High-Voltage Lithium-Ion Battery Using Substituted LiCoPO: Electrochemical and Safety Performance of 1.2 Ah Pouch Cell.

A LiCoPO-based high-voltage lithium-ion battery was fabricated in the format of a 1.2 Ah pouch cell that exhibited a highly stable cycle life at a cut-off voltage of 4.9 V.

Novel polymer coating for chemically absorbing CO for safe Li-ion battery.

Gas evolution in Li-ion batteries remains a barrier for the implementation of high voltage materials in a pouch cell format; the inflation of the pouch cell is a safety issue that can cause battery failure. In particular, for manganese-based materials employed for fabricating cathodes, the dissolution of Mn in the electrolyte can accelerate cell degradation, and subsequently gas evolution, of which carbon dioxide (CO) is a major component. We report on the utilization of a mixture of polymers that can chemically absorb the CO, including the coating of aluminum foils, which serve as trapping sheets, introduced into two Ah pouch cells-based on a LiMnFePO (cathode) and a LiTiO (anode).

Increasing the Affinity Between Carbon-Coated LiFePO4/C Electrodes and Conventional Organic Electrolyte by Spontaneous Grafting of a Benzene-Trifluoromethylsulfonimide Moiety.

The grafting of benzene-trifluoromethylsulfonimide groups on LiFePO4/C was achieved by spontaneous reduction of in situ generated diazonium ions of the corresponding 4-amino-benzene-trifluoromethylsulfonimide. The diazotization of 4-amino-benzene-trifluoromethylsulfonimide was a slow process that required a high concentration of precursors to promote the spontaneous grafting reaction. Contact angle measurements showed a hydrophilic surface was produced after the reaction that is consistent with grafting of benzene-trifluoromethylsulfonimide groups.