Past works in this direction
Last year, the Defense Advanced Research Projects Agency (DARPA) had awarded a contract to Raytheon to design and develop a wireless, airborne relay system to transfer energy in contested environments.
The project had a simple goal: giving US the ability to power anything on the battlefield from anywhere. It was a two-year, $10 million contract which asked the company to create a Persistent Optical Wireless Energy Relay (POWER) system.
The POWER system would have used a number of high-altitude unmanned vessels, which would be equipped with laser-based power receiving and transmission facilities.