Porous silicon and carbon mixed anode plate and lithium ion secondary battery comprising same

Abstract

The invention discloses a porous silicon and carbon mixed anode plate and a lithium ion secondary battery comprising the same. The porous silicon and carbon mixed anode plate comprises a porous anode current collector, and two coating layers coating the porous anode current collector, wherein a first layer which is close to the porous anode current collector is made of a mixture of a bonding agent and a conductive agent, a second layer is made of a mixture of a silicon and carbon mixture, the bonding agent and the conductive agent, and the second layer coats the first layer; the lithium ion secondary battery comprises a cathode plate, the porous silicon and carbon mixed anode plate, and an isolating membrane and electrolyte which are arranged between the cathode plate and the porous silicon and carbon mixed anode plate. The porous silicon and carbon mixed anode plate provided by the invention overcomes the defect that the silicon and carbon mixed anode lithium ion secondary battery prepared by adopting a traditional technology is large in volume in the cyclic process, and is capable of increasing the circulation capacity retention ratio of the silicon and carbon mixed anode lithium ion secondary battery, reducing the thickness swelling rate of the lithium ion battery in the cyclic process and increasing the energy density of the lithium ion secondary battery.

Description

technical field [0001] The invention relates to a lithium ion secondary battery, in particular to a lithium ion secondary battery and an electrolytic solution thereof which can improve battery cycle performance. Background technique [0002] Lithium-ion batteries are green, high-energy and environmentally friendly batteries that appeared in the 1990s. Due to their advantages such as high voltage, small size, light weight, high specific energy, no memory effect, no pollution, small self-discharge, and long life, they are widely used in mobile phones. , notebook computers, camcorders, digital cameras and other portable electronic products that emphasize thinness, shortness, and multi-function are rapidly popularized. [0003] At present, most commercialized lithium-ion batteries use lithium cobalt oxide and graphite systems. It is difficult to make breakthroughs in this system. Generally speaking, the total specific capacity of lithium-ion batteries has the specific capacity o...

AI Technical Summary

Problems solved by technology

The volume expansion of the lithium-ion secondary battery is large during the cycle, the cycle performance is reduced, and the volume energy density of the battery is reduced.

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