“The Pentagon will pay a Silicon Valley-based research institute $4.7 million to develop a silicon/air battery capable of powering electronic devices and becoming “unobservable to the human eye” when activated,” USA Today reports.

The contract is part of DARPA’s Vanishing Programmable Resources program, which develops portable electronic devices capable of “capable of physically disappearing in a controlled, triggerable manner.”

“DARPA started the program to address the problem created by the spread of small electronic devices that could be left on the battlefield and found by potential enemies to be used against the troops they were originally intended to help. Such devices include radios, remote sensors or phones, DARPA records show.”