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.