Building a battery that can generate electricity from the atmosphere on Mars

Humanity is preparing to land and explore Mars in the next few years. But first, we need to ensure a stable energy source for the base, the rover, and a host of other necessary equipment.

Because the process of transporting many infrastructures to the red planet is extremely difficult, researchers are looking for alternatives. One of them is a battery that exploits the Martian atmosphere as fuel during discharge from the University of Science and Technology of China (USTC) . The research team said: 'This method significantly reduces the weight of the battery, making it more suitable for space missions.'

Mars batteries generate electricity based on a continuous chemical reaction as long as there is fuel. (Illustration photo).

Mars is a harsh planet with a complex atmosphere filled with CO ₂ (95.32%), nitrogen (2.7%), argon (1.6%), oxygen (0.13%) and CO (0.08%). The temperature difference between day and night on the red planet is up to about 60 degrees Celsius.

The USTC team says the battery they invented uses gases in the atmosphere similar to fuel cells used on Earth ( which convert the chemical energy of fuel into electricity). Instead of storing energy like a conventional battery, the Martian battery generates electricity based on a continuous chemical reaction as long as there is fuel.

During discharge, the battery's electrodes interact with gases to produce a chemical reaction that generates electricity. When exhausted, the battery is recharged using solar or nuclear energy to maintain performance.

The battery can withstand significant temperature differences and can operate continuously for several months with a charge/discharge cycle of 1,375 hours (equivalent to about 2 months on Mars). According to tests conducted by the USTC team, at 0 degrees Celsius, the battery still works well with an energy density of 373.9 Wh/kg.

'The charging/discharging process involves the formation and decomposition of lithium carbonate, and small amounts of oxygen and CO act as catalysts to significantly accelerate the conversion of CO ₂ ' , the team explains . They want to increase the amount of interacting gases to improve both battery performance and capacity.

The battery is designed in a foldable form, so it has a large surface area, allowing more gas to be absorbed. The team increased the cell size to 4cm² to increase energy density. The next direction will be to develop solid-state batteries that can withstand low pressure and temperature fluctuations.