A GT battery box can output 64EU/t.
But for early game when you don’t have circuits you can use two dynamos + some fitting wire/cable.
Naked constantan wire has a 4EU/block loss if I remember correctly, so you can get a perfect 12EU loss.
Overhead view would be something like this, maybe. (E)lectrolyser, D(ynamo), x suitably thick constantan wire.
E
x <- with wire losses you`ll get 2x32EU/t (=64EU/t) after here
xxx
D D <- Each LV dynamo outputs 44EU/t if fed max RU/t
As for the battery, you can put a stainless steel faucet (or other acid-proof faucet) on a tank containing acid and right click the faucet with the battery part to fill it up manually.