Power generation enhancement of a membrane-free thermally regenerative battery induced by the density difference of electrolytes

Abstract

The development of a low-cost and high-performance thermally regenerative battery is an extremely effective way for waste heat recovery. In this work, a membrane-free thermally regenerative battery (M−TRB) is designed for low-cost and high-performance low-grade thermal energy harvesting. It is exhibited that a M−TRB with a virtual membrane formed by the interface between electrolytes instead of the expensive anion exchange membrane (AEM) can achieve stable power generation successfully. And the maximum power density obtained in M−TRB is 118 W m−2 under the optimal operation condition. Moreover, a combination of M−TRB and hierarchical porous composite electrodes (PCEs) can further improve the maximum power density to 220 W m−2. The much lower cost caused by the simple structure without expensive AEM makes it more competitive in comparison to other TRBs. This indicated that the high-performance and low-cost M−TRB is a potential choice for the construction of systems in future applications.