On Mars studies have shown that carbon dioxide solidifies to dry ice at the poles. During the winter months can electrolysis be applied to collected and then contained liquid $CO_2$ to replenish oxygen reserves by creating an engine that uses $CO_2$ as the oxidizer?
Could solar powered electrolysis of liquid $CO_2$ and $H_2O$ during the summer provide liquid $O_2$ and Hydrogen to power a generator in place of using batteries for electrical storage for generator during winter?
What can be added to liquid CO2 to allow better electrolysis to crack $CO_2$ or to used as an oxidizer for $CO_2$ combustion engine?
The main component of the atmosphere of Mars is carbon dioxide (CO2) at 95.9%. Each pole is in continual darkness during its hemisphere's winter, and the surface gets so cold that as much as 25% of the atmospheric CO2 condenses at the polar caps into solid CO2 ice (dry ice). When the pole is again exposed to sunlight during summer, the CO2 ice sublimes back into the atmosphere. This process leads to a significant annual variation in the atmospheric pressure and atmospheric composition around the Martian poles.
$CO_2$ sublimes but it can be self collected in vast containers or an underground cave that can be capped open during winter, closed and kept as a super liquid during summer to power generators similar to steam engines?