Originally Posted by Janjim
Thanks for the input.
3 and 1/2 years old. I've only had it 6mos. And frankly there has been these or similar issues since I purchased. I can't complain I did get a great deal, but they were charging it at the time.
Where would one find the main battery bank charging cables?
Banks of batteries in RV's are usually wired to provide 12 volt output. 12 volt batteries are wired in "parallel" to produce a larger capacity battery bank. Each battery positive terminal is wired to its neighbor. Each negative terminal is also wired to its neighbor. One cable from battery positive goes to house circuits. Another cable goes from battery negative to house circuits. The "one" cables are the main battery wires used for charging and discharging.
6 volt batteries are wired in pairs in "series" to provide 12 volt pairs. One positive is wired to its pair negative. That produces 12 volts from one battery positive to the other battery negative. The 12 volt pairs are then wired the same as the 12 volt batteries. One cable from 12 volt positive goes to house circuits. Another cable goes from 12 volt negative to house circuits.
Replacing all the batteries in the battery bank will get best performance and longest life. In theory any individual 12 volt battery or any pair of 6 volt batteries can be replaced with one of the same chemistry.
However, if the whole battery bank has been abused or is worn out and one or two have failed, then the others are likely near failure as well. This is a good reason to replace them all.
Drawing flooded cells down flat causes damage to the lead plates and support structure. Flakes of lead can bridge the small space between plates or accumulate in the bottom to cause short circuits between plates. Large pieces of plates can become detached and greatly decrease capacity. This may be what happened to one or two of your batteries.
Properly maintained lead acid batteries get about 300 to 400 full discharge cycles. Full time dry camping where substantial charge is performed every day can last for 2 to 5 years. Periodic vacation use or occasional weekend use can last for 10 years or more.
The key is proper maintenance. Always store lead acid batteries fully charged. That is 14 to 18 hours of charging. Ignore voltage based battery monitors. They are only accurate when batteries are sitting without charge or discharge for a few hours. 14 hours is necessary to clean the sulfate crystals off the plates. Leaving it there causes the crystals to become permanently attached. For full timing, a full 14 to 18 hour charge is required periodically.
Always maintain water level, especially after charging. Charging consumes water. Refill with distilled water only. Salts and contaminates interfere with the chemistry.
Occasionally "condition" flooded cell batteries to "stir" the electrolyte. Electrolyte tends to stratify after a while. Flooded cell batteries are said to "boil". Actually they are emitting hydrogen and oxygen. The "boiling" stirs the electrolyte. Do not
do this with AGM batteries. They do not need stirring.
Periodically clean acid spray deposits off battery cases, terminals, and cables. The spray is deposited when flooded cell batteries are charged. High voltage (15.0 volts) overcharging or fast (14.5 volts) charging causes both more acid spray and consumes more water. This is sometimes done to "condition" or restore capacity lost due to sulfate accumulation.
I wish you good luck and happy trails ahead!