Calcium Batteries?

This might be of interest:

Is there a fitment guide that recommends the intended battery for your car?

(Ha - an answer! . . . good to see this group still works)

At the VWAudio forum, I'm told that the part number is 000 915 105 DG, but I'm not clear if that is a calcium battery or not.

Technically it is a lead-acid batter and calcium is a marketing tool.

Personally, I think you're overthinking this and it should be fine. Calcium versions are said to accept a higher charging voltage without gassing.

They will still charge at 14.4V, just like any other lead-acid battery.

You sure? I've seen a lot about them needing 14.8. Honest John says: "Despite the name, a 'calcium' battery is still a lead acid battery - it just means antimony in the plates of the battery has been replaced by calcium. This means it's more resistant to corrosion but it does require a higher charge voltage than conventional batteries. "

and from

In practical terms, the interchangeability of lead-acid and lead-calcium batteries depends on the specific application and the requirements of the system. In some cases, lead-calcium batteries may be a suitable replacement for lead-acid batteries, while in other cases, they may not be.

One important consideration is the voltage and capacity of the battery. Lead-calcium batteries typically have a slightly higher voltage than lead-acid batteries, which can affect the performance of the system if it is not designed to handle the higher voltage."

Yes there is little doubt that I'm overthinking it but I like to get to the bottom of things.

The basic chemistry is lead acid. The calcium battery will accept a higher charge voltage with less outgassing. I'm not convinced its a pre-requisite for such a battery to accept a charge to need the higher charging voltage.

While I also see many articles that say a charging voltage should be within 14.4-14.8V I've never seen any graphs of charge and voltage over time. Hell, the float charge voltage for a lead acid is 13.6 to 13.8V and it will become fully charged at that float charging voltage, albeit eventually. It's all about time and voltage to get to a known state of charge. Furthermore some articles say the terminals won't corrode as much which is BS. Other BS terms I have seen is "recombination process".

The real advantage of a calcium battery is it is resistant to corrosion; it has no excessive gassing, less water usage, and reduced self-discharge. And that last point that will be overwhelmed by the discharge from the car's electronics anyway.

YMMV

I remember, years ago, buying a gel battery for my motorbike (I thought it would be safer if I fell off). I was surprised to find it was just like any other vehicle battery.

Almost, a significant difference is it wouldn't leak acid if inverted.