850cca flooded vs 750cca AGM?

[930.engineering]

My understanding is for the average driver, an AGM battery will last longer than non-AGM. For example, the AGM battery in my 2016 BMW is the original battery and it's still going (touch wood).

My Mini Cooper was built in July of 2012. It's factory AGM (70 Ah, 760 A CCA, Exide) is still fine. Yes, touch wood.

Very most vehicle's alternators will easily charge an AGM, approximately 14.5 V while driving. The only disadvantages: AGM are more expensive and they don't like excessive temperatures (engine bay). Minnesota is not New Mexico.
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[wavinwayne]

...AGM are more expensive and they don't like excessive temperatures (engine bay)...
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I assume that's why BMW puts the battery in the trunk where it stays nice and cool (comparatively).

 

[930.engineering]

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Exactly, yes and it also helps for weight distribution to some extent.
My Mini's battery is sitting in its own dedicated compartment below the
cowl, right in front of the windshield and seperated from its engine bay.