High-capacity battery cathode prelithiation to offset initial lithium loss

Loss of lithium in the initial cycles appreciably reduces the energy density of lithium-ion batteries. Anode prelithiation is a common approach to address the problem, although it faces the issues of high chemical reactivity and instability in ambient and battery processing conditions. Here we report a facile cathode prelithiation method that o ers high prelithiation e cacy and good compatibility with existing lithium-ion battery technologies. We fabricate cathode additives consisting of nanoscale mixtures of transition metals and lithium oxide that are obtained by conversion reactions of metal oxide and lithium. These nanocomposites a ord a high theoretical prelithiation capacity (typically up to 800mAhg−1, 2,700mAh cm−3) during charging. We demonstrate that in a full-cell configuration, the LiFePO4 electrode with a 4.8% Co/Li2O additive shows 11% higher overall capacity than that of the pristine LiFePO4 electrode. The use of the cathode additives provides an e ective route to compensate the large initial lithium loss of high-capacity anode materials and improves the electrochemical performance of existing lithium-ion batteries.