Ni-rich LiNi0·8Co0·1Mn0·1O2 coated with Li-ion conductive Li3PO4 as competitive cathodes for high-energy-density lithium ion batteries

Recently, the Ni-rich LiNi0·8Co0·1Mn0·1O2 (NCM811) cathode with high-energy applications has received tremendous interest for Li-ion batteries (LIBs). But it still suffers from serious capacity degradation upon cycling owing to the involved sur-/interface issues. In the work, we first propose an efficient surface modification strategy to in-situ fabricate the NCM811 coated with solid electrolyte Li3PO4, and systematically investigate the effect of Li3PO4 nano coating layer on electrochemical stability of the NCM811 for LIBs as competitive cathodes. It is the smart surface coating of Li+ conductive Li3PO4 that lowers the sensitivity to H2O and CO2, relieves the evolution of strain-induced intergranular micro-cracks, slows the HF corrosion, and retains the fast Li+ diffusion coefficients with appropriate coating content. The optimized [email protected]3PO4 cathode yields the remarkable electrochemical Li-storage properties in terms of reversible capacities, capacity retention and rate behaviors. More competitively, the [email protected]3PO4 based pouch-type devices deliver a cell-level energy density of ∼304.6 Wh kg−1, along with a capacity retention of 89.6% over 250 cycles at 1.0 C. The appealing features highlight promising application of the resultant [email protected]3PO4 cathodes in next-generation LIBs.