原位聚合法制备锂离子电池负极材料Li4Ti5O12-PAn及其电化学性质

In-situ polymerization method preparation and electrochemical properties of Li4Ti5O12-polyaniline anode material for lithium ion batteries

以醋酸锂和钛酸四丁酯为原料，以乙醇为溶剂，采用溶胶-凝胶法制备Li4Ti5O12；以苯胺、过硫酸铵为原料，以盐酸为溶剂，采用原位聚合法合成Li4Ti5O12-聚苯胺复合材料。采用X射线衍射、红外光谱和电化学测试等对复合材料进行了表征。结果表明，聚苯胺的加入明显提高了Li4Ti5O12的电子导电性能，Li4Ti5O12-PAn复合材料具有比Li4Ti5O12更好的高倍率性能和循环稳定性。0．1C和2．0C放电时Li4Ti5O12-PAn的放电容量分别达到了191．3和148．9mA·h/g，经80次循环后二者平均每次循环容量衰减率分别为0．13％和10.61％。

Li4Ti5O12 powders were prepared by sol-gel method using tetrabutyl titanate, lithium acetate and absolute alcohol as starting materials. Li4Ti5O12-polyaniline （Li4Ti5O12-PAn） composite was prepared by in situ polymerization method using aniline, ammonium persulfate and hydrochloricarried as starting materials. Li4Ti5O12-PAn composite was characterized by XRD, IR combined with electrochemical tests. The results show that the electrical conductivity is enhanced obviously due to the introduction of PAn to Li4Ti5O12. Li4Ti5O12-PAn composite exhibits greater high rate capability and cyclability than Li4Ti5O12. The composite can deliver a specific capacity of 191.3 and 148.9 mA·h/g, only 0.13% and 0.61% of the capacity are lost after discharging for 80 times at 0.1C and 2.0C, respectively.