Integrated Dual-Phase Ion Transport Design Within Electrode for Fast-Charging Lithium-Ion Batteries

The development of fast-charging lithium-ion batteries with high energy density is hindered by the sluggish Li+ transport and substantial polarization within graphite electrodes. Herein, this study proposes that the integrated design of liquid electrolyte and solid electrolyte, a dual-phase electrolyte (DP-electrolyte), can facilitate Li+ transport within a thick electrode. A 3D Li3PS4 (LPS) network is constructed within the graphite electrode to form the LPS/graphite electrode. This is achieved through the in situ conversion of the P4S16 into the LPS, a process introduced during the slurry processing. Both experimental findings and simulation outcomes indicate that this design mitigates the concentration polarization due to the improved Li+ transport capability with an overall high Li+ transference number within the electrode. With a high capacity of approximate to 3.1 mAh cm-2 attributed to the graphite electrode, the LiNi0.6Co0.2Mn0.2O2 (NCM622)||LPS/graphite cells demonstrate superior fast-charging capability (4 C, 15 min, charging to approximate to 87.7%) and stable cycling performance (4 C, 700 cycles, approximate to 80% capacity retention). Furthermore, they exhibit commendable low-temperature performance. The Ah-level pouch cell achieves 87.5% recharge in 15 min with an energy density of approximate to 221.5 Wh kg-1. This work offers an alternative avenue for the advancement of fast-charging lithium-ion batteries with practical high energy density. Integrated dual-phase ion transport design within the electrode is proposed to improve the Li+ transport capability with an overall high transference number and reduce the concentration polarization under fast charging conditions, and superior fast-charging capability is realized based on high-areal-capacity anode in Ah-level Li-ion batteries. image