Testing out B4 puchasing new Batts
 

Mornin all. Ok so I got this 1997 TXT 36 volt cart. I installed 3 12 volt batteries taken from my cars so I know they are good. Cart runs nice for about 15 or 20 minutes then when the battey pack voltage drops to around 29 volts, no movement. Let is rest a few seconds, pack voltage comes back up to 36-37, cart will go a very short distance again. When the cart stops, and I attempt to go again, there is a strange noise like splines slipping against each other. I checked the hubs/axle shafts,,OK, pulled the diff cover,,OK. No mechanical issues found. I would have thought that when the pack voltage drops the cart would simply go slower and slower and eventually stop, but not make this strange noise. Any thoughts?

Also, I've read here a couple times that a person would be lucky to drive a cart more than 30 minutes with 3 good 12 volt batteries. Is there really that much of a difference between these and 6, 6volt batteries?? WHY? I don't understand where the difference lies.

Thanks

Re: Testing out B4 puchasing new Batts
 

12 volt car batteries and 12 volt deep cycle batteries are two different things, you will get alot longer run time with deep cycle. The cart will not run when battery voltage drops below a certain amount. In your case 29 volts is it. The difference between the 12 volts and the 6-6volts is the amount of available amp hours. I'm sure someone will chime in with a more detailed explanation.

Re: Testing out B4 puchasing new Batts
 

If that is the DCS cart you speak of in your other threads, I'm surprised the controller is still working after taking the battery pack down to 29V.
(DCS controllers have no low voltage cut-off safety and are susceptible to low voltage damages.)

Sitting that aside, there is a lot of difference between Car batteries (SLI) and golf cart batteries (deep-cycle) and there is a major difference between 3 X12V and a 6 X 6V battery packs, both being made up of deep-cycle batteries.

SLI (Start - Lights -Ignition) batteries are design to produce a very high number amps for a short period of time and immediately be recharged. They will not survive many deep discharges, so your formally good car batteries aren't so good any more.

Deep-cycle batteries are designed to produce a moderate number of amps over a long period of time. They can be deeply discharged hundreds of times.
The physical difference between the two is the number and thickness of the plates as well as many other things.

Marine batteries typically fall someplace between the two extremes.

As for run-time, the typical 6 X 6V deep-cycle pack has about 225 Amp-hours, and the best 3 X 12V deep-cycle pack is about 155AH.

That works out to about 8.6kWh for the standard 6 X 6V pack and about 5.9kWH for the best 3 X 12V pack, or about 2/3 the run time and the 12V batteries will have to be replaced sooner because the are being loaded heavier.