Did I ruin my 2 year old batteries?

[gr8gmc]

I have a 2010 RXV with 4-48V Trojans installed new spring of 2015. After not having to add any water the first year and checking them often I neglected to check them often this summer and ran them low. I didn't expose the plates but water was just over them (less than a quarter inch) before I discovered the problem. To make matters worse, I ran the cart several times until voltage was down to 48.0 volts or less.

I've topped them off now. I've done a balance charge and they are really short on life. I can't play but 9 holes.

Are the ruined? What would bring them back to a more useable status?

[Seaquell]

The water should only be just over the plates ever.. more than that will just make a mess and won't help anything.
So the good news is that you never ran them to low on water

Maybe discharging them to much hurt them a little but not the water.

Do you have a good quality charger? Try another person's charger once or twice , to see if it helps .

[Volt_Ampere]

As they age, they will consume much more water than when they were new. You have to check them more often. No you probably did not ruin them!

[gr8gmc]

Ok. The life on these batteries went from being able to play 36 holes easily to barely making it 18, then finally not making it through 18.

How would I check the charger? My total voltage after a charge is 49.8 volts which leads me to believe it's doing it's job. I'll see if I can borrow another charger and get better results.

[Swan]

I check mine every two weeks if they need it or not .

[handtools]

According to the chart your batteries are not being fully charged.

CartsUnlimitedStateofChargeChart.png

[sltintexas]

what happens if the water gets below the plates? is that part ruined?

[yurtle]

Possibly. They have a mark inside, to indicate they are full. The easiest way to fill them is with a battery filling jug. They are cheap and will not overfill them. If you just barely cover the plates, they are a little low, meaning the acid is a little stronger than it should be. I don't know if that's causing them to not fully charge, but if you fill them after a charge, you won't "boil over" and lose acid as well as water.

[JohnnieB]

There are a lot of things going on here.

1. Running the batteries low on water without exposing the plates results in a higher acid concentration and shortens battery life expectancy, but not a major reduction.

2. The lower the average SoC maintained, the shorter the battery's life expectancy. Occasionally discharging to less than 50% SoC lowers the average considerably.

3. The typical battery lifespan is about 4 years, so 2 year old batteries are at mid-life.

4. The cooler the temperature, the less battery performance, and it is winter.

5. The 4 x 12V battery pack is amongst the worst design decisions EZGO ever made. At best, it has about 13% less storage capacity than the standard 36V battery pack of yesteryear.

6. Batteries that are chronically undercharged don't perform well and don't last very long.

I suspect some combination of all of the above apply.

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Your batteries may have some life left in them. I'd replace the existing charger with a DPI Accusense charger and charge the pack back to back several times. Then leave the DPI connected (Float charging) when not driving cart.

Also, I'd up grade to a 6 x 8V 48V pack which does have the storage capacity of the legacy 36V pack, and if higher capacity 8V batteries are used, even greater storage capacity. (See attached chart)