Rapid formation treatment method capable of improving cycle performance of lithium ion battery

Abstract

The invention discloses a rapid formation treatment method capable of improving cycle performance of a lithium ion battery. The rapid formation treatment method comprises the following steps: carryingout secondary constant current charging or tertiary constant current charging on a to-be-formed main body surface of the lithium ion battery under extrusion and high temperature conditions, then directly entering a secondary sealing working procedure, wherein the extrusion condition is 1.0-1.5MPa, and the temperature condition is 45-65 DEG C. The rapid formation treatment method disclosed by theinvention has the advantages that different charging restrictions are adopted according to different lithium ion battery systems, formation time can be shortened to the utmost extent, and a uniform and compact SEI film is formed on an electrode interface, so that the cycle performance of the battery is effectively improved.

Description

Technical field [0001] The invention belongs to the field of lithium ion batteries, and specifically relates to a rapid formation treatment method for improving the cycle performance of lithium ion batteries. Background technique [0002] Since the end of the 19th century, as the human living environment has continued to deteriorate, people have gradually realized the importance of environmental protection, and countries around the world are vigorously developing "new energy" technologies. Lithium-ion batteries are widely used due to their advantages of high energy density, high voltage, low self-discharge, no memory effect, and long cycle life, for example: 3C consumer electronics, electric vehicles, energy storage and other industries. With the continuous depletion of oil and other traditional energy sources and the continuous pollution of automobile exhaust to the environment, pure electric vehicles (EV) and hybrid electric vehicles (HEV), as the future development trend of ne...

AI Technical Summary

Problems solved by technology

During the formation process, if a good SEI cannot be formed, more side reactions will occur in the subsequent cycle of the battery, resulting in a rapid decline in battery capacity and gas generation, which poses a great threat to consumers' lives and property

[0004] The patent name is a chemical formation treatment method for polymer soft-pack batteries (publication number: CN 104269584 A), which discloses a chemical formation treatment method for soft-pack batteries, but in the process of formation, constant current charging The cut-off voltage is 3.9-3.95V, which is not suitable for the lithium iron phosphate system; in addition, this method requires the battery squeezed by the fixture to wait for the temperature to drop to normal temperature after constant current charging. However, the actual situation is that the battery is difficult to dissipate heat in this state, cooling It is very slow to normal temperature and takes a long time to form

At the same time, the traditional chemical conversion treatment takes a long time, and the uniformity and compactness of the SEI film formed on the electrode interface is average, resulting in a short cycle life of the battery. Based on the above reasons, it is urgent to develop a short-time, high-efficiency Chemical conversion treatment of excellent SEI film

Images