Conductive agent used for lithium iron phosphate battery and preparation method thereof

Abstract

The invention discloses a conductive agent used for a lithium iron phosphate battery, and also discloses a preparation method for the conductive agent. The conductive agent consists of a carbon nanotube / carbon black composite material, graphene and a bonding agent in the weight ratio of 1:(0.001-0.1):(0.01-1). The preparation method comprises the following steps of: first, preprocessing the carbon nanotube / carbon black composite material; then, performing ultrasonic dispersion on the carbon nanotube / carbon black composite material and the bonding agent in secondary distilled water; next, adding the graphene into the secondary distilled water under the condition of ultrasonic waves; and finally, performing the ultrasonic dispersion to prepare the conductive agent. The preparation method for the conductive agent is simple; and the prepared conductive agent has uniform dispersion and high stability. The conductive agent has high electronic conductivity and uniform heat conduction; and the lithium iron phosphate battery prepared by adopting the conductive agent has remarkably improved electrochemical performance and obviously reduced alternating-current internal resistance.

Description

technical field

[0001] The invention relates to the technical field of lithium ion secondary batteries, in particular to a conductive agent for lithium iron phosphate batteries and a preparation method thereof. Background technique

[0002] Lithium-ion secondary battery is a new type of high-energy secondary power supply, which has the advantages of large specific capacity, high and stable discharge voltage, good low-temperature performance, environmental friendliness, safety, long life, and weak self-discharge. The above-mentioned advantages of lithium-ion secondary batteries have attracted the favor of scientists from various countries, thus promoting the rapid development of lithium-ion secondary batteries. There are many kinds of positive electrode materials for lithium-ion secondary batteries, mainly including lithium cobalt oxide, lithium manganese oxide, lithium nickel oxide, and lithium iron phosphate. Lithium iron phosphate battery is a lithium ion secondary batte...

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