ABSTRACT Proton batteries are emerging as a promising next‐generation energy storage technology, featuring high safety, superior power density, and excellent stability. However, the development of solid‐state electrolytes with high proton conductivity remains a significant challenge. Herein, graphdiyne oxide (GDYO) is proposed as a novel solid‐state electrolyte for proton batteries for the first time. By constructing a three‐dimensional hydrogen bonding network with phosphoric acid, the resultin