pH-sensitive thermally regenerative cell (pH-TRC) with circulating hydrogen for long discharging time and high-power output

Abstract

Thermally Regenerative Cell (TRC) is a recently proposed promising approach for converting low-grade waste heat into electricity, but the power density and discharging time are limited by the loss of electrode active material and unoptimized cell design. By replacing the early consumable electrode with H2/H+ catalytic electrode and rationally improving the cell design, here we report an advanced pH-sensitive thermally regenerative cell (pH-TRC) with circulating hydrogen to achieve both long discharging time and high-power output. Between the H2/H+ catalytic electrodes we have flowing anolyte and catholyte with different pH values, which can be neutralized through discharging reactions and then thermally regenerated to reset the initial state. With this new design, a favorable peak power density of 5.296 W m−2 is obtained. More importantly, an incredibly long discharging time over 40 h enables the powering of a smart phone in comparison to only hundreds-of-seconds discharging time of previous TRC.