2016 - 39MB Batteries

[deepunderh2o]

One of my 2 batteries in my 2016 39MB is extremely hot. It boiled off about 1/2 gallon of water. The second battery is cool to the touch. The battery that is hot is the one that goes through the disconnect switch to the 12+ DC bus. The other battery that is cool has the lines going to the DC to AC converter to provide power to the residential refrigerator.

I have the Magnum Energy system panel. It was in float mod, charge rate was set to 100% charge (I have since changed it to 10%). I have also changed the charger from float to Stby. Voltage reading at the start has been 13.5 volts (Since adding water has dropped to 12.5) and remained at 13.5 volts even after putting the charger in Stby at about 0300 this morning. Upon returning home the battery was still hot.

The thing that caused me to notice all this was the smell that a lead acid battery produces when it is charging. (Spent about 23 years on Submarines and believe me I know about lead acid batteries!)

I am wondering if anyone else has seen or been involved with a situation with your RVs and the actions taken to correct the situation.

The biggest thing that I find strange is that one battery is cool and the other is hot to the touch.

Thanks in advance for all your input!

Geff

[hoosierguy]

Originally Posted by deepunderh2o

One of my 2 batteries in my 2016 39MB is extremely hot. It boiled off about 1/2 gallon of water. The second battery is cool to the touch. The battery that is hot is the one that goes through the disconnect switch to the 12+ DC bus. The other battery that is cool has the lines going to the DC to AC converter to provide power to the residential refrigerator.

I have the Magnum Energy system panel. It was in float mod, charge rate was set to 100% charge (I have since changed it to 10%). I have also changed the charger from float to Stby. Voltage reading at the start has been 13.5 volts (Since adding water has dropped to 12.5) and remained at 13.5 volts even after putting the charger in Stby at about 0300 this morning. Upon returning home the battery was still hot.

The thing that caused me to notice all this was the smell that a lead acid battery produces when it is charging. (Spent about 23 years on Submarines and believe me I know about lead acid batteries!)

I am wondering if anyone else has seen or been involved with a situation with your RVs and the actions taken to correct the situation.

The biggest thing that I find strange is that one battery is cool and the other is hot to the touch.

Thanks in advance for all your input!

Geff

I am not a battery expert but, if it is getting hot, I would be removing it from the system. I would then take it to a facility that has the capability to test the battery and give you a report on its condition.

[mhs4771]

Just from your discription, something isn't connected right with those batteries. The two batteries should be connected Positive to Positive and Negative to Negative. There should be a two black cables off the negative term one to chassis ground of the RW the other to the negative term of the Inverter. Then two Red cables coming of the Positive term (on the opposite battery from where the ground cable is connected) and one goes to the Battery Disconnect switch the other to the Positive term of the Inverter. The only other connections to the battery would be the starter for the Generator is equiped.
If you want more info, I can be contacted at 585-752-4705, I've added two additional batteries to our MB to give us extended run time for the fridge when not connected to the TV or Shore power.

[Shane Wood]

Originally Posted by deepunderh2o

One of my 2 batteries in my 2016 39MB is extremely hot. It boiled off about 1/2 gallon of water. The second battery is cool to the touch. The battery that is hot is the one that goes through the disconnect switch to the 12+ DC bus. The other battery that is cool has the lines going to the DC to AC converter to provide power to the residential refrigerator.

I have the Magnum Energy system panel. It was in float mod, charge rate was set to 100% charge (I have since changed it to 10%). I have also changed the charger from float to Stby. Voltage reading at the start has been 13.5 volts (Since adding water has dropped to 12.5) and remained at 13.5 volts even after putting the charger in Stby at about 0300 this morning. Upon returning home the battery was still hot.

The thing that caused me to notice all this was the smell that a lead acid battery produces when it is charging. (Spent about 23 years on Submarines and believe me I know about lead acid batteries!)

I am wondering if anyone else has seen or been involved with a situation with your RVs and the actions taken to correct the situation.

The biggest thing that I find strange is that one battery is cool and the other is hot to the touch.

Thanks in advance for all your input!

Geff

I had the same problem the no name no markings on the 2 12v batterys that came with the trailer 1 got hot and was boiling the other was fine. After 1 month of owning the new trailer. I replaced the with 2 new AGM interstates and have had no problem in the last year

[Tomkidder]

I was just talking with my Dad about this very thing a few days ago. I did not realize that if batteries are to be linked together in series they must be sister batteries..... By sister batteries mean they must be from the same lot number and as near to the same serial as the other. Of course I asked why??????? He told me that the internal resistance must be exactly the same and the only way to get that is if the batteries were made on the same machine. This is more important with AGM batteries vs lead acid batteries. If the batteries are in parallel than it makes no difference. How ever as most of you know, you can't mix lead acid and AGM batteries. You have to pick one or the other.

[deepunderh2o]

So after adding about 1/2 a gallon of water as mentioned earlier the temperature dropped in the hot battery. It has taken about 8 hours for the temperature to drop to the same as the other battery. Charger is still in Stby. I wanted to see how the "system" responded after adding the water.

Voltage dropped from the 13.5 range to 11.9. I will start the charger later today and see what happens.

The system has been function in this configuration for over a month now so I do not think that it is a wiring or configuration problem. That would have been evident much earlier.

My conclusion is that the charger was significantly over charging the batteries and as a result evaporated the water out of the batteries. Once the acid got concentrated too much it started causing the problems I have encountered.

[Tomkidder]

If you isolated the batteries what is the charger output as far as volts. Also look at the charger. Is it the 3-4 stage smart charger?

[deepunderh2o]

That is the next steps. Unfortunately the method used by Redwood to store dual batteries is shall I say less then forward thinking? They utilize the two separate single battery containers and simply punch holes in the cover. So about the only way to do any troubleshooting / work on them is to disconnect it as you go.

I am going to purchase a compartment that will properly house a set of dual batteries and provide access to the connections without have to disconnect everything.

Tom - thanks for your input!

[spindrift]

Originally Posted by deepunderh2o

My conclusion is that the charger was significantly over charging the batteries and as a result evaporated the water out of the batteries. Once the acid got concentrated too much it started causing the problems I have encountered.

If that's the case, then there's an issue with your charger. It should automatically go into float mode when the batteries are fully charged. If the charger continues to charge at full rate, it will definitely cause the water to boil off.

[piper guy]

Tomkidder - just need to mention, the batteries in the Redwood are a parallel hookup, not series. If you do a series hookup, really bad things will happen.

[Tomkidder]

Some people may want to series two 6volt golf cart batteries together to make 12 volts. Yes our 12 volt batteries are parallel wired. Deepunderh2o I agree with you on the battery boxes. I have been looking at having a rack placed in the same area.

[piper guy]

Good point ~ forgot about 6 volt setups.
MORyde makes a good battery tray. Going to put one in mine this spring.

[deepunderh2o]

Okay I have finally had a chance to dig into the situation. The front battery appears to have an internal cell short. As a result any effort to charge or utilize the batteries caused the battery overheat, gas, and boil of water in the battery. The second (Towards the back) battery appears to be okay. Water electrolyte level was a little low. I have reconnected that battery back into the electrical system. And started a charge on it.

I will be contacting Redwood for a set of replacement batteries next week.