wet cell vs agm in multiple battery set-ups

[RSDXzec 10+ year member]

I will be getting a new car battery soon and I'm unsure whether to go wet cell or agm. The determining factor here is I only plan to use this car for another 2 years so I'll move the battery to a new one and I plan on building a higher power system when I do so. Therefore I'll need more battery power so I'll need multiple batteries. Now I know wet cell batteries need to have exactly the same properties in order to function well in multiple setups so they need to be the same brand/model, it's also bad news to mix AGM and wet cell together, but would I be able to buy a 100Ah AGM battery now and pair it up with another 100Ah AGM battery in the future even if it's a different brand? Or what specs would need to match in order to pair up different AGM batteries?

I know when mixing wet cell batteries that they generally have different internal impedances which cause one to be drained more than the other, afaik AGM batts have a much lower internal impedance but do all AGM batts have an internal resistance close enough to one another to be run in parallel successfully?

Feel free to correct any mistakes I made in what I've said if my basic knowledge is wrong.

I'm asking because I doubt I'll be able to find exactly the same battery that I get now in another 2-3 years time and I'm pretty sure wet cell batteries can't be mixed but if AGM can be mixed regardless of brand then I'm sold on the AGMs. It will be used under the hood as a starter + aux battery.

I've read on the internet AGM batteries have a lower charging voltage than wet cell batts, which works out for me because my alt charges at around 13.8V +/- 0.2V, so will a regular household car battery charger work on an AGM battery?

My alternator is 85Amps if it matters at all for any of these questions.

This is the AGM battery I've currently got my eye on >> (Keep in mind I'm limited to the Australian Market here)

SSB HVT AGM DEEP CYCLE 12V 100AH BATTERY N70ZZ DRY CELL

http://www.allpurposebatteries.com.au/product_info.php?cPath=1&products_id=146

My current starter battery only has 330CCA and starts the car up great so with 780CCA there I should be fine imo.

Cheers.

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[RSDXzec 10+ year member]

anyone got any info/opinions?

 

[goingdef 10+ year member]

my only piece of advice is not to run wetcells in your car, and for ca they just don't work well I like my optima yellowtop just fine but it's also not good to add a new battery to an old one, so you can trade in the optima in a couple years for a new one when you buy another.

 

[RSDXzec 10+ year member]

my only piece of advice is not to run wetcells in your car, and for ca they just don't work well I like my optima yellowtop just fine but it's also not good to add a new battery to an old one, so you can trade in the optima in a couple years for a new one when you buy another.

yeah i know about the gasses released, finally decided i'd go with AGM inside the car so I can go for as big a batt as i want. This is bigger, more powerfull (in CCA) and cheaper

ALL PURPOSE BATTERIES PTY LTD

I know it wouldn't be recommended to add a new battery with an old one, but I'd like to know if it would work with AGM any better than it would for wet batts.

 

[goingdef 10+ year member]

yeah i know about the gasses released, finally decided i'd go with AGM inside the car so I can go for as big a batt as i want. This is bigger, more powerfull (in CCA) and cheaper ALL PURPOSE BATTERIES PTY LTD

I know it wouldn't be recommended to add a new battery with an old one, but I'd like to know if it would work with AGM any better than it would for wet batts.

I don't see why it wouldn't be compatible with all other agm batteries, and with adding to an existing system if the batteries rest a the same voltage it should be fine.