Contemporary Amperex Technology Co., Ltd.

Feng Huan

Changlong Han

Jianwei Zhu

Jiqiong Liu

Xiaomei Wang

Yan Zhou

Kun Yu

Xiaochong Zhou

The present invention discloses a Lithium ion battery and an electrolyte thereof, the electrolyte comprising an organic solvent, a lithium salt and an additive. The additive comprises a cyclic fluoro carbonate (A), a cyclic phosphazene (B), a cyclic sulfate and a lithium fluoro oxalate borate (D). The lithium fluoro oxalate borate (D) has following formula:  Compared with the prior art, the electrolyte of the present invention may form a stable CEI and SEI film on the surface of positive and negative electrodes, protect the interface between positive and negative electrodes, improve the acidic atmosphere of Lithium ion battery electrolyte, and reduce the damage effect of HF on the interface between positive and negative electrodes, while reducing low temperature resistance of lithium-ion battery, improving cycle life, high temperature storage performance, safety performance and rate capability of lithium-ion battery.

Lithium-ion battery and its electrolyte

The present invention discloses a Lithium ion battery and an electrolyte thereof, the electrolyte comprising an organic solvent, a lithium salt and an additive. The additive comprises additive (A) cyclic fluoro carbonate, additive (B) cyclic phosphazene (B), and additive (C) cyclic sulfate. The additive B cyclic phosphazene has the following general structural formula:  Compared with the prior art, the electrolyte of the present invention may form a stable CEI and SEI film on the surface of positive and negative electrodes, protect the interface between positive and negative electrodes, improve the acidic atmosphere of Lithium ion battery electrolyte, and reduce the damage effect of HF on the interface between positive and negative electrodes, thereby improving cycle life, high temperature storage performance, and safety performance of lithium-ion battery.

The present disclosure provides an electrolyte and a lithium-ion battery. The electrolyte comprises: an organic solvent; a lithium salt dissolved in the organic solvent; and an additive. The additive comprises trifluoromethanesulfonate silyl compound, lithium fluorophosphate compound and cyclic phosphonitrile compound. The electrolyte of the present disclosure can significantly decrease the low temperature resistance of the lithium-ion battery, and improve the power performance of the lithium-ion battery, and the electrolyte of present disclosure can also significantly inhibit the gas generation during the cycle process and the storage process of the lithium-ion battery, and significantly improve the cycle performance, the high temperature storage performance and the safety performance of the lithium-ion battery.

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Ningde, China

Feng Huan