摘要
采用氢气还原或惰性气体保护煅烧制备磷酸钒锂Li3V2(PO4)3安全隐患大、成本较高。采用碳粉保护煅烧,利用碳更容易被氧化的性质起到还原反应物作用并保护磷酸钒锂不被氧化,同时产生的一氧化碳形成还原气氛排斥空气的扩散侵入。研究表明碳保护煅烧法制备磷酸钒锂是行之有效的;在800℃反应10h制得纯相的磷酸钒锂;在700～750℃左右制得的磷酸钒锂正极材料含有杂相物质,该杂相物质有利于提高材料的电化学性能。
Since the vanadium （V） with a valency of three is very unstable and is easy to be oxidized into V with valency of five, at present, most Li3V2（PO4）3 are prepared with its precursor calcination conducted under the protection of inert or reductive atmosphere. In order to avoid the high production cost caused by the formation of the inert or reductive atmosphere and the danger of happing explosion caused by using H2 as the reductive atmosphere, a new Li3V2（PO4）3 production route with its precursor calcination process protected by carbon was proposed. The precursor immersed in carbon powder before its calcination will be protected by the carbon and the reductive atmosphere of CO during calcination, since the carbon can be oxidized firstly and at the same time can produce the reductive gas CO. The experiments show that the proposed production route of carbon protection is effective. Using carbon protection, after calcination at 800℃ for 10 h, the pure phase Li3V2（PO4）3 Can be obtained, and the Li3V2（PO4）3 with slight impurities will be obtain when the calcination was conducted at 700-750℃. It was found that the above mentioned impurities in Li3V2（PO4）3 can improve the electrochemical performance of the Li3V2（PO4）3 produced.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2009年第4期701-704,共4页
Journal of Chemical Engineering of Chinese Universities
基金
国家科技支撑计划(2007BAQ01055)
国家自然科学基金(50574063)
关键词
磷酸钒锂
正极材料
碳保护
杂相物质
电化学性能
lithium vanadium phosphate
cathode material
carbon protection
impurity
electrochemical performance
