Any two years reviews for Firefly batteries?

[Britishsea]

I purchased two G31s for a sail boat in the Pacific NorthWest.

I agree the batteries seems to charge faster than the AGM they replaced (Deka/ Penn 8D).

In my case, A Balmar regulator with a temp sensor kept the alternator in check.

As to the original post question re. general feed back, I had a battery Firefly G31 battery fail after 18 months. So if I was in the market today, I would buy with caution or make sure that the warranty terms are clear with the vendor.

[PNWSalmon]

Originally Posted by toolarts

The program for the MC 614 is actually on the Firefly website. I compared the built-in programs on the Balmar with the Firefly suggested program, and the one that comes closest is actually the Lithium Ion program on the MC-614. Since I am too lazy to put in an entirely new program using a magnetic screwdriver and a one-button menu, I use this one and it works pretty well--does not hit the full battery with 14.8 volts, which is what I care about
Cheers.

Hello, do you have a link to the Balmar program for the firefly? I’d love to have a copy of this but I can’t find it anywhere.

[RickG]

Attached is the charging profile I got from Bruce at https://oceanplanetenergy.com/.

Bruce has posted this in the past - https://www.cruisersforum.com/forums...lt-162539.html

This charging profile works fine for us with a Balmar 614 and a 110amp Balmar alternator.

Cheers, RickG

[AMFE]

I have had three of them for my house bank for about two years. Happy so far. But I just started living on the boat full time so I don't have a lot of on the hook experience with them yet thanks to C19.

Originally Posted by a64pilot

Anyone using the L15+’s?

[FlyingScot]

Originally Posted by a64pilot

Anyone using the L15+’s?

I just upgraded to six of them. Had three and I can tell you that six is way better. More than twice as good. I've only had then hooked up for a few days. Now I can discharge 300 amp-hours overnight and not even bat an eye.

Only problem is that they are 43 kg each which makes it harder to install. The expected increased life cycle count is worth it.

[OneHullPaul]

Charger stacking is quite popular now. I have 2 x 100amp chargers stacked to charge my 550 Amp hour AGM bank. Jeff Cote from Pacific Yachts has a great YouTube video about it.

Originally Posted by mlydon

Folks,

I'm interested in going with these batteries - all sounds great - big question is - HOW are you putting 170 or 220 ah into them?

Top Battery chargers around seem to put out sub-100amps. Top of the line Victron multiplus 3000 puts out 120, supposedly.

Thanks,

Matt

[jkleins]

Originally Posted by OneHullPaul

Charger stacking is quite popular now. I have 2 x 100amp chargers stacked to charge my 550 Amp hour AGM bank. Jeff Cote from Pacific Yachts has a great YouTube video about it.

Agreed. I have two 100 amps as well. It is actually great at keeping my generator loaded up as well as I can turn one of them down if needed to keep the load just right while running water maker, etc. If you use the exact same kind of inverter charger (I use Magnum) you also have complete redundancy if one goes out.

Jim

[jbinbi]

So I am looking at going to the dark side and getting a trawler. The model I am looking at is not very available solar real estate friendly. The boat only comes with 280 Ah, and I am looking to upgrade. Given that the engines are running way more (boat oddly only has 2 80A hitachi for 2 x 220HP engines), I was looking for a way to bring the SOC up much more quickly. So if I put 4 Fireflys on for 440Ah, do I really get to discharge say to 100Ah and thereby get 300 useable AH? And what about bringing it back. If I run both those alternators for 4 hours, will I get these back close to 100%. Boat has a generator, but would rather not run that just to charge the batteries. I have read the Practical Sailor article, it did not give a resounding conclusion that Firefly's are that much better than regular AGMs.

I don't want to spend the money to go Lithium, I don't want to build something myself, so I would have to get an integrated system from Victron or Mastervolt, and that is big $ I think. Appreciate any comments.

[phantomracer]

Originally Posted by jbinbi

So I am looking at going to the dark side and getting a trawler. The model I am looking at is not very available solar real estate friendly. The boat only comes with 280 Ah, and I am looking to upgrade. Given that the engines are running way more (boat oddly only has 2 80A hitachi for 2 x 220HP engines), I was looking for a way to bring the SOC up much more quickly. So if I put 4 Fireflys on for 440Ah, do I really get to discharge say to 100Ah and thereby get 300 useable AH? And what about bringing it back. If I run both those alternators for 4 hours, will I get these back close to 100%. Boat has a generator, but would rather not run that just to charge the batteries. I have read the Practical Sailor article, it did not give a resounding conclusion that Firefly's are that much better than regular AGMs.

I don't want to spend the money to go Lithium, I don't want to build something myself, so I would have to get an integrated system from Victron or Mastervolt, and that is big $ I think. Appreciate any comments.

PS pretty much said, IIRC, there is not enough history on them to make a recommendation.

I have been beating my fireflies badly for the past few years (into my 5th season). Regularly discharge 50+%. ALWAYS put the boat away with a PSOC state. Only now do I see any signs of slight performance loss. I also have not done a restorative charge (which firefly recommends). I will do that when the boat gets out of the water this fall. STILL, the performance is still better than the far more expensive Rolls wet cells, which I easily destroyed regularly. I am expecting to recover some, or most,of the performance loss of the firefly batteries during the restorative charge this winter

The firefly seem to accept more power faster than FLA. They are pretty much a swap in for FLA, unlike lithium.

But I will let the professionals answer. Just wanted to give some anecdotal comments.

[a64pilot]

Originally Posted by phantomracer

PS pretty much said, IIRC, there is not enough history on them to make a recommendation.

I have been beating my fireflies badly for the past few years (into my 5th season). Regularly discharge 50+%. ALWAYS put the boat away with a PSOC state. Only now do I see any signs of slight performance loss. I also have not done a restorative charge (which firefly recommends). I will do that when the boat gets out of the water this fall. STILL, the performance is still better than the far more expensive Rolls wet cells, which I easily destroyed regularly. I am expecting to recover some, or most,of the performance loss of the firefly batteries during the restorative charge this winter

The firefly seem to accept more power faster than FLA. They are pretty much a swap in for FLA, unlike lithium.

But I will let the professionals answer. Just wanted to give some anecdotal comments.

I’m familiar with what you were doing to batteries reference the fuel cell etc.
It’s going interesting to see how your restoration charge (s) work, I believe it’s at least two full complete discharged to 10.5V, then a high amp full recharge and a 24hr float, followed by another cycle.


In answer to the above question of how deep can you discharge them, yes you can do what you desire, but it’s going to significantly reduce their cycle life.
I believe the claimed cycle life to be nonsense myself but if you look the reduction in cycle life from 30% discharge to 80% discharge is roughly a factor of ten. So in other words each discharge to 20% SOC is reducing the life ten times as fast as a discharge to 70% SOC

I suck at math, so I included a screen shot of the data sheet for a G31, draw your on conclusions.

[jbinbi]

So A64, if what you say is true, why pay the premium for carbon foam? If you only get 1000 cycles by going to 80% DOD, what # do you get with regular FLA? If it is 100, then these are worth it. If it 900, then no.

I have read other reports that say you can bring your regular FLAs down to 25% SOC , you just give up cycles. But FLA are cheap, so big deal. Is this correct?

[phantomracer]

Originally Posted by jbinbi

So A64, if what you say is true, why pay the premium for carbon foam? If you only get 1000 cycles by going to 80% DOD, what # do you get with regular FLA? If it is 100, then these are worth it. If it 900, then no.

I have read other reports that say you can bring your regular FLAs down to 25% SOC , you just give up cycles. But FLA are cheap, so big deal. Is this correct?

to me, the biggest draw to the carbon foam is no problem with being left in a partial state of charge. Rarely do sailboats run the engine long enough to get the batteries to a true 100% charge. Being left in a PSOC..regularly..ruins batteries. Been there. done that. got the tshirt!

On a power boat, it may not be as big of a deal as it is on a sailboat. FLA may be a good choice if you can regularly get the batteries to a true 100%.

[ranger58sb]

Originally Posted by jbinbi

So A64, if what you say is true, why pay the premium for carbon foam? If you only get 1000 cycles by going to 80% DOD, what # do you get with regular FLA? If it is 100, then these are worth it. If it 900, then no.

Maybe just compare Firefly's 1000 cycles to 80% DoD (if that's their spec?).... to others that spec 1000 cycles to 50% DoD. That math may help visualize some differences...

-Chris

[sailorboy1]

Originally Posted by phantomracer

to me, the biggest draw to the carbon foam is no problem with being left in a partial state of charge.

That's why I am going to put some in.

Based on my 4 years full time on the boat my use shouldn't draw the batteries less than 70%. The Firefly chart says that the batteries will last 9,000-13,500 cycles. Do I believe that? Hell no I don't believe that!!!

Trojan said my T105s would last 300 "cycles" and they only went less than 60% SOC twice and 50% SOC once and lasted 4 years. So that is really only 1 cycle far as what a "cycle" is suppose to be. So this "cycle" thing is just lab use hocus pocus.

If I divide 9,000 for the FF by 300 for the Trojans I get 30 times as long. Do I think my FFs are going to last 4 years x 30 = 120 years? Hell no. But if I get 10 years with less worry about PSOC conditions I will be happy.

[jbinbi]

OK. But didn't the PS mag article say that just like all other AGMs, the Fifefly's needed to be brought back to 100% or they too 'walk back' towards a lower value? Maybe they just need to have this done on occasion, like an equalization process? Or was I not understanding something?

If you can goto 70-80 DOD, and still get as many cycles as 'regular' batteries, then this is a win. This means a 400AH bank is really 25-30% bigger, meaning 1 less battery you are buying, maintaining, etc.