Bought the Oasis Firefly Battery

[SternWake]

Edit window missed.

When amps taper to 0.6, not 'near Zero' as i wrote above.

Seems firefly has more documentation than 6 months ago.

http://www.bruceschwab.com/uploads/firefly-psoc-partial-state-of-charge-sweet-spot-2-2014.pdf

http://www.bruceschwab.com/uploads/firefly-users-manual-january-2017.pdf



They are now saying to avoid floating.

 

[John61CT]

Strange that they did not give a recommended load at which to discharge the battery to 10.5v. 

Nigel and Bruce at OceanPlanet Energy oceanplanetenergy.com, and Maine Sail are the experts on these, they are also friendly with Kurtis Kelly, the original inventor of this battery and Carbon Foam tech, who lives nearby them in Maine.

Not to mention Firefly tech support, not as if any of these people are that hard to reach either online or IRL.


> But this chart shows a 50 amp initial current on one battery, so we know it is capable of accepting that much.

Battery's spec sheet gives a max input charge rate of 250A. I doubt it will actually accept that much for long, these LA aren't like LFP (3xAH rating!)

From the batt's manual:

"To perform the restoration charge: charge the Oasis to 14.4V and continue to charge until the current drops to 0.6 A."

Then drop-to-10.5V under load (electric heating element, blow dryers would do)

Then the full charge cycle again.

Then repeat, in this case maybe twice.

All if not on a bench, but certainly under controlled conditions and observed frequently.

I would think a 20A charge rate would be at the low end, and obviously requires being able to accurately measure and strictly control A and V.

If I didn't have the right equipment I'd bring it (and a printout of the charge specs) into an auto electric shop at least, marine outfit would be better.

And avoid the PSOC cycling as much as possible from now on.

Treated well by normal AGM standards, this puppy can go 9000 30% cycles!

 

[cortttt]

Nigel and Bruce at OceanPlanet Energy oceanplanetenergy.com, and Maine Sail are the experts on these, they are also friendly with Kurtis Kelly, the original inventor of this battery and Carbon Foam tech, who lives nearby them in Maine.

Not to mention Firefly tech support, not as if any of these people are that hard to reach either online or IRL.


> But this chart shows a 50 amp initial current on one battery, so we know it is capable of accepting that much.

Battery's spec sheet gives a max input charge rate of 250A. I doubt it will actually accept that much for long, these LA aren't like LFP (3xAH rating!)

From the batt's manual:

"To perform the restoration charge: charge the Oasis to 14.4V and continue to charge until the current drops to 0.6 A."

Then drop-to-10.5V under load (electric heating element, blow dryers would do)

Then the full charge cycle again.

Then repeat, in this case maybe twice.

All if not on a bench, but certainly under controlled conditions and observed frequently.

I would think a 20A charge rate would be at the low end, and obviously requires being able to accurately measure and strictly control A and V.

If I didn't have the right equipment I'd bring it (and a printout of the charge specs) into an auto electric shop at least, marine outfit would be better.

And avoid the PSOC cycling as much as possible from now on.

Treated well by normal AGM standards, this puppy can go 9000 30% cycles!

Thanks... I took the description I posted right out of the manual I had...I guess it's changed...

I've been dealing extensively with the Firefly rep I bought the battery from. There are only a few in the country but it looks like I should try elsewhere.

 

[cortttt]

Edit window missed.

When amps taper to 0.6, not 'near Zero' as i wrote above.

Seems firefly has more documentation than 6 months ago.

http://www.bruceschwab.com/uploads/firefly-psoc-partial-state-of-charge-sweet-spot-2-2014.pdf

http://www.bruceschwab.com/uploads/firefly-users-manual-january-2017.pdf



They are now saying to avoid floating.

Interesting. In the manual it does say that it does not need floating..

 

[cortttt]

I would have interpreted it to mean draw down over an hour or two, not over a whole day. And I'd either be watching the voltage drop like a hawk, or (better) have an LVD wired to cut the load off automatically at the cutoff voltage.

And that routine should only be as-needed if you were being PSOC abusive right? Not as a scheduled routine?

Normal LA and all other AGM would be pretty instantly murdered by such abuse. The native chemistry really wants to get back up to 100% as quickly and as often as possible, and especially with the $$ Firefly that should be what you'd aspire to in daily use right?

Amazing their foam tricks result in such difference in resilience. But in this case maybe pushed too far. . .

>> Personally this noob

Sorry didn't mean to snark, was only referring to myself.

Thanks

I now wonder if it was the extended discharge at low levels that did it. Rickey never gave me a time frame for that nor did the manual.  Plus I did miss a day checking the voltage.  I had no idea that it was going to plummet like that. It went from 11.3 to 5.0 volts (perhaps 7.0) in two days. I wonder if the fluid loss from the bad vents played a role. 

Rickey suggested doing a restoration charge every couple of months. 

Then there's the weird behavior of the Morningstar controller. I am going to call them right now. Is it broken? 

The good side is that I am being forced to learn more about batteries - which I probably should anyway (lol)

 

[cortttt]

Double check the tightness of the wires where they enter and exit your solar controller.  Is the weight of the wires hanging off the terminals? Really it would be best to make sure they cannot vibrate and there is NO stress on any wire terminal.

https://www.amazon.com/Ancor-400000...&qid=1485831134&sr=8-11&keywords=cable+clamps


If the wires were hanging and vibrating with the engine, it is possible the solder joints on the circuit board, where the wires enter/exit, could have fractured and give intermittent Readings.

The tighten stranded wire under screws  terminals are problematic.  They need to be retightened occassionally, especially withing the first week of originally crushing the wire under the screw. This copper can oxidize and develop more resistance with time, and then heat up more, accelerating the degradation process

Strange that they did not give a recommended load at which to discharge the battery to 10.5v. 

As a minimum, I figure one needs to use the load at which the battery the battery earns its 20 hour capacity rating.

So 110AH rating divided by 20 hours is a 5.5 amp load.  So, if one wanted to keep the battery around 77f, and could discharge it at exaxtly 5.5 amps One could judge the remaining capacity by hol long it took voltage to hit 10.5volts.

It is not easy to have an exact 5.5 amp load  the whole test when voltage drops  as battery discharges, nor keep the battery at 77f for the whole test for the results to be precise and accurate.

BUt, at a later date, one could do the same test using the same load and compare the time it took to fall to 10.5v and judge fairly closely to how much capacity has declined and can estimate how much is remaining.

Also when recharging from this 10.5v, it should be done in one session, not getting to 50% day one then 98% day two and 100% day 3.

Ask your contact about minimum/maximum initial amperage.

But this chart shows a 50 amp initial current on one battery, so we know it is capable of accepting that much.

Odyssey AGM says use 40% of the 10 hour rate of the battery as a minimum when conditioning.

http://www.odysseybattery.com/documents/ODYSSEY_Battery_Reconditioning_Charge_Procedure.pdf




Odyssey's group31(pc2250) is 100AH at 20Hr rate, and 92AH at the 10 hour rate.

That would be 38.6 amps Minimum recommended.   This 39 amps might take nearly 2 hours before battery voltage climbs to 14.7v.  Then 14.7 needs to be held until amps taper to near Zero.  This might take 4 hours if the battery is healthy. It might take 18 hours. 

I would not recommend trying an AGM  'reconditioning' procedure, unless one is willing to apply a big enough load  to battery to take battery voltage to 10.5 in an hour or 3, but certainly no more than 20 hours.   Under no circumstances allow it to drain below 10.5v at the 20 hour rate, but a 3 hour rate can goto 10.0v as it will likely rebound above 10.5v when ~30 amp load is removed

When battery is this depleted, the most importat part begins. that is applying a minimal amperage until 14.4 or .7v at 77F, is attained.  The this absorption voltage is to be held until amps taper near zero.

When you discharged the battery, you did so only with the fan? Not sure of the amp load, but I will guess That would be 1.2 amps or so, like a hundred hour rate, and once battery voltage fell to 10.5v, it then took a nosedive as it is fully depleted at 10.5v under a 5.5 amps load.  A 1.1 amp load drained it well past 100% depleted even if you stopped it at 10.5v.

Any time spend below 20% charged is bad time for a battery.  When taking it there the goal should be to get it back above 20% quickly, and ultimately back to 80% in 2 hours, and 80 to 100% might take 4 more hours, or 14, but it is important to hold it at absorption voltage until amps taper to near Zero.

Obviously this requires special equipment, Or a GOOD excess fo solar, and if it cannot be done in one day via solar, do not discharge the battery at all that night, and then park so the solar panel will get the early morning light, and dance on one foot backwards clockwise while chanting and hold absorption voltage until amps taper to near Zero.

If one can't Apply  the true 100% recharge promptly, ASAP,  after this  100% discharge , all this 'reconditioning' procedure, becomes, is an extra abusive deep cycle.

110AH capacity battery discharged to 10.5v under a 1 amp load is abusive
The discharge to 7 volts under a 1 amp load is extremely abusive.

100% dischrge shold be done at the 20 hour rate, at the minimum, 5.5 amps on this Oasis 110Ah battery for 20 hours, And I think it is better if can be done  in 3-4 hours.

I cannot say I ever heard My AGM bubbling when charging at 40 amps, but it does increase temperature nearly 20 degrees at that rate by the time amps taper to about 15.

Don't know what to say about the caps leaking, other than to wonder if you tightened them enough, or if the surface they mate to is not flat.

If you pass through San Diego, I can perform the 'reconditioning' and lend you a fully charged healthy enough group31 12v flooded battery overnight.  I expect I could not do it in less than 11 hours.  it is up to the battery.

Thanks again for your help. I would love to have you check out this battery and see what you think.  I do have the ProNautica charger that Rickey suggested but have not used it yet. 

I am also going to write up the entire story and give it to some Firefly experts. 

I will check the connections again but I'm pretty sure that they are good. (They were not put in by me, no strain on the wires - very protected - really a superb job by 29Chico..)

Vibration is another story...Something seems to have gone wacky with the controller. I can see from your explanation how the battery voltage might shoot up - but not how it might drop so much. 

Yes I only used the MaxxAir Fan. Two people have measured its amp draws at the lowest setting.

[font=verdana, geneva, lucida,][size=small][font=verdana, geneva, lucida,]" [/font][font=verdana, geneva, lucida,]On low[/font][font=verdana, geneva, lucida,] it only drew about 0.3 Amps after it got going. If it were run 7 hours it would only draw about 2AH."[/font][/font][/size]

[font=verdana, geneva, lucida,][size=small][font=verdana, geneva, lucida,]http://www.fiberglassrv.com/forums/...ir-fan-for-7-hrs-off-my-rv-battery-42516.html[/font][/font][/size]

[font=verdana, geneva, lucida,][size=small]I used the next lowest setting. [/font][/size]

[font=verdana, geneva, lucida,][size=small]If I had known better I would have brought it down to 10.5 volts much more quickly[/font][/size]

Obviously this requires special equipment, Or a GOOD excess fo solar, and if it cannot be done in one day via solar, do not discharge the battery at all that night, and then park so the solar panel will get the early morning light, and dance on one foot backwards clockwise while chanting and hold absorption voltage until amps taper to near Zero.

Ready to start chanting if that will help 

 

[cortttt]

Another question I have is if having the battery hooked up to the solar with no load on it is harmful. I had trouble with the fridge and disconnected that. With that I'm only occasionally using the fan and powering the computers, cell phone and tablets. 

I assumed that the controller would just shut off charge to the battery when the battery is full?

 

[SternWake]

If it were not for the fact that it is a 500$ battery, it would be funny that your attempt at a restoration charge is basically the most absuive deep cycle you could have performed.


Taking the battery to 5 volts at say a 0.5 amp load intentionally is just about the most absuive thing I can imagine doing. Its like battery torture.

A 12v battery when depleted to 10.5v, will always drop off very fast after that, if load is still applied and can still run at those lower voltages as there is no useful energy stored below 10.5v.

When the battery is full, the solar controller should be dropping to float and the battery should be accepting very few amps at float voltage.

Float stage is designed to keep a battery full, basically prevent self discharge.  If there are minor loads present, less than the solar can handle, it keeps the battery full through those.

FF recommending not floating, is if the battery were disconnected from all loads.  They would have so little self discharge that there is no need for continuous floating, and since they claim that sitting in an undercharged state is not abusive to a Firefly, then floating is actually detrimental.

What is the maximum amperage of your pro nautique charger?

I am sure 29Chico properly torqued the screws holding the wires, but these types of terminals where one crushes stranded wiring need to be retightened after a while, and occassionally thereafter.

I really dislike these types of electrical terminals for this reason. They might be easiest to manufacture and for a Novice to wireup themselves, but their longevity is horrible as the copper is nearly fully exposed to air and will oxidize and corrode and become resistive.  I big blog of Dielectric grease can help stave off oxidation, but then the screw can more easily back off/loosen.

If the act of simply moving the battery changes its voltage, and the voltmeter is not to blame, it could have a shorted cell, which could explain the bubbling you hear.

 

[cortttt]

If it were not for the fact that it is a 500$ battery, it would be funny that your attempt at a restoration charge is basically the most absuive deep cycle you could have performed.


Taking the battery to 5 volts at say a 0.5 amp load intentionally is just about the most absuive thing I can imagine doing. Its like battery torture.

A 12v battery when depleted to 10.5v, will always drop off very fast after that, if load is still applied and can still run at those lower voltages as there is no useful energy stored below 10.5v.

When the battery is full, the solar controller should be dropping to float and the battery should be accepting very few amps at float voltage.

Float stage is designed to keep a battery full, basically prevent self discharge.  If there are minor loads present, less than the solar can handle, it keeps the battery full through those.

FF recommending not floating, is if the battery were disconnected from all loads.  They would have so little self discharge that there is no need for continuous floating, and since they claim that sitting in an undercharged state is not abusive to a Firefly, then floating is actually detrimental.

What is the maximum amperage of your pro nautique charger?

I am sure 29Chico properly torqued the screws holding the wires, but these types of terminals where one crushes stranded wiring need to be retightened after a while, and occassionally thereafter.

I really dislike these types of electrical terminals for this reason. They might be easiest to manufacture and for a Novice to wireup themselves, but their longevity is horrible as the copper is nearly fully exposed to air and will oxidize and corrode and become resistive.  I big blog of Dielectric grease can help stave off oxidation, but then the screw can more easily back off/loosen.

If the act of simply moving the battery changes its voltage, and the voltmeter is not to blame, it could have a shorted cell, which could explain the bubbling you hear.

Darn. I accidentally tortured the battery.  I wish I had known about how to do that restoration charge properly. 

ProNautic = 20 amp

https://www.amazon.com/gp/product/B004NPL8JU/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B004NPL8JU/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
I will check the screws holding the wires. 

If I took the battery to say Autozone would they be able to detect if a cell is out?

 

[John61CT]

Thanks

I now wonder if it was the extended discharge at low levels that did it. Rickey never gave me a time frame for that nor did the manual.  Plus I did miss a day checking the voltage.  I had no idea that it was going to plummet like that. It went from 11.3 to 5.0 volts (perhaps 7.0) in two days. I wonder if the fluid loss from the bad vents played a role. 

Rickey suggested doing a restoration charge every couple of months. 

Then there's the weird behavior of the Morningstar controller. I am going to call them right now. Is it broken? 

The good side is that I am being forced to learn more about batteries - which I probably should anyway (lol)

Yes! When playing pioneer with cutting-edge expensive gear best IMO to take responsibility and bone up, become an authority yourself.

When the top level techie-geeks are available to answer questions, I would never listen to someone sales-oriented, no matter how nice or well-intentioned.

Unless one is wealthy, but then you still have to do the legwork identifying the right experts to throw your money at.

I now wonder if it was the extended discharge at low levels that did it.

I didn't think that was in question? Unless something else catastrophically failed, certainly didn't do any good.

IMO would be miraculous if it came back up above 80% of its rated capacity and remained usefully functional for another year or two.

But what Calder and Maine Sail reported in Practical Sailor was miraculous, so we're keeping our fingers crossed for you. . .

 

[cortttt]

Yes! When playing pioneer with cutting-edge expensive gear best IMO to take responsibility and bone up, become an authority yourself.

When the top level techie-geeks are available to answer questions, I would never listen to someone sales-oriented, no matter how nice or well-intentioned.

Unless one is wealthy, but then you still have to do the legwork identifying the right experts to throw your money at.



I didn't think that was in question? Unless something else catastrophically failed, certainly didn't do any good.

IMO would be miraculous if it came back up above 80% of its rated capacity and remained usefully functional for another year or two.

But what Calder and Maine Sail reported in Practical Sailor was miraculous, so we're keeping our fingers crossed for you. . .

I thought I was listening to an expert (lol)  but that proved not to be.  I also expected that the instructions would be complete. That wasn't so either. No warnings about the dangers of slowly discharging the battery.  I had no idea...Definitely a lesson learned. 

Thanks...I would be happy right now if it lasted another year or two..fingers are crossed.

 

[SternWake]

Usually if a cell is shorted the maximum the flooded battery can be charged to is  a resting 10.8v, and the one cell will be noticably warmer when charging

.  The charging source will be able to get voltage higher especially a stronger one, but after the charging source is removed a battery with a shorted cell will quickly fall to 10.8ish volts

Sometimes a cell drops out under a load on the  damaged battery, but reads normal voltage with zero loads.

That is my experiences with Flooded batteries.

  But I saw a 18 year old Optima AGM, keep starting an Astro van, which I believe  had a shorted cell (10.6v resting) for many months after I declared it was worthless and recommended replacing it.

 

[cortttt]

Usually if a cell is shorted the maximum the flooded battery can be charged to is  a resting 10.8v, and the one cell will be noticably warmer when charging

.  The charging source will be able to get voltage higher especially a stronger one, but after the charging source is removed a battery with a shorted cell will quickly fall to 10.8ish volts

Sometimes a cell drops out under a load on the  damaged battery, but reads normal voltage with zero loads.

That is my experiences with Flooded batteries.

  But I saw a 18 year old Optima AGM, keep starting an Astro van, which I believe  had a shorted cell (10.6v resting) for many months after I declared it was worthless and recommended replacing it.

Thanks....The Firefly rep said he checked with the Firefly guys and they said that some bubbling was normal when the battery is in bulk phase. 

Spoke to Morningstar guy about the faults and weird log data problems and he had no clue either. He did feel that that battery should have been replaced after the substantial venting that occurred with the bad vents the battery came with. The fluid loss, he felt, would shorten the life of the battery. 

Right now battery and controller seem fine (lol)

 

[SternWake]

UNless each leaky cell barfed half a pint+ of electrolyte, you should be allright.

Hopefully you did not get any baking soda inside the cells, that would be very bad.

Glad to hear it is working OK.

The wacky readings of the Morning Star controller are a mystery, but perhaps related to seeing only 5 or perhaps 7 volts for a while.

IF you accidently ever drain the battery that far again, It is best disconnect everything from it.

if the SUN is out and you have solar, do not disconnect controller rom battery first, disconnect panels first, or throw something over them. Do not disconnect battery from solar controller when sun is shining, it could be destroyed.

The sub 10.5V battery should then be paralleled with a known good battery via jumper cables or similar.

Place a plug in charger on Good battery for an hour or two, then remove the other battery and restart charger on previously sub 10.5v battery.

If battery voltage was over 12.8v at the time of removing the other battery and trying to restart the charger, the charger might think the battery is full, and only seek float voltage, when one wants the charging source to seek 14.x volts. Never believe a smart charger when you attach it to a battery which recently saw other charging sources, and it claims the battery is already Full.

One needs to be smarter than such 'smart' chargers. Load the battery with something, until voltage drops below 12.6v, then restart charger, then remove load, and the charger should bo into 'bulk and seek absorption voltage.

When the Charger flashes the green light, and says fully charged, you can believe it if you want, but if you were able to check with a hydrometer it would likely prove the battery is not yet fully charged, and perhaps not even close to that ideal.

You can trick the charging source multiple times by applying that larger Load and dropping the voltage below 12.6v, restarting the charger, then removing load.

I once proved this to a skeptic who had incredible and unfounded faith in his charger, but I had to go out and buy a hydrometer to win the bet and get reimbursed for the Hydrometer. I won, but so did the battery as something like 11 restarts were required of a Schumacher smart charger before all cells of the battery were brought upto 1.270 or higher.

I was using an old Headlamp for a load, the high beam was close to 8 amps, and the last couple restarts it took some 15 minutes of presenting that load before voltage would fall far enought for charger to restart.

This is why I love my adjustable voltage power supply. Plug it in, set a voltage, attach it to battery, and let it go for as long as it takes. Can also adjust it afterwards. No trickery or restarting required, and I can bump voltage to way beyond what a battery should get. 19.23v is my Max, but 16.2v is the most I will allow, Unless I want to hear a battery gurgle and no loads are connected to it which could be damaged by such electrical pressure.

Am still willing to 'recondition' that firefly Cortt. Kind of interested to see how it compares to my 465 deep cycle 90Ah Northstar AGM-27 in performance, under my known loads, and charging sources. I want your battery to test well, as if it does I will likely eventually get one.

While I can do the 100% recharge thing, it would be nice if it were not a concern to achieve this ideal, but once monthly.

 

[cortttt]

UNless each leaky cell barfed  half a pint+ of electrolyte, you should be allright.

Hopefully you did not get any baking soda inside the cells, that would be very bad.

Glad to hear it is working OK.

The wacky readings of the Morning Star controller are a mystery, but perhaps related to seeing only  5 or perhaps 7 volts for a while.

IF you accidently ever drain the battery that far again, It is best disconnect everything from it.

if the SUN is out and you have solar, do not disconnect controller rom battery first, disconnect panels first, or throw something over them.  Do not disconnect battery from solar controller when sun is shining, it could be destroyed.

The sub 10.5V battery should then be paralleled with a known good battery via jumper cables or similar.

Place a plug in  charger on Good battery for an hour or two, then remove the other battery and restart charger on previously sub 10.5v battery.

If battery voltage was over 12.8v at the time of removing the other battery and trying to restart the charger, the charger might think the battery is full, and only seek float voltage, when one wants the charging source to seek 14.x volts.  Never believe a smart charger when you attach it to a battery which recently saw other charging sources, and it claims the battery is already Full.

One needs to be smarter than such 'smart' chargers.  Load the battery with something, until voltage drops below 12.6v, then restart charger, then remove load, and the charger should bo into 'bulk and seek absorption voltage.

When the Charger flashes the green light, and says fully charged, you can believe it if you want, but if you were able to check with a hydrometer it would likely prove the battery is not yet fully charged, and perhaps not even close to that ideal.

You can trick the charging source multiple times by applying that larger Load and dropping the voltage below 12.6v, restarting the charger, then removing load.

I once proved this to a skeptic who had incredible and unfounded faith in his charger, but I had to go out and buy a hydrometer to win the bet and get reimbursed for the Hydrometer.  I won, but so did the battery as  something like 11 restarts were required of a Schumacher smart charger before all cells of the battery were brought upto 1.270 or higher.

I was using an old Headlamp for a load, the high beam was close to 8 amps, and the last couple restarts it took some 15 minutes of presenting that load before voltage would fall far enought for charger to restart.

This is why I love my adjustable voltage power supply.  Plug it in, set a voltage, attach it to battery, and let it go for as long as it takes. Can also adjust it afterwards. No trickery or restarting required, and I can bump voltage to way beyond what a battery should get.  19.23v is my Max, but 16.2v is the most I will allow, Unless I want to hear a battery gurgle and no loads are connected to it which could be damaged by such electrical pressure.

Am still willing to 'recondition' that firefly Cortt.  Kind of interested to see how it compares to my 465 deep cycle 90Ah Northstar AGM-27 in performance, under my known loads, and charging sources.  I want your battery to test well, as if it does I will likely eventually get one.  

While I can do the 100% recharge thing, it would be nice if it were not a concern to achieve this ideal, but once monthly.

Thanks. I'll get down there in the next week or so and we can get this battery tested and see how it's withstood its time with me. This battery has been through a number of stressor including sitting in the van unused in very high temps for about a month, fluid loss, and recently being discharged over a relatively long period of to very low levels in what apparently amounted to an excruciating stress test.  It'll be interesting to see how it performs.

Plus there's the weird Morningstar issues. The logged data for yesterday states the voltage minimum was 7.6 volts which the rep explained is impossible as the controller will shut off and not turn on until the battery is recharged.  The rep could also not explain the high voltage disconnect problem as that should only occur if the panels are set up wrong (not in parallel) or if I was using an alternative power source such as the alternator - which I am not. 

On the other hand when the controllers burn out they usually get stuck in one mode or another and I'm getting these faults and they are clearing.

 

[BradKW]

So Corttt, what was the final solution or result with the battery?

 

[John61CT]

If this thread is the basis for your assertion the Firefly wasn't performing to a high standard, and casting aspersions on the integrity of Maine Sail, Nigel Calder et al, that was most unfair.

May I suggest you read right back to the catastrophic treatment OP unknowingly inflicted on the battery?

 

[jpaddler]

I've been interested in this battery myself, and had hoped for an update.

Alot of money to spend on an agm battery, but significantly less the a 100 ah lithium battery.

Especially if it can be used as its claimed.

Sent from my Nexus 6P using Tapatalk

 

[road_ahead]

Alot of money to spend on an agm battery, but significantly less the a 100 ah lithium battery.

Duracell/Deka-Penn 31's are $193 out the club door... 2 cost 20% less than than a single Firefly. What's the advantage $/kWh over the entire life?

Curious, what would be your buy $ point for 100Ah LifePo given the price of Firefly and 'bang for buck' AGMs?

 

[John61CT]

If you're talking AGMs, East Penn's aren't very good, and certainly nowhere near Odyssey Lifeline and Northstar.

Their quite good Duracell-branded FLA GCs are $180 the pair for 200+AH, and that's value can't be beat IMO. I don't advise AGM against FLA unless the install space or need for high CAR requires it.

Personally I think among those top AGM makers, Firefly's use case is solely their unique resistance to unavoidable chronic PSOC abuse.

I don't think they've proven themselves over a wide nor long enough experience in the market to be considered in that group yet otherwise.

LFP requires a **very** long time period for payback at 5-7 times the price for bare cells alone + BMS + specialized charging requirements.

But that is the ultimate solution in a PSOC context, and if coddled can eventually end up cheapest of all.