LiMn<sub>0.6</sub>Fe<sub>0.4</sub>PO<sub>4</sub>/CA Cathode Materials with Carbon Aerogel as Additive Synthesized by Wet Ball-Milling Combined with Spray Drying
Zhenfei Li, Xin Ren, Weichao Tian, Yi Zheng, Liwei An, Jiachen Sun, Ruqian Ding, Lizhi Wen, Li Wang, Guangchuan Liang
Abstract
A LiMn 0.6 Fe 0.4 PO 4 /CA composite with a high tap density and superior electronic conductivity is synthesized by a combination of wet ball-milling, spray drying, and carbothermal reduction with Carbon aerogel (CA) as a carbon additive. CA is a porous nanomaterial with a very large specific surface area. There are 3D network structure between the primary particles of LiMn 0.6 Fe 0.4 PO 4 when CA is used for carbon coating. This 3D network structure not only is beneficial for the improvement of electronic conductivity but also can absorb a large amount of electrolyte, which helps to improve the Li + exchange rate between the electrode and electrolyte. More attention, we found that the primary particles of LiMn 0.6 Fe 0.4 PO 4 coated with CA were more compact than those coated without CA, which greatly improved the tap density of the material. Thus the LiMn 0.6 Fe 0.4 PO 4 /CA composite with appropriate amount of CA exhibits a high tap density of 1.6 g cm −3 and excellent electronic conductivity of 8.5 × 10 −2 S cm −1 simultaneously. Resulting in a high volumetric energy density of 856.1 Wh L −1 at 1 C rate, and discharge capacity of 159.1 mAh g −1 at 0.2 C.