If you’ve ever had your car start sluggishly, or not at all, on a particularly frigid winter morning, you know standard batteries do not like extreme cold. That’s why NASA researchers are working to develop a battery that could function in the brutal cold of the Moon’s South Pole, where nighttime temperatures plunge to minus 328 degrees Fahrenheit (minus 200 Celsius). 

For future lunar operations, a battery will need to work immediately when warmed up and be able to power everything from an astronaut’s emergency kit to a rover capable of exploring the Moon’s darkest craters — all without posing a fire hazard. 

A team of NASA researchers is working to make all that happen. The project is called Solid Power for Extreme Environment Adaptability and Resilience in Space (SPEARS), and it could provide NASA with an important tool to help power humanity’s sustained presence on the Moon through the Artemis campaign. 

“Batteries have become an important part of our lives here on Earth, which enable our laptops, cell phones, power tools, and even our vehicles,” said Donald Dornbusch, principal investigator for SPEARS at NASA’s Glenn Research Center in Cleveland, where the project is led. “We will need them on the Moon, too, and these batteries will be required to operate reliably and safely in this harsh environment. That’s why we’re working on this technology.” 

Splashy problem, solid solution

Traditional lithium-ion batteries like those in your cell phone and laptop have a critical weakness: they rely on liquid electrolytes. Cool a conventional battery to the Moon’s nighttime temperatures, and that liquid would freeze, potentially damaging the battery. Heat it up too much — say, to daytime lunar temperatures of 212 F (100 C) — and it won’t work until cooled. Expose the liquid to the vacuum of space, and it evaporates. 

SPEARS batteries solve these problems by replacing the liquid electrolyte with a solid ceramic- or polymer-based material. This change could unlock several advantages. First and foremost, they could operate in the heat and extreme cold. 

During recent thermal vacuum testing at NASA’s Langley Research Center in Hampton, Virginia, small prototype battery cells operated well up to 176 F (80 C), down to minus 76 F (minus 60 C), and with slightly reduced performance down to minus 112 F (minus 80 C). 

“We proved for the first time that these cells can work down to minus 80 degrees Celsius,” said Yi Lin, SPEARS testing and research lead at NASA Langley.  

Lin also said he’s confident they can improve performance and maybe even expand that range in coming years. 

The batteries need to remain reliable through exposure to the Moon’s wild temperature swings between day and night. The thermal vacuum testing showed that after exposure to temperature extremes from 212 F (100 C) to minus 274 F (minus 170 C), SPEARS batteries don’t sustain damage.  

Not even solid-state batteries will function while they’re at a temperature as low as minus 274 F, but because solid electrolytes don’t freeze like a liquid, the batteries can survive the extreme low temperatures.  

In order to get the batteries working again after exposure to such cold, small heaters come into play. SPEARS batteries wouldn’t need to be kept warm all the time, just warmed up to operational temperature. That could reduce the need for heavy thermal management systems in spacecraft and lunar habitats, allowing for lighter designs, lower costs, and longer mission durations. 

Power for Moon, Earth

The applications for these solid-state batteries are nearly limitless, from small tools like drills that must operate in shadowed lunar craters, to rovers and emergency power packs for astronauts. They also could provide power solutions for long-duration scientific instruments. 

“We can tune the chemistry by using different electrode materials,” said Lin. “Just like the chemistry in your earbuds is different from the chemistry in your phone, which is different from the chemistry in your car, all these chemistries can still function with a solid electrolyte. We can tune for energy, tune for power, tune for durability, depending on the application.” 

While SPEARS is designed for space, the technology could be spun off into Earth-based applications. In fact, SPEARS evolved out of a previous battery project Lin and Dornbusch worked on that focused on aeronautic applications. 

“The potential market for solid-state batteries is very broad,” said Ji Su, a polymer materials scientist and the task lead at NASA Langley. “Automobiles, cell phones, communication devices, drones — anything that needs a portable power supply.” 

The SPEARS project began in 2026 with funding through the Advanced Research and Technology division within the agency’s Research and Technology Mission Directorate. The project is set to focus on technology development in its first stages before potentially shifting toward commercial collaboration. NASA’s Ames Research Center in California’s Silicon Valley is working to develop flight hardware such as test boards and electronics to help prepare the SPEARS batteries for spaceflight and test them in space environments. 

NASA is leveraging its expertise and enhancing its test facilities to help address a rare but persistent aviation hazard: icing that occurs when aircraft encounter unusually large, very cold water droplets in clouds.  

The problem, known as “supercooled large droplet icing,” occurs when aircraft fly through clouds containing unusually large drops of water that are very cold but remain liquid. When a plane passes through those drops, they can rapidly freeze to surfaces that are not protected from ice buildup.  

With a series of tests in the Icing Research Tunnel at Glenn Research Center in Cleveland, NASA researchers are helping U.S. industry better understand the phenomenon. 

Supercooled water is common in clouds – droplets can go below 32 degrees Farenheit but not freeze unless they encounter dust or other tiny particles around which they can crystalize. Aircraft are designed to encounter typical icing conditions where droplets range from 2 to 100 microns in diameter (for comparison, a human hair is about 70 microns wide). But in rarer cases, clouds can contain supercooled large drops up to 2,000 microns in diameter (if you’ve ever been caught in freezing rain, you’ve encountered these droplets at ground level). These much larger droplets can hit or splash to the aft of an aircraft, including areas behind conventional ice protection systems.  

The aviation industry relies on engineering tools to help design their aircraft. Current tools work well for typical clouds, but engineers have questions about how well they account for the physics of supercooled large drops. To help answer those questions, NASA is working to enhance the equipment it uses to generate and measure experimental clouds for testing in the Icing Research Tunnel.  

NASA researchers have experimented with brand new probes that help calibrate the sizes of the drops in the clouds the tunnel produces. The probes can “see” drops larger than 45 microns and perform a real-time analysis of their sizes. NASA will compare these results, a laborious technique of post-processing droplet size image data from the tunnel. The results will be mated to results from a different probe that measures droplets smaller than 45 microns. With this, the complete droplet size spectrum is known. 

The test campaign marks an important milestone for the Subsonic Flight Demonstrator project, part of NASA’s Research and Technology Mission Directorate. Detailed analysis of the collected data continues, and NASA’s project team will share results with the broader aerospace community once complete.