Improvement of storage performance of LiMn2O4/graphite battery with AlF3-coated LiMn2O4

LiMn2O4/graphite batteries using AlF3-coated LiMn2O4 have been fabricated and their electrochemical performance including discharge capacity and cyclic and storage performances have been tested and compared with pristine LiMn2O4/graphite batteries. The LiMn2O4/graphite battery with AlF3-coated LiMn2O4 shows better capacity (108.5 mAhg−1), cyclic performance (capacity retention of 92.7 % after 70 cycles), and capacity recovery ratio (98.6 %) than the pristine LiMn2O4 battery. X-ray diffraction patterns shows that the spinel structure of AlF3-coated LiMn2O4 can be controlled better than that of pristine LiMn2O4 after storage. The improvement in electrochemical performance of the AlF3-coated LiMn2O4/graphite battery is due to the fact that AlF3 acts as a stabilizer and can protect the oxide structure from damaging during storage, leading to a smaller resistance and polarization after storage.