Charger didn't shut off

[GOLFERDAN]

After using the cart yesterday, I parked it at 75%. (Batteries still in break in period) I plugged the charger in and left as I usually do. (The cart stays at the golf course.) I meant to check the water in the batteries before I left but forgot. So I returned to the course today to check the water. It was fine but the charger still hadn't shut off. It was on for approximately 21 hours. The voltage on the soc meter was at the normal charge voltage. (42 or whatever it normally is. I can't remember for sure.) I unplugged the charger and checked the individual battery voltages to see if one was dragging the pack down. They were all at 6.8. The ammeter on the charger was a couple of lines from 0. I've never seen one charge for this long without shutting off. It didn't seem that they were overcharged but I wasn't there long enough to let the voltage settle to the normal 38.2. I'm concerned that the charger isn't shutting off when it should. And the cart, as I said stays at the course so I'm not there to monitor it. Is this cause for concern or can it be normal to take this long to charge. By the way, it's a 36 volt with 2 week old Crown Cr235"s. This was my third round of golf with them.

[Golferdave]

Yea
21 hours is a long charge cycle but might need that much time to get the
batts up to voltage.( common to be over 45 volts when charger is operating)

You plug it in after every use ?

What's your temperature overnight ?

Charger was down to low amps, usually means the control side is working ok.
What's charger model ?

Good wires clean battery charger connections?
Signs of heat on the charger wires, connections ?

If you are away for days at a time,
One option, install a timer on the ac cord plug-in :
https://www.amazon.com/Intermatic-FF.../dp/B000LDEO26

[GOLFERDAN]

First of all, Thanks for the quick reply, Dave. Yes, I charge it after every use. These are brand new batteries (4th charge cycle), so I haven't run the below 75% yet.

It is a stand alone Powerwise. As I said, this is the 4th charge cycle on these batteries and I used all last season on the older batteries. I don't recall it ever staying on this long. I play most every day and it's always off by the time I return to the course the next morning.

All battery wires are new, clean and tight.

No feel of heat.

Temperature in the 40's.

[Golferdave]

The new Batts are still breaking in
I betting you are OK

keeping a close eye on them is good
but give it a few more charge cycles before you get overly concerned

Getting warmer will help too.
It's a chemical reaction & is slower at colder temps.

Here we use battery blankets on car batteries when below 0°
Batts are rated somewhere around 70°f

[Rickochet]

Any chance that there was a power outage at the course?

[cgtech]

Originally Posted by Golferdave

The new Batts are still breaking in
I betting you are OK

keeping a close eye on them is good
but give it a few more charge cycles before you get overly concerned

Getting warmer will help too.
It's a chemical reaction & is slower at colder temps.

Here we use battery blankets on car batteries when below 0°
Batts are rated somewhere around 70°f

Lead batteries are rated at 80°f, de-rated at Temps below 80, and score better "than rated" at Temps above 80.

[GOLFERDAN]

Thanks guys. Hadn't thought about the power outage thing. We did have a storm or 2 go through the area. I read on the forum about the possibility of dirty/corroded charger port connecters causing the charger not to shut off. So I will definitely clean them tomorrow. Will keep a close eye on the cart as much as possible since the it stays at the course. But since nothing was hot I am going to leave it plugged in after the next time I use it.

[GOLFERDAN]

Trying not to be concerned but I checked it yesterday again. The cart sat unplugged overnight. The SOC meter showed 38.8 volts. I plugged the charger in just to see if it would come on. It did. I left it on and watched as the pack voltage went to 48.2 and still climbing. The ammeter was at 0 and the charger still wouldn't shut off. Left it unplugged again. Don't have any other battery cart to try it on so I may take it to a local shop to see if they will try it on a cart.

[GOLFERDAN]

Update..... I believe you all are correct. Took a chance, left it plugged in at the course. Not sure how long it stayed on but it did turn off. Tested it 2 days in a row and it's fine. It does, however, charge the new batteries to a bit higher voltage. After sitting for 24 hours, the pack showed 38.5 volts.