Zinc Ion Thermogalvanic Cell: A New Strategy for Low-Grade Heat Conversion and Energy Storage

Abstract Converting low-grade heat from environment into electricity shows great sustainability for mitigating the energy crisis and adjusting energy configuration. However, the thermally rechargeable devices suffer from poor Seebeck coefficient when a semiconductor or ionic electrolyte is typically employed. Breaking the convention of thermoelectric systems, we propose and demonstrate a new zinc ion thermogalvanic cell to generate electricity from low-grade heat via the thermo-extraction/insertion and thermodiffusion process of insertion-type cathode (VO2-PC) and stripping/plating behavior of Zn anode. Based on this strategy, a high thermopower of ~ 15 mV k− 1 and an excellent output power of 1.2 mW can be impressively obtained. Besides, a high specific capacity and a superior durability are originated from coupling of VO2-PC and Zn. This work with extraordinary energy conversion efficiency and satisfying energy storage capability will pave the way toward construction of thermoelectric setups with attractive property for high value-added utilization of low-grade heat.