Effects of Ti additive on the structure and electrochemical performance of LiMnPO4 cathode material

• The (1-x)LiMnPO4·LixTix(PO4)δ samples were synthesized through a solid-state method.
• The content of Ti additive greatly affects the electrochemical performance of LiMnPO4.
• The sample synthesized with 10% Ti exhibits the best electrochemical performance.

The (1-x)LiMnPO4·LixTix(PO4)δ (x = 0, 0.01, 0.05, 0.10, 0.15, 0.20) cathode materials are successfully synthesized through a solid-state method. The structures and electrochemical properties of the prepared samples have been characterized comprehensively. It is found minority phases containing LiTi2(PO4)3 and TiP2O7 were formed. The addition of Ti has obviously reduced the size of grains. Electrochemical tests indicate that the discharge capacities of LiMnPO4 samples can be significantly improved with the addition of Ti. Especially, the (1-x)LiMnPO4·LixTix(PO4)δ sample with x = 0.1 has the largest discharge specific capacity, which is more than 131 mAh g−1 at 0.05 C. And EIS tests1demonstrate that the 0.9LiMnPO4·Li0.1Ti0.1(PO4)δ sample has lower charge transfer resistance and higher diffusion coefficient than the pristine LiMnPO4 sample.