纳米尖晶石Li_xMn_2O_4的制备与电化学性能表征

Preparation of Nano-spinel Li_xMn_2O_4 and Characterization of its Electro chemical Properties

Nano-spinel Li x Mn 2 O 4 (0.6≤x≤1.0)was synthesized by two steps of copre cipitation and calcination.The influences of calcination temperature,time and Li /Mn ratio on the crystal structure and the particle size of Li x Mn 2 O 4 were investigated.It was shown that the higher the calcination temperature,the more complete the crystal structure,and the larger the partic le size.Moreover,the influence of c alcination time on the crystal structure was insignificant when it was more than 3h at 700℃.With the increase of x in Li x Mn 2 O 4 in the range of 0.6～1.0,the d 111 and lattice parameter a increased fi rst and then decreased.The electrochemical properties of nano-spinel LiMn 2 O 4 using as cathode material of lithium-ion battery were studied.The low di scharge capacity might be due to the irreversible capacity loss brou ght by the large surface area and latt ice vacancies of the nano-spinel.

Nano-spinel LixMn2O4(0.6 less than or equal to x less than or equal to 1.0) was synthesized by two steps of coprecipitation and calcination. The influences of calcination temperature, time and Li/Mn ratio on the crystal structure and the particle size of LixMn2O4 were investigated. It was shown that the higher the calcination temperature, the more complete the crystal structure, and the larger the particle size. Moreover, the influence of calcination time on the crystal structure was insignificant when it was more than 3h at 700degreesC. With the increase of x in LixMn2O4 in the range of 0.6 similar to 1.0, the d(III) and lattice parameter a increased first and then decreased. The electrochemical properties of nano-spinel LiMn2O4 using as cathode material of lithium-ion battery were studied. The low discharge capacity might be clue to the irreversible capacity loss brought by the large surface area and lattice vacancies of the nano-spinel.