Equalizing Batteries

[Adam Hicklin]

I've brought this up before and received some good info but I still haven't done it.  But I need to..I'll turn off all the 12V breakers.  Do I need to disconnect the chassis batteries?  Anything else before I hit the equalize button?

[Mike Groves]

Adam,

The only caution I've followed is to limit my energy use while doing this, and prior to doing it make sure all the batteries are topped up.  I have not disconnected the chassis batteries. 

Given this, the best time to do this in my opinion is overnight when you're parked/camping and have the shore power.  Obviously at home you can do it anytime.  But while camping and asleep its easy enough to turn things off.

I do wonder, however, why with 50amps you have to worry too much about turning stuff off as long as you're not using the AC and washer/dryer.

Mike

[Fred Brooks]

        Hi Adam,

    Traditionally the reason we would perform an"equalization charge" is to rejuvinate an older, tired wet cell batteries. The objective is to get the accumulated sulfate off the lead plates and back into solution to raise the specific gravity of the liquid inside the battery thus improving its amp hours back towards normal. The process is messy and creates a lot of gas.

     When I have done it, I always start around 10.00 pm and follow all the precautions. Towards the end of the end of charge cycle (6-8 hours) the voltage goes up around 15.5 to 16 volts and makes the batteries "boil". I always leave the compartment door open. 2- donot top off the cells because of the mess, 3- put an old towel over the batteries and dispose of properly tomorrow using rubber gloves. 4-put a small desk fan on a ladder to ventalate the area during the process. The following morning clean the batteries and compartment. then install distilled water back up to fill line.

     Hope this helps, Fred

[Steve Huber Co-Admin]

Adam,
You might want to check the specific gravity of the battery cells. Trojan recommends equalizing if there is more than a .015 difference between cells of a fully charged battery.
Steve

[Mike Groves]

        Hi Adam,

    Traditionally the reason we would perform an"equalization charge" is to rejuvinate an older, tired wet cell batteries. The objective is to get the accumulated sulfate off the lead plates and back into solution to raise the specific gravity of the liquid inside the battery thus improving its amp hours back towards normal. The process is messy and creates a lot of gas.

     When I have done it, I always start around 10.00 pm and follow all the precautions. Towards the end of the end of charge cycle (6-8 hours) the voltage goes up around 15.5 to 16 volts and makes the batteries "boil". I always leave the compartment door open. 2- donot top off the cells because of the mess, 3- put an old towel over the batteries and dispose of properly tomorrow using rubber gloves. 4-put a small desk fan on a ladder to ventalate the area during the process. The following morning clean the batteries and compartment. then install distilled water back up to fill line.

     Hope this helps, Fred

Fred,

I believe the manufacturer of my coach batteries, says do it every 3 months to keep the charges the same in all 6 batteries (or as nearly as possible), and it does also say to make sure the water level is where it should be since you are going to be boiling off the water, and not the chemical. 

Thanks,
Mike

[Adam Hicklin]

My Prosine manual doesn't say anything about the process.  I know they've never been done before and they're about 5 years old.  Still seem to be healthy for the most part.

Fred, will they actually boil over?  Should I leave the caps on or take them off?  I'm home getting ready for a trip so I thought I would turn all the 12 volt stuff off at the breaker, just to be safe.  Is that not necessary?  I'll keep the bay door open, set up a fan as you suggest along with your other suggestion.

Mike, do you notice any difference after an equalization?

[Edward Buker]

Adam,

Fred had a good description of what you are trying to achieve by sloughing off some of the sulfate from the plates and putting a bit more available acid back in solution. That being said, this is a messy process, that may gain a bit more capacity out of your battery bank. If you boondock, and your batteries are older, you may notice a small difference in capacity. If you mostly keep the coach plugged in and spend your time in campgrounds with shore power connected, it will probably make little to no difference because you do not need that small amount of extra capacity.

If you equalize, you will have some fluid vent out with the vigorous outgassing that should be neutralized with baking soda and water. The battery compartment should be washed down and cleaned before you uncap the cells and add distilled water if you find that is needed.

If you boondock then by all means consider this procedure, if not then I would for the most part skip the practice or do it very rarely. I probably average once in 5 years going through an equalization cycle given I rarely discharge my batteries very deeply so I expect to have minimal sulfating of the plates.

Later Ed

[Steven Hoffman]

Adam

The reason for turning off all the 12 volt stuff is as Fred said " Towards the end of the end of charge cycle (6-8 hours) the voltage goes up around 15.5 to 16 volts ".  This is getting to be pretty high voltage for 12 volt "stuff".  So to prevent any possible damage it is recommended to turn things off. 

[Mike Groves]

My Prosine manual doesn't say anything about the process.  I know they've never been done before and they're about 5 years old.  Still seem to be healthy for the most part.

Fred, will they actually boil over?  Should I leave the caps on or take them off?  I'm home getting ready for a trip so I thought I would turn all the 12 volt stuff off at the breaker, just to be safe.  Is that not necessary?  I'll keep the bay door open, set up a fan as you suggest along with your other suggestion.

Mike, do you notice any difference after an equalization?

Adam,

Sorry for the late reply.  I don't see any difference afterwards and I think that's the point.  Mine were new in August 2013, and I have been doing the equalization process sporadically, which reminds me, it time for another since I am hooked up.  So, my impression is its simply to make sure all batteries are healthy.  How would I know?  I guess if I tested each individually.  But typically, my testing is "real life", in as much as, do the batteries power the coach as I've been used to them powering the coach.  I know, for instance, that if I start the microwave using them, then it doesn't take long before I get an alarm on the prosine, but I can heat my instant hot water with them.

You don't have to remove the covers but make sure there is water covering the cells to the level required because the water will "boil off", then check afterwards, and top up.  It's not a very serious process UNLESS you've depleted the water and don't fill to the line prior to doing it.

Mike