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Cold cranking amp

  1. Jan 12, 2010 #1
    In my search for an answer I found a post regarding car batteries but it didnt offer me anything I was looking for. My question, or the a step toward the correct question is how exactly are cold cranking amps on any particular battery determined. At first I speculated it was the amount of or quality of lead used, however that opened more questions rather than answers. And, not to seek any sympathy but I sell batteries, not make them. My understanding of how they truly work and why is limited. Although it has been a fascinating journey finding information. If anyone can provide another step in the right direction or an answer I would be thrilled to hear it.
  2. jcsd
  3. Jan 12, 2010 #2


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    A battery that can supply greater current is one with less equivalent series resistance. To produce a battery that has very low series resistance, you need a very large electrode surface area, very large terminals, very ion-dense electrolytes, etc.

    - Warren
  4. Jan 13, 2010 #3
    A couple of more factoids from long ago -

    As battery plates became thinner, they could pack more in and get more cranking amps. This also made the plates more fragile and less tolerant to deep discharge.

    Later, they started adding calcium to the plates. I think this was to make them more robust while keeping the cranking amps up.

    I suspect the expression cold cranking amps came from a standardized test. The Society of Automotive Engineers has been good at standardizing anything that gets under the hood :)

    - Mike
  5. Jan 13, 2010 #4


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    Cold cranking amps are taken quite literally up here in Canada--the CCA at -20C or -40C had better be enough to turn your engine over and start your car!
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