Anode-Less All-Solid-State Batteries Operating at Room Temperature and Low Pressure

Abstract

Anode-less all-solid-state batteries (ASSBs) are being targeted for next-generation electric mobility owing to their superior energy density and safety as well as the affordability of their materials. However, because of the anode-less configuration, it is nontrivial to simultaneously operate the cell at room temperature and low pressure as a result of the sluggish reaction kinetics of lithium (de)plating and the formation of interfacial voids. This study overcomes these intrinsic challenges of anode-less ASSBs by introducing a dual thin film consisting of a magnesium upper layer with a Ti3C2Tx MXene buffer layer underneath. The Mg layer enables reversible Li plating and stripping at room temperature by reacting with Li via a (de)alloying reaction with a low reaction barrier. The MXene buffer layer maintains the electrolyte-electrode interface by inhibiting the formation of voids even at low pressure of 2 MPa owing to the high ductility of MXene. This study highlights the importance of a combined chemical and mechanical approach when designing anode-less electrodes for practical adaptation for anode-less ASSBs.