摘要
通过共沉淀法合成LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2材料,用碳包覆对LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2材料进行表面修饰改性,以达到改善高温、高倍率下的循环稳定性。利用碳包覆对LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2进行表面修饰改性后,在室温下,1C的电流密度进行50次循环,材料的容量保持率从80.18%提高到91.14%。同时,在高温(55℃)下,1C的电流密度进行50次循环,材料的容量保持率从82.39%提高至92.05%。这些结果表明,通过在LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2表面进行碳包覆处理,可以提高材料的电子导电率,减少电极材料与电解液的副反应。碳包覆改性使三元正极材料的电化学性能有一定程度的提高。
The LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 material was prepared by co-precipitation method.Surface modification of LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 compound was modified by carbon coating to improve the cycling stability,especially at high temperature and high rate cycling conditions.After the surface modification,the capacity retention increased from 80.18% to 91.14% after 50 cycles at room temperature with current densities of 1 C.Meanwhile,the capacity retention increased from 82.39% to 92.05%after 50 cycles at 55℃ with current densities of 1 C.These results showed that the amorphous carbon layer on the surface of LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 could enhance the electronic conductivity and decrease the side reactions between electrolyte and electrodes.To some extent,the electrochemical properties of carbon-coated ternary cathode materials have been improved.Thus,improving the electrochemical performance.
出处
《中国科技论文》
北大核心
2017年第16期1886-1889,共4页
China Sciencepaper
基金
国家自然科学基金资助项目(51304052)
高等学校博士学科点专项科研基金资助项目(20133514120002)
福建省自然科学基金资助项目(2014J05059)
关键词
电化学
锂离子电池
正极材料
锂镍钴锰氧
共沉淀
表面改性
electrochemistry
lithium-ion batteries
cathode materials
Li[Ni
Mn
Co]O2
co-precipitation
surface modification
