Beneficial impact of lithium bis(oxalato)borate as electrolyte additive for high‐voltage nickel‐rich lithium‐battery cathodes

High-voltage nickel-rich layered cathodes possess the requisite, such as excellent discharge capacity and high energy density, to realize lithium batteries with higher density. However, materials suffer from structural interfacial instability at voltages (>4.3 V). To reinforce stability of these cathode elevated voltages, borate salts are investigated electrolyte additives generate a superior cathode-electrolyte interphase. Specifically, use bis(oxalato)borate (LiBOB) leads an enhanced cycling retention 81.7%. Importantly, almost no voltage hysteresis is detected after 200 cycles 1C. This outstanding electrochemical performance attributed stability, which attained by suppressing generation micro-cracks superficial degradation upon cycling. The improved stems formation fortified borate-containing interphase protects highly reactive parasitic reactions electrolyte. Finally, decomposition process LiBOB possible adsorption routes surface deduced elucidated.