pianotuna wrote:
Hi,
Better tell Rolls/Surrette that their batteries which do list CCA are not truly deep cycle.
theoldwizard1 wrote:
The real issue is cost and availability of TRUE deep discharge 12V batteries. "Dual purpose"/"marine" batteries are a compromise. Any battery that advertises Cold Cranking Amps (CCA) or Marine Cranking Amps (MCA) is NOT a true deep discharge battery. These will have a short life when used in an RV.
All batteries have CCA and MCA ratings. They just are not typically advertised for true deep cycle batteries. These ratings are typically associated with starting an engine where you need lots of amps but only for a few seconds.
It's common in boating applications where you are staring a little 20-30hp sailboat engine to use the deep cycle house battery bank to also start the engine as the MCA rating needed is very low compared to a pickup with a 300hp diesel.
It does not harm to use them this way but if you tried to replace your pickup batteries with true deep cycle, you might need 4-6 times the batteries to get enough CCA. This would be very inefficient if you don't need a lot of amp-hr (plus where are you going to install 6 batteries).
