A Raytheon team has developed vehicle armor that doubles as a battery – a breakthrough that could power electronics, reduce engine run times and lessen the military’s demand for costly, dangerous fuel convoys.

The armor, described in a September 2015 patent, works by layering bullet-resistant electrical conductors such as high-hardened steel with sturdy insulators such as ceramics. The result: Power goes through it. Bullets do not.

“My department manager, when he saw it, said, ‘Wow. Batteries that stop bullets,’” said Gary Wahlquist, one of the engineers named in the patent.

The batteries store the energy that vehicles generate while in motion. When the vehicles are stopped, the crew can switch to battery power, rather than having to run the engine just to power their on-board electronics.

The team’s research is among many ways Raytheon is working to improve the storage, control, and management of power, including a microgrid for the U.S. Marine Corps Air Station Miramar, and energy storage systems that can stash away power from renewable sources. The battery armor patent comes as the U.S. Department of Defense invests billions in energy-saving initiatives, spurred in part by deadly attacks on fuel convoys in battle.

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