Quick-charging type lithium ion battery

Abstract

The invention discloses a quick-charging type lithium ion battery. The particle size of a lithium nickel-cobalt-manganese cathode is optimized and screened to obtain cathode particles with the particle size of 2-5 microns, the cathode particles with the particle size of 15-20 microns are mixed, a nano carbon material with the diameter of 10-15 nanometers and the length of 10-20 microns is added, and the nano carbon material forms a good conductive network in the cathode to improve the electron migration speed and the quick charging performance of the cathode; the graphite anode particles are optimally screened to obtain anode particles with the particle size of 10-12 microns, the anode particles with the particle size of 3-5 microns are doped to improve the lithium ion embedding rate of the anode, and the anode particles with the particle size of 23-28 microns are doped to ensure the filling density of the anode material. The particle proportion of the cathode and anode materials is regulated to ensure the quick charging and high-energy density feature of the lithium ion battery.

Description

technical field [0001] The invention relates to a fast charging lithium ion battery. Background technique [0002] Among all forms of energy, electric energy is the easiest to use, the cleanest, the most environmentally friendly, and the most efficient energy. Batteries are the best device for storing electric energy. Among all battery products, lithium batteries are currently the youngest, most advanced, and technologically advanced in the world. Energy products with the highest gold content and the highest energy density, lithium batteries have the advantages of wide working range, stable discharge voltage, low self-discharge rate, long service life, etc., and have been widely used in various fields, especially aerospace, military, long-term Life instrumentation, logistics tracking, cycling automotive electronics, mobile digital products and other fields. [0003] At present, the high-rate lithium-ion battery 18650 type produced in China has a maximum capacity of 2000mAh ...

AI Technical Summary

Problems solved by technology

During this reaction process, if the lithium ion intercalation rate of the negative electrode material does not reach the electron migration rate of the charging current applied by the cell, it will cause the precipitation of lithium metal on the surface of the negative electrode. The precipitation of lithium metal is an irreversible reaction, and the precipitated lithium metal It cannot migrate back to the positive electrode during the discharge reaction, resulting in a decrease in the reversible capacity of the cell

Lower cell active material filling density and larger electrode area can increase the migration and insertion speed of lithium ions, thereby improving the fast charging performance of the battery cell, but the lower cell active material filling density and larger electrode area At the same time, the energy density of the battery will be reduced, and more auxiliary current collectors are required, which further squeezes the filling space of the active material and reduces the energy density of the battery.