It has no battery inputs and cannot take power from wires, requiring a Storage Unit nearby. It cannot work with Personal Storage, Battery Stations or Creative Storage. It needs the storage to be at least 70% full to charge and to be 30% full or lower to discharge. The machine's maximum EU/t input and output and discharge's efficiency depend on the storage tier. It cannot blow up.
https://github.com/TinyModularThings/IC2Classic/wiki/Electrolyzer