MXene current collectors for recyclable batteries with improved capacity

Abstract

Due to their high energy density, Li-ion batteries have become the preferred choice for consumer electronics, transportation, and other applications. Current collectors, which are needed for injecting/removing electrons into/from the active material, play a crucial role in the performance of these batteries, influencing capacity, rate capability, and long-term stability, but they receive much less attention. Over the years, there has been a trend of decreasing the thickness of the current collectors to enhance energy density by reducing the weight of the battery. This study focuses on substituting the conventional copper current collector with a thinner and lighter MXene film for high-mass-loading graphite anodes of Li-ion batteries. We also demonstrate the sustainability of our approach to the electrode design by recycling and reusing the MXene current collector after initial use. Our results show improved performances of electrodes using Ti3C2Tx MXene current collectors with reduced total electrode weight and thickness. The electrode-level gravimetric capacity increased by almost 130 mA h g−1, reflecting an 89% increase.