Lithium ion battery and anode piece

Abstract

The invention belongs to the technical field of lithium ion batteries and particularly relates to an anode piece of a lithium ion battery. The anode piece comprises an anode current collector and an anode diaphragm coated on the anode current collector; the anode diaphragm comprises an anode active substance, a bonding agent and a conductive additive; the anode diaphragm further comprises a positive temperature coefficient material which is (VmR1-m)2)3, wherein R is at least one of Cr, Ba, Al, In, Ga, Sr and Pb, and m is not smaller than 0.5 and not more than 1; and the positive temperature coefficient material accounts for 4.5-30% relative to the total weight of the anode diaphragm. According to the invention, because the anode piece comprises the positive temperature coefficient material, the impedance of the anode diaphragm increases at high temperature to result in the increase of anode polarization, in a charging process, anode potential decreases, corresponding anode oxidation capacity decreases therewith, and thus, the high-temperature cycle performance of the lithium ion battery is increased. In addition, the invention further discloses a lithium ion battery comprising the anode piece.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion batteries, and in particular relates to a lithium-ion battery positive pole piece capable of improving the high-temperature cycle performance of the lithium-ion battery, and a lithium-ion battery including the positive pole piece. Background technique [0002] With the continuous development of modern electronic technology, lithium-ion batteries have become an indispensable chemical power source for electronic products due to their advantages such as high energy density, high voltage platform, low self-discharge rate and long cycle life. [0003] However, electronic products sometimes inevitably need to be used in a specific high-temperature environment. For example, the ambient temperature used by the Global Positioning System (GPS) is even as high as 100°C. A battery pack composed of multiple strings in parallel; and in electric tools, the application of lithium-ion batteries in multiple str...

AI Technical Summary

Problems solved by technology

[0004] Some technical solutions are reported in the existing patent literature to solve the problem of rapid capacity decay of the battery during high-temperature and high-rate cycles. For example, the Chinese patent with application number CN201010181766.6 discloses a high-temperature electrolyte to improve the lithium-ion capacity. The high-temperature cycle performance of the battery. Although this high-temperature electrolyte can improve the high-temperature cycle performance of the lithium-ion battery to a certain extent, the low-temperature performance of the lithium-ion battery becomes worse, thus limiting its further use.