Battery Performance

[Jtr8151]

Yet again, I look to you all for support, as I was quickly provided with valuable feedback on my last question.

I recently purchased a 2015 Precedent 48 volt with the notion that the batteries were bad, great deal, so I didn't mind having to replace them!

Charged the batteries last night to full, put it on a meter this am and was getting roughly 8.4 volts per battery and 50.8 volts on the pack. I then took the cart for a ride and got about 15 minutes out of it before the battery light came on and then began to flash, this was expected as I was informed the batteries had exceeded their life span.

I then again put the batteries on the on the meter and got between 8.0-8.2 per battery and 49.5 volts total. Again the cart battery light had came on and the cart slowed down significantly. However, my concern is that maybe it isn't the batteries as I was still getting readings over 48 volts?

I'm new to this, and I'm sure I'm missing something but I am just concerned that maybe there is another issue outside of the batteries with those readings? I do have a set of Trojan T-875 on order but would like some feedback before I get those installed.

TIA!

~Justin

[swm63]

Since you've stated that the batteries should be bad, and that's what it sounds like, I'll bet you have one or more in the pack that's falling on its face when under load. A good way to test is with a DVM connected to one battery. I'd start with battery number one. (Main positive) and continue the test on all.

With the DVM connected to the battery, (I just use alligator clips attached to the DVM) drive an area that has a slight hill. Note the beginning voltage before you start and what it drops to when climbing the hill. Repeat this test on all batteries in your pack. Record your results for each battery and you'll soon find the one or ones that are dropping a lot more than the others.

If you find this is the problem, keep in mind that it's always best to replace the whole pack after you find the culprit.

I have a circle drive in front of my house and one side is steeper than the other, so it's easy to run this test.

Good Luck.

[Sergio]

I think what You are missing is that a fully charged 8v battery should be around: 8.50v and at 8.0v they are pretty discharged (less than 50% capacity left).

A weak golf cart deep cycle battery can also show a good voltage due to something called "Surface Charge", but as You remove energy from the battery the voltage drops pretty quick.

The link below has the State of Charge (SOC) vs voltage table for 8v batteries and other battery information.

http://www.buggiesgonewild.com/elect...ml#post1426529

[yawood]

You've probably found this chart by now but here it is again.

[Jtr8151]

Awesome, once again, I greatly appreciate the feedback!