How to charge batteries

I purchased a 2002 e4 car the batteries have been changed out to lead acid marine batteries. As far as I can tell the charger is original. Do I need to leave the charge pulled up with the car is not in use?

  1. If the original batteries were GEL cell you have to make sure the charger has been set up for flooded.

2 If you have a Zivan charger and it has the “modified” sticker on it your all set and can leave it plugged in.

Why is it important to have the charger set up for the Flooded cell batteries.

Flooded batteries require a more agressive charge algorithm to stir the acid and fully charge the battery.

If you don’t fully charge you will notice a rather rapid loss of range. 30+% over 6 months.

An indication of this is rapid fall off of capacity over the first couple of miles, say from 100% to 75% then tapering more slowly.

Another check is to measure specific gravity 3 hours after charge. If voltage is 100% and gravity is down this is a sign of continued undercharging and sulphating has started.

If you catch it early enough your dealer can desulphate your batterys and bring them back somewhat. (allow a week for this process)

If your battries are not bubbling slightly, when charging, you need to have your system checked.

Please be specific when saying “lead acid battery”, as GEL, AGM, and flooded are all different types of lead acid battery. Some Zivan NG1 chargers will automatically restart. The “micro upgraded” label does not always mean that the charger will automatically restart. All four of our Zivan’s were upgraded close to a decade ago and none of these will automatically restart. Check with Zivan USA to confirm and to avoid ruining an expensive set of batteries.


The batteries are Interstate group 31 batteries.

If the caps on the batteries are easily removable, they are flooded lead acid and the Zivan NG1 should be set to position “F”. A charger can be made to cycle by using a plug in programmable timer such as those people use to make their home look occupied while on vacation.