I'm helping a buddy doing some work on one of these trucks for one of his customers. Truck would barely move when it came in.
The truck arrived with 7 new traction batteries plus one AGM battery for the cab. We found that six batteries were over 12 volts each and one was about 5. We took out that battery and put it on an external charger, then load tested it with an inverter driving some lights. The battery also tests fine on a conduction type tester.
Turns out that the owner (or previous owner) had not only added an extra traction battery but put the charging cable between the sixth and seventh battery. Six batteries were charging but the seventh was depleted since it wasn't being charged - which is why the truck would barely move.
I'm assuming it was shipped from the factory with six batteries because the charger's output is about 89V - perfect for six batteries but not for seven. The charger's LEDs also indicate proper charging.
Once we removed the extra battery and corrected the wiring, charging voltage before shutdown reaches about 14V across each battery and all batteries are charged. The truck now runs.
So here's the question: what were the AH ratings of the original batteries? The owner of the truck put in new batteries but has blocks of wood added to take up space between the battery and the clamps, so it looks like the case size of the original batteries were larger. The truck runs well on flat surfaces but struggles on inclines almost coming to a stop on a local street with a small hill. The current owner bought the truck with dead batteries so he has no idea what kind of performance this truck has on hills.
Any insight appreciated.
EDIT: I joined this particular forum because it was about the only one with any mention of ZAP vehicles, plus I have a rolling '66 Mustang 2+2 I would love to convert to EV.