the dynamic performance of the electrochemical energy storage device can be further improved, the electrochemical energy storage device has better rate performance and low-temperature discharge performance, and the high-temperature storage performance of the electrochemical energy storage device can be further improved.
In the electrolyte according to the first aspect of the present application, in formula 1, preferably, R11One selected from substituted or unsubstituted C1-6 alkyl or halogenated alkyl, R12One selected from substituted or unsubstituted C1-12 alkylene, R13One selected from substituted or unsubstituted C1-6 alkyl or halogenated alkyl, R14One selected from substituted or unsubstituted C1-2 alkylene.
In the electrolyte according to the first aspect of the present application, the cationic group of the cyclic quaternary ammonium sulfonate salt may be selected from
Figure BDA0001362671770000041
Figure BDA0001362671770000051
Figure BDA0001362671770000052
One kind of (1).
In the electrolyte according to the first aspect of the present application, specifically, the cyclic quaternary ammonium sulfonate salt may be selected from one or more of the following compounds; the present application is not so limited;
Figure BDA0001362671770000061
in the electrolyte according to the first aspect of the present application, specifically, the cyclic disulfonate compound may be selected from one or more of the following compounds; the present application is not so limited;
Figure BDA0001362671770000062
Figure BDA0001362671770000071
in the electrolyte according to the first aspect of the present application, when the content of the cyclic quaternary ammonium sulfonate is too low, the formed positive and negative passive films are not sufficient to prevent the electrolyte from further reacting, and the performance of the electrochemical energy storage device is not significantly improved; when the content is too high, the impedance of the electrochemical energy storage device on the positive electrode and the negative electrode is increased, and the performance of the electrochemical energy storage device is deteriorated. Preferably, the content of the cyclic quaternary ammonium sulfonate salt is 0.05-10% of the total mass of the electrolyte. More preferably, the content of the cyclic quaternary ammonium sulfonate salt is 0.1 to 5 percent of the total mass of the electrolyte.
In the electrolyte according to the first aspect of the present application, when the content of the cyclic disulfonate compound is too small, the resistance of the positive and negative passivation films is slightly reduced; when the content is too high, too much cyclic disulfonate compound is easily crystallized and deposited in the electrolyte, and at the same time, the performance of the electrochemical energy storage device may be deteriorated due to its poor high-temperature stability. Preferably, the content of the cyclic disulfonate compound is 0.1 to 5% of the total mass of the electrolyte. More preferably, the content of the cyclic disulfonate compound is 0.5% to 2% of the total mass of the electrolyte.
In the electrolyte according to the first aspect of the present application, the electrolyte further includes an organic solvent, and the type of the organic solvent is not particularly limited and may be selected according to actual needs. Preferably, a non-aqueous organic solvent is used. The non-aqueous organic solvent may include any kind of carbonate and/or carboxylate. The carbonate may include a mixture of cyclic carbonates as well as chain carbonates. The non-aqueous organic solvent may further include a halogenated compound of a carbonate. Specifically, the organic solvent may be one or more selected from ethylene carbonate, propylene carbonate, butylene carbonate, pentylene carbonate, fluoroethylene carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methylethyl carbonate, methyl formate, ethyl acetate, propyl propionate, ethyl propionate, γ -butyrolactone, and tetrahydrofuran.
In the electrolyte according to the first aspect of the present application, the concentration of the electrolyte salt is not particularly limited, and may be selected according to actual needs. Specifically, the content of the electrolyte salt is 6% to 25% of the total mass of the electrolyte solution. Preferably, the content of the electrolyte salt is 6% to 20% of the total mass of the electrolyte solution. Further preferably, the content of the electrolyte salt is 10% to 15% of the total mass of the electrolytic solution.
Next, an electrochemical energy storage device according to the second aspect of the present application will be described.
An electrochemical energy storage device according to the second aspect of the present application comprises an electrolyte according to the first aspect of the present application.
In the electrochemical energy storage device according to the second aspect of the present application, the electrochemical energy storage device further comprises a positive electrode sheet, a negative electrode sheet, a separator, a packaging case, and the like.
It should be noted that the electrochemical energy storage device may be a lithium ion battery, a sodium ion battery, a zinc ion battery, a metal lithium battery, an all solid state sodium battery, or a super capacitor. In the embodiments of the present application, only the embodiment in which the electrochemical energy storage device is a lithium ion battery is shown, but the present application is not limited thereto.
In the lithium ion battery, the positive plate comprises a positive current collector and a positive diaphragm arranged on the positive current collector. The positive electrode diaphragm comprises a positive electrode active material, and the positive electrode diaphragm also comprises a conductive agent and a binder. The positive active material may be selected from lithium cobaltate (LiCoO)2) Lithium nickelate (LiNiO)2) Spinel type lithium manganate (LiMn)2O4) Olivine type LiMPO4Ternary material LiaNixAyB(1-x-y)O2One or more of them. Wherein the olivine type LiMPO4In the formula, M is selected from one or more of Co, Ni, Fe, Mn and V; in the ternary material LiaNixAyB(1-x-y)O2Wherein A, B is independently selected from one of Co, Al and Mn, A and B are different, a is more than or equal to 0.95 and less than or equal to 1.2, 0<x<1，0<y<1, and x + y<1. The kind of the conductive agent and the binder is not particularly limited and may be selected according to actual requirements.
In the lithium ion battery, the negative electrode sheet comprises a negative electrode current collector and a negative electrode film sheet arranged on the negative electrode current collector. The negative electrode diaphragm comprises a negative electrode active material, and the negative electrode diaphragm also comprises a conductive agent and a binder. The negative active material may be selected from the group consisting of Li/Li at a voltage < 2V (vs+) A material that can intercalate lithium, and specifically, the negative active material may be selected from natural graphite, artificial graphite, mesophase micro carbon spheres (abbreviated as MCMB), hard carbon, soft carbon, silicon-carbon composite, Li-Sn alloy, Li-Sn-O alloy, Sn, SnO2Spinel-structured lithiated TiO2-Li4Ti5O12And one or more of Li-Al alloy. The kind of the conductive agent and the binder is not particularly limited and may be selected according to actual requirements. The negative electrode sheet may also be a metallic lithium sheet.
In the lithium ion battery, the electrolyte salt is lithium salt, and the specific type of the lithium salt is not influencedAnd (4) limiting. Specifically, the lithium salt includes at least LiPF6The lithium salt may further include LiBF4、LiFSI、LiTFSI、LiClO4、LiAsF6、LiBOB、LiDFOB、LiPO2F2、LiTFOP、LiN(SO2RF)2、LiN(SO2F)(SO2RF), wherein RF ═ CnF2n+1It represents a saturated perfluoroalkyl group, and n is an integer of 1 to 10.
In the lithium ion battery, the kind of the separator is not particularly limited and may be selected according to actual needs, and specifically, the separator may be selected from a polyethylene film, a polypropylene film, a polyvinylidene fluoride film, and a multi-layer composite film thereof.
The present application is further illustrated below with reference to examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present application. In the embodiments, only the case where the electrochemical energy storage device is a lithium ion battery is shown, but the present application is not limited thereto.
In the following examples, reagents, materials and instruments used are commercially available unless otherwise specified, and the cyclic quaternary ammonium sulfonate salt used is described in CN105845981A published on 8/10 2016.
The lithium ion batteries of examples 1 to 11 and comparative examples 1 to 7 were prepared as follows:
(1) preparation of positive plate
The positive electrode active material lithium cobaltate (LiCoO)2) The conductive agent acetylene black and the adhesive polyvinylidene fluoride according to the mass ratio of LiCoO2Mixing acetylene black and polyvinylidene fluoride in a ratio of 98:1:1, adding solvent N-methyl pyrrolidone, and stirring under the action of a vacuum stirrer until the system becomes uniform and transparent to obtain anode slurry; uniformly coating the positive electrode slurry on a positive electrode current collector aluminum foil with the thickness of 12 mu m; and (3) airing the aluminum foil at room temperature, transferring the aluminum foil to a 120 ℃ oven for drying for 1h, and then performing cold pressing and slitting to obtain the positive plate.
(2) Preparation of negative plate
Mixing the negative active material artificial graphite, the thickener sodium carboxymethyl cellulose (CMC) and the binder styrene-butadiene rubber emulsion according to the mass ratio of 98:1:1, adding deionized water, and obtaining negative slurry under the action of a vacuum stirrer; uniformly coating the negative electrode slurry on a negative electrode current collector copper foil with the thickness of 8 mu m; and (3) airing the copper foil at room temperature, transferring the copper foil to a 120 ℃ oven for drying for 1h, and then performing cold pressing and slitting to obtain the negative plate.
(3) Preparation of the electrolyte
At water content<In a 10ppm argon atmosphere glove box, Ethylene Carbonate (EC), Propylene Carbonate (PC), and diethyl carbonate (DEC) were mixed at a volume ratio of EC: PC: DEC: 1:1, and then a fully dried lithium salt LiPF was added6Dissolving the mixture in a mixed organic solvent, adding a cyclic quaternary ammonium sulfonate and a cyclic disulfonate compound, and uniformly mixing to obtain the electrolyte. Wherein, LiPF6The content of (b) was 12.5% of the total mass of the electrolyte. Specific kinds and contents of the sulfonate cyclic quaternary ammonium salt and cyclic disulfonate compound used in the electrolyte are shown in table 1. In table 1, the contents of the sulfonate cyclic quaternary ammonium salt and the cyclic disulfonate compound are mass percentages calculated based on the total mass of the electrolyte.
(4) Preparation of the separator
A16 μm thick polypropylene separator (model A273 from Celgard) was used.
(5) Preparation of lithium ion battery
Stacking the positive plate, the isolating film and the negative plate in sequence to enable the isolating film to be positioned between the positive plate and the negative plate to play an isolating role, and then winding to obtain a bare cell; placing the bare cell in an outer packaging shell, injecting the prepared electrolyte into the dried bare cell, and performing vacuum packaging, standing, formation, shaping and other processes to obtain the lithium ion battery.
TABLE 1 parameters of examples 1 to 11 and comparative examples 1 to 7
Figure BDA0001362671770000111
Next, a test procedure of the lithium ion battery is explained.
(1) Low-temperature discharge performance test of lithium ion battery
Charging the lithium ion battery at a constant current of 0.5 ℃ to a voltage of 4.4V at 25 ℃, then charging at a constant voltage of 4.4V to a current of less than or equal to 0.05C, standing for 10min, discharging at a constant current of 0.5C to a cut-off voltage of 3.0V, testing the discharge capacity of the lithium ion battery at the moment, and marking as C0; and then charging the lithium ion battery with a constant current of 0.5C until the voltage is 4.4V, then charging with a constant voltage of 4.4V until the current is less than or equal to 0.05C, standing for 10min, then placing the lithium ion battery in a constant temperature box at-10 ℃ for standing for 2h, then discharging with a constant current of 0.5C until the cut-off voltage is 3.0V, and testing the discharge capacity of the lithium ion battery at the moment and marking as C1. Each group was tested for 15 lithium ion batteries and the average was taken.
The discharge capacity retention (%) of the lithium ion battery stored at-10 ℃ for 2 hours was (C1/C0) × 100%.
(2) Rate capability test of lithium ion battery
Charging the lithium ion battery at a constant current of 1C (nominal capacity) to a voltage of 4.4V at 25 ℃, then charging the lithium ion battery at a constant voltage of 4.4V to a current of less than or equal to 0.05C, standing for 5min, discharging the lithium ion battery at a constant current of 0.2C to a cut-off voltage of 3V, and testing the discharge capacity of the lithium ion battery at the moment and marking the discharge capacity as D0. And then charging with a constant current of 1C until the voltage is 4.4V, then charging with a constant voltage of 4.4V until the current is less than or equal to 0.05C, finally discharging with a constant current of 5C until the cut-off voltage is 3V, and testing the discharge capacity of the lithium ion battery at the moment and marking as D1. Each group was tested for 15 lithium ion batteries and the average was taken.
Rate performance (%) of the lithium ion battery 5C/0.2C was (D1/D0) × 100%.
(3) High temperature storage performance testing of lithium ion batteries
Charging the lithium ion battery at a constant current of 1C to a voltage of 4.4V at 25 ℃, then charging at a constant voltage of 4.4V to a current of less than 0.05C, and then discharging at a constant current of 0.5C to a voltage of 3.0V; and then charging with a constant current of 1C until the voltage is 4.4V, then charging with a constant voltage of 4.4V until the current is less than 0.05C, and testing the discharge capacity of the lithium ion battery at the moment and marking as Q0. Then storing the lithium ion battery at 60 ℃ for 30 days, and after the storage is finished, discharging at a constant current of 1C until the voltage is 3.0V; and then charging with a constant current of 1C until the voltage is 4.4V, then charging with a constant voltage of 4.4V until the current is less than 0.05C, and then discharging with a constant current of 0.5C until the voltage is 3.0V, and testing the discharge capacity of the lithium ion battery at the moment and marking as Q1. Each group was tested for 15 lithium ion batteries and the average was taken.
Capacity retention (%) of the lithium ion battery stored at 60 ℃ for 30 days is [ Q1/Q0] × 100%.
TABLE 2 Performance test results of examples 1 to 11 and comparative examples 1 to 7
Figure BDA0001362671770000131
From the analysis of the related data in table 2, it can be known that the lithium ion battery has better rate capability, low-temperature discharge capability and high-temperature storage capability under the combined action of the cyclic quaternary ammonium sulfonate and the cyclic disulfonate compound.
Analysis in comparative examples 1-3 shows that the cyclic quaternary ammonium sulfonate and cyclic disulfonate compound are not added in comparative example 1, and the rate performance, the low-temperature discharge performance and the high-temperature storage performance of the lithium ion battery are poor; when the electrolyte only contains the cyclic quaternary ammonium salt sulfonate (comparative example 2), the high-temperature storage performance of the lithium ion battery can be obviously improved on the premise of not influencing the rate capability and the low-temperature discharge performance of the lithium ion battery; when only the cyclic disulfonate compound was contained in the electrolyte (comparative example 3), the rate performance and low-temperature discharge performance of the lithium ion battery were significantly improved, while the improvement in high-temperature storage performance was relatively weak.
Analysis in examples 1-11 and comparative examples 4-7 shows that the cyclic quaternary ammonium sulfonate and the cyclic disulfonate compound are added to the electrolyte at the same time, and the lithium ion battery has good rate capability, low-temperature discharge capability and high-temperature storage capability. The sulfonic ester cyclic quaternary ammonium salt and the cyclic disulfonate compound can form a layer of dense and uniform passivation film with high ion conductivity on the surfaces of the positive electrode and the negative electrode, so that continuous oxidation and reduction reactions between the electrolyte and the positive electrode and the negative electrode can be avoided, and the lithium ion battery has good rate capability, low-temperature discharge performance and high-temperature storage performance. Meanwhile, it can be understood that the specific types and the dosage changes of the cyclic quaternary ammonium sulfonate and the cyclic disulfonate compound inevitably directly affect the performance of the electrolyte, thereby affecting the improvement effect on the performance of the lithium ion battery.
In comparative example 4, the content of the cyclic quaternary ammonium sulfonate salt was insufficient, and the high-temperature storage performance of the lithium ion battery was not significantly improved. In examples 1 to 5, with the increase of the content of the cyclic quaternary ammonium sulfonate, the high-temperature storage capacity retention rate of the lithium ion battery was improved without the significant deterioration tendency of the rate performance and the low-temperature discharge performance of the lithium ion battery. When the content of the cyclic quaternary ammonium sulfonate salt is excessively high, such as in comparative example 5, the rate performance, low-temperature discharge performance, and high-temperature storage performance of the lithium ion battery are all remarkably deteriorated.
In comparative example 6, the content of the cyclic disulfonate compound was insufficient, and the rate performance and low-temperature discharge performance of the lithium ion battery were improved weakly. In examples 6 to 9, as the content of the cyclic disulfonate compound increases, the rate capability and the low-temperature discharge capacity retention rate of the lithium ion battery are improved without a significant deterioration tendency of the high-temperature storage performance of the lithium ion battery. When the content of the cyclic disulfonate compound is excessively high, for example, in comparative example 7, the high-temperature storage capacity retention rate of the lithium ion battery is deteriorated due to the decrease in the conductivity of the electrolyte, and on the one hand, the cyclic disulfonate compound in excess may be deposited in the electrolyte and fail to function, and on the other hand, the cyclic disulfonate compound itself is unstable and easily decomposed, thereby deteriorating the rate capability and low-temperature discharge performance of the lithium ion battery.
Therefore, the performance of the lithium ion battery is not improved to the whole due to too little or too much content of the cyclic quaternary ammonium sulfonate and cyclic disulfonate compound, but the rate performance, the low-temperature discharge performance and the high-temperature storage performance of the lithium ion battery can be improved to a certain extent in some use requirements which are relatively low or less.
Those skilled in the art to which the present application pertains can also make appropriate changes and modifications to the above-described embodiments, based on the disclosure of the above description. Therefore, the present application is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present application should fall within the scope of the claims of the present application.

Claims (15)

1. An electrolyte, comprising:
an electrolyte salt; and
an additive;
it is characterized in that the preparation method is characterized in that,
the additive comprises a sulfonate cyclic quaternary ammonium salt and a cyclic disulfonate compound;
the cyclic quaternary ammonium sulfonate salt is:
Figure FDA0002837373650000011
the cyclic disulfonate compound is:
Figure FDA0002837373650000012
2. the electrolyte of claim 1, wherein the additive further comprises an additive A, and the additive A is selected from one or more of the following compounds:
Figure FDA0002837373650000013
Figure FDA0002837373650000021
3. the electrolyte of claim 1, wherein the additive further comprises an additive B, wherein the additive B is selected from one or more of the following compounds;
Figure FDA0002837373650000022
Figure FDA0002837373650000031
4. the electrolyte of claim 1,
the content of the cyclic quaternary ammonium sulfonate is 0.05-10% of the total mass of the electrolyte;
the content of the cyclic disulfonate compound is 0.1-5% of the total mass of the electrolyte.
5. The electrolyte of claim 4,
the content of the cyclic disulfonate compound is 0.5-2% of the total mass of the electrolyte.
6. The electrolyte of claim 4,
the content of the cyclic quaternary ammonium sulfonate is 0.1-5% of the total mass of the electrolyte.
7. The electrolyte of claim 2,
the content of the additive A is 0.05-10% of the total mass of the electrolyte.
8. The electrolyte of claim 3, wherein the additive B is present in an amount of 0.1 to 5% by weight of the total electrolyte.
9. The electrolyte of claim 7, wherein the additive A is present in an amount of 0.1% to 5% by weight of the total electrolyte.
10. The electrolyte of claim 8, wherein the additive B is present in an amount of 0.5% to 2% by weight of the total electrolyte.
11. The electrolyte of claim 1, wherein the electrolyte salt is present in an amount of 6% to 25% by weight of the total electrolyte.
12. The electrolyte of claim 11, wherein the electrolyte salt is present in an amount of 6% to 20% by weight of the total electrolyte.
13. The electrolyte of claim 12, wherein the electrolyte salt is present in an amount of 10% to 15% by weight based on the total weight of the electrolyte.
14. The electrolyte of claim 1, wherein the electrolyte is a liquid electrolyte, a solid polymer electrolyte, or a gel polymer electrolyte.
15. An electrochemical energy storage device comprising an electrolyte according to any one of claims 1 to 14.
CN201710625272.4A 2017-07-27 2017-07-27 Electrolyte and electrochemical energy storage device Active CN109309252B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201710625272.4A CN109309252B (en) 2017-07-27 2017-07-27 Electrolyte and electrochemical energy storage device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201710625272.4A CN109309252B (en) 2017-07-27 2017-07-27 Electrolyte and electrochemical energy storage device

Publications (2)

Publication Number Publication Date
CN109309252A CN109309252A (en) 2019-02-05
CN109309252B true CN109309252B (en) 2021-05-04

Family

ID=65202317

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201710625272.4A Active CN109309252B (en) 2017-07-27 2017-07-27 Electrolyte and electrochemical energy storage device

Country Status (1)

Country Link
CN (1) CN109309252B (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102593508A (en) * 2012-02-22 2012-07-18 深圳新宙邦科技股份有限公司 Lithium ion battery
CN105186032A (en) * 2015-10-19 2015-12-23 东莞市凯欣电池材料有限公司 High-voltage lithium-ion battery electrolyte and lithium-ion battery using high-voltage lithium-ion battery electrolyte
CN106099184A (en) * 2016-06-28 2016-11-09 宁德新能源科技有限公司 A kind of electrolyte and use the lithium ion battery of this electrolyte
JP2016213103A (en) * 2015-05-12 2016-12-15 Ｎｅｃエナジーデバイス株式会社 Lithium ion secondary battery and method for manufacturing the same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102593508A (en) * 2012-02-22 2012-07-18 深圳新宙邦科技股份有限公司 Lithium ion battery
JP2016213103A (en) * 2015-05-12 2016-12-15 Ｎｅｃエナジーデバイス株式会社 Lithium ion secondary battery and method for manufacturing the same
CN105186032A (en) * 2015-10-19 2015-12-23 东莞市凯欣电池材料有限公司 High-voltage lithium-ion battery electrolyte and lithium-ion battery using high-voltage lithium-ion battery electrolyte
CN106099184A (en) * 2016-06-28 2016-11-09 宁德新能源科技有限公司 A kind of electrolyte and use the lithium ion battery of this electrolyte

Also Published As

Publication number Publication date
CN109309252A (en) 2019-02-05

Similar Documents

Publication Publication Date Title
CN112349962B (en) Lithium ion battery
CN109309226B (en) Electrochemical energy storage device
WO2020216052A1 (en) Electrolyte solution, lithium-ion battery, and device containing lithium-ion battery
CN108242556B (en) Electrolyte solution and secondary battery
CN108242557B (en) Electrolyte solution and secondary battery
US10797348B2 (en) Electrolyte and lithium-ion battery
CN111525190B (en) Electrolyte and lithium ion battery
CN106997959B (en) Additive, non-aqueous electrolyte and lithium ion battery
CN112467209A (en) High-voltage lithium ion battery with high and low temperature performance
US10686221B2 (en) Electrolyte and electrochemical energy storage device
CN109309255A (en) Electrolyte and electrochemical energy storage device
CN108695487B (en) Positive plate and energy storage device
CN109309249B (en) Electrolyte and electrochemical energy storage device
US20240154115A1 (en) Lithium-ion Battery
US20220216515A1 (en) Electrolyte and electrochemical apparatus
CN109309208B (en) Positive electrode slurry, positive plate and electrochemical energy storage device
CN109309254B (en) Electrolyte and electrochemical energy storage device
CN109309253A (en) Electrolyte and electrochemical energy storage device
CN109994768A (en) Electrolyte solution and secondary battery
CN109309252B (en) Electrolyte and electrochemical energy storage device
CN112838269A (en) Electrolyte solution, electrochemical device and electronic apparatus including the same
KR101349942B1 (en) Polymer electrolyte for lithium secondary battery and lithium secondary battery comprising the same
CN109309250A (en) Electrolyte and secondary lithium battery
US11967674B2 (en) Electrolyte and electrochemical device
CN110649317B (en) Silicon-based lithium ion battery electrolyte and lithium ion secondary battery

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant