NASA believes that its solid-state battery under development is exceeding its goals. Its innovative battery pack is lighter, safer, and performs better than current batteries do, it says. This development holds promise for evolving electric aircraft. However, the national aeronautics and space administration program dates back to early human space flights, when NASA battery power was super critical.
Battery Power for NASA Project Mercury
The national aeronautics and space administration’s human flight space program began with Project Mercury in 1959. The plan was to put a person in space, and return them safely back to earth. NASA battery power was supercritical in those days, because they used primary, non-rechargeable silver-zinc batteries.

Silver-zinc (Ag-Zn) battery cells were the best technology available to the Mercury team. In fact, they had the highest density ever, until John Goodenough’s lithium-ion batteries arrived. Russia used Ag-Zn batteries for its Sputnik satellites, as did United States for its saturn launch vehicle, apollo lunar module, lunar rover, and life-support backpack, according to Wikipedia.
How Much Battery Energy Did NASA Need?
NASA’s Mercury capsule used three, 3-kilowatt-hour primary silver-zinc batteries for its main energy source. Plus it had another two on standby, together with a 1.5-kilowatt-hour squib battery to fire a detonator. These NASA battery power sources required careful calculation, in order to optimize weight and size.
Calculating spacecraft battery power takes several factors into account, according to website City Life. Accuracy would have been supercritical in the case of the Gemini spacecraft, where every cubic inch counted. There were no solar panel backups, because the silver-zinc batteries were single use, and could not recharge.
The following factors affected power requirements that NASA engineers must have agonized over:
- Satellite size increased the number of systems and instruments requiring power.
- Payload and instrumentation had to be as simple as possible to limit energy requirements.
- Mission duration added a time dimension, linearly increasing power requirements.
If the Gemini module had run out of power, which it thankfully did not, then it would have simply ceased to function. There was no satellite-recovery equipment in the 1960’s. We salute the bravery of those early astronauts, willing to give everything they had to advance the frontiers of space exploration.
More Information
Nuclear Batteries for Space Exploration
Sulfur Selenium Battery Breakthrough at NASA
Preview Image: Evolution of NASA Spacecraft
Project Mercury – A Wikipedia Evaluation