Dual Batteries help to understand

[Moley]

I read that having separate style batteries like a wet cell and an agm style is no good cause the alt will charge the agm faster and the voltage regulator will either overcharge the agm while it's trying to top up the wet cell or it will just stop charging cause the agm is full. Which one is true and is that going to change if I have two agm style batteries that are different size. I mean if I had a kinetik hc800 in the back and a kinetik hc1400 in the front the same thing would happen. Like I mean the small one would charge first. I need to know what is going on with dual batteries and the best thing I should do.

[crunkjuice1]

[Moley]

I have done mad research but I need more. I need a forum to go to that has a bunch of experts on a panel answering questions. No one can ever answer the really technical questions.

Edited December 28, 2010 by Moley

[TeamHT]

Or instead of trying be smart about it, you could actually be SMART about it. The question was placed in the general audio section, so I highly doubt you're going to a panel of judges to answer your every whim.

A forum is just that...a forum. And although there is a wealth of knowledge, just looking around is not going to be enough.

Even i dont know a very plausible answer to your question off the top of my head, and would think a question like this would better be answered by a person specializing in charging systems and batteries.

Hey.

Why not email someone like nate from XS?

[TeamHT]

But if i had to guess...the charging requirements of the two batteries are very different. The charge, acceptance, and float of these two would almost require two sepearate charging systems. A charger optimized for the wet cell will be too high voltage for the AGM shortening its life, and one optimized for the AGM won't keep the wet cell up to optimum charge, shortening it''s life. Which is pretty close to what it looks like you posted.

Why mix anyways?

[Moley]

Or instead of trying be smart about it, you could actually be SMART about it. The question was placed in the general audio section, so I highly doubt you're going to a panel of judges to answer your every whim.

A forum is just that...a forum. And although there is a wealth of knowledge, just looking around is not going to be enough.

Even i dont know a very plausible answer to your question off the top of my head, and would think a question like this would better be answered by a person specializing in charging systems and batteries.

Hey.

Why not email someone like nate from XS?

The only reason I posted that question in Genereal Audio was because under it it says "Have question Ask here." I didn't want to come off as "smart." The remark about a panel of experts was a facetious one and not to be taken literally. Sorry.

Edited December 28, 2010 by Moley

[Moley]

But if i had to guess...the charging requirements of the two batteries are very different. The charge, acceptance, and float of these two would almost require two sepearate charging systems. A charger optimized for the wet cell will be too high voltage for the AGM shortening its life, and one optimized for the AGM won't keep the wet cell up to optimum charge, shortening it''s life. Which is pretty close to what it looks like you posted.

Why mix anyways?

It is truely difficult for me to understand what is going on with the charging of dual batteries. Please understand my concern. I have a 2010 genesis coupe and I would ideally like to have two agm style batteries. One under the hood and one in the trunk. The problem is that the Kinetik HC1400 and the Shuriken BT60 ( smallest recommended )won't fit under my hood without mods ( cutting ). So I am forced to keep my stock battery and get another one for the trunk. I am concerned about the " mixing " of these batteries and how that will affect everything overall.

[thecityxignites]

xs power might have a battery that will fit under the hood without cutting shit. talk to nate.

[Boon]

Different sizes of the same batteries is fine. Parallel batteries of the same type work essentially like 1 large cell so the voltage will rise the same for all of them. Components in parallel V1=V2=V3=Vx - Likewise when you are discharging them the small one will not go flat first, they will discharge equally.

The issue with mixing AGM and wet cell batteries is the float voltage. AGMs float quite a lot higher than wet cells normally so there will be a charge imbalance between the batteries. Since everything will tend towards equilibrium the batteries will constantly try to balance themselves out which eventually results in everything being flat.

In the real world however... it doesn't matter. I've run stock batteries up front (CBF modding for bigger ones) with AGM battery banks in the back and never had any issues with either charging or the car going flat. That said it was a daily-ish driver so it was getting topped up regularly. If it didn't get driven for a couple of weeks it would be a little hard to start but 3 batteries, even if they're a little tired, should be able to turn over anything short of a V8.

[Moley]

xs power might have a battery that will fit under the hood without cutting shit. talk to nate.

Unfortunately the 3 magor car audio agm style battery companies ( Kinetik, Shuriken and XS ) don't make one that will fit in my car. They are all too tall I could use the kinetik HC800 size but IDK about that.