A kind of bipolar sodium ion battery and preparation method thereof

Abstract

The invention relates to a bipolar sodium-ion battery and a preparation method thereof. The bipolar sodium-ion battery comprises a plurality of bipolar pole pieces, a diaphragm and an electrolyte, and a plurality of bipolar pole pieces are stacked in sequence. The bipolar pole pieces The sheet includes an aluminum foil, an insulating strip and an insulating layer. The aluminum foil has a first surface and a second surface opposite to each other. Positive electrode active layer, the negative electrode area is coated with hard carbon; the positive electrode active layer includes transition metal oxides, Prussian blue materials, polyanionic compounds or amorphous materials; the aluminum foil can be folded in half along the bending area to make the positive electrode area and negative electrode The insulating strip is arranged in the bending area; the insulating layer is interposed between the positive active layer and the hard carbon; a separator is arranged between two adjacent bipolar pole pieces; the electrolyte is used for the positive active layer and the hard carbon. Hard carbon conducts electricity, and the electrolyte includes sodium hexafluorophosphate. Bipolar sodium-ion batteries have high energy density and long service life.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a bipolar sodium ion battery and a preparation method thereof. Background technique [0002] A sodium-ion battery is a rechargeable electrochemical sodium-ion battery that mainly relies on the movement of sodium ions between the positive and negative electrodes, and uses sodium ion intercalation compounds as the positive electrode material. The material cost of sodium-ion batteries is low, and the price is more advantageous. Due to the increasing demand for energy storage, the demand for low-cost energy storage battery technology is becoming more and more urgent. The research on sodium-ion batteries has advanced by leaps and bounds in the past ten years, but the main changes in the current sodium battery industry chain In terms of positive electrode materials, the energy density and service life of sodium-ion batteries can be improved through positive electrode materials, negat...

AI Technical Summary

Problems solved by technology

However, the effect of improving the energy density and service life of sodium-ion batteries through materials is limited. Therefore, there is an urgent need for a bipolar sodium-ion battery and a preparation method thereof to improve the structure of the sodium-ion battery and combine the positive electrode material of the sodium-ion battery. , negative electrode materials and electrolyte materials to improve the energy density and service life of sodium-ion batteries

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