A kind of lithium ion battery negative electrode material and preparation method thereof

Abstract

The invention belongs to the technical field of lithium batteries, and in particular relates to a negative electrode material for a lithium ion battery and a preparation method thereof. The method comprises respectively preparing a Mo5SiB2-ZrB2 composite and a lithium-doped zirconium vanadate material, and then dispersing the two into a Appropriate amount of distilled water, stirred and mixed, and then transferred to a hydrothermal automatic reactor for activation reaction, then transferred to a reaction flask, placed in an ultrasonic disperser, heated to 70-85°C, ultrasonically treated for 2 hours, and the solution was cooled and centrifuged The distilled water is removed, and the solid product is dried to obtain the negative electrode material of the lithium ion battery; in the present invention, by doping lithium into the zirconium vanadate material, the zirconium vanadate material has good thermal shrinkage and cold expansion ability, and can offset lithium The volume change of the negative electrode material of the ion battery during the charging and discharging process or when the temperature increases, thereby improving the stability of the negative electrode material of the lithium ion battery, reducing the internal resistance of the material, and extending the cycle life of the negative electrode material of the lithium ion battery and increasing the rate of discharge. performance.

Description

technical field [0001] The invention belongs to the technical field of lithium batteries, and in particular relates to a lithium ion battery negative electrode material and a preparation method thereof. Background technique [0002] Lithium-ion battery is a new type of chemical power source. Because of its high energy density, high working voltage, long life and no environmental pollution, it is widely used in various portable electronic products, and has been used as an electric vehicle or hybrid power source. Power batteries for automobiles, energy storage devices for aerospace. As a key part of the negative electrode material to promote the development of lithium-ion batteries, it has become a hot spot for researchers. [0003] Graphitic carbon is currently the most commercially successful anode material due to its layered structure suitable for lithium ion insertion / extraction, good electrical conductivity, chemical stability, and low cost. The specific capacity is onl...

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Problems solved by technology

of which NiFe 2 o 4 The theoretical specific capacity is 915mAh / g, which is much higher than that of graphite carbon materials, and has good electrochemical performance (Ding Y, Journal of Power Sources, 2013, 244:610-613), but NiFe 2 o 4 The low conductivity and large volume expansion effect in the charge and discharge process lead to serious capacity fading, large irreversible capacity, and poor cycle performance (Zhao H, Electrochemistry Communication, 2007, 9: 2606-2610; Abrca C V, Journal of Chemical Physics C, 2010 , 114:12828-12832), restricting the development of its practical application

Chinese invention patent (CN103700842A) describes a NiFe 2 o 4 / C Lithium-ion battery negative electrode material and its preparation, the method uses hydrazine as a reducing agent to prepare the negative electrode material precursor in an alkaline environment, and uses non-graphitizable carbon to compound the negative electrode material, and the non-graphitizable carbon can increase the conductivity of the material However, the irreversible capacity of non-graphitized carbon is very high, and there is a phenomenon of voltage hysteresis, which limits the improvement of the electrochemical performance of the material.

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