New AGM batteries from Trojan

[ranger58sb]

Only just now saw a note about these elsewhere. Looks like characteristics similar to what Firefly advertised:

Trojan Battery | Trojan AES AGM Batteries

The AES is designed to handle extreme deep cycle (up to 100% DoD), partial charging, or challenging environments. Available in 6V, 8V and 12-volt models, Trojan AES helps you avoid frequent battery replacements.

www.trojanbattery.com

Premium competition for Odyssey (now including Northstar) and Lifeline (and maybe Full River?).

I haven't been able to find what "AES" stands for; probably overlooking something...

-Chris

 

[rslifkin]

They're definitely making similar claims to Firefly, so I'm curious how they perform. Interestingly, they look to have fairly low capacity for their sizes (355 AH at 20 hours for an L16 is rather low, as is 175 AH for a J185 form factor). I'm not sure if the lower capacity is just the tech leading to lower density, or if they've just kept the design conservative. They are also a few pounds lighter than many in those sizes to go along with the lower capacity.

 

[DDW]

Even if they meet the claimed specs, they seem like a poor economic choice compared to lithium. About 70% of the price, and about 1/4 the life. I'd like to see them independently tested, but if some constraint made you stick with AGM they might be worth a try.

 

[ranger58sb]

but if some constraint made you stick with AGM they might be worth a try.

Example: In our case, the boat builder dual-purposed both of our start banks, so each runs approx. half of the house. And then I dual-purposed our thruster bank, so it now services the inverter we installed.

So the starting and thruster loads are the constraints we're faced with. (I didn't review Trojan specs about CCA and current limits; just assuming those are probably OK.)

Less hassle in our case -- and in the short term -- to buy new batteries occasionally than it would be to totally redesign our physical and logical battery architecture.

-Chris

 

[DavidM]

They sure are expensive. Amazon has a G31 for $500. That is 2-3 times more than a no name AGM.

If I wanted the 100% depth of discharge capability on my MH’s batteries, it would be cheaper to install 100 Ah LiTime li batteries, upgrade the converter to be compatible and (if testing indicated it was necessary) upgrade the BIM to a Li BIM225 to protect the alternator.

$&#%, I keep forgetting that this is Trawler Forum and not an RV forum. Forget the BIM and the converter upgrade, but the battery charger may need upgrading to be compatible and you may need a DC to DC charger to protect the alternator from overheating.

David

 

[rslifkin]

Example: In our case, the boat builder dual-purposed both of our start banks, so each runs approx. half of the house. And then I dual-purposed our thruster bank, so it now services the inverter we installed.

So the starting and thruster loads are the constraints we're faced with. (I didn't review Trojan specs about CCA and current limits; just assuming those are probably OK.)

Less hassle in our case -- and in the short term -- to buy new batteries occasionally than it would be to totally redesign our physical and logical battery architecture.

-Chris

My boat was done that way from the factory, but it turned out to be pretty easy to split off a proper house bank. It involved some new wiring related to house power distribution and charging, then just tracing and relocating the 2 feeds to the DC panel so they fed from the house bank instead of the start batteries. In general it turned out to be surprisingly simple.

 

[Bacchus]

Trojan advises 80% DOD will not harm their std AGMs so seems like a high premium for the addnl capacity?

 

[DDW]

Well I'd say the real upgrade is the ability to run at PSC without consequences. That is really the weak point of AGMs.