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It turns out this is a different method of rating deep cycle automotive batteries and has a different test standard than CCA, and may not be able to be calculated or converted back-and-forth because the test method and temperatures are different. So I did some reading to get some battery-specific grass-roots easy to understand basic info that I am probably misunderstanding and misinterpreting, however the gent this afternoon tried to point me in the right direction.

(you can checkout these citations later to be sure).

http://www.windpowerunlimited.com/batteries/Amp_Hours.htm

http://www.exploroz.com/Forum/Topic/49872/Questions_about_Amp_Hours.aspx

Generally the citations say:

"Cranking batteries are rated at CCA (Cold Cranking Amps), the power it can provide instantaneously and for a very short period. Deep Cycle batteries are rated at AH (Amp Hours). [Warrior battery is 12ah]

The

**20 hour**rate is an industry 'standard' for deep cycle batteries, but is not used by all manufacturers. Some quote at different rates, while some quote at multiple rates or show a graph. What it means is that if the battery is run down from fully charged to flat over a 20 hour period, it will provide "x" Amps of power. [Warrior battery is 10-hour1.2 amps - not sure how to relate this]

The faster a battery is discharged, the less total power it will provide. So it is always worth checking the standard used for the specifications.

**A 100AH battery quoted at the 10 hour rate will supply more power than a battery quoted at the 20 hour rate**and a lot more than one quoted at the 100 hour rate."

"An amp-hour is one amp for one hour, or 10 amps for 1/10 of an hour and so forth. It is amps X hours. If you have something that pulls 20 amps, and you use it for 20 minutes, then the amp-hours used would be 20 (amps) X .333 (hours), or 6.67 AH. "

--------- There's a chart to determine the linear power consumption factor which in this case is 88% so 12ah x0.88 = 10.56ah.

But for this example it ignores linear power consumption.Its a 12ah battery, so it can provide 12 amps for one hour, or 120 amps for 1/10th hour (6 minutes). Or 10.56ah = 10.56a for an hour, or 105a for 6 minutes.

The Warrior starter motor is .9kW or 900 watts. Forgetting about temperatures and variables, just in theory,900w / 12v = the starter draws 75 amps. A 12 ah battery can provide 75 amps for about 9.6 minutes, is that right?

Checking the math, 12ah = 12 amps for one hour (60 minutes). 9.6-minutes is 0.16 hours.75a x 0.16hours = 12ah. Again the battery can provide 75 amps for 9.6 minutes, assuming a full charge (ignoring temperature and other variables).

I recognize there are other factors I'm too ignorant to know about - I'm not a battery engineer just a biker! From the material on the net there doesn't appear to be a direct conversion from 10-hour-amperage to cold-cranking-amperage.

Does anyone know of some secret conversion factor we can use to convert10.56ah to CCA?