Lithium battery with high safety structure

Abstract

The invention provides a positive electrode plate of a lithium battery with a high safety structure. The positive electrode plate comprises at least one of an A-type electrode, a B-type electrode or aC-type electrode, two surfaces of the A-type electrode are coated with high energy electrode materials, two surfaces of the B-type electrode are coated with high safety electrode materials, and two surfaces of the C-type electrode are coated with high energy electrode materials and high safety electrode materials. According to the lithium battery with the high safety structure, when a cell has thermal runaway, a safety function positive electrode coating surface is not involved in heat release and absorbs part of heat in the initial-stage temperature rise process of the cell. When thermal runaway cell temperature reaches safety function positive electrode decomposition caused heat release temperature and thermal runaway starts rapid expansion between electrode layers inside the cell, a safety electrode can obstruct heat transfer, prolong thermal runaway time and reduce thermal runaway outburst intensity.

Description

technical field [0001] The invention belongs to the field of lithium batteries, in particular to a lithium battery with a high safety structure. Background technique [0002] With the rapid development of the new energy vehicle market, lithium batteries have been widely used. With the promotion of new energy vehicles, people have put forward higher requirements for new energy vehicles. In order to meet the high endurance requirements, it is necessary to increase the energy density of the battery. At present, the main technical route is to use high-nickel, high-voltage positive electrode materials, silicon negative electrode materials, etc., while the high gram capacity of positive electrode materials is increased, but at the same time, the problem is the decline in thermal stability. The problem that arises is that the safety of high energy density batteries is reduced. [0003] It has been verified that the thermal runaway of lithium batteries causes fire. Generally, the...

AI Technical Summary

Problems solved by technology

The main function of the above safety measures is to avoid the occurrence of thermal runaway of the battery or to suppress the occurrence of thermal runaway and fire, and it does not solve the core problem of the transfer and accumulation of reaction heat inside the battery cell.

If the internal expansion of the thermal runaway of the battery cell is too fast, the energy inside the battery cell will burst out in a short time, which will increase the risk of thermal runaway of the lithium battery

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