Engineering Artificial SEI for Improving Performance of Anode Free Batteries

Abstract

Practical implementation of a lithium battery or an anode-free battery with promising high capacity is hampered by dendrite formation and low coulombic efficiency [1,2]. Most notably, these challenges stem from non-uniform lithium platting and unstable SEI layer formation. Here, we revealed a homogeneous lithium deposition and effective dendrite suppression with engineering artificial SEI layer. Surface coating reinforces a thin and robust artificial SEI layer film formation via hosting lithium and regulating the inevitable reaction of lithium with electrolyte. The cell with engineered SEI layer showed stable cycling of lithium with an average coulombic efficiency of ~100% over 200 cycles and low voltage hysteresis (~30 mV) at current density of 0.5 mA cm-2. Moreover, we have proved the anode-free battery experimentally by integrating it with various cathodes into a full cell configuration. The new cell demonstrated stable cycling with excellent average coulombic efficiency. These impressive enhanced cycle life and capacity retention results from the synergy of electrode modification, high electrode-electrolyte interface compatibility, and stable artificial SEI formation. Our result opens up a new route to realize the anode-free batteries by engineering artificial SEI layer to achieve safe interfacial chemistry and controlled dendrite formation. Reference s : [1] A.M. Tripathi, W.N. Su and B.J. Hwang, Chem. Soc. Rev., 47, 736–851 (2018). [2] J.H. Cheng, A.A. Assegie, C.J. Huang, M.H. Lin, A.M. Tripathi, C.C. Wang, M.T. Tang, Y.F. Song, W.N. Su, and B.J. Hwang, J. Phys. Chem. C, 121, 7761–7766 (2017).