A rapid formation method of soft-pack power lithium-ion batteries

Abstract

The invention discloses a method for quickly forming a soft power lithium-ion cell. The method comprises the following steps: (S1) supplying a heat source for heating a cell by using a heating plate;(S2) driving a pressurizing plate to pressurize the cell by using a servo motor; (S3) performing gradient charging on the cell; and (S4) charging the cell till reaching high charge state. According tothe invention, a stable, compact and uniform SEI film is formed on a cathode surface, the performance of the lithium-ion cell is greatly promoted, the early failure of the lithium-ion cell in the circulating process is avoided, the yield of the cell is increased, the cell quality is optimized, the forming time of the cell is shortened, the large-scale production of the cell is realized and the method has wide application prospect.

Description

technical field [0001] The invention relates to the technical field of lithium-ion batteries, in particular to a rapid formation method for soft-pack power lithium-ion batteries. Background technique [0002] New energy technology is recognized as a high-tech in the 21st century. As an important part of the new energy field, the battery industry has become a new hot spot in global economic development. At present, lithium-ion batteries are widely used in the fields of electronic communication and transportation because of their advantages such as long life, no memory effect, low self-discharge rate, wide operating temperature range, high voltage platform, and high specific energy. In particular, in recent years, the blowout growth of the automotive power lithium-ion battery market has caused more and more battery manufacturers to expand production and increase capacity. However, the cycleability, consistency, and safety of batteries have always been hotly debated. The topic...

AI Technical Summary

Problems solved by technology

[0004] Chinese Patent No.: CN 104362374 A discloses a method for forming and dividing small-capacity batteries, including the following steps: (1) connecting several small-capacity batteries in parallel, so that the positive tabs of the small-capacity batteries are connected to each other, and the negative tabs are connected to each other : (2) clamp the positive poles of the parallel small-capacity electric cores on the positive pole clips of the formation cabinet, and clamp the negative poles on the negative pole clips of the formation cabinets: (3) the formation cabinets carry out chemical formation treatment on the parallel small-capacity electric cores; the patent The application documents can only complete the formation of small-capacity batteries. For the huge lithium-ion battery market, this method has great limitations and is not conducive to mass production and promotion.

The size of the constant current data used in the patent application document is not representative, and the formed battery cells cannot activate the active material in the battery cells well, and the formed SEI film is not uniform, and then the batteries are assembled into lithium-ion batteries. The poor performance of the battery will cause problems such as premature failure of the lithium-ion battery during the cycle and rapid decay of the volume rate.

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