oops! wrong batteries, 64v instead of 48v

[BobEv]

Hi folks:

We have 2 club car turf cars both 48v. But one is older & uses 8 v batteries, the other uses 6v. Volunteers at our local little league mistakenly ordered two sets of 8v batteries and put in 8x8v=64v into the 2007 model QB0730-786206 turf car. Now its pretty much dead. So i eliminated 2 batteries to bring it back down to 48v (does that work long term?) charged the batteries with a 12v car charger carefully to get them back up in the 7-8v range - it still does not charge

but the cart is dead, i get one or two bars on the charge indicator in the dash, can here a click when depressing pedal, but no reverse buzzer & no movement at all. And the charger does not kick in when plugged in. teh fusible link & fuse is good...

anyone have any experience with this type of issue?

[kgsc]

If you put 64 volts through the controller, obc and solenoid it could have cooked all of them. Obc is what turns the charger on so that first. Should be a fuse right next to the charger port in a yellow case. Check that first.

[ThreeCW]

BobEv,

An 8 volt battery fully charged is about 8.49 volts. So 8 x 8.49 volts would have given you about 68 volts. Most modern 48 volt controllers will shut down at 60 volts ... so hopefully you did not damage the controller. Note also that a 48 volt pack will charge at a peak voltage of about 65 volts ... so again, hopefully your controller is still intact.

You mention that you carefully charged your batteries with a car charger to get them back up in the 7 - 8 volt range. A really dead 8 volt battery (below 20%) would be 7.77 volts. But for maximum life, you want to limit a lead acid battery discharge to 50% which is a static voltage of 8.07 volts. See the attached battery state of charge chart for more information.

You question if 6 pieces of 8 volt batteries can be used long term in a golf cart ... it is no problem what so ever ... most 48 volt carts are equipped this way ... it does not matter if it is 4 x 12 volts, 8 x 6 volts or 6 x 8 volts ... it is all 48 volts.

When you got your "new" 8 volts batteries, they should have been supplied to you in a nearly full state of charge (80% or better) which means 8.33 volts per battery or higher. Getting a new battery below this voltage is a bad sign ... that is may have been stored for a long time without charging ... which can result in battery sulfation and possibly permanent damage.

If your batteries are actually in the 7 - 8 volt range, they would be significantly discharged and that could be why your cart is not operation.

Fully charge your pack (best with a 48 volt golf cart charger), allow the battery voltage to stabilize for 12 to 24 hours and measure the voltage of each battery to 2 decimal places ... i.e. 8.49 volts (or higher). Then try your cart again.

[BobEv]

thanks for the tips, ill get a little more charge in each battery, trying not to overcharge them, and yes i understand how letting them fully discharge is bad for them ... again, I did not do this, just my mess to try to clean up ...btw fuses are good, the one in the yellow holder & the solder like fusable link ...