Ideal AH for 8V Batteries

[kfortier5]

Hey everyone,

My parents just gave me a '99 Club Car (48v). It's been sitting for 1+ years without charge. The batteries are bulging at the bottom and there is a lot of corrosion. All batteries are reading almost 0v, so i'm pretty sure the're toast (correct me if I'm wrong).

I'm new to the golf cart world, but have been doing a lot of reading on this site and elsewhere. I read that the ideal AH for a 6v battery is about 225. But I can't find a similar recommendation for an 8v battery. At first I thought it would be the same, but similarly priced 8v typically have 160-180 AH.

So, the question is: what's ideal for an 8V? I won't be using it that often -- a couple times a week for less than 2 miles each trip. I have a Series type motor.

[Hunter450]

Any 8 volt golf cart specific battery will serve you well. My first choice would be Trojan T-875's. I have 4 year old Duracell 8 volt golf cart batteries from Sams Club that have been good batteries. In your case, its more about maintenance than reserve capacity.

[BBBHC]

I would not mess around with any batteries that are bulging. They are not long for this world at best, will probably start leaking, if they are not already, not to mention possible worse outcomes. Get rid of them and get some new batteries.

[kfortier5]

Thanks to you both.

I found some T-875s for $125 ea, which doesn't seem bad since Sams wants about $110 for the Duracells.

Definitely getting rid of these old batteries ASAP. BBBHC, what are the possible worse outcomes? Asking because right now the cart is in my garage. Any fire risk keeping it there until I get the batteries swapped? Also, any precautions I should take getting the old bulging batteries out? I did order a battery lift strap so I can keep my hands off them...

[BBBHC]

Leaking acid is the most likely outcome. They can burst, sending acid flying around, but that is not that common. Definitely don't charge them. Maybe some rubber gloves, eye protection and cover skin, just to stay on the safe side of things. As for fire, I'll let someone else answer that, that is a bit outside of my knowledge/experience with FLA batteries.

[WalterM6]

To answer your first question. 225ah and 170ah batteries are identical just a slight difference. The 6v 225 ah battery capacity is 1.35 KW and the 8v 170ah is 1.36 KW.

[Fairtax4me]

A battery sitting at 0V may be able to recharge but it wont have nearly the capacity that it once had.
Good thing about a totally dead battery is that it's practically inert. The most harm it will do is if you drop it on your foot. There is still acid in the battery but it's mostly water by this point. As a battery discharges the sulfur in the electrolyte deposits on the lead plates, which decreases the acidity of the solution. It will cause expansion of the plates over time, which is what causes the sides of the battery to bulge. That's a normal part of the aging process for a lead acid battery. The bulge isn't an indicator that the battery is dead, and other than decreased charge capacity it really doesn't hurt anything. I've dealt with a lot of batteries in the automotive profession over the last 10 years and have never seen a battery leak because of bulging.

[kfortier5]

Thanks, Fairtax. That makes me rest a bit easier! Still not going to try to charge them though. Just going to start with a fresh set so I can troubleshoot the rest of cart a bit easier.

[scottyb]

To answer your original question, ideally you would get a 190 ah 8v battery. Crown offers one and so does Trojan

[ag4ever]

My cart sat in a closed shipping container in central texas from December '17 to September '18. It was connected to the factory charger, and it had boiled the batteries where 1/4" of the plates were exposed. All voltages were 0v, dead flat.

I refilled the cells with distilled water to cover, then alternated charging each battery with a 12v car charger (good copper winding type, not the new electronic ones, and not a maintainer) for about 5 minutes each.

I was able to get the voltages up high enough to activate the cart charger. I then did a bunch of charge cycles, and continued to boost them with the 12v charger intermittently. The key is to get the acid agitated and remixed up, intentionally letting it boil to get the mixing action. Don't let the acid levels drop below the top of the plate though.

I was able to restore them to about 80% capacity per the typical FLA Charge Chart.

When running the cart, I could get about 15 miles out of it running at 100% throttle 90% of the time. (Running non-stop for 1 hour at 15-19 mph with slow downs to turn around.) At the end of this run I was down at 55% state of charge.

The cart would have decent power in the first 5 minutes, then after that it felt flat. It would go, but did not have the punch it should have.

These were 3 year old batteries.

You might try charging them. Could buy you some time while you search for a new set of batteries.

In the end I said, "Forget this mess, I'm going lipo!"