Preparation method and application of copper-coated chromium oxide positive electrode

Abstract

The invention discloses a preparation method and application of a copper-coated chromium oxide positive electrode, and belongs to the technical field of lithium ion batteries. In order to further improve the discharge (electric) specific capacity, the dynamic process and the rate capability of the chromium oxide positive electrode material, the method comprises the following steps: carrying out high-temperature calcination, ball milling and water washing treatment on chromium trioxide to prepare a chromium oxide positive electrode; and coating the surface of the chromium oxide positive electrode with copper. According to the invention, the battery is assembled by adopting a copper-coated chromium oxide positive electrode, a single lithium ion selective diaphragm, a lithium-containing negative electrode and an ether or ester electrolytic solution; and the special electrochemical behavior of copper on one side of the positive electrode of the lithium ion battery is utilized, the Cu-Cu<2+> electrochemical reaction has a relatively high discharge voltage platform and specific capacity, and the dynamic process, the discharge capacity and the voltage platform of the positive electrode material of the battery can be remarkably improved.

Description

technical field [0001] The invention belongs to the technical field of lithium ion batteries, and in particular relates to a preparation method and application of a copper-coated chromium oxide positive electrode. Background technique [0002] With the urgent needs of small mobile electronic devices, electric vehicles and military equipment, research on rechargeable lithium-ion batteries has received extensive attention. At present, commercial lithium-ion batteries are usually based on lithium intercalation oxide (LiCoO 2 、LiFePO 4 、LiNi 0.8 co 0.1 Ni 0.1 o 2 and LiNi 0.8 co 0.15 Ni 0.05 o 2 etc.) as the positive electrode, graphite as the negative electrode, and its energy density is usually lower than 300Wh kg -1 , It is difficult to meet people's requirements for the next generation of high energy density new batteries. Among them, the positive electrode material is a key component in the structure of lithium-ion batteries, which generally directly determines k...

AI Technical Summary

Problems solved by technology

Elemental copper is often used in lithium-ion battery anode current collectors, but some special electrode materials show some special electrochemical behaviors with copper current collectors, such as metal oxides, metal sulfides and sulfur-containing positive electrodes (lithium-sulfur, magnesium-sulfur Battery) will show a significantly improved discharge voltage platform and specific capacity when copper current collectors are used, which may be caused by the chemical and electrochemical reactions of the intermediate products of the reaction between copper and electrode materials.

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