Carbon was used as electronic conductive agent, and metasilicic acid lithium (Li<sub>2</sub>SiO<sub>3</sub>) as ionic conductive agent, the two factors were investigated cooperatively. We evalu...Carbon was used as electronic conductive agent, and metasilicic acid lithium (Li<sub>2</sub>SiO<sub>3</sub>) as ionic conductive agent, the two factors were investigated cooperatively. We evaluated their effect by using spherical spinel LiMn<sub>2</sub>O<sub>4</sub> which prepared ourselves as cathode material. Then Li<sub>2</sub>SiO<sub><sub></sub>3</sub>/carbon surface coating on LiMn<sub><sub></sub>2</sub>O<sub>4</sub> (LMO/C/LSO) which Li<sub><sub></sub>2</sub>SiO<sub><sub></sub>3</sub> inside and carbon/Li<sub><sub></sub>2</sub>SiO<sub><sub></sub>3</sub> coated LiMn<sub><sub></sub>2</sub>O<sub><sub></sub>4</sub> (LMO/LSO/C) were prepared, All of materials were characterized by X-ray diffraction (XRD) and electrochemical test;spherical LiMn<sub></sub>2O<sub></sub>4 was characterized by scanning electron microscopy (SEM);and coated materials were characterized by transmission electron microscopy (TEM). While uncoated spinel LiMn<sub><sub></sub>2</sub>O<sub><sub></sub>4</sub> maintained 72% of capacity in 60 cycles by the rate of 0.2C, and LMO/LSO/C showed the best electrochemical performance, 89% of the initial capacity remained after 75 cycles at 0.2C. Furthermore, the rate performance of LMO/LSO/C also improved obviously, about 30 mAh·g<sup>-1</sup> of capacity attained at the rate of 5C, higher than LMO/C/LSO and bare LiMn<sub><sub></sub>2</sub>O<sub><sub></sub>4</sub>.展开更多
文摘Carbon was used as electronic conductive agent, and metasilicic acid lithium (Li<sub>2</sub>SiO<sub>3</sub>) as ionic conductive agent, the two factors were investigated cooperatively. We evaluated their effect by using spherical spinel LiMn<sub>2</sub>O<sub>4</sub> which prepared ourselves as cathode material. Then Li<sub>2</sub>SiO<sub><sub></sub>3</sub>/carbon surface coating on LiMn<sub><sub></sub>2</sub>O<sub>4</sub> (LMO/C/LSO) which Li<sub><sub></sub>2</sub>SiO<sub><sub></sub>3</sub> inside and carbon/Li<sub><sub></sub>2</sub>SiO<sub><sub></sub>3</sub> coated LiMn<sub><sub></sub>2</sub>O<sub><sub></sub>4</sub> (LMO/LSO/C) were prepared, All of materials were characterized by X-ray diffraction (XRD) and electrochemical test;spherical LiMn<sub></sub>2O<sub></sub>4 was characterized by scanning electron microscopy (SEM);and coated materials were characterized by transmission electron microscopy (TEM). While uncoated spinel LiMn<sub><sub></sub>2</sub>O<sub><sub></sub>4</sub> maintained 72% of capacity in 60 cycles by the rate of 0.2C, and LMO/LSO/C showed the best electrochemical performance, 89% of the initial capacity remained after 75 cycles at 0.2C. Furthermore, the rate performance of LMO/LSO/C also improved obviously, about 30 mAh·g<sup>-1</sup> of capacity attained at the rate of 5C, higher than LMO/C/LSO and bare LiMn<sub><sub></sub>2</sub>O<sub><sub></sub>4</sub>.
