Ultrathin positively charged electrode skin for durable anion-intercalation battery chemistries
Davood Sabaghi, Zhiyong Wang, Preeti Bhauriyal, Qiongqiong Lu, Ahiud Morag, Daria Mikhailovia, Payam Hashemi, Dongqi Li, Christof Neumann, Zhongquan Liao, Anna Maria Dominic, Ali Shaygan Nia, Renhao Dong⧫, Ehrenfried Zschech, Andrey Turchanin, Thomas Heine, Minghao Yu, Xinliang Feng
Abstract
Abstract The anion-intercalation chemistries of graphite have the potential to construct batteries with promising energy and power breakthroughs. Here, we report the use of an ultrathin, positively charged two-dimensional poly(pyridinium salt) membrane (C2DP) as the graphite electrode skin to overcome the critical durability problem. Large-area C2DP enables the conformal coating on the graphite electrode, remarkably alleviating the electrolyte. Meanwhile, the dense face-on oriented single crystals with ultrathin thickness and cationic backbones allow C2DP with high anion-transport capability and selectivity. Such desirable anion-transport properties of C2DP prevent the cation/solvent co-intercalation into the graphite electrode and suppress the consequent structure collapse. An impressive PF 6 − -intercalation durability is demonstrated for the C2DP-covered graphite electrode, with capacity retention of 92.8% after 1000 cycles at 1 C and Coulombic efficiencies of > 99%. The feasibility of constructing artificial ion-regulating electrode skins with precisely customized two-dimensional polymers offers viable means to promote problematic battery chemistries.