Method for improving safety performance of ternary battery

Abstract

The invention discloses a method for improving the safety performance of a ternary battery. The method comprises the following steps: (1) mixing a common cathode material with a ternary cathode material as well as lithium iron phosphate or manganese lithium iron phosphate, thereby obtaining a cathode material; (2) preparing the cathode material into the cathode of the ternary battery by use of the conventional manufacturing process of the cathode plate of a lithium-ion battery; (3) mixing graphite and a lithium titanate material and then preparing the mixture into the anode of the ternary battery by use of the conventional manufacturing process of the anode plate of the lithium-ion battery; and (4) preparing the ternary battery by use of the conventional lithium-ion battery assembly process and formation process. Compared with the prior art, the method has the beneficial effects that lithium iron phosphate and manganese lithium iron phosphate both are in an olivine structure, and the structure is very stable, and therefore, lithium iron phosphate or the manganese lithium iron phosphate at appropriate proportion can be mixed without affecting the capacity of the battery and the overall safety of the cathode material can be improved favorably. Meanwhile, the lithium titanate doped with the anode is also a compound very stable in chemical properties, and therefore, the needling safety of the ternary battery can be effectively improved.

Description

technical field [0001] The invention relates to the technical field of electrochemistry, and more specifically relates to a method for improving the safety performance of a ternary battery. Background technique [0002] As we all know, there are certain safety problems in lithium-ion batteries at present. If the manufacturing industry or conditions are not strictly controlled, safety accidents will occur. What attracted the most attention in 2006 was the large-scale recall of lithium-ion batteries for notebooks manufactured by Sony Corporation of Japan, which caused great losses, and the cost of the recall was as high as 3 billion US dollars. In order to improve the safety performance of lithium-ion batteries, the main method at present is: add flame-retardant additives (referring to Wu Yuping, " lithium-ion batteries-application and practice " chapter 9 in electrolytic solution, non-aqueous liquid electrolyte, 2004, Beijing, published by Chemical Industry Press). Although...

AI Technical Summary

Problems solved by technology

However, in actual experiments, although the ternary battery made of ternary materials meets the requirements in terms of energy density and cycle, it is prone to fire and explosion in safety performance tests, especially acupuncture tests, and cannot pass Safety performance testing limits its large-scale application in power batteries