I have gone and lost my exposure charger for my joystick and maxx lights, now I know I can buy a smart charger replacement for circa £18 quid but I have read they are a bit shodily made.

So are there any alternatives that will do the smart charging or could I just get one of the connectors and make cable to a USB 5v charger or will this just slowly cook and destroy the internal battery? (original charger 4.8v 1500ma)