Enhancement in electrochemical properties of boron-doped LiNi0.815Co0.15Al0.035O2 cathode

The lattice of the cathode material LiNi0.815Co0.15Al0.035O2 cathode (NCA) was doped with B3+ using a high-temperature solid-phase method, considerably improving the electrochemical properties of the NCA. Results of X-ray diffraction analysis and Rietveld refinement show that B3+ can enhance lattice ordering by minimising Li+/Ni2+ mixing. The scaning electron microscopy observations indicated that the B3+ doped changes the particle morphology. The specific discharge capacities of 1.5%B-NCA were 178.31 and 123.74 mAhg−1 at 0.2 and 5C, respectively. After 100 cycles, the specific discharge capacity was 176.29 mAhg−1 at 0.2C with a capacity retention of 98.87%. Boron doping significantly improves the structural stability of nickel-rich cathode materials by suppressing the detrimental H2→H3 phase transition, thus improving the electrochemical performance of nickel-rich ternary lithium-ion batteries.