Vanadium pentoxide mesoporous cathodes for Li-ion batteries†

The combination of micro- and nanoporosity is advantageous for Li-ion intercalation in battery electrodes. In this work, we synthesize porous 10 μm-sized poly(styrene-vinylpyridine) block copolymer particles via an emulsion-based approach. The vinylpyridine-phase was then subjected to methanol swelling to enable vanadium ions infiltration, followed by calcination to obtain mesoporous vanadium pentoxide particles. These exhibited a hierarchical porosity, and electrodes manufactured from them displayed a very high specific surface area. Two liquid electrolytes were compared to manage solid-electrolyte-interface growth, which can clog nanopores. Notably, the combination of a lithium bis(trifluoromethane)sulfonimide-containing tetraethylene glycol dimethyl ether tetraglyme electrolyte with the hierarchically porous vanadium pentoxide electrodes demonstrated a substantial enhancement in cycling performance, surpassing established industry benchmarks.