I have replaced the lead acid batteries on my electric scooters with lithium batteries and was looking to get a new charger so I figured it would be a bit faster than my charger at 3 amps (for 24v). at 1.5 Well it's not faster in any shot. It will not charge any battery, 12V or 24V, with more than 1.5A, so it is no faster than my original charger. It also stops charging at a lower voltage than my standard charger, so I don't get as "full" when using this charger as I did with my original charger. Two 12V 10Ah batteries connected in series (24x @ 10Ah) are charged from 27.8V to 28.2V with my original charger, but on this charge it only reaches 27.1V before it turns off, which is worth a few miles on the road to me. The repair function seemed to help revive the failing 12v battery, but that was the only thing that seemed to do what was claimed. Otherwise I would say this is not a very good charger for my purposes and definitely does not perform as advertised. 2 stars because of the repair function.