The utilization of in-situ resources such as food waste or plants grown on Mars combined with the available Martian regolith and atmosphere presents a path towards battery separators with increased sustainability, energy density, and durability. Separators that focus on CO₂ reduction take advantage of both a highly relevant source of materials on Mars and a solution to an increasingly relevant problem of the increase of atmospheric CO₂ on Earth.

In this paper we evaluate the electrochemical and thermal properties of gel electrolytes synthesized from food waste and their performance in CO₂ reduction. Our work focuses on the extraction of pectins from soybean hull and tomato pomace as sources of inedible biomass. Cross-linking and ionic activity of the pectin-based gel electrolytes are determined by the integration of monovalent and divalent cations. A biomass-based polymer electrolyte provides a novel method of using in-situ resources for chemical conversion and energy storage that is critical for long-term space travel.