共沉淀法制备镍锰酸锂烧结过程及其性能分析

Analysis on Sintering Process of LiNi_(0.5)Mn_(1.5)O_(4) Prepared by Co-precipitation Method and Its Performance

镍锰酸锂是锂离子电池中具有更好未来的发展方向之一,其具有的高放电平台、低制备成本和低毒性等特点都是社会对锂电池迫切期望具备的特点。采用共沉淀法制备镍锰酸锂,进行了差热-热重和X射线衍射分析,对烧结反应历程及反应动力学进行了研究,得到了煅烧过程物质的变化过程和反应活化能。对制备得到的镍锰酸锂进行了扫描电子显微镜、X射线衍射分析和首次充放电分析。结果表明:在制备镍锰酸锂正极材料时,700℃前碳酸锂基本不参与反应,此时的反应主要为前驱体的分解与氧化;在700℃后碳酸锂开始熔融分解并与前驱体开始进行反应,且反应速率受温度影响大。

LiNi_(0.5)Mn_(1.5)O_(4) is one of the development directions with a better future in lithium-ion batteries,and its characteristics such as high discharge platform,low preparation cost and low toxicity are all features that society urgently expects for lithium batteries to have.In this work,the co-precipitation method was used to prepare LiNi_(0.5)Mn_(1.5)O_(4),and differential thermal-thermogravimetric and X-ray diffraction analyses were performed to study the sintering reaction process and reaction kinetics,and the change process of substances during calcination and the activation energy of the reaction were obtained.Scanning electron microscopy,X-ray diffraction analysis and first charge-discharge analysis were performed on the prepared lithium nickel-manganate.The results showed that in the preparation of lithium nickel-manganate cathode material,lithium carbonate basically did not participate in the reaction before 700℃,and the reaction at this time was mainly the decomposition and oxidation of precursors.After 700℃,lithium carbonate started to melt and decompose and react with the precursor,and the reaction rate was greatly affected by the temperature.