Sodium ion battery

Abstract

The invention provides a sodium-ion battery, which comprises a sodium-ion battery electrolyte and a sodium-ion battery positive electrode, and the sodium-ion battery electrolyte and / or the sodium-ion battery positive electrode contain / contains a multifunctional organic matter additive, the multifunctional organic matter additive is one or more of N-hydroxysuccinimide sodium sulfonate, menadione sodium bisulfite, sodium trifluoromethanesulfinate, o-phenylmethimide sodium salt, sodium p-toluenesulfinate, sodium rose palmate, trisodium phosphinate and 2-thiophenic acid sodium salt. The multifunctional organic matter additive has the beneficial effects that the multifunctional organic matter additive has sodium supplementing and film forming effects at the same time, and the remaining multifunctional organic matter additive can also be used as electrolyte sodium salt. The multifunctional organic matter additive can improve the cycle performance of the battery at room temperature and high temperature while improving the first efficiency, the discharge capacity and the energy density of the battery, and the high temperature resistance of the sodium ion battery is improved.

Description

technical field [0001] The invention belongs to the technical field of sodium ion batteries, in particular to a sodium ion battery. Background technique [0002] Lithium-ion batteries have been widely used in portable electronic devices and electric vehicles due to their high energy density, no memory effect, and low self-discharge. Compared with lithium-ion batteries, sodium-ion batteries have the advantages of abundant sodium resources, low cost, and high safety. They are mainly used in energy storage, base stations, electric bicycles, and low-end passenger cars. However, poor reversibility of material structure phase transition, unstable electrode / electrolyte interface, formation of SEI film and some irreversible side reactions cause consumption of a certain amount of active Na at the negative electrode during charge and discharge. + , greatly reducing the energy density of SIBs. In addition, the pouch battery produces gas due to abnormal chemical reactions during the c...

AI Technical Summary

Problems solved by technology

[0007] The problem to be solved by the present invention is to provide a sodium ion battery, which can effectively solve the low utilization rate of the sodium supplement additive, the role of the sodium supplement additive is only to supplement sodium, and the remaining inactive substances remain in the electrode or dissolve during the first week of charging. Into the electrolyte, it cannot be effectively used and some residual parts will be converted into gas by electro-oxidative decomposition, which is not conducive to the safety and electrochemical performance of the battery.

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