Flexible lithium ion battery cathode and manufacturing method thereof

Abstract

The invention relates to a flexible lithium ion battery cathode and a manufacturing method thereof. The manufacturing method is characterized in that a lithium ion battery cathode material, a conductive agent and PTFE (Polytetrafluoroethylene) are uniformly mixed with a low-boiling solvent, so as to form slurry, the slurry is dried to obtain a powdered mixture, then the powdered mixture is properly dispersed with a high-boiling solvent, so as to obtain an electrode film containing the high-boiling solvent through pressing, and then the electrode film is fully dried to obtain a flexible electrode. By taking the measures, the polarization degree and impedance of the electrode are effectively reduced, so that the intercalation process of the electrode is more uniform, and the phenomenon of lithium precipitation is effectively prevented.

Description

technical field [0001] The invention relates to the field of lithium-ion batteries, in particular to a flexible lithium-ion battery negative electrode and a manufacturing method thereof. Background technique [0002] Today, as battery raw materials are becoming more and more mature, with the continuous improvement of the market's performance requirements for lithium-ion batteries, users require higher energy density of lithium-ion batteries, especially in the field of rechargeable button-type lithium-ion batteries. According to the above customer requirements, manufacturers continue to improve technology. An effective way to improve the energy density and electrochemical performance of lithium-ion batteries is to reduce the dead space of the battery and increase the filling amount of active materials (positive and negative materials). The manufacturer changed the traditional winding structure of the inner core of the button-type rechargeable lithium-ion battery into a sandwi...

AI Technical Summary

Problems solved by technology

However, the sandwich-structured cell has brought about a sharp increase in the thickness of the negative electrode, which generally reaches more than 0.6mm, which is more than 8 times the thickness of the single-layer coating of the traditional wound electrode. Due to the slow lithium insertion kinetics of the traditional carbon negative electrode material of lithium batteries, it is difficult for For electrodes with a wound structure, the conventional charging rate becomes the high rate of the sandwich structure, and the thickening of the electrode increases the hysteresis of the reaction process. There is a phenomenon that the surface is overcharged and the interior is undercharged. When charging at a conventional rate, there is a danger of serious lithium deposition on the surface. If the lithium deposition is light, it will cause the battery to fail due to short-circuit heating, and if it is severe, there will be a risk of thermal runaway explosion, which greatly limits the sandwich structure. Applications of Li-ion Rechargeable Batteries

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