Strategies for Designing Cryogenic Aqueous Zinc-Ion Batteries: From Electrode Engineering to Electrolyte Optimization

Aqueous zinc-ion batteries (AZIBs) have emerged as a prominent energy storage solution due to their high theoretical capacity, environmental benignity, and cost-effectiveness. However, their practical application at low temperatures is severely hindered by electrolyte freezing, exacerbated dendrite growth, and sluggish ion diffusion kinetics. This review systematically discusses design strategies for freeze-tolerant AZIBs from both electrode and electrolyte perspectives. We first focus on electrode modifications, including ionic doping and defect engineering for manganese- and vanadium-based cathodes, alongside protective strategies for Zn anodes to mitigate dendrite formation at subzero conditions. We then examine electrolyte engineering, focusing on lowering freezing points and suppressing hydrogen bond formation through “water-in-salt” systems, additives, and hydrogel networks. By highlighting recent advances and identifying future research directions, this review provides a multidimensional perspective on developing reliable, cold-resilient AZIBs for diverse real-world employments.