Battery recommendation

GordonThree wrote:

Matt_Colie wrote:
It is not a good idea to put 12V batteries in parallel - ever.

What is the reasoning behind this? Many coach are setup this way from the factory, as are boats and even some automobiles (some light trucks with snow plows have two batteries in parallel)

Those that are setup for it have matched batteries. The caution was to not go buy a battery and wire it to the existing battery. If that were going to be the choice the recommendation would be to go buy two exact matching 12v batteries but in that case you would be better off just going with two 6v because you would gain more for nearly the same cost.

Matt_Colie wrote:
It is not a good idea to put 12V batteries in parallel - ever.

What is the reasoning behind this? Many coach are setup this way from the factory, as are boats and even some automobiles (some light trucks with snow plows have two batteries in parallel)

Thanks all for replies. Will not put the current battery and whatever I purchase together.
Maybe I will go for 2 6 v or even 4 6 volt.
Thanks
Still researching!

You need to know the total amp hours you're going to be pulling for those two days, then add to that about %50 and build a battery bank that can supply that much power. You don't want to deeply discharge even deep cycle batteries (deep cycles have a higher tolerance for discharge, but they can still be damaged if you drain them too far) so you need to know how much power you need to supply.

As previously stated, a bank of 6v deep cycles will provide many more amp hours than a 12v, and they typically have thicker plates, deeper cases, etc. which will translate to longer life.

If you would like to learn more about 12v systems, I recommend the book "Managing 12 Volts: How to Upgrade, Operate, and Troubleshoot 12 Volt Electrical Systems", or the website http://www.marxrv.com/12volt/12volt.htm

- Randy

Walker,

It is not a good idea to put 12V batteries in parallel - ever. The idea is even worse if those two are not identical in every possible consideration. Lead acid batteries just do not play well together.

If you want good DC power, get a pair of golf cart batteries (6V) in series. They will last longer and perform better.

Matt

We currently use a pair of 6 volt Interstate GC2 batteries from Samsclub and they have been providing good service over the last 4 camping seasons. Good idea to go with a couple of batteries instead of just one, but it is not wise to pair an old battery with a new battery for a number of reasons. It really boils down to total amphours (12 volt or 6 volt jars work equally well) and how to most effectively restore consumed amphours. We use our genny and onboard Iota IQ4 smart converter to quickly replenish our stored 12 volt power supply and can easily go a couple of days without recharging, but we use our genny anyway about an hour a day for other high current demands and rarely require further recharging. Performing an LED conversion a couple of seasons back greatly enhanced our ability to reduce recharging intervals via genny.