Wrong. Electricity can be split. You could power many things with it at the same time.
If it's all in the same suit, or the same base, or the same ship, you're basically just powering the suit/base/ship.
And saying the device doesn't have any use is inaccurate. It has multiple uses. Hallucination attack, possible power source. It just doesn't have any you like can use. If you really want, you could even sell it to Milno for tokens.
As to the first use: Barely any use, high probability of backfire, and no way in Hell is Grate either going to throw his valuable (and expensive) alien artifact at someone or enter melee range.
As to the second: What would Grate have to power, and how could he tap it?