Golf cart charging

[/pine]

L/A deep cycle batteries should never be allowed to get below a 50% charge...
Trying to use 4 different chargers would involve un-connecting the cables that put the batteries in series...this would have to be done for every charge..a PITA...

FWIW...When the RXV carts (fly by wire) were introduced they came with 4 12V batteries...they have switched to using 6 8 volt batteries...

Also FWIW and a possible cause for some of the OP's problems...
The water level in the cells should only be 1/4"-1/2" above the top of the plates..it is common to over fill the cells...(this is from Crown)....

L/A batteries should be charged before adding water...

 

[Grumpycat]

….but fundamentally, is there any problem with using 4 smart chargers simultaneously, one on each battery? I wouldn’t think so, but maybe I’m missing something.
Seems like it might prevent overcharging.

Yes, you could. The outputs should be transformer isolated from the AC mains so no issue connecting the negative of one charger to the positive of another. That you shouldn't have to disconnect the batteries from the golf cart.

For safety's sake use a DVM to check for continuity between the output leads and the AC plug pins. The most likely gotcha would be between ground pin and the black lead... if you have a grounded AC plug. Megaohms is fine, what we are worried about is 10's of ohms.

 

[KristianBouwkamp9]

There is most likely water/acid on the floor, causing your charger to overcharge. I was advised to put a voltmeter on the individual batteries. When charging, the voltage should not exceed 14.5V, and then you can get the results you want. I also owned a 2014 EZGO RXV from 2017 to 2019 and sold it due to frequent charging failures. Later, when I looked for new batteries for my vehicle on Amazon, I found out that many owners of this model have the same problem as you. So it's a very common issue.

 

[rbstern]

Follow up on this topic. About a month after I started this thread, lightning hit our garage. Fortunately, nothing caught fire. But there was a lot of damage (garage, house, office, vehicles, power co transformer, electronics) . Took a couple of months to repair everything.

One of the casualties was the 48V golf cart charger. The golf cart wasn't damaged. I replaced the charger with a four bank Minnkota MK440 unit, installed on board. I replaced the batteries with...wait for it...four Everstart Max group 29 deep cycle batteries. At the time this was going on (October 2021), nobody within 100 miles of me had 12v golf cart deep cycles in stock. Had calls in to numerous cart dealers and battery shops.

The Everstarts were cheap. They weigh about 20% less than equivalent Trojans or Crowns, so they don't have as much capacity. I figure if I can get two years out of them, it will be worth it. I've had great service out of deep cycle Everstarts used with trolling motors, so I like the brand (manufactured by Johnson Controls).

9 months in, it's been a success. The Minnkota keeps the batteries individually topped off. We plug it in after every use without fear of overcharge. The range is excellent; way more than we use. In fact, I've never had the charge meter drop below about 70% during our busiest days of use of the cart. We use the cart more now because of our confidence in the battery condition. I spend zero time on water maintenance. No more new acid stains on the garage floor.

Will post updates on battery longevity. If they falter in the next 15 months, I'll go back to the expensive batteries from the top line makers. If I make it to the 24 month mark and beyond, I'm likely going to keep using these as a permanent solution. Not thinking about water maintenance is a relief.

 

[Rayrla]

L/A deep cycle batteries should never be allowed to get below a 50% charge...
Trying to use 4 different chargers would involve un-connecting the cables that put the batteries in series...this would have to be done for every charge..a PITA...

FWIW...When the RXV carts (fly by wire) were introduced they came with 4 12V batteries...they have switched to using 6 8 volt batteries...

Also FWIW and a possible cause for some of the OP's problems...
The water level in the cells should only be 1/4"-1/2" above the top of the plates..it is common to over fill the cells...(this is from Crown)....

L/A batteries should be charged before adding water...

/pine has made some very important comments regarding maintaining golf cart lead acid batteries.
I have a 2006 club which came with 4 12 volt batteries which were very short life batteries. Very poplular with the 4 12volt battery Club Car owners was a change to either 6 or 8 volt 48 volt systems. I did this after my first 12 volt battery replacement batteries died. My 2008 Club Car Carryall came with 8 6 volt batteries which are still in that cart. Maintenance is the key.

 

[Gale Hawkins]

Switch to Lithium Iron LifePO4 and never look back!

​

Another paradigm shift game changer that is hard on the old and poor. Our EZGO 36 volt cart is starting to require watering so replacing them again will be the short term fix. Batteries in series are are never better performing than the worse one in the series from my experience. I need to get the 24 kWh Leaf pack out our 2015 parts car and see their health condition. It's body at 27K miles was mint inside and out. Eric insurance had totalled it due to unknown electronics issues. We suspect a surge may have occured.

 

[dmccarty]

Charging voltage will differ depending on the battery type/chemistry. Putting a charger for a lead acid battery on a LiFePo battery is very likely going to cause problems. One needs to look at the required charging voltage for a given battery and make sure the charger is charging as required.

I know of a brand new 50ish foot long boat, whose lead acid batteries blew up, almost certainly from over charging, which caused the boat to sink while doing a multiple day open water crossing. The most probable cause for the batteries exploding was incorrect charging parameters.

There are "drop in" replacement LiFePo batteries. Be very careful with these batteries. This link will explain why, Drop-In LiFePo4- Be an Educated Consumer

While the Marine How To website is focused on boats, the information applies to many other application. The website has quite a bit of information about batteries and chargers written by an electrician who is very experienced.

Later,
Dan