(1. 中南大學(xué) 化學(xué)化工學(xué)院，長(zhǎng)沙 410083；
2. 肇慶學(xué)院 化學(xué)化工學(xué)院，肇慶 526061；
3. 中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 以FePO4、Li2CO3和葡萄糖為原料，用液氮急速淬火法制備單一橄欖石結(jié)構(gòu)的鋰離子電池正極材料LiFePO4/C。結(jié)果表明：淬火使得LiFePO4晶格中產(chǎn)生Li空位，有利于提高其電子導(dǎo)電性。淬火樣品的一次顆粒細(xì)小(100~500 nm)，無明顯團(tuán)聚，并形成多孔結(jié)構(gòu)；該樣品在1C、2C和4C倍率下的首次放電比容量分別為151.4、138.0和116.7 mA·h/g，循環(huán)100次后的容量保持率高達(dá)99.3%、98.6%和94.5%。
關(guān)鍵字: 鋰離子電池；正極材料；磷酸鐵鋰；液氮；淬火
（1. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
2. College of Chemistry and Chemical Engineering, Zhaoqing University, Zhaoqing 526061, China;
3. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:A single olivine-type LiFePO4 was synthesized by liquid nitrogen rapid quenching method, using FePO4, Li2CO3 and glucose as raw materials. XRD refinement results indicate that rapid quenching leads to the formation of a number of Li vacancies in LiFePO4 crystals. These defects are beneficial to improving the electronic conductivity of LiFePO4. The quenched sample shows the primary particles size of 100−500 nm. The p, articles exhibit little agglomeration, and form a porous structure. The sample exhibits an initial discharge capacity of 151.4, 138.0 and 116.7 mA·h/g at 1C, 2C and 4C rate, and shows the capacity retention of 99.3%, 98.6% and 94.5% after 100 cycles, respectively.
Key words: lithium-ion batteries; cathode materials; lithium iron phosphate; liquid nitrogen; quenching
