3D printing nanocomposite gel-based thick electrode enabling both high areal capacity and rate performance for lithium-ion battery

Abstract

The development of robust performing lithium-ion batteries (LIBs) with high areal capacity is a challenge that persists to date. One commonly used strategy to increase areal capacity is increasing the thickness of the battery electrodes. However, the practical application of these thick electrodes is hindered thanks to the fundamental issues of incomplete electrolyte infiltration, poor mechanical properties, and slow charge and ion transport. Herein, a new method is presented wherein a thick electrode is constructed by 3D printing a highly-conductive and hierarchical network of silver nanowires (AgNWs), graphene and Li4Ti5O12 together as a mixed functional ink. The amalgamation of highly conductive AgNW network, interconnected 3D graphene scaffold, and hierarchical porous structure can allow the 3D-printed electrode to demonstrate much improved charge and ion transport, and to alleviate internal stresses during the charging and discharging process even under ultrahigh thickness state. As a result, the LIBs utilizing these thick electrodes have a rate capability of 121 mAh g−1 at 10C, high areal capacities up to 4.74 mAh cm−2, and stable cycling performance (capacity retention of ~95.5% after 100 cycles). These performance metrics provide a route for a new design strategy using thick electrodes for high-performance energy storage devices.