UC San Diego

Driven by the flourishing of renewable energy sources and increasing demands of portable electronics and electric vehicles, high-performance energy storage devices are required for the applications at different scales. Benefiting from the small size, high surface area and hierarchical structures, nanostructured materials have been playing critical roles for the development of advanced energy storage devices.

This dissertation will discuss the applications of nanostructured materials to resolve the unique problems for different types of energy storage devices. Chapter 2 provides a new strategy to fabricate a cation exchange membrane features a dense, crack-free tungsten oxide coating layer on Nafion that also penetrates into the Nafion’s hydrophilic, ionic cluster regions. The hierarchical structural designs overcome the inherent tradeoff between conductivity and permeability of ion exchange membranes for redox flow batteries. In Chapter 3, a facile and scalable method is demonstrated to fabricate a 3D lithium metal anode with lithium nitrate, polyvinylidene difluoride, and nano-sized carbon black. The multi-functional 3D electrodes enable dendrite-free lithium metal cycling with high coulombic efficiency. In Chapter 4, a non-toxic, free-standing and flexible cathode is developed by grafting polydopamine on carbon nanotubes for aqueous zinc-ion battery. Cross-linked highly uniform active materials and the efficient conducting network overcome the long term cycling stability issue of aqueous zinc-ion batteries.