Synthesis and characterization of LiFePO4 coating with aluminum doped zinc oxide
(1. Department of Materials Science, Fudan University, Shanghai 200433, China;
2. Felie Li-ion Battery Manufacture Co., Ltd., Wuxi 214028, China)
2. Felie Li-ion Battery Manufacture Co., Ltd., Wuxi 214028, China)
Abstract: Aluminum doped zinc oxide (AZO), as an electrically conductive material, was applied to coating on the surface of olivine-type LiFePO4 synthesized by solid-state method. The charge-discharge test results show that the rate performance and low-temperature performance of LiFePO4 are greatly improved by the surface treatment. Even at 20C rate, the discharge specific capacity of 100.9 mA·h/g was obtained by the AZO-coated LiFePO4 at room temperature. At -20 °C, the discharge specific capacity at 0.2C for un-coated LiFePO4 and the coated one are 50.3 mA·h/g and 119.4 mA·h/g, respectively. It should be attributed to the electrically conductive AZO-coating which increases the electronic conductivity of LiFePO4. Furthermore, the surface-coating increases the tap-density of LiFePO4. The results indicate that the AZO-coated LiFePO4 is a good candidate of cathode material for applying in lithium power batteries.
Key words: lithium ion battery; LiFePO4; coating; cathode material; aluminum doped zinc oxide