How load test 6V Golf Cart Batteries When Out Of Boat

[tranquil]

Ahoy!

Given that a battery's plate at the top could be good but not the case in the middle or bottom - any ideas on how to load test a 6V ECG2 Golf Cart Battery when not on the boat? This deep cycle doesn't list CCA and I've been to 3 auto parts stores that don't know how to test them. One said they need and don't have a 6V tester. The other 2 just made up and input CCA's into their tester, resulting in "good" readings. Not numerical results, just "good" or "bad" - which I find unacceptable. I need real data.

Since boat is on the hard and not accessible, I ordered a Hygrometer and KONNWEI KW208 12V Car Battery Tester, 100-2000 CCA Load Tester Automotive Alternator Tester Digital Auto Battery Analyzer Charging Cranking System Tester for Car Truck Marine Motorcycle SUV Boat-which will arrive today. I've researched Golf Cart testing on the internet and all require the batteries in the golf cart for load testing - by acceleration while on a ramp.

Yes - all the signs during the summer of "growing to bad" - long time charging, cant start engine on just the 4 6V golf carts unless connected to shore power ( I don't do this except wanted to test - have a start battery). Cables and terminals check out clean/good. Had electrical power outage issues with the outlets at the head of the dock toward the end of the season=problems began. As what I think is the result, the start battery was bad and I got it exchanged - as all 5 batteries were purchased last May. It was easy to test and proved was in the bad numerical range. I suspect the others are also getting bad but appreciate input on how to adequately test AND obtain numerical results. PS cant go aboard till spring and battery charger seems to be ok/unaffected.

Thanks

[wolfe10]

I would contact Walmart, Sams, Cosco or any golf cart service facility.

All of them routinely sell and should be able to test your 6 VDC batteries.

Be aware that they must be fully charged to accurately test them with either a load test or hydrometer.

And, if all you have is a 12 VDC charger, hook up the 6 VDC's in series and charge them that way.

[Olivia Mae]

The reason you haven't been able to find someone to test your 6v deep cycle batteries is because it's not an easy task to do that. They have ratings based on a steady discharge at a measured rate, so you'll find a spec for discharge at the 20 hour discharge rate. That means, if you set up a test bench and discharge your battery at the 20 hour rate, it should be fully discharged at 20 hours. That is really the only way to test whether a deep cycle battery has the rated capacity, or something lower than that. The following link explains how to do this in detail, if you're interested. Personally, I find this more trouble than it's worth, though it would be useful info to have to track bank capacity year to year. A battery hydrometer can be used to test for cell to cell inconsistencies and pick up a bad cell, but that's about as useful as that test will be. A battery monitor, like the Victron Smart Shunt can also help you monitor battery health during use, and help keep you from overly discharging the bank.

https://marinehowto.com/under-load-batt ... ge-vs-soc/

[wolfe10]

The reason you haven't been able to find someone to test your 6v deep cycle batteries is because it's not an easy task to do that. They have ratings based on a steady discharge at a measured rate, so you'll find a spec for discharge at the 20 hour discharge rate. That means, if you set up a test bench and discharge your battery at the 20 hour rate, it should be fully discharged at 20 hours. That is really the only way to test whether a deep cycle battery has the rated capacity, or something lower than that. The following link explains how to do this in detail, if you're interested. Personally, I find this more trouble than it's worth, though it would be useful info to have to track bank capacity year to year. A battery hydrometer can be used to test for cell to cell inconsistencies and pick up a bad cell, but that's about as useful as that test will be. A battery monitor, like the Victron Smart Shunt can also help you monitor battery health during use, and help keep you from overly discharging the bank.

https://marinehowto.com/under-load-batt ... ge-vs-soc/

While absolutely correct, a quick "load test" at places that sell batteries will often show the same results-- if total 20 hr capacity is diminished, CCA load will likewise be diminished.

Said another way, a sulfated battery/one with a bad cell will flunk all tests.

[tranquil]

Scott and Brett - thank you for your replies and information!

I've been to Sam's where I purchased the 4 ECG2's 6 months ago. The mechanics are very young, dont know how to test without CCA data, input their own best guesses and the result is the battery is "good". All 5 batteries were hooked up as indicated in previous blogs- 4 ECG2 connected on one side and the start battery on the other side. I first switched over in 2011 and all the batteries lasted until Spring 2022 (pretty incredible)

The start battery easily tested bad and I suspect the 4 Golf Carts are bad, but need to prove it in order to get them exchanged under the current 1 year warranty, which expires May 1, 2023.

There are no listed golf cart service centers up here. I've contacted 8 different country clubs to see if they will share who maintains their golf carts & batteries, however, no response to date. Golf is seasonal here along with the related staff in most cases. I agree a 20 hour bench test would be extraordinarily difficult, but may be forced into it.

When my tester arrives I will hook up 2 sets and test as 12V, but wont I still need CCA's or another data point for an accurate test?

Ugh, such great batteries, rather what a great choice to replace the original batteries so I had no clue this would be so difficult.
Thanks

[yodagwb]

First and easiest test. How old are the batteries. If they are in the 4-year range (4.5 if you pull for the winter, 3.75 if you are in Florida) yes, they are going bad. You can just about mark it on your calendar.

Consider reading the Lithium battery thread.

[yodagwb]

Sorry missed that they were 1 year old.