batteries --- again!

5 hrs driving would not sufficiently charge your batteries (if disharged after your overnight draw) to 80% modern alternators are designed to maintain vehicle consumption whilst driving and charging a discharged battery is secondary ,that is why most modern alternator field currents are controlled by computer.

What happens when the 2 x batteries 'equalize' ?

This will happen when the battery isolator connects the 2 x batteries in parallel

The voltage may then be probably ~12.2v or even less, the alternator regulator reads 12.2v (or less) as the battery voltage.

Does the Alternator then charge the 'battery' accordingly ?

Maîneÿ . . .

the ac delco batteries are calcium hybrids and to fully charge them above 80% at some time they are going to need more than 14 .7 volts to charge them. no vehicle charging system goes above 14.8 volts . to fully charge them with normal driving conditions ,assuming the under bonnet temps do not go over 75'c the time necessary will be aproximately 12- 15 hours. it takes roughly 24+ nours to fully charge them on a workshop floorand in most cases the voltage exceeds 15 volts.

Stuart,
under the conditions you have mentioned, this acdelco battery is obviously totally worthless and a complete waste of money when used to run a fridge?

You say this type of battery will never get the full charge from the vehicle alternator when traveling, so obviously it will not last and may even sulphate due to inadequate charging.

The acdelco battery mentioned is only a cranking battery anyway, so the original poster is looking for serious problems keeping it, as you have said he won't be able to recharge it fully from his vehicle anyway.

I wonder if the battery supplier has told him of the inevitable problems the poster will have keeping the acdelco battery charged by his vehicle?

Maîneÿ . . .

get used to the fact of all batteries becoming calcium hybrids due to manufacturing costs and durability, the deep cycle belkors are also calcium hybrids , for their stabilty over harsh terrains , they are cheaper than gel batteries . new technologies including mercury hybrids will need higher voltages to charge them, lead acid with deep well space will become a thing of the past

I've used 2 x Delkor DC27's (80ah Deep Cycle calcium batteries)
They lasted 6 years and I only replaced them for safety reasons before they gave any trouble.
I had no problems with them, but they were 6 years old.
I replaced them with 2 x AGM's, so used one of the Delkors as my Cranking battery.

Maîneÿ . . .

Stuart,
Can you please reply to my question asked above :-)
I'm sure it is important to the many guys with Calcium batteries

"What happens when the 2 x batteries 'equalize' ?
This will happen when the battery isolator connects the 2 x batteries in parallel
The voltage may then be probably ~12.2v or even less, the alternator regulator reads 12.2v (or less) as the battery voltage.
Does the Alternator then charge the 'battery' accordingly ? "

With thanks

Maîneÿ . . .

when the batteries reach equal voltage you say at 12.2 v , i presume when the vehicle is not running. float battery at fully charged with no draw shoukd be 12.6V. when equalised the vehicle is running and charging, the batteries will be charged equally at 13.8-14.2v ,the battery with the most internal resistance may get ,or may tend to overcharge, especially when the batteries are mis matched in size.

Stuart,
You say: "FLOAT battery at fully charged with no draw shoukd be 12.6v"
I would suggest 'float voltage' is way in excess of 12.6v and would be in the visinity of 13.6v, indicating a simple typo :-)

Maîneÿ . . .

you are right