Small 'light weight' absorbent glass mat (agm) batteries

[sa_lux]

G'Day Guys

I would like to buy 2-3 small 'light weight' absorbent glass mat (agm) batteries.

Mainly because it is so hard to get a large AGM into the 2nd batt. setup under the bonnet.

I'm hoping to mount 1 in engine bay & 2 x AGMs in tub.

Anyone bought a smaller AGM & like to share experience ?

[creaky]

Define 'smaller'

[sa_lux]

G'Day Creaky

Have you installed a 2nd bat. under bonnet in your rig ?

AGM battery -> Std. 120AH Big Battery

Define 'smaller'

I would like half the height & weight of these, which are

Weight: 32.5kg
Dimensions: (LxWxH) 329 x 173 x 209mm

So

Weight: 10-15 Kg
Dimensions: Half the width 60-80mm the height & length I'm not so concerned about as I'm thinking of installing inside the panel in the tub behind the wheel arches.

I have installed lithum batteries already, but lots of work finding 2nd hand as new ones are approx. $10 each.

[creaky]

Yes, I have a Deka Seamate AGM under bonnet 92AH nominally in N70 size. I also have a 120AH beast in a 'portable' box at work that I can throw into the tub if I feel the need (which I haven't yet).

You'd be doing very well to fit the 120AH 'big battery' you linked to under bonnet. A lot of the smaller, say 60AH down, AGMs are not designed for life in a hot engine bay but would be fine for a tub mount in a box of some kind.

If you are planning to charge all of these batteries using one DC-DC charger then make sure they are all the same type and, preferably, the same brand/model and capacity.

Personally, I would suggest an N70 under the bonnet and whatever extra you want in a single battery in the tub.

$10 lithium battery ? What size is that, what charger do you use and for what purpose ?

[Steveyb]

What creaky said mate, IMHO agm's aren't a good choice for an engine bay.

[MarkTGood]

I read that agm batteries are unsuitable for installation
under the bonnet but seeing as I had a spare 85AH left over from a job so I fitted it anyway. It lasted about 4 weeks.

It wasn't an automotive battery but it's since been replaced with a Century N70 wet cell battery

Mark

[sa_lux]

G'Day Creaky

See below

Yes, I have a Deka Seamate AGM under bonnet 92AH nominally in N70 size.

How long have you had the AGM under the bonnet ?

You'd be doing very well to fit the 120AH 'big battery' you linked to under bonnet.

I had to move the orig. batt. forward & the AGM was only in for 48 hrs

I was hoping to buy a cheaper AGM & try it in engine bay to see how long it was performing the same as the other 2 which will be in the tub!!!

If you are planning to charge all of these batteries using one DC-DC charger then make sure they are all the same type and, preferably, the same brand/model and capacity.

Charging is not something I have given a lot of thought to as yet, still working on the physical issues.

Yes I was going to buy 3 identical AGM Bats.

$10 lithium battery ? What size is that, what charger do you use and for what purpose ?

They are the same size as in the Tesla batt. bank & not for install into engine bay. They would be ideal as they are very light to install behind wheel arch in the tub.

I have been working on 2 x proj. in parallel replacing a 12v lead acid cranking batt. with

- Tesla batts.
- Ultracapacitors

Getting the 'consumables' for each of these is very difficult in Oz, the Tesla batts. are $10+/each in Oz, I can buy for $1-2 in .cn but the amp hours they are quoting is nothing like the actual reading of the batts. So I have wasted a lot of time on this.

[sa_lux]

G'Day Steve

What creaky said mate, IMHO agm's aren't a good choice for an engine bay.

Thanks for the heads up mate.

As I get the impression you are an auto sparky I have actually been thinking of IMing you & asking you for some advise - I dont want to embarass myself with my lack of knowledge

[Steveyb]

G'Day Steve

What creaky said mate, IMHO agm's aren't a good choice for an engine bay.

Thanks for the heads up mate.

As I get the impression you are an auto sparky I have actually been thinking of IMing you & asking you for some advise - I dont want to embarass myself with my lack of knowledge

Just a normal sparky mate, I work on electric drive haul trucks so still have to do a bit of auto sparky work, welcome to msg if I can help I will

Cheers mate.

[sa_lux]

G'Day Steveyb

I know this is an old thread & that you are not a auto sparky, but

Do you know the

Cranking voltage & amps required for a diesel '12 ?

I have been having issues with the ultra capacitors & I just realised I have been going on US figures for a tacoma

Thanks

[gorilla5150]

It’s interesting reading this thread and the replies about not putting an AGM under bonnet. I’ve had a 110 watt AGM under my N70 bonnet in the 2nd battery bay on an ARB battery tray for just over 5 years and it’s just given up the ghost. It’s worked brilliantly all this time. Next battery will be a lithium under bonnet.