Firefly carbon foam batteries

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wwestman

Senior Member
Joined
Apr 20, 2015
Messages
395
Location
USA
Vessel Name
Excellent Adventure
Vessel Make
1995 Jefferson Ker Shine 45
Got an ad today (most of you probably got the same thing) for Firefly Carbon Foam batteries. These are new to me. Anyone know anything about them?
 
They pretty much give you lithium type performance without having to build a science project on your boat. A friend recently installed these batteries. The only downside, so far, is that the batteries should not be kept on a float charge. Your charger will have to recognize when the batteries are full and then stop charging. Once voltage drops to a preset level the batteries would again be charged to full level and then stopped. His magnum charger, unfortunately, is a couple years older than mine and does not have that functionality.
 
I'm likewise interested in them. The previous owner's battery setup is... puzzling. In the next few weeks we're going to tackle untangling what's there and how to best move forward.

What little I've read online seems to have good things to say about their price/performance. Sort of half-way between AGM and LiFePo4 price-wise but without the Lithium issues.
 
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These are similar to AGM batteries, except that they will tolerate long periods of partial state of charge which AGM will not. They are nothing like lithium in charge or discharge requirements and restrictions. You can float charge them just like AGM though the float voltage should be set lower (13.4V instead of 13.7).
 
I used them on my sailboat for a couple of years, and really appreciated the additional capacity they provided since they can be discharged quite a bit deeper than traditional flooded/AGM batteries. But it did require a separate charger with specific programming to ensure they were taken care of.

I had an issue with weight and space, though, and ended up doing a "science project" as another poster described LiFePO4/Lithium installs. It worked well too, but it was not cheap.

I think will be doing LiFePO4 on the new boat as well, although a slightly cheaper solution, as it gets me 200-300 amp hours more than Firefly's could with the space available, and a lot of other benefits.
 
That's my debate now, Lithium or what? I think my Mastervolt Mass Combi is capable, and I'm looking to add whatever instrumentation is necessary to avoid wrecking things.

The previous owners had made what can only kindly be called a 'sarcophagus' for the main battery bank. I kid you not, it's literally a coffin-size box on the outboard port side of the engine room. No idea what's in there, but we noted there's a bit of a list to the port that's no doubt coming from that massive box of lead. There's even fans to/from it (you can just make out the black vent hose). I've never even seen inside the box.

I joked with my guy earlier this week it's only by random chance that nothing went wrong with the existing battery setup last season.

I've already committed to the idea that it's cheaper to rip-and-replace than it is to debug WTF is going on. I mean, why burn labor hours figuring out what's screwy when it may very well result in installing a whole new setup anyway? Probably not without spending more, of course, but at least it's not dozens of hours wasted figuring out "oh, it's crap, chuck it".
 

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..The previous owners had made what can only kindly be called a 'sarcophagus' for the main battery bank. I kid you not, it's literally a coffin-size box on the outboard port side of the engine room. No idea what's in there, but we noted there's a bit of a list to the port that's no doubt coming from that massive box of lead. There's even fans to/from it (you can just make out the black vent hose). I've never even seen inside the box.

I joked with my guy earlier this week it's only by random chance that nothing went wrong with the existing battery setup last season.
Good grief! You really need to unscrew the lid and look inside. Didn`t the surveyor peek inside either?
 
Good grief! You really need to unscrew the lid and look inside. Didn`t the surveyor peek inside either?

They did look in there during the survey and nothing problematic was found.

It was one of those 'get around to it' things that didn't happen. There just wasn't a whole afternoon free to contort myself all the way back in there, only to discover a lot more of 'what the heck?' questions. It wasn't acting up, so I ignored it.

So, yeah, 'good grief' is right.

My boat guy hired some competent folks to review all the charger/inverter/battery wiring. I have yet to get the report. It'll get sorted in the new few weeks.

This is also why I'm looking to add more instrumentation. Better to have sensors and alarms monitoring things rather than just letting them go unsupervised.
 
I've already committed to the idea that it's cheaper to rip-and-replace than it is to debug WTF is going on. I mean, why burn labor hours figuring out what's screwy when it may very well result in installing a whole new setup anyway? Probably not without spending more, of course, but at least it's not dozens of hours wasted figuring out "oh, it's crap, chuck it".

Or put another way by a pastor I know ....

I believe it is possible to raise from the dead.
It is part of my line of work.
However it is so much easier just to give new birth.
 
I wouldn’t throw the baby out with the bath water. Looks pretty professional, you might be replacing a bunch of stuff for nothing when the list could be addressed by adding some batteries or something to the other side...
 
"but at least it's not dozens of hours wasted figuring out "oh, it's crap, chuck it"."

Someone went to a lot of time and hassle to build the system
.Perhaps the engineering is excellent?

Most DC setups are simple enough to be understood in about 15 min.

Might be worthwhile to look to see what you actually have before junking it.
 
"but at least it's not dozens of hours wasted figuring out "oh, it's crap, chuck it"."

Someone went to a lot of time and hassle to build the system
.Perhaps the engineering is excellent?

Most DC setups are simple enough to be understood in about 15 min.

Might be worthwhile to look to see what you actually have before junking it.

+1
 

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