WO2015032215A1

WO2015032215A1 - Nonaqueous organic high-voltage electrolyte additive, nonaqueous organic high-voltage electrolyte and lithium ion secondary battery

Info

Publication number: WO2015032215A1
Application number: PCT/CN2014/078010
Authority: WO
Inventors: 许梦清; 邢丽丹; 李伟善; 杨同勇; 安伟峰
Original assignee: 华为技术有限公司
Priority date: 2013-09-05
Filing date: 2014-05-21
Publication date: 2015-03-12
Also published as: CN104425841B; CN104425841A

Abstract

A nonaqueous organic high-voltage electrolyte additive that the chemical structure as represented by formula (I), wherein R_a, R_b, R_c and R_d are oxygen or organic group, and the organic group comprises one selected from alkyl, alkylene, alkyne, aryl, halogenated alkyl, halogenated alkylene, halogenated alkyne, and halogenated aryl; wherein i, j, q and t are 0 or 1; x, n, e and h are integers between 1 and 4, f is an integer between 0 and (2e+1), k is an integer between 0 and (2h+1), m is an integer between 0 and (2n+1), and y is an integer between 0 and (2x+1). The nonaqueous organic high-voltage electrolyte additive is oxidized and decomposed in the charging process of a high-voltage lithium ion secondary battery, thus the formation of a protective film on the surface of an anode material is promoted subsequently, so that the cycle performance and discharge capability of the lithium ion secondary battery under the high voltage can be improved.

Description

一种非水有机高电压电解液添加剂、非水有机高电压电解液和锂离子二次电池本申请要求于 2013年 9月 5日提交中国专利局的申请号为 201310400272.6，其发明名称为 "一种非水有机高电压电解液添加剂、非水有机高电压电解液和锂离子二次电池" 的中国专利申请的优先权，其全部内容通过引用结合在本申请中。技术领域 Non-aqueous organic high-voltage electrolyte additive, non-aqueous organic high-voltage electrolyte and lithium ion secondary battery. The application request is submitted to the Chinese Patent Office on September 5, 2013, and the application number is 201310400272.6. The priority of the Chinese patent application for non-aqueous organic high-voltage electrolyte additives, non-aqueous organic high-voltage electrolytes and lithium-ion secondary batteries is hereby incorporated by reference in its entirety. Technical field

本发明涉及锂离子二次电池领域，特别是涉及一种非水有机高电压电解液添加剂、非水有机高电压电解液和锂离子二次电池。背景技术 The present invention relates to the field of lithium ion secondary batteries, and more particularly to a nonaqueous organic high voltage electrolyte additive, a nonaqueous organic high voltage electrolyte, and a lithium ion secondary battery. Background technique

随着锂离子二次电池应用领域的扩展，包括近年来大型储能电站、基站供电等新的应用场景的引入，人们对具有高能量锂离子二次电池的需求变得更加迫切。 With the expansion of the application field of lithium ion secondary batteries, including the introduction of new application scenarios such as large-scale energy storage power stations and base station power supply in recent years, the demand for high-energy lithium-ion secondary batteries has become more pressing.

为了实现锂离子二次电池的高能量，一般通过提高锂离子二次电池的工作电压或研发高能量正极材料来实现。已经报道的高电压正极材料有 LiCoP0₄、 LiNiP0₄、和 LiNio.sMnLsC 等，其充电电压平台接近或高于 5V，但与之匹配的非水有机电解液严重滞后于高电压正极材料的发展，限制了锂离子二次电池的应用。例如 lM LiPF₆溶解在碳酸酯类溶剂中形成的非水有机电解液，该非水有机电解液在高电压（4.5V 以上电压）电池体系中，充电过程中会与正极材料发生副反应进而被氧化分解，产生 C0₂、 H₂0等氧化产物， C0₂的产生对于电池的安全性能造成潜在的威胁； ¾0的产生使得 LiPF₆/碳酸酯电解质体系发生自催化反应，其中间产物 HF的产生会导致 LiMn Nio.sC^材料金属原子 Mn、 Ni的溶出，造成材料的结构发生畸变或者坍塌。最终导致锂离子二次电池循环性能下降、体积膨胀以及放电容量下降，因此无法应用于高电压锂离子二次电池体系。发明内容 In order to realize high energy of a lithium ion secondary battery, it is generally achieved by increasing the operating voltage of a lithium ion secondary battery or developing a high energy positive electrode material. High-voltage positive electrode materials have been reported, such as LiCoP0 ₄ , LiNiP0 ₄ , and LiNio.sMnLsC. The charging voltage platform is close to or higher than 5V, but the matching non-aqueous organic electrolyte seriously lags behind the development of high-voltage positive electrode materials. The application of lithium ion secondary batteries is limited. For example, lM LiPF _{6 is} dissolved in a carbonate-based solvent to form a non-aqueous organic electrolyte. In a high-voltage (4.5V or higher voltage) battery system, a side reaction occurs with the positive electrode material during charging. oxidative decomposition to produce C0 _{_2,} H ₂ 0 and other oxidation products of the C0 ₂ generated a potential threat to the safety performance of the battery; ¾0 generated such that LiPF ₆ / carbonate system electrolyte occurs autocatalytic In the reaction, the production of the intermediate product HF causes the dissolution of the metal atoms Mn and Ni of the LiMn Nio.sC^ material, causing the structure of the material to be distorted or collapsed. As a result, the cycle performance of the lithium ion secondary battery is degraded, the volume is expanded, and the discharge capacity is lowered, so that it cannot be applied to a high-voltage lithium ion secondary battery system. Summary of the invention

为解决上述问题，本发明实施例第一方面旨在提供一种非水有机高电压电解液添加剂，该非水有机高电压电解液添加剂在高电压锂离子二次电池的充电过程中被氧化分解，促进正极材料表面保护膜的形成，抑制正极材料对非水有机电解液溶剂的氧化作用。本发明实施例第二方面旨在提供一种包含上述非水有机电解液添加剂的非水有机高电压电解液，该非水有机高电压电解液能够满足 4.5V及以上高电压锂离子二次电池用。本发明实施例第三方面旨在提供一种包含上述非水有机高电压电解液的锂离子二次电池，锂离子二次电池在高电压下具有较好的循环性能和放电容量。 In order to solve the above problems, a first aspect of an embodiment of the present invention is directed to provide a non-aqueous organic high-voltage electrolyte additive which is oxidatively decomposed during charging of a high-voltage lithium ion secondary battery. Promoting the formation of a protective film on the surface of the positive electrode material and suppressing the oxidation of the positive electrode material to the solvent of the non-aqueous organic electrolyte. A second aspect of the present invention is directed to a nonaqueous organic high voltage electrolyte comprising the above nonaqueous organic electrolyte additive, which is capable of satisfying a high voltage lithium ion secondary battery of 4.5 V or higher. use. A third aspect of the embodiment of the present invention is directed to a lithium ion secondary battery comprising the above nonaqueous organic high voltage electrolyte, which has good cycle performance and discharge capacity at a high voltage.

第一方面，本发明实施例提供了一种非水有机高电压电解液添加剂，所述非水有机高电压电解液添加剂的化学结构式如式（ I )所示： In a first aspect, an embodiment of the present invention provides a non-aqueous organic high-voltage electrolyte additive, and the chemical structural formula of the non-aqueous organic high-voltage electrolyte additive is as shown in the formula (I):

Ch h+i-kFk C„H 2n+l-mCh h+i-kFk C„H 2n+l-m

式 ( I )，其中， R_a、 R_b、 R_c和 R_d为氧或有机基团，所述有机基团包括烷基、烯烃基、炔烃基、芳香基、卤代烷基、卤代烯烃基、卤代炔烃基和卤代芳香基中的一种; 其中 i、 j、 q和 t为 0或 1 ; x、 n、 e和 h为 1 ~ 4的整数， f为 0 ~ (2e+l)的整数， k为 0 ~ (2h+l)的整数， m为 0 ~ (2n+l)的整数， y为 0 ~ (2x+l)的整数。

Formula (I), wherein R _a , R _b , R _c and R _d are an oxygen or an organic group, and the organic group includes an alkyl group, an alkene group, an alkyne group, an aryl group, a halogenated alkyl group, a halogenated alkene group One of a halogenated alkyne group and a halogenated aryl group; Where i, j, q, and t are 0 or 1; x, n, e, and h are integers from 1 to 4, f is an integer from 0 to (2e+l), and k is an integer from 0 to (2h+l) , m is an integer from 0 to (2n+l), and y is an integer from 0 to (2x+l).

优选地，所述 R_a、 R_b、 R_c和 R_d为氧、碳原子数为 1 ~ 8的烷基、碳原子数为 2 ~ 8的烯烃基、碳原子数为 2 ~ 8的炔烃基、碳原子数为 6 ~ 8的芳香基、碳原子数为 1 ~ 8的卤代烷基、碳原子数为 2 ~ 8的卤代烯烃基、碳原子数为 2 ~ 8 的卤代炔烃基或碳原子数为 6 ~ 8的卤代芳香基。 Preferably, the R _a , R _b , R _c and R _d are oxygen, an alkyl group having 1 to 8 carbon atoms, an alkene group having 2 to 8 carbon atoms, and an alkyne having 2 to 8 carbon atoms. a hydrocarbon group, an aromatic group having 6 to 8 carbon atoms, a halogenated alkyl group having 1 to 8 carbon atoms, a halogenated alkene group having 2 to 8 carbon atoms, a halogenated alkynyl group having 2 to 8 carbon atoms or A halogenated aromatic group having 6 to 8 carbon atoms.

优选地，所述 R_a、 R_b、 R_c和 R_d为碳原子数为 2 ~ 6的烷基、碳原子数为 2 ~ 6的烯烃基、碳原子数为 2 ~ 6的炔烃基、碳原子数为 2 ~ 6的卤代烷基、碳原子数为 2 ~ 6的卤代烯烃基和碳原子数为 2 ~ 6的卤代炔烃基中的一种。 Preferably, the R _a , R _b , R _c and R _d are an alkyl group having 2 to 6 carbon atoms, an olefin group having 2 to 6 carbon atoms, an alkyne group having 2 to 6 carbon atoms, One of a halogenated alkyl group having 2 to 6 carbon atoms, a halogenated alkene group having 2 to 6 carbon atoms, and a halogenated alkyne group having 2 to 6 carbon atoms.

优选地，所述非水有机高电压电解液添加剂的化学结构式为式 I a〜式 I f中的一种： Preferably, the non-aqueous organic high-voltage electrolyte additive has a chemical structural formula of one of the formulae Ia to If:

I a、

I b、

I f。

I a,

I b,

I f.

本发明实施例第一方面提供的一种非水有机高电压电解液添加剂可用在锂离子二次电池的制备中，锂离子二次电池在充电过程中，正极电位不断升高，该非水有机高电压电解液添加剂将促进正极材料表面保护膜的形成；保护膜会覆盖正极材料表面的活性位点，阻断正极材料表面上活性位点与非水有机电解液的直接接触，抑制正极材料对非水有机电解液的氧化作用，解决了现有技术中的非水有机电解液在高电压（4.5V以上电压）电池体系中易与正极材料发生副反应导致锂离子二次电池循环性能下降、体积膨胀以及放电容量下降的问题的问题，从而提高高电压下锂离子二次电池的循环性能和放电容量。 A non-aqueous organic high-voltage electrolyte additive provided by the first aspect of the present invention can be used in the preparation of a lithium ion secondary battery. During the charging process of the lithium ion secondary battery, the positive electrode potential is continuously increased, and the non-aqueous organic The high voltage electrolyte additive will promote the formation of a protective film on the surface of the positive electrode material; Covering the active site on the surface of the positive electrode material, blocking the direct contact between the active site on the surface of the positive electrode material and the non-aqueous organic electrolyte, inhibiting the oxidation of the positive electrode material on the non-aqueous organic electrolyte, and solving the non-aqueous in the prior art The organic electrolyte is easily reacted with the positive electrode material in a high voltage (above 4.5V voltage) battery system, causing problems in the cycle performance, volume expansion, and discharge capacity of the lithium ion secondary battery, thereby increasing lithium ion at high voltage. The cycle performance and discharge capacity of the secondary battery.

第二方面，本发明实施例提供了一种非水有机高电压电解液，包括：锂盐、非水有机溶剂和非水有机高电压电解液添加剂，所述非水有机高电压电解液添加剂的化学结构式如式（ I )所示: In a second aspect, an embodiment of the present invention provides a non-aqueous organic high-voltage electrolyte, comprising: a lithium salt, a non-aqueous organic solvent, and a non-aqueous organic high-voltage electrolyte additive, and the non-aqueous organic high-voltage electrolyte additive The chemical structural formula is as shown in formula (I):

( I )，其中， R_a、 R_b、 R_c和 R_d为氧或有机基团，所述有机基团包括烷基、烯烃基、炔烃基、芳香基、卤代烷基、卤代烯烃基、卤代炔烃基和卤代芳香基中的一种；其中 i、 j、 q和 t为 0或 1 ; x、 n、 e和 h为 1 ~ 4的整数， f为 0 ~ (2e+l)的整数， k为 0 ~ (2h+l)的整数， m为 0 ~ (2n+l)的整数， y为 0 ~ (2x+l)的整数。

(I), wherein R _a , R _b , R _c and R _d are an oxygen or an organic group, and the organic group includes an alkyl group, an alkene group, an alkyne group, an aryl group, a halogenated alkyl group, a halogenated alkene group, One of a haloalkynyl group and a halogenated aryl group; wherein i, j, q, and t are 0 or 1; x, n, e, and h are integers from 1 to 4, and f is 0 to (2e+l) The integer, k is an integer from 0 to (2h+l), m is an integer from 0 to (2n+l), and y is an integer from 0 to (2x+l).

优选地，所述 R_a、 R_b、 R_c和 R_d为碳原子数为 2 ~ 6的烷基、碳原子数为 2 ~ 6的烯烃基、碳原子数为 2 ~ 6的炔烃基、碳原子数为 2 ~ 6的卤代烷基、碳原子数为 2 ~ 6的卤代烯烃基和碳原子数为 2 ~ 6的卤代炔烃基中的一种。 Preferably, the R _a , R _b , R _c and R _d are an alkyl group having 2 to 6 carbon atoms, and the number of carbon atoms is 2 ~ 6 an olefin group, an alkyne group having 2 to 6 carbon atoms, a halogenated alkyl group having 2 to 6 carbon atoms, a halogenated alkene group having 2 to 6 carbon atoms, and a halogenated group having 2 to 6 carbon atoms One of the alkyne groups.

优选地，所述 I a〜式 I f中的一种： Preferably, one of said I a to formula I f:

I c、

If。

I c,

If.

其中，锂盐选自 LiPF₆、 LiBF₄、 LiC10₄、 Li ( CF₃S0₂ ) ₂N、 LiBOB (双草酸硼酸锂）、 LiDFOB (二氟草酸硼酸锂 )和 LiPF₄C₂0₄ (四氟草酸磷酸锂）中的一种或几种。 Wherein, the lithium salt is selected from the group consisting of LiPF ₆ , LiBF ₄ , LiC10 ₄ , Li ( CF ₃ S0 ₂ ) ₂ N, LiBOB (lithium bis(oxalate) borate), LiDFOB (lithium difluorooxalate borate), and LiPF ₄ C ₂ 0 ₄ (four One or more of lithium fluorooxalate phosphate.

非水有机溶剂选自碳酸酯及其! ¾代衍生物、醚、砜、腈、离子液体中的一种或几种。优选地，所述非水有机溶剂为碳酸乙烯酯（Ethylene Carbonate, 简称 EC)、碳酸丙烯酯（Propylene Carbonate, 简称 PC)、 1,2-碳酸亚乙烯酯（ VC )、二曱基碳酸酯（DMC)、碳酸二乙酯（DEC)、曱基乙基碳酸酯（EMC)、氟代碳酸乙烯酯（FEC)、 γ-丁内酯、曱基乙基醚、四氢呋喃、环丁砜、乙腈和 1-曱基 -3-乙基咪唑二 (三氟曱基横酰)亚胺中的一种或几种。 The non-aqueous organic solvent is selected from the group consisting of carbonates and their derivatives, ethers, sulfones, nitriles, ionic liquids. Preferably, the non-aqueous organic solvent is Ethylene Carbonate (EC), Propylene Carbonate (PC), 1,2-vinylene carbonate (VC), dimercaptocarbonate ( DMC), diethyl carbonate (DEC), mercaptoethyl carbonate (EMC), fluoroethylene carbonate (FEC), γ-butyrolactone, mercaptoethyl ether, tetrahydrofuran, sulfolane, acetonitrile and 1-曱 One or more of -3-ethylimidazolium bis(trifluoroindolyl) amide.

优选地，按质量分数计，非水有机高电压电解液添加剂占非水有机高电压电解液的 0.1~10%。 Preferably, the non-aqueous organic high-voltage electrolyte additive accounts for 0.1 to 10% of the non-aqueous organic high-voltage electrolyte solution by mass fraction.

本发明实施例第二方面提供的一种非水有机高电压电解液含有上述非水有机高电压电解液添加剂，因此能够满足 4.5V及以上高电压锂离子二次电池用，具有优异的电化学稳定性，可避免高电压下锂离子二次电池产气膨胀的现象，以及提高高电压下锂离子二次电池的循环性能和放电容量。 The non-aqueous organic high-voltage electrolyte provided by the second aspect of the present invention contains the above-mentioned non-aqueous organic high-voltage electrolyte additive, and thus can satisfy the high-voltage lithium ion secondary battery of 4.5 V or higher, and has excellent electrochemistry. The stability can avoid the phenomenon of gas expansion of the lithium ion secondary battery under high voltage, and improve the cycle performance and discharge capacity of the lithium ion secondary battery under high voltage.

第三方面，本发明实施例提供了一种锂离子二次电池，包括： In a third aspect, an embodiment of the present invention provides a lithium ion secondary battery, including:

正极，正极包括能嵌入或脱出锂离子的正极活性材料； a positive electrode, the positive electrode comprising a positive active material capable of inserting or extracting lithium ions;

负极，负极包括能嵌入或脱出锂离子的负极活性材料； a negative electrode, the negative electrode comprising a negative active material capable of inserting or extracting lithium ions;

隔膜； Diaphragm

非水有机高电压电解液，包括：锂盐、非水有机溶剂和非水有机高电压电解液添加剂，所述非水有机高电压电解液添加剂的化学结构式如式（ I )所示： The non-aqueous organic high-voltage electrolyte comprises: a lithium salt, a non-aqueous organic solvent and a non-aqueous organic high-voltage electrolytic solution additive, and the chemical structural formula of the non-aqueous organic high-voltage electrolyte additive is as shown in the formula (I):

C_P eHⁿ2e+l- F_f 式（ I )，其中， R_a、 R_b、 R_c和 R_d为氧或有机基团，所述有机基团包括烷基、烯烃基、炔烃基、芳香基、卤代烷基、卤代烯烃基、卤代炔烃基和卤代芳香基中的一种; 其中 i、 j、 q和 t为 0或 1 ; x、 n、 e和 h为 1 ~ 4的整数， f为 0 ~ (2e+l)的整数， k为 0 ~ (2h+l)的整数， m为 0 ~ (2n+l)的整数， y为 0 ~ (2x+l)的整数。所述非水有机高电压电解液如本发明实施例第二方面所述，此处不再赘述。本发明实施例第三方面提供的锂离子二次电池具有良好的循环性能和放电容量。 C _P eH ⁿ 2e+l- F _{f is a} formula (I), wherein R _a , R _b , R _c and R _d are an oxygen or an organic group, and the organic group includes an alkyl group, an alkene group, an alkyne group, One of an aryl group, a haloalkyl group, a halogenated alkene group, a halogenated alkyne group, and a halogenated aryl group; wherein i, j, q, and t are 0 or 1; x, n, e, and h are 1 to 4 An integer, f is an integer from 0 to (2e+l), k is an integer from 0 to (2h+l), m is an integer from 0 to (2n+l), and y is an integer from 0 to (2x+l). The non-aqueous organic high-voltage electrolyte is as described in the second aspect of the embodiment of the present invention, and details are not described herein again. The lithium ion secondary battery provided by the third aspect of the embodiment of the present invention has good cycle performance and discharge capacity.

本发明实施例第一方面提供的一种非水有机高电压电解液添加剂可用在锂离子二次电池的制备中，锂离子二次电池在的充电过程中，正极电位不断升高，该非水有机高电压电解液添加剂将促进正极材料表面保护膜的形成；保护膜会覆盖正极材料表面的活性位点，阻断正极材料表面上活性位点与非水有机电解液的直接接触，抑制正极材料对非水有机电解液的氧化作用，解决了现有技术中的非水有机电解液在高电压（4.5V 以上电压）电池体系中易与正极材料发生持续副反应导致锂离子二次电池循环性能下降、体积膨胀以及放电容量下降的问题。本发明实施例第二方面提供的一种非水有机高电压电解液含有上述非水有机高电压电解液添加剂，因此能够满足 4.5V及以上高电压锂离子二次电池用，具有优异的电化学稳定性，可避免高电压下锂离子二次电池产气膨胀的现象。本发明实施例第三方面提供的锂离子二次电池具有良好的循环性能和放电容量。附图说明 A non-aqueous organic high-voltage electrolyte additive provided by the first aspect of the present invention can be used in the preparation of a lithium ion secondary battery. During the charging process of the lithium ion secondary battery, the positive electrode potential is continuously increased, and the non-aqueous The organic high-voltage electrolyte additive will promote the formation of a protective film on the surface of the positive electrode material; the protective film covers the active site on the surface of the positive electrode material, blocks the direct contact between the active site on the surface of the positive electrode material and the non-aqueous organic electrolyte, and suppresses the positive electrode material. The oxidation of the non-aqueous organic electrolyte solves the problem that the non-aqueous organic electrolyte in the prior art is prone to continuous side reaction with the positive electrode material in the high voltage (voltage above 4.5V) battery system, resulting in the cycle performance of the lithium ion secondary battery. The problem of falling, volume expansion, and decreased discharge capacity. A non-aqueous organic high-voltage electrolyte provided by the second aspect of the present invention contains the above-mentioned non-aqueous organic high-voltage electrolyte additive, and thus can satisfy a high-voltage lithium ion secondary battery of 4.5 V or higher, and has excellent electrochemistry. Stability, can avoid the phenomenon of gas expansion of lithium ion secondary battery under high voltage. The lithium ion secondary battery provided by the third aspect of the embodiment of the present invention has good cycle performance and discharge capacity. DRAWINGS

图 1为实施例一〜五和对比实施例中制得的锂离子二次电池在 3.5 ~ 4.9V电位区间范围内室温条件下进行充放电循环结果图。具体实施方式 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a graph showing the results of charge and discharge cycles of a lithium ion secondary battery obtained in Examples 1 to 5 and Comparative Examples under a room temperature range of 3.5 to 4.9 V. detailed description

以下所述是本发明实施例的优选实施方式，应当指出，对于本技术领域的普通技术人员来说，在不脱离本发明实施例原理的前提下，还可以做出若干改进和润饰，这些改进和润饰也视为本发明实施例的保护范围。 The following is a preferred embodiment of the embodiments of the present invention. It should be noted that those skilled in the art can make some modifications without departing from the principles of the embodiments of the present invention. These improvements and retouchings are also considered to be within the scope of protection of embodiments of the present invention.

本发明实施例第一方面旨在提供一种非水有机高电压电解液添加剂，该非水有机高电压电解液添加剂在高电压锂离子二次电池的充电过程中被氧化分解，促进正极材料表面保护膜的形成，抑制正极材料对非水有机电解液的氧化作用，本发明实施例第二方面旨在提供一种包含上述非水有机电解液添加剂的非水有机电解液，该非水有机高电压电解液能够满足 4.5V及以上高电压锂离子二次电池用。本发明实施例第三方面旨在提供一种包含上述非水有机高电压电解液的锂离子二次电池，该锂离子二次电池在高电压下具有较好的循环性能和放电容量。 A first aspect of the embodiments of the present invention is directed to providing a non-aqueous organic high-voltage electrolyte additive which is oxidatively decomposed during charging of a high-voltage lithium ion secondary battery to promote the surface of the positive electrode material. The formation of the protective film inhibits the oxidation of the positive electrode material to the non-aqueous organic electrolyte. The second aspect of the present invention is directed to providing a non-aqueous organic electrolyte containing the non-aqueous organic electrolyte additive. The voltage electrolyte can meet the high voltage lithium ion secondary battery of 4.5V and above. A third aspect of the embodiment of the present invention is directed to a lithium ion secondary battery comprising the above nonaqueous organic high voltage electrolytic solution, which has good cycle performance and discharge capacity at a high voltage.

^Ce^H2e+l-f^Ff 式 ( I )，其中， R_a、 R_b、 R_c和 R_d为氧或有机基团，所述有机基团包括烷基、烯烃基、炔烃基、芳香基、卤代烷基、卤代烯烃基、卤代炔烃基和卤代芳香基中的一种；其中 i、 j、 q和 t为 0或 1 ; x、 n、 e和 h为 1 ~ 4的整数， f为 0 ~ (2e+l)的整数， k为 0 ~ (2h+l)的整数， m为 0 ~ (2n+l)的整数， y为 0 ~ (2x+l)的整数。 ^C e ^H 2e+lf ^F f Formula (I), wherein R _a , R _b , R _c and R _d are an oxygen or an organic group, and the organic group includes an alkyl group, an alkene group, an alkyne group, an aromatic group And one of a haloalkyl group, a halogenated alkene group, a halogenated alkyne group and a halogenated aryl group; wherein i, j, q and t are 0 or 1; x, n, e and h are integers of 1 to 4, f is an integer from 0 to (2e+l), k is an integer from 0 to (2h+l), m is an integer from 0 to (2n+l), and y is an integer from 0 to (2x+l).

优选地，所述 R_a、 R_b、 R_c和 R_d为氧、碳原子数为 1 ~ 8的烷基、碳原子数为 2 ~ 8的烯烃基、碳原子数为 2 ~ 8的炔烃基、碳原子数为 6 ~ 8的芳香基、碳原子数为 1 ~ 8的卤代烷基、碳原子数为 2 ~ 8的卤代烯烃基、碳原子数为 2 ~ 8 的卤代炔烃基或碳原子数为 6 ~ 8的卤代芳香基。 Preferably, the R _a , R _b , R _c and R _d are oxygen, an alkyl group having 1 to 8 carbon atoms, an alkene group having 2 to 8 carbon atoms, and an alkyne having 2 to 8 carbon atoms. Hydrocarbyl group, aromatic group having 6-8 carbon atoms, carbon A halogenated alkyl group having 1 to 8 atoms, a halogenated alkene group having 2 to 8 carbon atoms, a halogenated alkyne group having 2 to 8 carbon atoms or a halogenated aromatic group having 6 to 8 carbon atoms.

I a、

I b、

I f。

I a,

I b,

I f.

本发明实施例第一方面提供的一种非水有机高电压电解液添加剂可用在锂离子二次电池的制备中，锂离子二次电池在充电过程中，正极电位不断升高，高电压添加剂会促进正极材料表面保护膜的形成，保护膜覆盖正极材料表面的活性位点，阻断正极材料表面上活性位点与非水有机电解液的直接接触，抑制正极材料对非水有机电解液的氧化作用，避免锂离子二次电池体积膨胀以及放电容量下降的情况，从而提高高电压下锂离子二次电池的循环性能和放电容量。 A non-aqueous organic high-voltage electrolyte additive provided by the first aspect of the present invention can be used in the preparation of a lithium ion secondary battery. During the charging process of the lithium ion secondary battery, the positive electrode potential is continuously increased, and the high-voltage additive will be Promoting the formation of a protective film on the surface of the positive electrode material, the protective film covering the surface of the positive electrode material The active site blocks the direct contact between the active site on the surface of the positive electrode material and the non-aqueous organic electrolyte, inhibits the oxidation of the positive electrode material to the non-aqueous organic electrolyte, and avoids the volume expansion of the lithium ion secondary battery and the decrease of the discharge capacity. Thereby, the cycle performance and discharge capacity of the lithium ion secondary battery at a high voltage are improved.

优选地，所述 R_a、 R_b、 R_c和 R_d为碳原子数为 2 ~ 6的烷基、碳原子数为 2 ~ 6的烯烃基、碳原子数为 2 ~ 6的炔烃基、碳原子数为 2 ~ 6的卤代烷基、碳原子数为 2 ~ 6的卤代烯烃基和碳原子数为 2 ~ 6的卤代炔烃基中的一种。优选地，所述非水有机高电压电解液添加剂的化学结构式为式 I a 的一种：Preferably, the R _a , R _b , R _c and R _d are an alkyl group having 2 to 6 carbon atoms, an olefin group having 2 to 6 carbon atoms, an alkyne group having 2 to 6 carbon atoms, One of a halogenated alkyl group having 2 to 6 carbon atoms, a halogenated alkene group having 2 to 6 carbon atoms, and a halogenated alkyne group having 2 to 6 carbon atoms. Preferably, the non-aqueous organic high voltage electrolyte additive has a chemical structural formula of one of the formulas I a:

Ic、

I f。

Ic,

I f.

其中，锂盐选自 LiPF₆、 LiBF₄、 LiC10₄、 Li ( CF₃S0₂ ) ₂N、 LiBOB (双草酸硼酸锂）、 LiDFOB (二氟草酸硼酸锂 )和 LiPF₄C₂0₄ (四氟草酸磷酸锂）中的一种或几种。优选地，锂盐在非水有机电解液中的终浓度为 0.1~1.5mol/L。 Wherein, the lithium salt is selected from the group consisting of LiPF ₆ , LiBF ₄ , LiC10 ₄ , Li ( CF ₃ S0 ₂ ) ₂ N, LiBOB (lithium bis(oxalate) borate), LiDFOB (lithium difluorooxalate borate), and LiPF ₄ C ₂ 0 ₄ (four One or more of lithium fluorooxalate phosphate. Preferably, the final concentration of the lithium salt in the non-aqueous organic electrolyte is from 0.1 to 1.5 mol/L.

非水有机溶剂选自碳酸酯及其! ¾代衍生物、醚、砜、腈、离子液体中的一种或几种。优选地，所述非水有机溶剂为碳酸乙烯酯（Ethylene Carbonate, 简称 EC )、碳酸丙烯酯（Propylene Carbonate, 简称 PC )、 1,2-碳酸亚乙烯酯（ VC )、二曱基碳酸酯（DMC )、碳酸二乙酯（DEC )、曱基乙基碳酸酯（EMC )、氟代碳酸乙烯酯（FEC )、 γ-丁内酯、曱基乙基醚、四氢呋喃、环丁砜、乙腈或 1-曱基 -3-乙基咪唑二 (三氟曱基横酰)亚胺中的一种或几种。 The non-aqueous organic solvent is selected from the group consisting of carbonates and their derivatives, ethers, sulfones, nitriles, ionic liquids. Preferably, the non-aqueous organic solvent is Ethylene Carbonate (EC), Propylene Carbonate (PC), 1,2-vinylene carbonate (VC), dimercaptocarbonate ( DMC), diethyl carbonate (DEC), mercaptoethyl carbonate (EMC), fluoroethylene carbonate (FEC), γ-butyrolactone, mercaptoethyl ether, tetrahydrofuran, sulfolane, acetonitrile or 1-曱 One or more of -3-ethylimidazolium bis(trifluoroindolyl) amide.

更优选地，按质量分数计，非水有机高电压电解液添加剂占非水有机高电压电解液的 0.5~8%。 More preferably, the non-aqueous organic high-voltage electrolyte additive accounts for 0.5 to 8% of the non-aqueous organic high-voltage electrolyte in terms of mass fraction.

为了满足非水有机高电压电解液在特定情形下的应用需求，优选地，非水有机高电压电解液还包括功能助剂，所述功能助剂为高温添加剂、阻燃添加剂或过充添力口剂。 In order to meet the application requirements of the non-aqueous organic high-voltage electrolyte in a specific situation, preferably, the non-aqueous organic high-voltage electrolyte further includes a functional auxiliary agent, which is a high-temperature additive, a flame retardant additive or an overcharged force. Oral agent.

优选地，所述高温添加剂选自 1， 3丙横酸内酯、氟代碳酸乙烯脂 (FEC)和四氟硼酸锂 (LiBF₄)中的一种或几种，所述阻燃添加剂选自磷酸三曱酯、磷酸三乙酯、磷酸三苯酯、磷酸三丁酯和磷腈类化合物中的一种或几种，所述过充添加剂选自联苯和环己基苯中的一种或几种。 Preferably, the high temperature additive is selected from one or more of 1,3 propionate, fluoroethylene carbonate (FEC) and lithium tetrafluoroborate (LiBF ₄ ), and the flame retardant additive is selected from the group consisting of One or more of tridecyl phosphate, triethyl phosphate, triphenyl phosphate, tributyl phosphate and phosphazene, the overcharge additive being selected from one of biphenyl and cyclohexylbenzene or Several.

更优选地，按质量分数计，功能助剂占非水有机高电压电解液的 0.1~10%。本发明实施例第二方面提供的一种非水有机高电压电解液含有上述非水有机高电压电解液添加剂，因此能够满足 4.5V及以上高电压锂离子二次电池用，具有优异的电化学稳定性，可避免高电压下锂离子二次电池产气膨胀的现象，以及提高高电压下锂离子二次电池的循环性能和放电容量。 More preferably, the functional additive accounts for 0.1 to 10% of the non-aqueous organic high-voltage electrolyte in terms of mass fraction. The non-aqueous organic high-voltage electrolyte provided by the second aspect of the present invention contains the above-mentioned non-aqueous organic high-voltage electrolyte additive, and thus can satisfy the high-voltage lithium ion secondary battery of 4.5 V or higher, and has excellent electrochemistry. The stability can avoid the phenomenon of gas expansion of the lithium ion secondary battery under high voltage, and improve the cycle performance and discharge capacity of the lithium ion secondary battery under high voltage.

隔膜； Diaphragm

非水有机高电压电解液，包括：锂盐、非水有机溶剂和非水有机高电压电解液添加剂，所述非水有机高电压电解液添加剂的化学结构式如式（ I )所示：

（ I )，其中， R_a、 R_b、 R_c和 R_d为氧或有机基团，所述有机基团包括烷基、烯烃基、炔烃基、芳香基、卤代烷基、卤代烯烃基、卤代炔烃基和卤代芳香基中的一种；其中 i、 j、 q和 t为 0或 1 ; x、 n、 e和 h为 1 ~ 4的整数， f为 0 ~ (2e+l)的整数， k为 0 ~ (2h+l)的整数， m为 0 ~ (2n+l)的整数， y为 0 ~ (2x+l)的整数。 The non-aqueous organic high-voltage electrolyte comprises: a lithium salt, a non-aqueous organic solvent and a non-aqueous organic high-voltage electrolyte additive, and the chemical structural formula of the non-aqueous organic high-voltage electrolyte additive is as shown in the formula (I):

所述非水有机高电压电解液如本发明实施例第二方面所述，此处不再赘述。优选地，所述正极活性材料的充放电脱嵌锂离子时具有 4.5V及 4.5V以上电压平台。更优选地，所述正极活性材料选自 LiCoP0₄、 LiNiP0₄、和 LiMn NiasC 中的一种或几种。 The non-aqueous organic high-voltage electrolyte is as described in the second aspect of the embodiment of the present invention, and details are not described herein again. Preferably, the positive electrode active material has a voltage platform of 4.5 V and 4.5 V or more when charged and discharged by lithium ion. More preferably, the positive active material is selected from one or more of LiCoP0 ₄ , LiNiP0 ₄ , and LiMn NiasC.

本发明实施例第三方面提供的一种锂离子二次电池的形式不限，可以为方形、圓柱或软包电池，无论是卷绕式还是叠片式，该锂离子二次电池具有良好的循环性能和放电容量。 The lithium ion secondary battery provided in the third aspect of the embodiment of the present invention is not limited in form, and may be a square, cylindrical or soft pack battery. The lithium ion secondary battery has good performance whether it is wound or laminated. Cycle performance and discharge capacity.

该锂离子二次电池的制备方法为：将正极、负极和隔膜制成电池极芯，注入所述非水有机高电压电解液，得到锂离子二次电池。所述锂离子二次电池的制备方法简易可行。 The lithium ion secondary battery is prepared by forming a positive electrode, a negative electrode, and a separator into a battery core, and injecting the non-aqueous organic high-voltage electrolyte to obtain a lithium ion secondary battery. The preparation method of the lithium ion secondary battery is simple and feasible.

本发明实施例的优点将会在下面的说明书中部分阐明，一部分根据说明书是显而易见的，或者可以通过本发明实施例的实施而获知。实施例一 The advantages of the embodiments of the present invention will be set forth in part in the description which follows. Embodiment 1

一种非水有机高电压电解液添加剂的制备方法，包括以下步骤： A method for preparing a non-aqueous organic high-voltage electrolyte additive comprises the following steps:

在充满高纯氩气的手套箱中，取六氟异丙醇，加入盛有无水四氢呋喃（THF ) 的烧瓶中（装满五分之二烧瓶），用橡胶塞封后转出手套箱。将烧瓶转入冰浴中，在氮气气氛保护下，用长针头吸取化学计量比的正丁基锂 /正己烷溶液，并緩慢加入盛有六氟异丙醇和 THF的混合溶液中。整个反应过程强搅拌、充氮气保护，反应约 12小时后停止。然后用长针头吸取四氯硅烷溶液（SiCl₄ )，緩慢加入第一步反应后的混合溶液烧瓶中，六氟异丙醇和四氯硅烷的摩尔比为 4: 1，反应在室温条件下氮气保护进行约 24小时后反应停止。待整个反应过程结束后，用砂型漏斗过滤，除去反应副产物滤渣（LiCl )，回收滤液。用旋转蒸发仪除去烧瓶中残余的反应溶剂包括四氢呋喃和正己烷，浓缩反应产物。随后，将得到的浓缩产物转入小号烧瓶中，连接升华器，并连通循环冷凝水。通过油浴加热，在减压条件下可以得到目标产物晶体。将得到固体产物回收，在 110°C真空干燥 12 小时以上并储存于高纯氩气手套箱中待用，得到 l a所示的非水有机高电压电解液添加剂硅酸-四-六氟异丙基酯。 In a glove box filled with high purity argon, hexafluoroisopropanol was added to a flask containing anhydrous tetrahydrofuran (THF) (filled with two-fifths of the flask), sealed with a rubber stopper and transferred out of the glove box. The flask was transferred to an ice bath, and under a nitrogen atmosphere, a stoichiometric ratio of n-butyllithium/n-hexane solution was taken up with a long needle, and a mixed solution containing hexafluoroisopropanol and THF was slowly added. The whole reaction process was vigorously stirred and nitrogen-filled, and the reaction was stopped after about 12 hours. Then, the tetrachlorosilane solution (SiCl ₄ ) was taken up with a long needle, and the mixed solution flask after the first step reaction was slowly added. The molar ratio of hexafluoroisopropanol to tetrachlorosilane was 4:1. The reaction was nitrogen-protected at room temperature. The reaction was stopped after about 24 hours. After the completion of the entire reaction process, the mixture was filtered through a sand funnel to remove reaction by-product residue (LiCl), and the filtrate was recovered. The residual reaction solvent in the flask was removed by a rotary evaporator, including tetrahydrofuran and n-hexane, and the reaction product was concentrated. Subsequently, the obtained concentrated product was transferred to a small flask, connected to a sublimator, and connected to circulating condensed water. The target product crystals can be obtained under reduced pressure by heating in an oil bath. The solid product was recovered, dried under vacuum at 110 ° C for more than 12 hours, and stored in a high-purity argon glove box for use, to obtain a non-aqueous organic high-voltage electrolyte additive such as la-silicic acid-tetra-hexafluoroisopropyl Base ester.

一种非水有机高电压电解液的制备方法，包括以下步骤： A preparation method of a non-aqueous organic high-voltage electrolyte, comprising the following steps:

将锂盐 LiPF₆溶于非水有机溶剂中得到 lmol/L的锂盐溶液，搅拌，搅拌温度为 28°C，非水有机溶剂为碳酸乙烯酯（EC )和碳酸二曱酯（DMC )按体积比为 1 :2的比例混合而成的混合溶剂； Dissolving lithium salt LiPF ₆ in a non-aqueous organic solvent to obtain a 1 mol/L lithium salt solution, stirring, stirring temperature The degree of 28 ° C, the non-aqueous organic solvent is a mixed solvent of ethylene carbonate (EC) and dinonyl carbonate (DMC) in a ratio of 1:2 by volume;

向锂盐溶液加入如式 I a所示的非水有机高电压电解液添加剂硅酸-四 -六氟异丙基酯，搅拌，制得非水有机电解液 A，按质量分数计，非水有机高电压电解液添加剂 I a占非水有机电解液的 0.5%。 Adding the non-aqueous organic high-voltage electrolyte additive silicate-tetra-hexafluoroisopropyl ester as shown in Formula I a to the lithium salt solution, and stirring to obtain a non-aqueous organic electrolyte A, which is non-aqueous by mass fraction. The organic high voltage electrolyte additive I a accounts for 0.5% of the non-aqueous organic electrolyte.

下面以方形卷绕式锂离子二次软包电池（型号为 423450-800mAh ) 的制作为例，对本发明实施例锂离子二次电池的制备方法进行说明。 Hereinafter, a method for preparing a lithium ion secondary battery according to an embodiment of the present invention will be described by taking a production of a square-wound lithium ion secondary soft pack battery (model number 423450-800 mAh) as an example.

正极片的制备 Preparation of positive electrode sheet

本发明实施例选用的正极活性材料是 LiMn Nio.sO 将分散好的正极活性材料、导电剂炭黑粉末材料和粘结剂 PVDF按照质量比 96:2:2进行混合，然后加入 N-曱基吡咯烷酮（NMP )溶液制备成油系浆料，最后将浆料涂覆在铝集流体两面，制成锂离子二次电池正极片。 The positive electrode active material selected in the embodiment of the present invention is LiMn Nio.sO. The dispersed positive electrode active material, the conductive agent carbon black powder material and the binder PVDF are mixed according to a mass ratio of 96:2:2, and then N-fluorenyl group is added. The pyrrolidone (NMP) solution was prepared into an oil-based slurry, and finally the slurry was coated on both sides of the aluminum current collector to prepare a positive electrode sheet of a lithium ion secondary battery.

负极片的制备 Preparation of negative electrode sheets

将负极活性材料人造石墨粉末、粘结剂羧曱基纤维素（CMC )、粘结剂苯乙烯丁二烯橡胶 ( SB )乳液按照质量比 97:1.5:1.5进行混合，然后加入去离子水制备成水系负极浆料，最后将浆料涂覆在铜集流体两面，制成锂离子二次电池负极片，负极片容量设计为正极片容量的 1.2倍。 The negative active material artificial graphite powder, the binder carboxymethyl cellulose (CMC), the binder styrene butadiene rubber (SB) emulsion are mixed according to a mass ratio of 97:1.5:1.5, and then deionized water is added for preparation. The water-based negative electrode slurry was finally coated on both sides of the copper current collector to form a lithium ion secondary battery negative electrode sheet, and the negative electrode sheet capacity was designed to be 1.2 times the capacity of the positive electrode sheet.

非水有机高电压电解液釆用本发明实施例前文制得的非水有机高电压电解液 A。 The non-aqueous organic high-voltage electrolyte 釆 uses the non-aqueous organic high-voltage electrolytic solution A prepared in the foregoing embodiment of the present invention.

锂离子二次电池的制作 Production of lithium ion secondary battery

将聚丙烯和聚乙烯组成的复合隔膜放入上述制备的正极极片和负极极片之间，如三明治结构，然后一起卷制成 423450方型电池极芯，最后完成方形卷绕软包电池，最后注入非水有机高电压电解液 A，得到锂离子二次电池 A。对于锂离子二次电池，无论是方形还是圓柱或软包电池，也无论是卷绕式还是叠片式，釆用上述锂离子二次电池制备方法都能取得相同的效果。实施例二 A composite separator composed of polypropylene and polyethylene is placed between the positive electrode tab and the negative electrode tab prepared above, such as a sandwich structure, and then rolled together into a 423450 square battery pole core, and finally a square-wound soft pack battery is completed. Finally, the non-aqueous organic high-voltage electrolyte A was injected to obtain a lithium ion secondary battery A. For the lithium ion secondary battery, whether it is a square or a cylindrical or soft pack battery, whether it is a wound type or a laminated type, the same effect can be obtained by the above-described lithium ion secondary battery preparation method. Embodiment 2

在充满高纯氩气的手套箱中，取高氟叔丁醇，加入盛有无水四氢呋喃（THF ) 的烧瓶中（装满烧瓶五分之二），用橡胶塞封后转出手套箱。将烧瓶转入冰浴中，在氮气气氛保护下，用长针头吸取化学计量比的正丁基锂 /正己烷溶液，并緩慢加入盛有高氟叔丁醇和 THF的混合溶液中。整个反应过程强搅拌、充氮气保护，反应约 12小时后停止。然后用长针头吸取四氯硅烷溶液（SiCl₄ )，緩慢加入第一步反应后的混合溶液烧瓶中，高氟叔丁醇和四氯硅烷的摩尔比为 4： 1，反应在室温条件下氮气保护进行约 24小时后反应停止。待整个反应过程结束后，用砂型漏斗过滤，除去反应副产物滤渣（LiCl )，回收滤液。用旋转蒸发仪除去烧瓶中残余的反应溶剂包括四氢呋喃和正己烷，浓缩反应产物。随后，将得到的浓缩产物转入小号烧瓶中，连接升华器，并连通循环冷凝水。通过油浴加热，在减压条件下可以得到目标产物晶体。将得到固体产物回收，在 110°C真空干燥 12 小时以上并储存于高纯氩气手套箱中待用，得到 l b所示的非水有机高电压电解液添加剂硅酸 -四-高氟叔丁酯。

In a glove box filled with high purity argon, high fluoro-tert-butanol was added to a flask containing anhydrous tetrahydrofuran (THF) (filled two-fifths of the flask), sealed with a rubber stopper and transferred out of the glove box. The flask was transferred to an ice bath, and under a nitrogen atmosphere, a stoichiometric ratio of n-butyllithium/n-hexane solution was taken up with a long needle, and a mixed solution containing high-fluoro-tert-butanol and THF was slowly added. The whole reaction process was vigorously stirred and nitrogen-filled, and the reaction was stopped after about 12 hours. Then, the tetrachlorosilane solution (SiCl ₄ ) was taken up with a long needle, and slowly added to the mixed solution flask after the first step reaction, the molar ratio of high fluorine t-butanol to tetrachlorosilane was 4:1, and the reaction was nitrogen-protected at room temperature. The reaction was stopped after about 24 hours. After the completion of the entire reaction process, the mixture was filtered through a sand funnel to remove reaction by-product residue (LiCl), and the filtrate was recovered. The residual reaction solvent in the flask was removed by a rotary evaporator, including tetrahydrofuran and n-hexane, and the reaction product was concentrated. Subsequently, the obtained concentrated product was transferred to a small flask, connected to a sublimator, and connected to circulating condensed water. The target product crystals can be obtained under reduced pressure by heating in an oil bath. The solid product is recovered, dried under vacuum at 110 ° C for more than 12 hours and stored in a high-purity argon glove box for use, to obtain a non-aqueous organic high-voltage electrolyte additive represented by lb of silicic acid-tetra-high-fluorine tert-butyl ester.

将锂盐 LiPF₆溶于非水有机溶剂中得到 lmol/L的锂盐溶液，搅拌，搅拌温度为 28°C，非水有机溶剂为碳酸乙烯酯（EC )和碳酸二曱酯（DMC )按体积比为 1 :2的比例混合而成的混合溶剂； The lithium salt LiPF _{6 is} dissolved in a non-aqueous organic solvent to obtain a 1 mol/L lithium salt solution, stirred, and the stirring temperature is 28 ° C. The non-aqueous organic solvent is ethylene carbonate (EC) and diterpene carbonate (DMC). a mixed solvent in which the volume ratio is 1:2;

向锂盐溶液中加入如式 l b所示的非水有机高电压电解液添加剂硅酸-四-高氟叔丁酯，搅拌，制得非水有机电解液 B，按质量分数计，非水有机高电压电解液添加剂 l b占非水有机电解液添加剂的 1%。 Adding a non-aqueous organic high-voltage electrolyte additive silicate-tetra-fluoro-tert-butyl ester as shown in Formula 1b to the lithium salt solution, and stirring to obtain a non-aqueous organic electrolyte B, which is non-aqueous organic by mass fraction. The high voltage electrolyte additive lb accounts for 1% of the non-aqueous organic electrolyte additive.

正极片的制备 Preparation of positive electrode sheet

将正极活性材料 LiMn Nio.sO^ 导电剂炭黑粉末材料和粘结剂 PVDF粉末材料再按照质量比 96:2:2进行混合，然后加入 N-曱基吡咯烷酮（NMP )溶液制备成油系浆料，最后将浆料涂覆在铝集流体两面，制成锂离子二次电池正极片。 The positive active material LiMn Nio.sO^ conductive agent carbon black powder material and the binder PVDF powder material are further mixed according to a mass ratio of 96:2:2, and then N-mercaptopyrrolidone (NMP) solution is added to prepare an oil-based slurry. Finally, the slurry was coated on both sides of the aluminum current collector to form a positive electrode sheet of a lithium ion secondary battery.

其它按同实施例一的锂离子二次电池的制作方法，制得锂离子二次电池 B。实施例三 In the other method for producing a lithium ion secondary battery according to the first embodiment, a lithium ion secondary battery B was obtained. Embodiment 3

本实施例的非水有机高电压电解液添加剂的制备方法与实施例二相同；将实施例二中的四氯硅烷换成正己基三氯化硅，制得 I c所示的非水有机高电压电解液添加剂正己基 -三-高氟叔丁氧基硅烷，其中，高氟叔丁醇和正己基三氯化硅的摩尔比为 3:1 ,

一种非水有机高电压电解液的制备方法，包括以下步骤： The preparation method of the non-aqueous organic high-voltage electrolyte additive of the present embodiment is the same as that of the second embodiment; the tetrachlorosilane in the second embodiment is replaced by n-hexyltrichloride, and the non-aqueous organic high represented by I c is obtained. The voltage electrolyte additive is n-hexyl-tri-perfluoro-tert-butoxysilane, wherein the molar ratio of high fluorine tert-butanol to n-hexyltrichloride is 3:1,

A preparation method of a non-aqueous organic high-voltage electrolyte, comprising the following steps:

将锂盐 LiDFOB溶于非水有机溶剂中得到 lmol/L的锂盐溶液，搅拌，搅拌温度为 20°C，非水有机溶剂为碳酸乙烯酯（EC )、碳酸丙烯酯（PC )和碳酸曱乙酯（EMC )按体积比为 2: 1:5的比例混合而成的混合溶剂； The lithium salt LiDFOB is dissolved in a non-aqueous organic solvent to obtain a 1 mol/L lithium salt solution, stirred, and the stirring temperature is 20 ° C. The non-aqueous organic solvent is ethylene carbonate (EC), propylene carbonate (PC) and cesium carbonate. a mixed solvent of ethyl ester (EMC) in a ratio of 2: 1:5 by volume;

向锂盐溶液中加入如式 I c所示的非水有机高电压电解液添加剂正己基-三- 高氟叔丁氧基硅烷，搅拌，制得非水有机电解液 C，按质量分数计，非水有机高压电解液添加剂 I c占非水有机电解液的 10%。 Adding non-aqueous organic high-voltage electrolyte additive n-hexyl-tri-fluoro-tert-butoxysilane as shown in Formula Ic to the lithium salt solution, and stirring, to obtain a non-aqueous organic electrolyte C, by mass fraction, The non-aqueous organic high-pressure electrolyte additive I c accounts for 10% of the non-aqueous organic electrolyte.

按同实施例一的锂离子二次电池的制作方法，制得锂离子二次电池 C。实施例四 According to the method for producing a lithium ion secondary battery of the first embodiment, a lithium ion secondary battery C was obtained. Embodiment 4

本实施例的非水有机高电压电解液添加剂的制备方法与实施例二相同；将实施例二中的四氯化硅换成二对曱苯基二氯化硅，制得 I d所示的非水有机高电压电解液添加剂二-对曱苯基 -二-高氟叔丁氧基硅烷，其中，高氟叔丁醇和二对 The preparation method of the non-aqueous organic high-voltage electrolyte additive of the present embodiment is the same as that of the second embodiment; the silicon tetrachloride in the second embodiment is replaced by the two-ply phenyl phenyl dichloride to obtain the I d Non-aqueous organic high-voltage electrolyte additive di-p-phenylene-di-high-fluoro-tert-butoxysilane, wherein high-fluorinated tert-butanol and two pairs

将锂盐 LiPF₆和 LiDFOB溶于非水有机溶剂中得到 lmol/L的锂盐溶液， LiPF₆ 和 LiDFOB的摩尔比为 4:1，搅拌，搅拌温度为 20°C，非水有机溶剂为碳酸乙烯酯（EC )、碳酸丙烯酯（PC )和碳酸曱乙酯（EMC )按体积比为 2: 1:5的比例混合而成的混合溶剂； The lithium salt LiPF ₆ and LiDFOB are dissolved in a non-aqueous organic solvent to obtain a lithium salt solution of 1 mol/L, the molar ratio of LiPF ₆ and LiDFOB is 4:1, stirring, stirring temperature is 20 ° C, and the non-aqueous organic solvent is carbonic acid. a mixed solvent of vinyl ester (EC), propylene carbonate (PC) and cesium carbonate (EMC) in a ratio of 2: 1:5 by volume;

向锂盐溶液中加入如式 I d所示的非水有机高电压电解液添加剂，搅拌，制得非水有机电解液 D，按质量分数计，非水有机高压电解液添加剂 I d占非水有机电解液的 0.1%。 A non-aqueous organic high-voltage electrolyte additive as shown in Formula Id is added to the lithium salt solution, and stirred to obtain a non-aqueous organic electrolyte D. According to the mass fraction, the non-aqueous organic high-pressure electrolyte additive I d accounts for non-aqueous 0.1% of the organic electrolyte.

按同实施例一的锂离子二次电池的制作方法，制得锂离子二次电池 D。实施例五 According to the method for producing a lithium ion secondary battery of the first embodiment, a lithium ion secondary battery D was obtained. Embodiment 5

本实施例的非水有机高电压电解液添加剂的制备方法与实施例二相同；将实施例二中的四氯化硅换成三乙基氯化硅，制得 I e所示的非水有机高电压电解液添加剂高氟叔丁氧基-三乙基硅烷，其中，高氟叔丁醇和三乙基氯化硅的摩尔比为 1:1。

The preparation method of the non-aqueous organic high-voltage electrolyte additive of the present embodiment is the same as that of the second embodiment; the silicon tetrachloride in the second embodiment is replaced by triethyl silicon chloride to obtain the non-aqueous organic compound represented by I e The high voltage electrolyte additive is high fluorine tert-butoxy-triethylsilane, wherein the molar ratio of high fluorine tert-butanol to triethylsilyl chloride is 1:1.

将锂盐 0.8 M LiPF₆ 和 0.2 M LiBOB溶于非水有机溶剂中，得到 lmol/L的锂盐溶液， LiPF₆和 LiBOB的摩尔比为 4:1，然后搅拌，搅拌温度为 20°C，非水有机溶剂为碳酸乙烯酯（EC )和碳酸二曱酯（DMC )按体积比为 1:2的比例混合而成的混合溶剂； The lithium salt 0.8 M LiPF ₆ and 0.2 M LiBOB were dissolved in a non-aqueous organic solvent to obtain a 1 mol/L lithium salt solution, and the molar ratio of LiPF _{6 to} LiBOB was 4:1, followed by stirring, and the stirring temperature was 20 ° C. The non-aqueous organic solvent is a mixed solvent obtained by mixing ethylene carbonate (EC ) and dinonyl carbonate (DMC) in a ratio of 1:2 by volume;

向锂盐溶液中加入如式 I e所示的非水有机高电压电解液添加剂，搅拌，制得非水有机电解液 E，按质量分数计，非水有机高压电解液添加剂 I e占非水有机电解液的 3%。 A non-aqueous organic high-voltage electrolyte additive as shown in Formula Ie is added to the lithium salt solution, and stirred to obtain a non-aqueous organic electrolyte E. According to the mass fraction, the non-aqueous organic high-pressure electrolyte additive I e accounts for non-aqueous 3% of the organic electrolyte.

按同实施例一的锂离子二次电池的制作方法，制得锂离子二次电池 E。实施例六 According to the method for producing a lithium ion secondary battery of the first embodiment, a lithium ion secondary battery E was obtained. Embodiment 6

本实施例的非水有机高电压电解液添加剂的制备方法与实施例二相同；将实施例二中的四氯化硅换成十七氟癸基三氯硅烷，制得 I f所示的非水有机高电压电解液添加剂三 -高氟叔丁氧基十七氟癸基硅烷，其中，高氟叔丁醇和十七氟 The preparation method of the non-aqueous organic high-voltage electrolyte additive of the present embodiment is the same as that of the second embodiment; the silicon tetrachloride in the second embodiment is replaced with heptadecafluorodecyltrichlorosilane to obtain the non-I f Water organic high voltage electrolyte additive tri-high fluorine tert-butoxy heptadecafluorodecyl silane, wherein, high fluorine tert-butanol and heptafluorosilane

-C一 C一 C一 C一 c一 c- -C一 c- -C一 C一 C一 C一 c一 c- -C一 c-

将锂盐 0.8 M LiPF₆ 和 0.2 M LiBF₄溶于非水有机溶剂中，得到 lmol/L的锂盐溶液，然后搅拌，搅拌温度为 20°C，非水有机溶剂为碳酸乙烯酯（EC )和碳酸二曱酯（DMC )按体积比为 1:3的比例混合而成的混合溶剂； The lithium salt 0.8 M LiPF ₆ and 0.2 M LiBF _{4 are} dissolved in a non-aqueous organic solvent to obtain a 1 mol/L lithium salt solution, followed by stirring, the stirring temperature is 20 ° C, and the non-aqueous organic solvent is ethylene carbonate (EC). a mixed solvent of dicumyl carbonate (DMC) in a ratio of 1:3 by volume;

向锂盐溶液中加入如式 I f所示的非水有机高电压电解液添加剂，搅拌，制得非水有机电解液 F，按质量分数计，非水有机高压电解液添加剂 I f 占非水有机电解液的 0.5%。 A non-aqueous organic high-voltage electrolyte additive as shown in Formula If is added to the lithium salt solution, and stirred to obtain a non-aqueous organic electrolyte F. The non-aqueous organic high-pressure electrolyte additive I f accounts for non-water by mass fraction. 0.5% of the organic electrolyte.

按同实施例一的锂离子二次电池的制作方法，制得锂离子二次电池 F。对比实施例 According to the method for producing a lithium ion secondary battery of the first embodiment, a lithium ion secondary battery F was obtained. Comparative example

将锂盐 1^^₆溶于非水有机溶剂中，得到 lmol/L的锂盐溶液，搅拌，制得非水有机电解液，非水有机溶剂为碳酸乙烯酯（EC )和碳酸二曱酯（DMC )按体积比为 1:2的比例混合而成的混合溶剂。将配制好的非水有机电解液注入到已经制作好的方形卷绕式锂离子二次软包电池（型号为 423450-800mAh ) 中，记为对比实施例。 The lithium salt 1^^ _{6 is} dissolved in a non-aqueous organic solvent to obtain a 1 mol/L lithium salt solution, and stirred to obtain a non-aqueous organic electrolyte. The non-aqueous organic solvent is ethylene carbonate (EC) and dinonyl carbonate. (DMC) A mixed solvent obtained by mixing in a ratio of 1:2 by volume. The prepared non-aqueous organic electrolyte was injected into a square-wound lithium ion secondary soft pack battery (model number 423450-800 mAh) which has been prepared, and is referred to as a comparative example.

以上实施例和对比实施例中制得的锂离子二次电池为实验电池，在 3.5 ~ 4.9V电位区间范围内室温条件下进行充放电循环，测试结果如图 1所示。 The lithium ion secondary battery prepared in the above examples and comparative examples was an experimental battery, and was subjected to a charge and discharge cycle at room temperature in a range of 3.5 to 4.9 V. The test results are shown in Fig. 1.

从图 1中可以看出，添加了本发明实施例第一方面提供的非水有机电解液添加剂的锂离子二次电池性能得到明显改善，经过 16次循环后，实施例 1 ~ 5的锂离子二次电池容量基本保持不变，相比之下，对比实施例未添加非水有机电解液添加剂的锂离子二次电池在循环第五次后容量开始下降，在循环第十五次后，对比实施例中的锂离子二次电池从初始容量为 120mAh/g 下降到了 80mAh/g, 容量下降了 33.3%。这说明，本发明实施例第一方面提供的非水有机电解液添加剂改善了锂离子二次电池在高电压下的循环性能，其原因在该非水有机高电压电解液添加剂在锂离子二次电池充电过程中被氧化分解，促进正极材料表面保护膜的形成，保护膜覆盖正极材料表面的活性位点，阻断正极材料表面上活性位点与非水有机电解液的直接接触，抑制正极材料对非水有机电解液的氧化作用，避免锂离子二次电池体积膨胀以及放电容量下降的情况，从而提高高电压下锂离子二次电池的循环性能。 It can be seen from FIG. 1 that the non-aqueous organic electrolyte solution provided by the first aspect of the embodiment of the present invention is added. The performance of the additive lithium ion secondary battery was significantly improved. After 16 cycles, the capacity of the lithium ion secondary batteries of Examples 1 to 5 remained substantially unchanged, in contrast, the non-aqueous organic electrolysis was not added in the comparative example. The lithium ion secondary battery of the liquid additive began to decrease in capacity after the fifth cycle, and after the fifteenth cycle, the lithium ion secondary battery in the comparative example was reduced from an initial capacity of 120 mAh/g to 80 mAh/g, and the capacity was decreased. It fell by 33.3%. This indicates that the non-aqueous organic electrolyte additive provided by the first aspect of the present invention improves the cycle performance of the lithium ion secondary battery at a high voltage, because the non-aqueous organic high-voltage electrolyte additive is secondary to lithium ions. The battery is oxidized and decomposed during charging to promote the formation of a protective film on the surface of the positive electrode material. The protective film covers the active site on the surface of the positive electrode material, blocks the direct contact between the active site on the surface of the positive electrode material and the non-aqueous organic electrolyte, and suppresses the positive electrode material. The oxidation of the non-aqueous organic electrolyte avoids the volume expansion of the lithium ion secondary battery and the decrease in the discharge capacity, thereby improving the cycle performance of the lithium ion secondary battery at a high voltage.

Claims

权利要求 Rights request

1、一种非水有机高电压电解液添加剂，其特征在于，所述非水有机高电压电解液添加剂的化学结构式如式（ I )所示： 1. A non-aqueous organic high-voltage electrolyte additive, characterized in that the chemical structural formula of the non-aqueous organic high-voltage electrolyte additive is as shown in formula (I):

式（ I )，其中， R_a、 R_b、 R_c和 R_d为氧或有机基团，所述有机基团包括烷基、烯烃基、炔烃基、芳香基、卤代烷基、卤代烯烃基、卤代炔烃基和卤代芳香基中的一种; 其中 i、 j、 q和 t为 0或 1; x、 n、 e和 h为 1 ~4的整数， f为 0~(2e+l)的整数， k为 0 ~ (2h+l)的整数， m为 0 ~ (2n+l)的整数， y为 0 ~ (2x+l)的整数。

Formula (I), wherein R _a , R _b , R _c and R _d are oxygen or organic groups, and the organic groups include alkyl groups, alkenyl groups, alkynyl groups, aryl groups, haloalkyl groups, and haloalkenyl groups. , one of halogenated alkynyl and halogenated aromatic groups; where i, j, q and t are 0 or 1; x, n, e and h are integers from 1 to 4, f is 0~(2e+l ), k is an integer from 0 ~ (2h+l), m is an integer from 0 ~ (2n+l), y is an integer from 0 ~ (2x+l).

2、如权利要求 1所述的一种非水有机高电压电解液添加剂，其特征在于，所述 R_a、 R_b、 R_c和 R_d为氧、碳原子数为 1~8的烷基、碳原子数为 2~8的烯烃基、碳原子数为 2 ~ 8的炔烃基、碳原子数为 6 ~ 8的芳香基、碳原子数为 1 ~ 8 的卤代烷基、碳原子数为 2~8的卤代烯烃基、碳原子数为 2~8的卤代炔烃基或碳原子数为 6 ~ 8的卤代芳香基。 2. A non-aqueous organic high-voltage electrolyte additive as claimed in claim 1, wherein the Ra, _Rb _, _Rc and _Rd are oxygen and alkyl groups with 1 to 8 carbon atoms. , alkenyl group with 2 to 8 carbon atoms, alkyne group with 2 to 8 carbon atoms, aromatic group with 6 to 8 carbon atoms, halogenated alkyl group with 1 to 8 carbon atoms, 2 A halogenated alkenyl group with ∼8 carbon atoms, a halogenated alkynyl group with 2∼8 carbon atoms or a halogenated aromatic group with 6∼8 carbon atoms.

3、如权利要求 2所述的一种非水有机高电压电解液添加剂，其特征在于，所述 R_a、 R_b、 R_c和 R_d为碳原子数为 2~6的烷基、碳原子数为 2~6的烯烃基、碳原子 2 ~ 6的炔烃基、碳原子数为 2 ~ 6的卤代烷基、碳原子数为 2 ~ 6的卤代烯烃基和碳原子数为 2 ~ 6的卤代炔烃基中的一种。 3. A non-aqueous organic high-voltage electrolyte additive as claimed in claim 2, wherein the R _a , R _b , R _c and R _d are alkyl groups with 2 to 6 carbon atoms. Alkenyl group with atomic number 2~6, One of an alkyne group with 2 to 6 carbon atoms, a halogenated alkyl group with 2 to 6 carbon atoms, a halogenated alkenyl group with 2 to 6 carbon atoms, and a halogenated alkyne group with 2 to 6 carbon atoms.

4、如权利要求 1所述的一种非水有机高电压电解液添加剂，其特征在于: 所述非水有机高电压电解液 I a〜式 I f中的一种：

C、 4. A non-aqueous organic high-voltage electrolyte additive as claimed in claim 1, characterized in that: one of the non-aqueous organic high-voltage electrolyte solutions I a to formula I f:

C．

5、一种非水有机高电压电解液，其特征在于，包括：锂盐、非水有机溶剂和非水有机高电压电解液添加剂，所述非水有机高电压电解液添加剂的化学结构式如式（ I ) 所示：

式（ I )，其中， R_a、 R_b、 R_c和 R_d为氧或有机基团，所述有机基团包括烷基、烯烃基、炔烃基、芳香基、卤代烷基、卤代烯烃基、卤代炔烃基和卤代芳香基中的一种; 其中 i、 j、 q和 t为 0或 1; x、 n、 e和 h为 1 ~4的整数， f为 0~(2e+l)的整数， k为 0 ~ (2h+l)的整数， m为 0 ~ (2n+l)的整数， y为 0 ~ (2x+l)的整数。 5. A non-aqueous organic high-voltage electrolyte, characterized in that it includes: lithium salt, non-aqueous organic solvent and non-aqueous organic high-voltage electrolyte additive. The chemical structural formula of the non-aqueous organic high-voltage electrolyte additive is as follows: (I) shown:

6、如权利要求 5所述的一种非水有机高电压电解液，其特征在于，所述 R_a、 R_b、 R_c和 R_d为氧、碳原子数为 1~8的烷基、碳原子数为 2~ 8的烯烃基、碳原子数为 2 ~ 8的炔烃基、碳原子数为 6 ~ 8的芳香基、碳原子数为 1 ~ 8的卤代烷基、碳原子数为 2~8的卤代烯烃基、碳原子数为 2~8的卤代炔烃基或碳原子数为 6~8的! ¾代芳香基。 6. A non-aqueous organic high-voltage electrolyte as claimed in claim 5, characterized in that, R _a , R _b , R _c and R _d are oxygen, alkyl groups with 1 to 8 carbon atoms, Alkenyl group with 2 to 8 carbon atoms, alkyne group with 2 to 8 carbon atoms, aromatic group with 6 to 8 carbon atoms, halogenated alkyl group with 1 to 8 carbon atoms, 2 to 8 carbon atoms 8 halogenated alkenyl groups, halogenated alkynyl groups with 2 to 8 carbon atoms, or 1-generation aromatic groups with 6 to 8 carbon atoms.

7、如权利要求 6所述的一种非水有机高电压电解液，其特征在于，所述 R_a、 R_b、 R_c和 R_d为碳原子数为 2 ~ 6的烷基、碳原子数为 2 ~ 6的烯烃基、碳原子数为 2 ~ 6的炔烃基、碳原子数为 2 ~ 6的卤代烷基、碳原子数为 2 ~ 6的卤代烯烃基和碳原子数为 2 ~ 6的卤代炔烃基中的一种。 7. A non-aqueous organic high-voltage electrolyte as claimed in claim 6, wherein the Ra, _Rb _, _Rc and _Rd are alkyl groups with 2 to 6 carbon atoms, and Alkenyl groups with 2 to 6 carbon atoms, alkyne groups with 2 to 6 carbon atoms, halogenated alkyl groups with 2 to 6 carbon atoms, halogenated alkenyl groups with 2 to 6 carbon atoms, and halogenated alkenyl groups with 2 to 6 carbon atoms. One of the halogenated alkynyl groups of 6.

8、如权利要求 5所述的一种非水有机高电压电解液，其特征在于，所述非水有机 I a〜式 I f中的一种: 8. A non-aqueous organic high-voltage electrolyte as claimed in claim 5, characterized in that, the non-aqueous One of water organic I a ~ formula I f:

Ic、

Ic.

9、如权利要求 5所述的一种非水有机高电压电解液，其特征在于，按质量分数计，所述非水有机高电压电解液添加剂占非水有机电解液的 0.1~10%。 9. A non-aqueous organic high-voltage electrolyte as claimed in claim 5, characterized in that, in terms of mass fraction, the non-aqueous organic high-voltage electrolyte additive accounts for 0.1 to 10% of the non-aqueous organic electrolyte.

10、一种锂离子二次电池，其特征在于，包括： 10. A lithium-ion secondary battery, characterized in that it includes:

正极，正极包括能嵌入或脱出锂离子的正极活性材料； The positive electrode includes a positive electrode active material that can insert or extract lithium ions;

负极，负极包括能嵌入或脱出锂离子的负极活性材料； Negative electrode, the negative electrode includes a negative electrode active material that can insert or extract lithium ions;

隔膜；非水有机高电压电解液，所述非水有机高电压电解液包括：锂盐、非水有机溶剂和非水有机高电压电解液添加剂，所述非水有机高电压电解液添加剂的化学结构式如式（ I )所示： diaphragm; Non-aqueous organic high-voltage electrolyte, the non-aqueous organic high-voltage electrolyte includes: lithium salt, non-aqueous organic solvent and non-aqueous organic high-voltage electrolyte additive, the chemical structural formula of the non-aqueous organic high-voltage electrolyte additive is as follows Formula (I) is shown:

eⁿ2e+l _fF_f 式（ I )，其中， R_a、 R_b、 R_c和 R_d为氧或有机基团，所述有机基团包括烷基、烯烃基、炔烃基、芳香基、卤代烷基、卤代烯烃基、卤代炔烃基和卤代芳香基中的一种; 其中 i、 j、 q和 t为 0或 1 ; x、 n、 e和 h为 1 ~ 4的整数， f为 0 ~ (2e+l)的整数， k为 0 ~ (2h+l)的整数， m为 0 ~ (2n+l)的整数， y为 0 ~ (2x+l)的整数。 ^en 2e+l _f F _f formula (I), where R _a , R _b , R _c and R _d are oxygen or organic groups, and the organic groups include alkyl groups, alkenyl groups, alkynyl groups, and aromatic groups , one of haloalkyl, haloalkenyl, haloalkynyl and haloaromatic; where i, j, q and t are 0 or 1; x, n, e and h are integers from 1 to 4, f is an integer from 0 to (2e+l), k is an integer from 0 to (2h+l), m is an integer from 0 to (2n+l), and y is an integer from 0 to (2x+l).