低温熔盐法合成球形LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2研究

采用低温熔盐法合成了锂离子电池正极材料Li Ni1/3Co1/3Mn1/3O2,并就低温熔盐0.62xLi NO3-0.38xLi OH-(1-x)CH3COOLi.2 H2O的具体比例、焙烧温度和焙烧时间对材料的影响进行了对比研究.XRD结果表明以x=0.6的低温共熔盐,经3阶段温度烧结(200℃,3 h;600℃,制备的样品的α-NaFeO2层状结构发育的较为完备.SEM扫描显示材料是由许多片状晶体构成的球形颗粒.材料在2.8～4.3 V范围内充放电,倍率为0.2 C时,首次放电比容量为173.6 mA.h.g-1,循环20次后容量保留97.4%;倍率为1 C时,首放126.0 mA.h.g-1,循环20次后容量保留94.1%.

Synthesis Conditions of Cathode Material LiNi1/3Co1/3Mn1/3O2 Prepared by Molten Salt Method

Cathode material for LiNi1/3Co1/3Mn1/3O2 lithium-ion batteries has been prepared by molten salt method.The effects from the rate of the eutectic mixed molten salt,sintering time and sintering temperature during preparation have been studied.XRD results show that the product,prepared using the x=0.6 of the eutectic mixed molten salt and Calcinating as follows 200 ℃ for 3 h,600 ℃ for 6 h,900 ℃ for 10h,has good α-NaFeO2 layer structure.SEM shows that the powders are composed of well-dispersed spherical particles and each of the spherical particles is composed of a large number of sheet crystalline grains.Electrochemical studies indicate the first discharge of this sample is 173.6 mA·h·g-1 at a specific current of 0.2C between 2.8-4.3V and 97.4% retention after 20 cycles;126.0 mA·h·g-1 at1C and 94.1% retention after 20 cycles.