Electrolyte additive capable of catalyzing decomposition of lithium supplement agent and application of electrolyte additive

Abstract

The invention provides an electrolyte additive capable of catalyzing decomposition of a lithium supplement agent and application thereof, the electrolyte additive capable of catalyzing decomposition of the lithium supplement agent comprises crown ether, linear ether, a nitrogen-containing polydentate coordination compound and fluorobenzene, when the electrolyte additive is applied to a battery system containing the lithium supplement agent, decomposition of the lithium supplement agent can be promoted, decomposition voltage of the lithium supplement agent can be reduced, and the lithium supplement agent can be effectively prevented from being decomposed. Meanwhile, the cycling stability of the battery can be improved.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to an electrolyte solution additive with catalytic decomposition of a lithium replenishing agent and application thereof. Background technique [0002] Lithium-ion batteries have the advantages of high energy density, high power density, and long cycle life, and are widely used in digital, electric vehicles, power tools and other fields. However, there is a loss of active lithium in lithium-ion batteries, and lithium supplementation is required. [0003] At present, lithium supplementation technology mainly includes positive electrode lithium supplementation and negative electrode lithium supplementation. The positive electrode lithium supplementation does not require additional process improvement, the cost is low, and the safety is good. However, common cathode lithium supplements such as Li 2 O 2 , Li 3 N, Li 2 C 4 O 4 , Li 2 C 2 O 4 , Li 2 C 3 O 5 and ...

AI Technical Summary

Problems solved by technology

However, common cathode lithium supplements such as Li 2 o 2 , Li 3 N. Li 2 C 4 o 4 , Li 2 C 2 o 4 , Li 2 C 3 o 5 and Li 2 C 4 o 6 The decomposition potential of the battery is relatively high (4.2-4.6V). It is necessary to charge the voltage to a higher potential during the first cycle of charging to release its capacity and exert the effect of lithium supplementation. However, at such a high voltage, it is inevitable that the positive electrode The material brings disadvantages, especially the acceleration of the side reaction between the electrolyte and the positive electrode material, the oxidative decomposition of the reducing electrolyte, and the dissolution of the transition metal of the positive electrode material.

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