Deep Cycle battery polarity issues (24v)

[zippy83]

Hi Everyone.

I have been having polarity issues with my 24v trolling motor system. I got a brand new boat in 2021 and 12 1/2 months later I had my first factory battery issues (not covered by warranty) with polarity being reversed. Someone here mentioned to change out both batteries in fear that the other one might follow, so I did. I got two brand new same spec batteries. About 6 months ago one of those batteries had the same issue. I got it replaced by warranty, and I also replaced the other one as well. yesterday I was looking at my trickle charger and sure enough one of them is showing reversed polarity.

What could be the issue here. This is my first 24v system.. It is hooked up properly, I am using a trickle on board charger every time the boat enters the garage. This is becoming a pain in the ass with my first Canada trip later this month.

If anyone knows what I'm doing wrong please let me know. The dealer is not helpful at call since the warranty has expired on the original bateries.

Thanks
Zip

 

[dubs283]

Is your trickle charger a two bank with batteries connected individually and charger on the proper setting for the type of batteries?

 

[dingbat]

It's not a battery problem.
It's physically impossible for a flooded acid battery to reverse polarity. I'm guessing it's the charger is barking at you

Dual bank, 12VDC or 24VDC charger?
If 12vDC, wired as below?

 

[zippy83]

Is your trickle charger a two bank with batteries connected individually and charger on the proper setting for the type of batteries?

It's a three bank charger, and yes all batteries are connected individually. As far as I can tell when I brought the new boat the configured charger for the batteries.

 

[zippy83]

It's not a battery problem.
It's physically impossible for a flooded acid battery to reverse polarity. I'm guessing it's the charger is barking at you

Dual bank, 12VDC or 24VDC charger?
If 12vDC, wired as below?

View attachment 383227

right now I have the problem battery outside. When I look at the battery checker tool (separate tool) it shows me that Negative is Positive and positive is negative. When I take my external charger and hook it up to the battery as it should be (positive to positive, negative to negative) it barks at me and says that the battery is bad. When I put positive from the charger to the negative terminal on the battery and neg from charger to positive on the battery is start to charge for a few min and then it starts to complain again.

 

[dubs283]

As far as I can tell when I brought the new boat the configured charger for the batteries.

Learn about your on board charger. I'm guessing you still have the owners packet?

Hopefully there's a user's manual for the charger, read up on it, inspect and adjust accordingly

 

[mike_i]

What "battery checker tool" are you using? Do you have a digital voltmeter?

right now I have the problem battery outside. When I look at the battery checker tool (separate tool) it shows me that Negative is Positive and positive is negative. When I take my external charger and hook it up to the battery as it should be (positive to positive, negative to negative) it barks at me and says that the battery is bad. When I put positive from the charger to the negative terminal on the battery and neg from charger to positive on the battery is start to charge for a few min and then it starts to complain again.

 

[Scott Danforth]

I have had dead batteries that were charged backwards (sibling in charge of charging the battery)

Hooked a 12 volt light up to the battery, let it drain down to zero, then charge it correctly

I would be looking at the battery charger and wiring

 

[zippy83]

What "battery checker tool" are you using? Do you have a digital voltmeter?

Yes... it is a digital voltmeter.

 

[zippy83]

Learn about your on board charger. I'm guessing you still have the owners packet?

Hopefully there's a user's manual for the charger, read up on it, inspect and adjust accordingly

I looked into the charger that I have NOCO Genius Gen 5 x 3 on board charger. it is a 3 bank charger, each bank charges the 12V battery individually so if the settings are correct (to chanrge a 12V battery and not a AGM or Lithium battery) it will charge properly. There is no 24V option since it charges each battery separately.

 

[zippy83]

I have had dead batteries that were charged backwards (sibling in charge of charging the battery)

Hooked a 12 volt light up to the battery, let it drain down to zero, then charge it correctly

I would be looking at the battery charger and wiring

here is the wiring...


The only other thing I can think of is the battery charger... I have contacted the dealer and they said that they can test the battery charger to see if there is something wrong with it.

 

[airshot]

I would definately have it tested !!