Battery
In GT there are many types of batteries. Firstly, batteries divides into categories of power electricy: ULV, LV, MV, HV, EV, IV, LuV, ZPM, UV, UHV. Secondly, batteries divides into categories of volume: small, medium, large. Thirdly, batteries has 5 types of material: sodium, cadmium, lithium, sunnarium, infinity. There are also a single use LV and MV batteries: acid and mercury batteries. The batteries hulls is craftable in workbench or assembler, but to craft batteries from hulls you have to do it in canning machine. If you in end-game you can craft ultimate batteries that store 10^9 EU!