Originally Posted By: ram_man
Originally Posted By: JHZR2
There is nothing wrong with pulling the caps and adding water. "maintenance free" implies less offgassing and better recombination, but they will still lose water and adding some is good for life.
On the other hand, fast charging above a 0.3C rate will create kinetics that will prevent recombination (and thus guarantee loss of water), as well as a high enough voltage to ensure electrolysis. 15.5V, depending upon the temperature is too high for being careful and gentle with the battery. It will create damage and capacity fade, if not release of lead floc that will be lost permanently and reduce overall capacity.
We are covering batteries right now in class and I can tell you that you are misinformed. A 3 min quick charge test should yield a result of 15.5v or lower if it is higher it is sulfated.
Also you should never remove those caps! That's not there designed purpose.
I'm willing to believe the text book and the master technician who does teaches the class. The boom clearly states it. Those caps are for venting and shouldn't be tampered with. I'm not trying to be rude but when messing with something like a battery it is best to yield on the side of caution and to also be very informed before tampering with one. Just because your method can be done does not make it right safe or at all a good idea. It's the same thing when people hook up a battery and hook up positive first they may do it for years before they fry something. Just because it doesn't dry something everytime doesn't make it an acceptable method.
From Interstate:
http://www.batteries-faq.com/activekb/questions.php?questionid=6
Quote:
How do I maintain my battery?
Note:
Interstate’s automotive and commercial starting and Marine/RV batteries are considered Maintenance-Free products under normal operating conditions. However, in the event of an extreme overheat/overcharge situation, the batteries may need to be checked for water loss.
We recommend the following:
1. How to check the water level and add water:
If your battery has removable vent caps then they can be pried off with a flat-head screwdriver. Once removed, you will see individual vent wells. Look down into each individual cell to make sure that the water is covering the lead plates and is at the proper level. Add water to any cells that are low on water. Always use distilled water that is available from a supermarket to fill the battery in order to prevent chemicals from contaminating the battery.
2. How to determine the proper water level:
Ideally, the water level should be no higher than just below or to the bottom of the tubes (in a 12-volt battery there are 6 tubes) that go down into the battery. To avoid damage to the battery, make sure the fluid level never drops below the tops of the lead plates in each of the cells. Also, avoid adding too much water, which may result in acid overflow and damage around the battery.