(中南大學(xué) 冶金科學(xué)與工程學(xué)院， 長(zhǎng)沙 410083)
摘 要: 采用共沉淀法可以制備出首次放電容量高達(dá)210 mA·h/g的LiNi0.5Mn0.5O2材料（2.8~4.5 V， 電流密度30 mA/g）， 但材料循環(huán)性能受制備過(guò)程中的處理工藝影響很大，處理不嚴(yán)格將導(dǎo)致材料循環(huán)性能嚴(yán)重下降。 圍繞材料的循環(huán)性問(wèn)題， 對(duì)其機(jī)理進(jìn)行了分析并在此基礎(chǔ)上對(duì)制備工藝進(jìn)行了進(jìn)一步改善： 分別從配鋰方式， 燒結(jié)過(guò)程中的升降溫速率以及燒結(jié)的保溫制度進(jìn)行了系統(tǒng)研究。結(jié)果表明： 采用改進(jìn)配鋰方式， 緩慢升溫速率（2 ℃/min）， 高低溫結(jié)合的燒結(jié)制度和快速風(fēng)冷工藝所制備的材料首次放電容量達(dá)到188 mA·h/g， 30個(gè)循環(huán)后仍保持在174 mA·h/g， 循環(huán)效率有了明顯的提高。
關(guān)鍵字: LiNi0.5Mn0.5O2; 鋰離子電池； 正極材料； 循環(huán)性能
cathode material for lithium secondary batteries
ZHAO Hao, HU Guo-rong
（School of Metallurgical Science and Engineering,
Central South University, Changsha 410083, China）
Abstract: LiNi0.5Mn0.5O2 was prepared by co-precipitation methode whose first discharge capicity can achieved 210 mA·h/g(2.8-4.5 V, current density: 30 mA/g). But the material's cycle performance is seriously affected by the synthesis conditions.If the synthesis conditions were not seriously controlled the material's cycle performance would be bad. The inner cause to the cycle performance was studied and the preparation way was reformed. By improving the matched way of lithium, studing the affection of heating and cooling rates on the material and renewing the heat treatment, the material's cycle performance was improved. The material's first discharge capicity can achieve 180 mA·h/g and aft, er 30 cycles the discharge capicity remains 175 mA·h/g.
Key words: LiNi0.5Mn0.5O2; lithium-ion battery; cathode material; cycle performance
