SPST Assistant Professor Liu Wei’s research group recently published an article titled “High-rate and large-capacity lithium metal anode enabled by volume conformal and self-healable composite polymer electrolyte” in Advanced Science.
Lithium-metal batteries can provide a major leap in energy density for the applications of electric vehicles and smart grid, in light of growing demands for large-scale energy storage. However, their widespread implementation has long been fettered due to the safety concern of dendrite-related failure. The researchers demonstrated a solid-liquid hybrid electrolyte consisted of composite polymer electrolyte soaked with liquid electrolyte, to stabilize Li metal anode. The composite polymer electrolyte membrane is composed of self-healing polymer and Li+-conducting nanoparticles. The electrodeposited lithium metal in a uniform, smooth and dense behavior is achieved by use of hybrid electrolyte, rather than dendritic and pulverized structure for the conventional liquid electrolyte-soaked porous separator. The Li foil symmetric cells using hybrid electrolyte can deliver remarkable cycling performance at ultra-high current density up to 20 mA cm−2 with extremely low voltage hysteresis over 1500 cycles. Li metal anode using hybrid electrolyte could also stably run with a large areal capacity of 10 mAh cm-2 at 10 mA cm-2. Furthermore, the Li|Li4Ti5O12 cells based on hybrid electrolyte achieves a higher specific capacity and longer cycling life than that using commercial separator. The superior electrochemical performances of the cells based hybrid electrolyte are mainly attributed to strong adhesion, volume conformity and self-healing functionality of composite polymer electrolyte, providing a novel approach and a significant step toward cost-effective and large-scalable lithium-metal batteries in practical applications.
Postdoc Xia Shuixin is the first author. Assistant Professor Liu Wei is the corresponding author. ShanghaiTech University is the first responsible institution. Thanks to the nice help from Professor Cui Yi and Professor Bao Zhenan from Stanford University. The self-healing polymer was kindly supplied by the Bao group from Stanford University.
Read more at https://onlinelibrary.wiley.com/doi/full/10.1002/advs.201802353.