Shenzhen Capchem Technology Co., Ltd.

Shiguang Hu

Hao Zhang

Li Wei Wang

Hui Li

Qiao Shi

Muchong Lin

Jiaojiao Yun

Xionggui Lin

Zhaohui Deng

Qun Chen

Ling Zhong

Zhongtian Zheng

Xue Zhou

Qi Huang

Chang'an Zeng

Changchun Chen

Dejun Xiong

Guanjie Ai

Qi Guo

Xiaoxia Xiang

Yonghong Deng

Yunxian Qian

Ruixing Liu

Chaowei Cao

Kai Tu

Chunhua Liu

Hongmei Li

Zhou He

Hailing Zhang

Chi Wang

To solve the problem that the existing non-aqueous electrolyte for a lithium ion battery cannot ensure the high-temperature storage performance and cycle performance at the same time, the invention provides a non-aqueous electrolyte for a lithium ion battery, comprising a solvent, a lithium salt and a compound represented by structural formula 1 and/or structural formula 2: Meanwhile, the invention also discloses a lithium ion battery comprising the non-aqueous electrolyte for a lithium ion battery. The non-aqueous electrolyte provided by the invention can effectively improve the cycle performance and high-temperature storage performance of lithium ion batteries.

Non-aqueous electrolyte for a lithium ion battery and lithium ion battery

Provided is a non-aqueous electrolyte, comprising a solvent, a lithium salt, an additive A and an additive B, the additive A is selected from compound represented by structural formula 1, and the additive B is selected from one or more of compounds represented by structural formula 2 and structural formula 3:

Non-aqueous electrolyte and lithium ion battery

In order to solve the problems of insufficient high-temperature storage performance and high-temperature cycle performance of the existing lithium ion battery, the present application provides a non-aqueous electrolyte for lithium ion battery, comprising a bicyclic sulfate compound and a compound A represented by structural formula 1. In structural formula 1, R, R, R, R, Rand Rare each independently selected from hydrogen, fluorine atom or a group containing 1˜5 carbon atoms. Meanwhile, the application also discloses a lithium ion battery comprising the non-aqueous electrolyte for lithium ion battery. The non-aqueous electrolyte for lithium ion battery provided by the application is beneficial to improving high-temperature storage and high-temperature cycle performance of battery.

Non-aqueous electrolyte for lithium ion battery and lithium ion battery

The application provides a non-aqueous electrolyte for lithium ion battery. The non-aqueous electrolyte for lithium ion battery comprises a compound A represented by formula I and a compound B represented by formula II, In formula I, R, Rand Rare independently selected from C1-C5 alkyl or haloalkyl, C2-C5 unsaturated hydrocarbon group or unsaturated halohydrocarbon group, and at least one of R, Rand Ris the unsaturated hydrocarbon group or unsaturated halohydrocarbon group; In formula II, R, R, R, R, Rand Rare each independently selected from one of hydrogen atom, fluorine atom and C1-C5 group. The non-aqueous electrolyte for lithium ion battery provided by the application enables the battery to have excellent cycle performance and high-temperature storage performance through the synergistic effect of the compound A and the compound B.

A non-aqueous electrolyte for a lithium-ion battery and a lithium-ion battery. The non-aqueous electrolyte includes an unsaturated phosphate compound and a cyclic unsaturated carboxylic anhydride compound. The unsaturated phosphate compound has a structure represented by structural formula (4). R, Rand Rare each independently selected from a hydrocarbon group having 1 to 5 carbon atoms, and at least one of R, Rand Ris an unsaturated hydrocarbon group having a double bond or a triple bond. The unsaturated cyclic carboxylic anhydride compound having a structure represented by Structural Formula 5. Ris selected from the group consisting of an alkenylene group having 2 to 4 carbon atoms or a fluorinated alkenylene group having 2 to 4 carbon atoms. By means of the synergistic effect of two compounds, the non-aqueous electrolyte has excellent high-temperature cycling performance and storage performance, and also has lower impedance and good low-temperature performance.

Non-aqueous electrolyte for lithium-ion battery and lithium-ion battery

Provided is a secondary battery, comprising a positive electrode, the positive electrode comprises a positive electrode material layer, and the positive electrode material layer comprises a positive electrode active material and a compound represented by structural formula I: 

Secondary battery

In order to solve the problem of insufficient cycle performance and high-temperature storage performance of the existing non-aqueous electrolyte for lithium ion battery containing maleic anhydride copolymer, the application provides a non-aqueous electrolyte for lithium ion battery. The non-aqueous electrolyte for lithium ion battery comprises a compound A represented by formula I and a compound B represented by formula II,  In formula I, Rand Rare independently selected from one of hydrogen atom, halogen atom, &#x2014;O&#x2014;Ror aryl, wherein n is a positive integer and Ris a C1-C4 alkyl group; In formula II, R, R, R, R, Rand Rare each independently selected from one of hydrogen atom, fluorine atom and C1-C5 group. The non-aqueous electrolyte for lithium ion battery provided by the invention can improve the cycle stability and high-temperature storage performance of the battery through the effections of compound A and compound B.

In order to overcome the problems of influence of residual moisture, poor cycle performance and poor high-temperature storage performance in the existing lithium ion battery, the application provides a non-aqueous electrolyte for lithium ion battery, comprising a solvent, lithium salt and maleic anhydride copolymer, wherein the weight-average molecular weight of the maleic anhydride copolymer is less than or equal to 500,000; Furthermore, the percentage mass content of the maleic anhydride copolymer is 0.5% or more based on the total mass of the non-aqueous electrolyte being 100%. Meanwhile, the application also provides a lithium ion battery comprising the non-aqueous electrolyte. The non-aqueous electrolyte provided by the application is added with maleic anhydride copolymer with a content of more than 0.5% and a weight-average molecular weight of less than 500,000, so that the high-temperature storage and cycle performances of the lithium ion battery are effectively improved.

To solve the problems that the existing non-aqueous electrolyte for lithium ion battery containing fluorinated solvent generates serious gas expansion when improving high-temperature cycle performance and affects high-temperature safety performance of battery. The application provides a non-aqueous electrolyte for lithium ion battery. The non-aqueous electrolyte for lithium ion battery comprises a compound A and a compound B, wherein the compound A is at least one of compounds represented by the following structural formula I, formula II and formula III; the compound B is a compound represented by the following structural formula IV; formula I: R&#x2014;COO&#x2014;R; formula II: R&#x2014;OCOO&#x2014;R. The non-aqueous electrolyte for lithium ion battery provided by the invention contains both the compound A and the compound B, the synergistic effect of compound A and compound B can effectively improve high-temperature cycle performance and high-temperature storage performance of battery, and can also give consideration to low-temperature performance of battery. 

Provided is a non-aqueous electrolyte for lithium ion battery, comprising a compound A represented by structural formula I and a compound B represented by structural formula II: Wherein, in formula I, Ris selected from alkylene having 1-5 carbon atoms or fluorine substituted alkylene having 1-5 carbon atoms; Ris selected from anyone of alkylene having 1-5 carbon atoms, fluorine substituted alkylene having 1-5 carbon atoms or carbonyl; In formula II, R, R, R, R, Rand Rare each independently selected from hydrogen, fluorine atom or a group containing 1-5 carbon atoms. The compound A and compound B of the non-aqueous electrolyte can form a passivation film formed by reduction, decomposition and combination reactions on the surface of negative electrode material of lithium-ion battery, thereby improving thermal stability of the passivation film and high-temperature cycle and storage performance of the battery.

Provide is a non-aqueous electrolyte for lithium ion battery, comprising a compound represented by structural formula I:  In formula I, R, R, Rand Rare each independently selected from hydrogen atom, fluorine atom, cyano group, hydrocarbyl group or halogenated hydrocarbyl group having 1-5 carbon atoms, oxygen-containing hydrocarbyl group having 1-5 carbon atoms, silicon-containing hydrocarbyl group having 1-5 carbon atoms, X is a &#x2014;O&#x2014;R&#x2014;CN group, Ris a hydrocarbyl group or a halogenated hydrocarbyl group having 1-5 carbon atoms, m, n, z and y are integers of 0 or 1, and m+n+y+z&#x2260;0. When the non-aqueous electrolyte is used for lithium ion battery, the decomposition of electrolyte on the surface of electrode can be inhibited, and the high-temperature storage performance is improved with less gas generation and small expansion rate, therefore the high-temperature cycle performance and high-temperature storage performance of the battery are effectively improved.

A non-aqueous electrolyte for a lithium-ion battery and a lithium-ion battery. The non-aqueous electrolyte comprises unsaturated phosphate compounds and unsaturated cyclic carboxylic acid anhydride compounds. The unsaturated phosphate compounds have the structure illustrated in structural formula 4; structural formula 4: R, R, and Rare independently selected from hydrocarbon groups having 1-5 carbon atoms respectively, and at least one of R, R, and Ris an unsaturated hydrocarbon group containing double bonds or triple bonds; the unsaturated cyclic carboxylic acid anhydride compounds have the structure illustrated in structural formula 5; structural formula 5: Ris independently selected from vinylidene having 2-4 carbon atoms or fluoro-substituted vinylidene. By means of the synergistic effect of two compounds, the non-aqueous electrolyte has excellent high-temperature cycling performance and storage performance, and also has lower impedance and good low-temperature performance. 

A lithium-ion battery non-aqueous electrolyte and a lithium-ion battery. The non-aqueous electrolyte comprises at least one selected from the compounds represented by structural formula I and II; in formula I, R1 and R2 are independently selected from alkenyl having 2-5 carbon atoms and alkynyl having 2-5 carbon atoms; in formula II, R3 is selected from alkenyl having 2-5 carbon atoms and alkynyl having 2-5 carbon atoms. The compound represented by formula I or II is added in the electrolyte; the compound contains unsaturated bond(s) and hexafluorisopropyl; the unsaturated bond(s) form passivation film on cathode and anode surfaces to inhibit decomposition of the electrolyte on the cathode & anode surface and damage of the cathode material structure; moreover, the polymerization degree of unsaturated bond(s) can be inhibited to some extent due to steric hindrance relationship of fluoroisopropyl functional groups, so as to improve high-temperature performance of the lithium-ion battery while guaranteeing low-temperature performance.

Non-aqueous electrolyte of lithium-ion battery and lithium-ion battery

To address the existing problem of insufficient cycle performance and high-temperature storage performance of lithium ion battery electrolyte at high pressure, the disclosure provides a non-aqueous electrolyte for lithium ion battery. The non-aqueous electrolyte for lithium ion battery comprises a cyano-containing compound A and a compound B represented by formula I,  The non-aqueous electrolyte for lithium ion battery provided by the disclosure contains both the cyano-containing compound A and the compound B, so that the lithium ion battery containing the non-aqueous electrolyte can have better cycle performance and high-temperature storage performance at high pressure.

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Guangdong, China

Shiguang Hu