Novel Laser Patterned MXene Based Anodes For High Capacity Fast Charging Li-Ion Batteries

Abstract

A flexible anode was developed with 2D material MXenes (Ti3C2Tx) which gained attention recently as energy storage materials. MXenes were synthesized using Lewis acidic etching process from MAX phase powder (Ti3SiC2) and molten salts such as copper chloride (CuCl2), sodium chloride (NaCl) and potassium chloride (KCl). The synthesized MXenes when used as anode material were able to deliver a specific capacity close to 300 mAh/g at 0.1C. Laser patterning was added to the fabrication process to introduce secondary pore networks (SPN's) with pore diameter of $61\ \mu\mathrm{m}$ and edge-to-edge distance of $67\ \mu\mathrm{m}$ into the electrode. Electrochemical performance was evaluated for bar-coated, and laser patterned electrodes inside a CR 2032 half coin-cell with ethylene carbonate and diethyl carbonate (EC: DEC) in 50/50 (v/v) mixed in 1.0M lithium hexafluorophosphate (LiPF6) as electrolyte. Cells with laser patterning showed superior performance at high C-rates such as 2C and 4C with specific capacities of 229 mAh/g and 202 mAh/g.