CN112117490B - Lithium ion battery electrolyte and lithium ion secondary battery - Google Patents

Lithium ion battery electrolyte and lithium ion secondary battery Download PDF

Info

Publication number
CN112117490B
CN112117490B CN201910535886.2A CN201910535886A CN112117490B CN 112117490 B CN112117490 B CN 112117490B CN 201910535886 A CN201910535886 A CN 201910535886A CN 112117490 B CN112117490 B CN 112117490B
Authority
CN
China
Prior art keywords
electrolyte
substituted
unsubstituted
atom
formula
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
CN201910535886.2A
Other languages
Chinese (zh)
Other versions
CN112117490A (en
Inventor
史松君
林明峰
邢柯
胡贤飞
来佑磊
金海族
李志强
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 CN201910535886.2A priority Critical patent/CN112117490B/en
Publication of CN112117490A publication Critical patent/CN112117490A/en
Application granted granted Critical
Publication of CN112117490B publication Critical patent/CN112117490B/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
    • 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
    • H01M10/42—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
    • 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

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Inorganic Chemistry (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Secondary Cells (AREA)

Abstract

The inventors provide a lithium ion secondary battery containing a positive electrode active material of manganese element and an electrolyte thereof, including: a lithium salt; a non-aqueous organic solvent; a compound of the formula I,
Figure DDA0002101157670000011
a compound of the formula II,
Figure DDA0002101157670000012
a compound of the formula (III),

Description

Lithium ion battery electrolyte and lithium ion secondary battery
Technical Field
The present invention relates to an electrolyte for a lithium ion battery and a lithium ion secondary battery.
Background
In recent years, portable electronic products such as cameras, digital video cameras, cellular phones, notebook computers, and the like have been widely used in daily life. Among them, the reduction in size, weight and service life are trends and requirements for the development of portable electronic products. Therefore, development of power supply products compatible with portable electronic products, particularly development of lightweight secondary batteries capable of providing high energy density and long cycle life, is an urgent requirement for development of the battery industry.
The manganese-containing material represented by lithium manganate has the advantages of abundant natural resources, low cost, high working voltage platform, low toxicity to the environment and the like, but has poor cycle performance and high-temperature stability mainly because the manganese is easy to dissolve out of the manganese-containing material, especially under acidic conditions. The existing electrolyte mainly uses lithium hexafluorophosphate as a lithium salt, the lithium hexafluorophosphate is easy to generate hydrogen fluoride in the circulation and storage processes, the hydrogen fluoride catalyzes manganese-containing compounds such as lithium manganate to generate manganese dissolution, so that the anode is damaged in large quantity, and dissolved manganese elements can be deposited on the cathode to further damage the anode. The SEI film of the negative electrode is damaged, and the cycle performance of the lithium ion battery is reduced.
Disclosure of Invention
In view of the problems in the background art, the present invention provides an electrolyte for a lithium ion battery and a lithium ion secondary battery to improve the problem of manganese elution of a manganese-containing positive electrode.
To achieve the above object, in a first aspect of the present invention, the inventors provide a lithium ion battery electrolyte comprising:
a lithium salt;
a non-aqueous organic solvent;
a compound of the formula I,
Figure BDA0002101157660000021
wherein R is1-R6Each independently selected from a halogen atom, a substituted or unsubstituted C1～20Alkyl, substituted or unsubstituted C2～20Alkenyl of, substituted or unsubstituted C6～26Aryl, substituted or unsubstituted C1～20Alkoxy, substituted or unsubstituted C6～26One of the aryloxy groups of (a); wherein the halogen atom is a fluorine atom, a chlorine atom or a bromine atom;
a compound of the formula II,
Figure BDA0002101157660000022
wherein R is21、R22、R23Each independently selected from a hydrogen atom, a substituted or unsubstituted C1～20Alkyl, substituted or unsubstituted C2～20Alkenyl, substituted or unsubstituted C2～20Alkynyl, substituted or unsubstituted C6～26One of aryl and substituted or unsubstituted phenyl;
a compound of the formula (III),
Figure BDA0002101157660000023
wherein R is11、R12、R13、R14、R15、R16Each independently selected from substituted or unsubstituted C1～10An alkyl group of (A), a substituted or unsubstituted carbon atom number of C6～26One of aryl groups of (1).
In a second aspect of the present invention, the present invention provides a lithium ion secondary battery comprising:
a positive electrode containing a positive electrode active material containing a manganese element;
an anode comprising an anode active material and
the electrolyte according to the first aspect of the present invention.
Compared with the prior art, the lithium ion battery electrolyte provided by the invention has the following beneficial effects:
the deacidification additive shown in the formula I can effectively react with water and hydrogen fluoride generated in the operation process of the lithium ion secondary battery to generate silicon fluoride products to cover the surface of the cathode and the anode and protect the cathode and the anode; the cathode coordination additive shown in the formula II can be coordinated with a cathode by utilizing an electron-deficient structure of a borate compound, so that the effects of protecting the cathode and inhibiting manganese dissolution are achieved; the film forming additive shown in the formula III can reduce manganese dissolution, and the anode film forming can reduce the damage of manganese to the cathode. The three are mutually matched and act together, so that the formed films of the anode and the cathode are more uniform and compact, the dissolution of manganese is effectively reduced, and the cycle performance of the lithium ion secondary battery is improved. . Therefore, the lithium ion secondary battery electrolyte comprises the compound shown in the formula I, the boric acid silicone grease compound shown in the formula II and the cyclosiloxane film-forming additive shown in the formula III, so that hydrogen fluoride produced in the battery operation process can be effectively removed, a compact film can be effectively formed on a cathode and an anode, the separation of manganese in the cathode is inhibited, the damage of the separated manganese to the anode is reduced, and the cycle performance and the storage performance of the battery are effectively improved.
Detailed Description
In order to explain technical contents, structural features, and objects and effects of the technical means in detail, the following detailed description is given with reference to specific embodiments.
As used herein, unless otherwise defined, the term "substituted" means that at least one hydrogen of the indicated group is replaced with a group selected from halogen, e.g., F, Br or Cl, hydroxy, nitro, cyano, amino (e.g., NH)2、NH(Rl00) Or N (R)l01)(R102) Wherein R isl00、Rl01And R102And may be the same or different and is independently substituted with at least one functional group selected from the group consisting of Cl to Cl0 alkyl, amide, hydrazine, hydrazone, carboxyl, substituted and unsubstituted alkyl, substituted and unsubstituted alkoxy, substituted and unsubstituted cycloaliphatic organic groups, substituted and unsubstituted aryl, substituted and unsubstituted alkenyl, substituted and unsubstituted alkynyl, substituted and unsubstituted heteroaryl, and substituted and unsubstituted heterocycloalkyl groups.
The lithium ion battery electrolyte provided by the first aspect of the invention comprises:
a lithium salt,
a non-aqueous organic solvent;
acid-removing additive, compound of formula I
Figure BDA0002101157660000041
Wherein R is1-R6Each independently selected from a halogen atom, a substituted or unsubstituted C1～20Alkyl, substituted or unsubstituted C2～20Alkenyl of, substituted or unsubstituted C6～26Aryl, substituted or unsubstituted C1～20Alkoxy, substituted or unsubstituted C6～26One of the aryloxy groups of (a); wherein the halogen atom is a fluorine atom, a chlorine atom or a bromine atom;
a compound of the formula II,
Figure BDA0002101157660000042
wherein R is21、R22、R23Each independently selected from a hydrogen atom, a substituted or unsubstituted C1～20Alkyl, substituted or unsubstituted C2～20Alkenyl, substituted or unsubstituted C2～20Alkynyl, substituted or unsubstituted C6～26One of aryl and substituted or unsubstituted phenyl;
a compound of the formula (III),
Figure BDA0002101157660000043
Figure BDA0002101157660000051
wherein R is11、R12、R13、R14、R15、R16Each independently selected from substituted or unsubstituted C1～10An alkyl group of (A), a substituted or unsubstituted carbon atom number of C6～26One of aryl groups of (1).
Wherein: the compound shown in the formula I is used as an acid removal additive, can effectively react with water and hydrogen fluoride generated in the operation process of a lithium ion secondary battery to generate a silicon fluoride product to cover the surface of a cathode and an anode and protect the cathode and the anode; the borate compound shown in the formula II is used as a cathode coordination additive, and can be coordinated with a cathode by utilizing the electron-deficient structure of the borate compound, so that the effects of protecting the cathode and inhibiting the dissolution of manganese are achieved; the film forming additive shown in the formula III can reduce manganese dissolution, and the anode film forming can reduce the damage of manganese to the cathode.
Further, the deacidification additive shown in the formula I meets the requirement of R1-R6Each independently selected from substituted or unsubstituted C1～10Alkyl, substituted or unsubstituted C2～10Alkenyl, substituted or unsubstituted C6～26One of aryl groups of (1).
The cathode coordination additive shown in the formula II satisfies R21、R22、R23Each independently selected from hydrogen atom, substituted or unsubstituted C1～10Alkyl, substituted or unsubstituted C2～10Alkenyl, substituted or unsubstituted C2～10Alkynyl, substituted or unsubstituted phenyl.
Further, the deacidification additive shown in the formula I meets the condition that R is1-R6Wherein the substituent for substituting the alkyl group, the alkenyl group, the aryl group, the alkoxy group or the aryloxy group is selected from a halogen atom, a sulfonic acid group or a sulfonyl group; wherein the halogen atom is a fluorine atom, a chlorine atom or a bromine atom;
the cathode coordination additive shown in the formula II satisfies the following conditions: at R21、R22、R23Wherein the substituent for substituting the alkyl group, the alkenyl group, the aryl group, the alkynyl group, and the phenyl group is a halogen atom, and the halogen atom is a fluorine atom, a chlorine atom, or a bromine atom;
the film-forming additive shown in the formula III satisfies the following conditions: at R11、R12、R13、R14、R15、R16Wherein the substituent for substituting the alkoxy group, the aryl group or the substituent is a halogen atom; wherein the halogen atom is fluorine atom, chlorine atom or bromine atom;
the types and the number of the substituent groups have great influence on the performance of the additive, particularly, the halogenated additive has great difference between the electron cloud distribution of the whole halogenated additive and the electron cloud distribution of the non-halogenated additive due to the strong electronegativity of halogen atoms, so that the complexing capacity of the additive and a positive electrode film is obviously enhanced, the acting force of film formation between the additive and a positive electrode is greatly enhanced, and the film formation effect of the film formation additive is effectively improved.
Further, the compound shown in the formula I is selected from one or more of the following compounds:
Figure BDA0002101157660000061
Figure BDA0002101157660000071
the compound shown in the formula II is selected from one or more of methyl borate, ethyl borate and propyl borate;
the compound shown in the formula III is selected from one or more of hexamethylcyclotrisiloxane, pentamethyl-phenyl cyclotrisiloxane and hexafluoromethyl cyclotrisiloxane.
Further, the mass percentage of the compound shown in the formula I in the electrolyte is 0.05-3%, and preferably, the mass percentage of the compound shown in the formula I in the electrolyte is 0.1-2%;
the mass percentage of the compound shown in the formula II in the electrolyte is 0.05-3%, preferably, the mass percentage of the compound shown in the formula II in the electrolyte is 0.1-2%;
the mass percentage of the compound shown in the formula III in the electrolyte is 0.05-5%, and preferably, the mass percentage of the compound shown in the formula II in the electrolyte is 1-3%.
Further, the non-aqueous organic solvent is selected from one or more of ethylene carbonate, propylene carbonate, butylene carbonate, fluoroethylene carbonate, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, 1, 4-butyrolactone, methyl propionate, methyl butyrate, ethyl acetate, ethyl propionate, and ethyl butyrate.
In a second aspect of the present invention, the present invention provides a lithium ion secondary battery comprising:
a positive electrode containing a positive electrode active material containing a manganese element;
an anode comprising an anode active material and
the electrolyte according to the first aspect of the invention.
Further, the positive active material comprises one or more of lithium manganate, lithium nickel manganese oxide and lithium nickel cobalt manganese oxide.
Further, the positive electrode active material contains lithium manganate, and the mass content of the lithium manganate in the positive electrode active material is 10% -100%.
Further, the positive electrode active material further contains lithium nickel manganese oxide.
The manganese element contained in the positive active material can improve the stability and safety of the material, however, in the lithium ion deintercalation process, part of the manganese element can be dissolved out, the dissolved manganese element can be electrically migrated to the negative electrode, and an SEI (solid electrolyte interphase) film of the negative electrode is damaged, so that the cycle performance of the lithium ion secondary battery is reduced, and the manganese element dissolution phenomenon can be effectively improved when the electrolyte disclosed by the first aspect of the invention is used for the lithium ion secondary battery containing the manganese element positive material, mainly because the acid removal additive, the cathode coordination additive and the film forming additive in the electrolyte disclosed by the first aspect of the invention are
In the following examples, comparative examples and test examples, the reagents, materials and instruments used were all conventional reagents, conventional materials and conventional instruments, which are commercially available unless otherwise specified, and the reagents involved therein were also synthesized by a conventional synthesis method.
In the following examples, comparative examples and test examples, the reagents used were as follows:
the acid-removing additive is a compound shown in a formula I:
Figure BDA0002101157660000091
the compound can effectively react with water and hydrogen fluoride generated in the operation process of the lithium ion secondary battery to generate silicon fluoride products to cover the surface of the cathode and the anode so as to protect the cathode and the anode.
The embodiment adopts the following steps: bis (trimethylsilyl) sulfate ester, bis (trimethylsilyl) sulfate,
Figure BDA0002101157660000092
the cathode coordination additive is a compound containing borate, and can coordinate with the cathode by utilizing the electron-deficient structure of the borate compound to achieve the effects of protecting the cathode and inhibiting the dissolution of manganese. In other embodiments, other coordination additives that satisfy the electron deficient structure may be substituted.
In the present embodiment, 3 kinds of borate-containing compounds are selected, including:
a1: methyl borate, formula:
Figure BDA0002101157660000093
a2: ethyl borate, formula:
Figure BDA0002101157660000101
a3: propyl borate, formula:
Figure BDA0002101157660000102
the film forming additive is a cyclosiloxane compound, the cathode film forming can reduce manganese dissolution, and the anode film forming can reduce the damage of manganese to the cathode. This embodiment selects 3 cyclosiloxane compounds, including:
b1: hexamethylcyclotrisiloxane of formula:
Figure BDA0002101157660000103
b2: pentamethyl-phenyl cyclotrisiloxane of formula:
Figure BDA0002101157660000104
b3: hexafluoromethylcyclotrisiloxane, of formula:
Figure BDA0002101157660000105
lithium salt: the embodiment adopts the following steps: lithium hexafluorophosphate LiPF6；
The organic solvent is selected from the following components: ethylene Carbonate (EC), Ethyl Methyl Carbonate (EMC);
a positive electrode active material. In this embodiment, lithium manganate is selected as the positive electrode active material containing manganese.
And (3) isolation film: a PE porous polymer film is used as a separation film.
Examples 1-13 preparation of lithium ion batteries (hereinafter, referred to simply as batteries) 1-13
Batteries 1-13 were all prepared as follows:
1 negative plate preparation
Graphite serving as a negative electrode active material, acetylene black serving as a conductive agent, styrene butadiene rubber serving as a binder and sodium carboxymethyl cellulose serving as a thickening agent are mixed according to the weight ratio of graphite: acetylene black: styrene-butadiene rubber: mixing sodium carboxymethylcellulose (95: 2:2: 1), adding deionized water, and fully stirring and mixing to form uniform negative electrode slurry; and coating the slurry on a copper foil of a negative current collector, and then drying and cold pressing to obtain the negative plate.
2 preparation of Positive plate
Mixing a positive active material, namely spinel lithium manganate, a conductive agent, namely acetylene black, and a binder, namely polyvinylidene fluoride according to a weight ratio, adding a solvent, namely N-methyl pyrrolidone, and fully stirring and mixing to form uniform positive slurry; and coating the slurry on an aluminum foil of a positive current collector, and then drying and cold pressing to obtain the positive plate.
3 preparation of electrolyte
The electrolyte was prepared as follows:
at water content<In a 10ppm argon atmosphere glove box, EC and EMC are calculated according to the weight ratio of EC: EMC 3: 7 mixing to obtain a mixed solvent, and fillingSeparately dried lithium salt LiPF6Dissolving in the mixed solvent, adding the silicate compound containing sulfuric acid, the borate compound containing boric acid and the cyclic siloxane additive with the contents and types shown in the table 1, and uniformly stirring to obtain the electrolyte, wherein the LiPF is6The concentration of (2) is 1 mol/L.
Preparation of 4 cell
The batteries 1 to 13 are all prepared according to the following method:
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; and placing the bare cell in an outer packaging foil, injecting the prepared electrolyte into the dried battery, and then carrying out vacuum packaging, standing, formation, shaping and other processes to obtain the battery.
In the above-described battery production process, the contents of the compound represented by formula i, the borate-containing compound, and the cyclic siloxane-based additive used in each electrolyte are as shown in table 1 below.
In table 1, the contents of the additives are all weight percentages calculated based on the total weight of the electrolyte.
Table 1 examples 1-13 electrolyte additive compositions
Figure BDA0002101157660000121
Comparative examples 1 to 13 lithium ion batteries (hereinafter, both will be referred to simply as batteries) 1#-13#Preparation of
Comparative examples 1 to 13
Battery 1#-13#The preparation method comprises the following steps:
the method of manufacturing the battery in example 1 was repeated except that the content of the additive in the electrolyte was changed during the process of preparing the electrolyte, the content of the additive in the electrolyte was added according to the kind and content in table 2, and the remaining conditions were maintained.
The additive contents selected in each cell during the above-described battery preparation process are shown in table 2.
Table 2 comparative example 1#-13#Electrolyte additive composition of
Figure BDA0002101157660000131
Note: in table 2, "/" indicates that no substance of any kind is added.
Electrochemical test method
(1) 45 ℃ cycle performance test of battery
The following tests were carried out on the batteries prepared in the examples and comparative examples:
at 45 ℃, the lithium ion secondary battery is charged to 4.3V by constant current of 1C, further charged to current of 0.05C by constant voltage of 4.3V, and then discharged to 3V by constant current of 1C, which is a charge-discharge cycle process, and the discharge capacity of the time is the discharge capacity of the 1 st cycle. And (3) carrying out a plurality of cycles of charge and discharge tests on the battery according to the mode, detecting to obtain the discharge capacity of the 100 th cycle, and calculating the capacity retention rate of the battery after the cycle according to the following formula. In addition, the test results are shown in table 3 below.
Capacity retention (%) after 100 cycles of the battery was [ discharge capacity at 100 cycles/discharge capacity at 1 cycle ] × 100%
(2) 60 ℃ storage Performance test of Battery
The following tests were carried out on the batteries prepared in the examples and comparative examples:
charging the battery to 4.3V at a constant current of 1C at 25 ℃, then charging the battery to a current of less than 0.05C at a constant voltage of 4.3V, and discharging the battery to 3.0V at a constant current of 1C; charging the battery to 4.3V by using a constant current of 1C, then charging the battery by using a constant voltage of 4.3V until the current is less than 0.05C, then storing the battery at 60 ℃ for 30 days, and after the storage is finished, discharging the battery to 3.0V by using a constant current of 1C; charging to 4.3V with 1C constant current, charging the battery with 4.3V constant voltage until the current is less than 0.05C, discharging to 3.0V with 1C constant current, repeating the steps for 3 times, and taking the last discharge capacity as the recoverable capacity. In addition, the test results are shown in table 3 below.
The storage recoverable capacity ratio (%) of the battery is [ recoverable capacity after high-temperature storage of the battery/capacity before storage of the battery ] × 100%.
TABLE 3 electrochemical Properties of examples 1-13 and comparative examples 1-13
Figure BDA0002101157660000141
Figure BDA0002101157660000151
From the relevant data in table 3 above, the following analyses were performed:
analysis of cycling, storing test results
As can be seen from the capacity retention rates after cycling obtained in examples 1 to 13 and the capacity retention rate after cycling obtained in comparative example 1, the electrolyte contains the compound shown in the formula I, the compound containing borate and the cyclosiloxane film-forming additive, and the battery has higher cycle capacity retention rate and storage capacity retention rate.
From the capacity retention rates after the cycling and the storage obtained in the comparative examples 1 to 13 of the battery, it can be known that the comparative example 1 does not add any additive, so that the organic solvent can generate more side reactions on the surface of the pole piece, and the electrolyte is easier to decompose to generate more hydrogen fluoride, so that the capacity retention rate of the battery is low.
In comparative examples 2 to 7 and comparative examples 8, 10 and 12, the compound of formula I, the borate-containing compound and the cyclosiloxane-based film-forming additive were added, respectively, but the performance was not improved much because a single additive could not form a film effectively or scavenge hydrogen fluoride.
In comparative examples 9, 11 and 13, the content of the film-forming additive containing the compound represented by formula i, the borate-containing compound and the cyclic siloxane was too large, and the excessive additive caused the decrease of the electrolyte conductivity and other properties and the increase of the interface resistance, thereby deteriorating the cycle and storage properties of the battery at high temperature.
The mass percentage of the compound containing the formula I in the electrolyte is 0.05-3%; the mass percentage of the borate-containing compound in the electrolyte is 0.05-3%; when the mass percentage of the cyclosiloxane film-forming additive in the electrolyte is 0.05-5%, the cycle and storage performance of the battery at high temperature is improved. The mass percentage of the compound containing the formula I in the electrolyte is 0.1-2%; the mass percentage of the borate-containing compound in the electrolyte is 0.1-2%; when the mass percentage of the cyclosiloxane film-forming additive in the electrolyte is 1-3%, the cycle and storage performance of the battery at high temperature is further improved.
From the above results, it can be seen that when the positive electrode contains manganese as an active material and the electrolyte contains the compound represented by formula i, the borate-containing compound and the cyclic siloxane-based film-forming additive, the capacity retention rate of the battery after cycling and storage is effectively improved.
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.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or terminal that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or terminal. Without further limitation, an element defined by the phrases "comprising … …" or "comprising … …" does not exclude the presence of additional elements in a process, method, article, or terminal that comprises the element. Further, herein, "greater than," "less than," "more than," and the like are understood to exclude the present numbers; the terms "above", "below", "within" and the like are to be understood as including the number.
It should be noted that, although the above embodiments have been described herein, the invention is not limited thereto. Therefore, based on the innovative concepts of the present invention, the technical solutions of the present invention can be directly or indirectly applied to other related technical fields by making changes and modifications to the embodiments described herein or by using equivalent structures or equivalent processes performed in the present specification, and are included in the scope of the present invention.

Claims (15)

1. A lithium ion battery electrolyte containing manganese element in a positive electrode comprises:
a lithium salt;
a non-aqueous organic solvent;
a compound of the formula I,
Figure 192623DEST_PATH_IMAGE001
formula I
Wherein R is1-R6Each independently selected from a halogen atom, a substituted or unsubstituted C1～20Alkyl, substituted or unsubstituted C2～20Alkenyl of, substituted or unsubstituted C6～26Aryl, substituted or unsubstituted C1～20Alkoxy, substituted or unsubstituted C6～26One of the aryloxy groups of (a); wherein the halogen atom is a fluorine atom, a chlorine atom or a bromine atom;
a compound of the formula II,
Figure 640922DEST_PATH_IMAGE002
formula II
Wherein R is21、R22、R23Each independently selected from a hydrogen atom, a substituted or unsubstituted C1～20Alkyl, substituted or unsubstituted C2～20Alkenyl, substituted or unsubstituted C2～20Alkynyl, substituted or unsubstituted C6～26One of aryl groups;
a compound of the formula (III),
Figure 92763DEST_PATH_IMAGE003
formula III
Wherein R is11、R12、R13、R14、R15、R16Each independently selected from substituted or unsubstituted C1～10An alkyl group of (A), a substituted or unsubstituted carbon atom number of C6～26One of aryl groups of (1).
2. The electrolyte of claim 1, wherein the electrolyte is characterized by
R21、R22、R23Each independently selected from a hydrogen atom, a substituted or unsubstituted phenyl group.
3. The electrolyte of claim 1,
R1-R6each independently selected from substituted or unsubstituted C1～10Alkyl, substituted or unsubstituted C2～10Alkenyl, substituted or unsubstituted C6～26One of the aryl groups of (a);
R21、R22、R23each independently selected from hydrogen atom, substituted or unsubstituted C1～10Alkyl, substituted or unsubstituted C2～10Alkenyl, substituted or unsubstituted C2～10Alkynyl, substituted or unsubstituted phenyl.
4. The electrolyte of claim 1, wherein the electrolyte is characterized by
At R1-R6Wherein the substituent for substituting the alkyl group, the alkenyl group, the aryl group, the alkoxy group or the aryloxy group is selected from a halogen atom, a sulfonic acid group or a sulfonyl group; wherein the halogen atom is a fluorine atom, a chlorine atom or a bromine atom;
at R21、R22、R23Wherein the substituent for substituting the alkyl group, the alkenyl group, the aryl group, and the alkynyl group is a halogen atom, and the halogen atom is a fluorine atom, a chlorine atom, or a bromine atom;
at R11、R12、R13、R14、R15、R16Wherein a substituent for substituting the alkoxy group or the aryl group is a halogen atom; wherein the halogen atom is fluorine atom, chlorine atom or bromine atom.
5. The electrolyte of claim 2, wherein the electrolyte is characterized by
At R1-R6Wherein the substituent for substituting the alkyl group, the alkenyl group, the aryl group, the alkoxy group or the aryloxy group is selected from a halogen atom, a sulfonic acid group or a sulfonyl group; wherein the halogen atom is a fluorine atom, a chlorine atom or a bromine atom;
at R21、R22、R23Wherein the substituent for substituting the phenyl group is a halogen atom, and the halogen atom is a fluorine atom, a chlorine atom, or a bromine atom;
at R11、R12、R13、R14、R15、R16Wherein a substituent for substituting the alkoxy group or the aryl group is a halogen atom; wherein the halogen atom is fluorine atom, chlorine atom or bromine atom.
6. The electrolyte of claim 4 or 5,
the compound shown in the formula I is selected from one or more of the following compounds:
Figure DEST_PATH_IMAGE004
,
Figure 940502DEST_PATH_IMAGE005
,
Figure DEST_PATH_IMAGE006
,
Figure 692558DEST_PATH_IMAGE007
,
Figure DEST_PATH_IMAGE008
,
Figure 341452DEST_PATH_IMAGE009
,
Figure DEST_PATH_IMAGE010
,
Figure 326594DEST_PATH_IMAGE011
,
Figure DEST_PATH_IMAGE012
,
Figure 151593DEST_PATH_IMAGE013
；
the compound shown in the formula II is selected from one or more of methyl borate, ethyl borate and propyl borate;
the compound shown in the formula III is selected from one or more of hexamethylcyclotrisiloxane, pentamethyl-phenyl cyclotrisiloxane and hexafluoromethyl cyclotrisiloxane.
7. The electrolyte as claimed in claim 1, wherein the compound represented by formula i is 0.05% to 3% by mass in the electrolyte;
the mass percentage of the compound shown in the formula II in the electrolyte is 0.05-3%;
the mass percentage of the compound shown in the formula III in the electrolyte is 0.05-5%.
8. The electrolyte as claimed in claim 7, wherein the compound of formula I is present in the electrolyte in an amount of 0.1-2% by weight.
9. The electrolyte as claimed in claim 7, wherein the compound represented by formula II is contained in the electrolyte in an amount of 0.1-2% by mass.
10. The electrolyte of claim 7, wherein the compound of formula III is present in the electrolyte in an amount of 1-3% by weight.
11. The electrolyte of claim 1, wherein the non-aqueous organic solvent is selected from one or more of ethylene carbonate, propylene carbonate, butylene carbonate, fluoroethylene carbonate, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, propyl methyl carbonate, propyl ethyl carbonate, 1, 4-butyrolactone, methyl propionate, methyl butyrate, ethyl acetate, ethyl propionate, and ethyl butyrate.
12. A lithium ion secondary battery comprising:
a positive electrode containing a positive electrode active material containing a manganese element;
an anode comprising an anode active material and
the electrolyte of any one of claims 1-11.
13. The lithium ion secondary battery of claim 12, wherein the positive active material comprises one or more of lithium manganate, lithium nickel manganate, and lithium nickel cobalt manganate.
14. The lithium ion secondary battery according to claim 13, wherein the positive electrode active material contains lithium manganate, and a content of the lithium manganate in the positive electrode active material is 10% to 100% by mass.
15. The lithium ion secondary battery according to claim 14, wherein the positive electrode active material further comprises lithium nickel manganese oxide.
CN201910535886.2A 2019-06-20 2019-06-20 Lithium ion battery electrolyte and lithium ion secondary battery Active CN112117490B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910535886.2A CN112117490B (en) 2019-06-20 2019-06-20 Lithium ion battery electrolyte and lithium ion secondary battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910535886.2A CN112117490B (en) 2019-06-20 2019-06-20 Lithium ion battery electrolyte and lithium ion secondary battery

Publications (2)

Publication Number Publication Date
CN112117490A CN112117490A (en) 2020-12-22
CN112117490B true CN112117490B (en) 2021-07-23

Family

ID=73795988

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910535886.2A Active CN112117490B (en) 2019-06-20 2019-06-20 Lithium ion battery electrolyte and lithium ion secondary battery

Country Status (1)

Country Link
CN (1) CN112117490B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112768770A (en) * 2021-01-19 2021-05-07 惠州锂威新能源科技有限公司 Electrolyte and lithium ion battery containing same

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010044883A (en) * 2008-08-08 2010-02-25 Mitsui Chemicals Inc Nonaqueous electrolyte and lithium secondary battery
JP2011054406A (en) * 2009-09-01 2011-03-17 Mitsui Chemicals Inc Nonaqueous electrolyte and nonaqueous electrolyte secondary battery using the same
WO2018164124A1 (en) * 2017-03-07 2018-09-13 住友精化株式会社 Additive for nonaqueous electrolyte solutions, nonaqueous electrolyte solution, and electricity storage device

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010044883A (en) * 2008-08-08 2010-02-25 Mitsui Chemicals Inc Nonaqueous electrolyte and lithium secondary battery
JP2011054406A (en) * 2009-09-01 2011-03-17 Mitsui Chemicals Inc Nonaqueous electrolyte and nonaqueous electrolyte secondary battery using the same
WO2018164124A1 (en) * 2017-03-07 2018-09-13 住友精化株式会社 Additive for nonaqueous electrolyte solutions, nonaqueous electrolyte solution, and electricity storage device

Also Published As

Publication number Publication date
CN112117490A (en) 2020-12-22

Similar Documents

Publication Publication Date Title
CN108123172B (en) Electrolyte and secondary lithium battery
CN109860709B (en) Electrolyte for improving low-temperature performance of lithium ion battery and lithium ion battery containing electrolyte
CN110970621B (en) Lithium ion battery
CN108242557B (en) Electrolyte solution and secondary battery
CN105914402B (en) A kind of nonaqueous electrolytic solution and lithium ion battery
CN108258297B (en) Electrolyte and lithium ion battery
CN109428119B (en) Lithium ion battery and non-aqueous electrolyte thereof
CN110808411B (en) Electrolyte and lithium ion battery
CN110808412B (en) Electrolyte and lithium ion battery
CN109004275B (en) Electrolyte solution and secondary battery
CN105895957A (en) Battery fluid and lithium ion battery
CN108630989A (en) Electrolyte and lithium ion battery
CN109390629B (en) Electrolyte and battery
CN109004274B (en) Electrolyte solution and secondary battery
CN110783628A (en) Non-aqueous electrolyte of lithium ion battery and lithium ion battery using same
CN114512721A (en) Lithium ion battery non-aqueous electrolyte and lithium ion battery
CN108206299B (en) Lithium ion battery and electrolyte thereof
CN116525951A (en) Electrolyte, electrolyte and application of electrolyte
CN110957528B (en) Additive for battery electrolyte, lithium ion battery electrolyte and lithium ion battery
CN113130990A (en) Electrolyte and secondary battery using same
CN109309248B (en) Electrolyte solution and secondary battery
CN112117490B (en) Lithium ion battery electrolyte and lithium ion secondary battery
CN107240716B (en) Electrolyte, positive electrode and preparation method thereof, and lithium ion battery
CN110676513A (en) Lithium battery electrolyte and lithium battery
CN116646598A (en) Electrolyte and 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