Effect of Charging Protocol on the Performance of LiNi_0.6Co_0.2Mn_0.2O₂ Lithium Slurry Batteries

With flowable slurry electrode architecture, lithium slurry battery (LSB) has the advantages of high energy density and independent energy and power, which can be used as an excellent energy storage device. However, its practical application is still hindered by multiple factors, including prolonged ion/electron passage, serious interfacial parasitic reactions, low energy efficiency, et al. The special electrode structure can influence the charge percolation pathway, reduce the apparent Li+ diffusion coefficient (DLi+), and further impact the battery performances. Herein, a special six-stage constant current (SS-CC) charging protocol for LSB is developed based on DLi+ under different state of charges, that is, higher charging rate at larger DLi+. Comparing with other charging protocols commonly used in lithium-ion batteries such as constant current-constant voltage, the LSB charged by SS-CC protocol not only shows higher energy efficiency, but also enhanced cycle stability. This is attributed to the better synergy between lithium desertion and plating, which kinetically reduces the parasitic reactions such as solid-electrolyte interphase accumulation, dead lithium, or dendrite generation. It is believed that this charging protocol design strategy can also be applied in other LSB systems.