The idea is simple: the favorability of a chemical reaction is a function of temperature, some reactions are more favorable at high temperatures, some at lower. For electrochemical reactions (e.g. batteries) this means a change in voltage at different temperatures. Some reactions have higher voltages, some lower. By choosing a pair of redox reactions such that the direction of charge transfer can be reversed within a specified temperature envelope, one can create a thermal engine that directly converts heat to electrical energy without requiring a turbine.
There’s lots of research on this, sometimes called the ‘omnivorous’ flow battery.
Thermo-electrochemical cycles.
The idea is simple: the favorability of a chemical reaction is a function of temperature, some reactions are more favorable at high temperatures, some at lower. For electrochemical reactions (e.g. batteries) this means a change in voltage at different temperatures. Some reactions have higher voltages, some lower. By choosing a pair of redox reactions such that the direction of charge transfer can be reversed within a specified temperature envelope, one can create a thermal engine that directly converts heat to electrical energy without requiring a turbine.
There’s lots of research on this, sometimes called the ‘omnivorous’ flow battery.