LiNi_(0.5)Mn_(1.5)O_4/Li_4Ti_5O_(12)全电池的制备及电化学性能研究

Preparation and Electrochemical Performance of LiNi_(0.5)Mn_(1.5)O_4/Li_4Ti_5O_(12) Full Cells

以5 V高电压LiNi_(0.5)Mn_(1.5)O_4为正极材料,高安全性Li_4Ti_5O_(12)为负极材料制备了LiNi_(0.5)Mn_(1.5)O_4/Li_4Ti_5O_(12)全电池,重点研究了正负极容量配比对电池电化学性能的影响。其中正极容量过量40%的电池具有最好的倍率和循环性能,在0.5 C电流下,P/N=1.4的电池的最高放电比容量为164.1 m Ah·g^(-1),循环200次的容量保持率为88%;在2 C电流下,P/N=1.4的电池的最高放电比容量为135.2 m Ah·g^(-1),循环740次的容量保持率为91.1%。P/N=1.4的电池良好的倍率和循环性能与其内阻较小、电池极化较小等因素有关。

Full cells of LiNi0.5Mn1.5O4/Li4Ti5O12 have been prepared using LiNi0.5Mn1.5O4 and Li4Ti5O12 （LNMO/LTO） as cathode and anode, respectively. The effects of capacity ratio of positive electrode to negative electrode （P/N） on the electrochemical performance for the full cells have been researched. The system with the P/N for 1.4 has the best cyclic performance and rate capability. At 0.5 C, the full cell of LNMO/LTO with the P/N for 1.4 has the highest discharge specific capacity of 164.1 mAh.g-1, and 88 % is kept at the 200th cycle. At 2 C, the highest specific capacity of 135.2 mAh·g^-1 is delivered and 91.1% is kept for the system. The good rate capability and cyclic performance for the system originate fronl its small resistance and low polarization.