Manufacturing process of cylindrical lithium ion battery

Abstract

The invention provides a manufacturing process of a cylindrical lithium ion battery, which belongs to the field of lithium ion batteries and comprises the following steps: S1, simultaneously manufacturing a positive plate and a negative plate, and preparing for winding; s2, winding: winding the positive plate and the negative plate which are manufactured in the step S1 and a diaphragm, arranging the diaphragm between the positive plate and the negative plate, and forming a roll core after winding; s3, baking to reduce the moisture value of the surface of the roll core; s4, electrolyte infiltration: immersing the roll core wound in the S2 into the electrolyte in a liquid injection chamber, changing the environment in the liquid injection chamber into a vacuum state, and taking out the roll core after liquid injection is completed; S5, assembling in a shell, clamping a battery shell, and carrying out roll core in-shell treatment on the roll core subjected to infiltration and liquid injection; and S6, pre-charging, aging, forming and grading capacity. According to the present invention, the coating process and the rolling process are combined together, the production process is substantially simplified, and the immersion type electrolyte injection process is adopted so as to effectively improve the infiltration degree of the electrolyte and improve the battery performance.

Description

technical field [0001] The invention belongs to the field of lithium ion batteries, and relates to lithium ion batteries for new energy vehicles, in particular to a manufacturing process for cylindrical lithium ion batteries. Background technique [0002] A cylindrical lithium-ion battery is a battery structure in which the positive electrode, negative electrode, and separator are wound to form a cylindrical core structure and sealed by a cylindrical metal casing. Compared with square hard-shell and soft-pack batteries, cylindrical batteries have relatively mature manufacturing processes, can effectively suppress the expansion of pole pieces, and are easy to control the spread of thermal runaway. In recent years, with the increasing requirements of new energy vehicles on battery energy density, power performance and safety, the structure of cylindrical batteries has undergone significant changes, and the volume and size of batteries have become higher and higher. Traditional...

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Problems solved by technology

[0004] In addition, in the traditional liquid injection process, the cylindrical lithium-ion battery needs to be pressurized or vacuumed several times after liquid injection, but the time of this pressurization or vacuuming is not easy to grasp and control, and with the winding core As the size increases, it is difficult for the electrolyte to infiltrate into the inside of each pole piece of the winding core, resulting in poor wetting

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