Method for prolonging the storage time of lithium battery and lithium battery positive electrode material

Abstract

The invention provides a method for prolonging the storage time of a lithium battery and a lithium battery positive electrode material. In the method, under the condition of no change of the conventional negative electrode, lithium iron phosphate is added into the conventional lithium battery positive electrode material. The lithium battery positive electrode material consists of the following components in percentage by weight: 80 to 93 percent of positive electrode active material, 5 to 10 percent of lithium iron phosphate, 1 to 5 percent of conductive agent, and 1 to 5 percent of cementing agent. Under the condition of no change of the conventional negative electrode, a small amount of lithium iron phosphate is added into the components of the conventional lithium battery positive electrode material to improve the phenomenon of the invalidation of lithium battery caused by the self discharge of a protection board, so the self discharge of the whole battery pack is improved, the aim of prolonging the storage time of lithium battery is achieved, and the long storage time of the lithium battery can be guaranteed under the condition that a user uses electrical equipment and does not charge the electrical equipment; a manufacturing process of the lithium battery is not required to be changed; the method is simple; and the cost is low.

Description

technical field [0001] The invention relates to the technical field of lithium ion batteries, in particular to a method for prolonging the storage time of lithium batteries and a positive electrode material of lithium batteries. Background technique [0002] At present, most of the positive electrode materials used in lithium-ion batteries are lithium cobaltate, lithium manganate or ternary materials, etc., and its components are mainly active materials plus conductive agents and binders. The active materials are lithium cobaltate, manganese Lithium acid or ternary, etc.; most of the negative electrode materials use graphite as the active material, and then add some conductive agents and binders; the system composed of such positive and negative electrode materials has a common feature that is the late stage of discharge (below 3.3V), especially At the end of discharge (3.0V), the voltage drops very quickly, that is, in this voltage range, the capacity of the lithium-ion bat...

AI Technical Summary

Problems solved by technology

[0003] At present, due to the safety issues of lithium-ion batteries, most lithium battery packs will be assembled with a protective board; however, due to the inherent defects of the protective board itself, there will be a certain amount of leakage current after the lithium battery is installed. The current is around 10uA

Due to the existence of the leakage current, the voltage of the lithium-ion battery is likely to drop continuously due to the leakage current, which will eventually lead to the failure of the lithium-ion battery; especially if the user does not charge it in time after using the electrical appliance, the leakage current will quickly make the lithium battery fail