(1. 湖南立方新能源科技有限公司，株州 412007；
2. 深圳振華新材料有限公司，深圳 518102；
3. 東莞新能源有限公司，東莞 523080)
摘 要: 采用前驅(qū)體混合燒結(jié)法制備60%LiCoO2-40%LiNi0.5Mn0.3Co0.2O2(摩爾分?jǐn)?shù))復(fù)合材料，采用X射線衍射(XRD)和場發(fā)射掃描電鏡(FESEM)對試樣的顯微組織和形貌進(jìn)行表征，采用差熱分析(TG-DSC)和過充試驗(yàn)測試該材料的安全性能。結(jié)果表明：與物理混合材料相比，復(fù)合材料具有很好的層狀結(jié)構(gòu)。混合燒結(jié)法通過前驅(qū)體的燒結(jié)使兩種材料晶粒產(chǎn)生了融合，而產(chǎn)生晶粒融合的材料既保持了LiCoO2的高體積能量密度(容量為156 mA？h/g、壓實(shí)密度為4.0 g/cm3)，還改善了材料的導(dǎo)電能力和安全性能。使用該材料制成的1.6 A？h聚合物全電池，不但可以通過1C/12 V過充測試，而且具有優(yōu)良的循環(huán)性能。該復(fù)合材料在常溫和45 ℃下循環(huán)500次，容量保持率仍在85%以上。
關(guān)鍵字: 鋰離子電池；正極材料；LiCoO2；混合燒結(jié)；電化學(xué)性能；過充
（1. Li-Fun Technology Co. Ltd, Zhuzhou 412007, China;
2. Shenzhen Zhenghua E-Chemical Co. Ltd, Shenzhen 518102, China;
3. Amperex Technology Co. Ltd, Dongguan 523080, China）
Abstract:60%LiCoO2-40%LiNi0.5Mn0.3Co0.2O2 (mole fraction) compound material was synthesized by precursor mixed sintering method. The microstructure and morphology of the compound material were characterized by X-ray diffraction (XRD) and field emitted scanning electronic microscopy (FESEM). The safety performance was analyzed by TG-DSC and abuse test. The results show that, compared with physical mixing material, the compound material has a better bonded crystalline and mixing effect, resulting in improved conductivity and structural stability. The material has high capacity (156 mA？h/g), high pressing density (4.0 g/cm3) and improved safety. 1.6 A？h polymer cells with compound material not only show excellent cycle life at room temperature and elevated temperature, the capacity retention is more than 85% after 500 cycle, but also exhibit good overcharge performance.
Key words: lithium ion battery; cathode material; LiCoO2; mixed sintering; electrochemical properties; overcharge
