Challenges for Rechargeable Li Batteries

The challenges for further development of Li rechargeable batteries for electric vehicles are reviewed. Most important is safety, which requires development of a nonflammable electrolyte with either a larger window between its lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) or a constituent (or additive) that can develop rapidly a solid/electrolyte-interface (SEI) layer to prevent plating of Li on a carbon anode during a fast charge of the battery. A high Li+-ion conductivity (σLi > 10−4 S/cm) in the electrolyte and across the electrode/electrolyte interface is needed for a power battery. Important also is an increase in the density of the stored energy, which is the…