Battery CCA vs. ah-rating

[organic farmer]

Is there a relationship [formula] between a battery 'Cold Cranking Amps' and that same battery 'ah' rating in the context of the Solar-Power community?

I know the CCAs of my batteries, but I am not absolutely sure of the exact 'ah'.

A friend of mine was showing me a meter he has that measures the exact CCA on batteries. So I am wondering if I tested my batteries and got their exact CCA, if that could lead me to a real-world 'ah' rating. My charge-controller wants to know the ah rating of my battery-bank.


Thanks.

[Sunking]

Is there a relationship [formula] between a battery 'Cold Cranking Amps' and that same battery 'ah' rating in the context of the Solar-Power community?

I know the CCAs of my batteries, but I am not absolutely sure of the exact 'ah'

No relationship what so ever. Deep cycle batteries do not have Cranking Amps Specifications. Only Starting Batteries and Hybrids have CA ratings, Deep cycles do not.

CCA is the amount of current a 12 volt battery can deliver for 30 seconds, at 0 degrees. at 7.2 volts. It is telling you the internal resistance of the battery at 0 degrees. So if you have a battery with CCA, you are using the wrong battery type.

Now a Hybrid battery will have a RC = Reserve Capacity rating is loosely coupled to AH. RC is how many minutes a battery can supply @ 25 amps until discharged to 10.5 volts. For example if RC = 120 minutes one can conclude the battery capacity at the 2-hour discharge rate is 50 Amp Hours. That same battery at the 20 hour rate will be considerably higher up around 80 to 90 AH.