A Portable Power Concept Based on Combustion and Pyroelectric Energy Conversion

Pyroelectric energy-conversion research is focused on harvesting from waste heat. Meanwhile, there is a need for portable power with extended lifetimes and energy densities. Here, we demonstrate the potential for a portable power concept using pyroelectric energy conversion driven by the heat from on-chip catalytic combustion of methanol. Given the high energy density of liquid fuels (22 MJ/kg for methanol), system conversion efficiencies of only 3% bring the energy density close to Li-ion batteries (∼0.8 MJ/kg). Nanostructured iridium oxide serves as the top electrode and combustion catalyst, with light-off temperatures as low as 105°C. The in-operando energy-conversion performance is measured for thin film La-doped lead zirconate titanate, showing a 2.5× increase in power when operating at the phase transition compared to room temperature. Energy-conversion densities of 48 mJ/cm3 are extracted from the on-chip combustion experiments between temperatures of 230°C and 255°C.