| The strong development of electric vehicles and portable electronic devicesdemands for high-performance secondary batteries, and some new battery materialsto accommodate the higher performance are required. Nowadays, The lithium-ionbatteries is being considered as a very promising alternative in power battery andenergy storage field with higher output voltage and energy density. Li1+xV1-xO2as anew anode materials candidate for lithium ion batteries, attracts more researchers forits low operating voltage platform and high-volume energy density.Li1+xV1-xO2has the same layered structure as that of LiCoO2.No conversion orreplacement reaction through lithium ion’s intercalation and deintercalation, whichcan improve the battery’s safety. Unfortunately, issues of Li1+xV1-xO2such as highirreversible capacity at the first cycle, poor electrochemical performance in the highrate cycle and the meetable meetable x value, etc need to be solved. In this work,Li1+xV1-xO2anode material is prepared by a solid-state reaction method, and theinfluences of different protective atmosphere, temperature, and x value on theLi1+xV1-xO2physical and electrochemical performance are discussed.The protective gas determines the purity of the final product. Li1+xV1-xO2powders are prepared under argon, hydrogen and with the ratio of95:5. It is foundthat pure Li1+xV1-xO2can be obtained under the mixture of argon and hydrogenatmosphere, while impurities are observed under the other two atmosphere. The bestperformance of Li1+xV1-xO2is obtained at x=0.1and800°C. Its initial dischargecapacity is301mAh·g-1at0.1C, and85mAh·g-1at1C.Various amounts of carbon-coated Li1.1V0.9O2powders are fabricated. The bestperformance is governed by5mass%carbon. Its initial discharge capacity is301mAh·g-1at0.1C, and it decreases to124mAh·g-1after50cycles and106mAh·g-1at1C. This is higher than that of Li1.1V0.9O2powder without carbon-coated by31.8%. |
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