Battery problem thoughts much appreciated!

[Paul L]

Originally Posted by john61ct

They are definitely Chinese, I believe Full River.

While it would be better if the built their own local production facility, it is likely Rolls is imposing tight specs and rigorous QA verification processes to protect their reputation.

Just as Apple and hundreds of brand owners do to get top-notch results out of Chinese OEMs.

But we haven't get decades of real-life reports about longevity in real life conditions yet, just like Trojan's AGMs, we're relying on the company's reputation.

Besides Lifeline, Odyssey also is a stellar AGM vendor, and Northstar. Firefly Oasis for PSOC situations.

Are you making these recommendations from actual use or just web reading? I've owned and cruised with Northstar, Victron and Rolls AGMs. There's no way I would ever recommend Northstar. Not only did they die in a year and fail to get supported by the manufacturer, but the exact same a battery I purchased had its 20 hr spec reduced after a year because it was hype to start with. Something like 220amp-hrs to 200.

The Victrons were good batteries. My Rolls AGMs are about 5 or 6 years old and in very good shape.

[hellosailor]

John-
WRT trusting professionals? I knew one watch repair man who was quite blunt about his policy: No drop-ins, no phone calls answered during the workday, because he couldn't be expected to deal with interruptions while he had his face buried in the guts of watches.
Hey, it made sense to me. Inconvenient to be sure, but it made sense. Even professionals are only human, trust is nice but "trust but verify" is way more reliable.

[Ip485]

I dont see how the bank could possibly have been murdered. Since new if it has run off grid at most it is for a few nights, and not that many days when I would expect supplemented with the 850W of solar they would not have been significantly discharged.

I have learnt a lesson about relying on the current gauge without guaranteeing that the batteries are brought up to full charge and recalibrating, but even so I have never allowed them to drop below 60% and as I say that maybe on half a dozen occasions at most.

We are off crusing long term hence the absolute requirment for a solid bank that I know works as it should.

I also understand now that I can run both chargers at the same time so I have 150 Amps of charging potential in addition to the solar panels and of course the oversized Balmar.

I shall be interested to see what Rolls say and will decide then the route to take. In theory they are fully covered by their guarantee. If they are not for any reason I may consider going back to Lifeline or Lipo if the current chargers are compatible. I am not bothered about the cost, I am very bothered about as bullet proof a system as achievable, and rather hoped that was what I had with the new Rolls!

At least with the new found knowledge the bank will not been abused when cruising, albeit perhaps more by luck it most certainly has not been in the past more due to lack of cruising!

I have no doubt we probably do use a reasonable amount of power. I dount we will be using the Sat TV as much, but there are plenty of electronics on board, as well as a big inverter, and large fridge, freezer and bottle chiller (albiet all with keel coolers and very well insulated). There is also an 8KW Genset.

[hellosailor]

" If they are not for any reason I may consider going back to Lifeline or Lipo if the current chargers are compatible."
OK, it may not be obvious but it is part of "Lithium 101". NO CHARGER is compatible with proper lithium charging protocols, unless it was DESIGNED FOR THEM.
They really are that different from conventional lead batteries of any kind. It isn't just a matter of flipping a switch.
FWIW.

[Ip485]

OK - thanks. On balance it probably isnt worth replacing both the chargers as it would seem good quality AGMs should be up to the job - perhaps I have just been very unlucky with a bad batch.

Anyway the next step is to see exactly what the suppliers say. I am hoping the batteries will be removed next week. We shall see.

[john61ct]

If the batts weren't ever getting to Full, that can lead to a very early death.

If others were supposed to be responsible for adjusting the gear to do so, you might have a case.

But adjustable charge sources do need testing and tweaking over time to make sure endAmps is reached before dropping from Absorb to Float.

[john61ct]

Originally Posted by hellosailor

NO CHARGER is compatible with proper lithium charging protocols, unless it was DESIGNED FOR THEM.

Every one I've seen labelled "for LFP" is set way too high a voltage, usually hard-coded.

Adjustable chargers allowing custom profiles are the only way to go, if they have a canned LFP profile that should be ignored.

It is up to the owner to set their own definition of "Full".

LFP does not need to get there, certainly should not sit there.

[a64pilot]

Originally Posted by john61ct

If the batts weren't ever getting to Full, that can lead to a very early death

But adjustable charge sources do need testing and tweaking over time to make sure endAmps is reached before dropping from Absorb to Float.

This is how they get murdered. Both my very high quality chargers would if I let them drop into float way to early. I have a Magnum MS 2812, and a Sterling Pro Charge Ultra. I would have to turn off the Sterling and turn it back on at least three time to get the bank to full, and the Magnum I would force it to hold absorption voltage until I would see 3 amps acceptance and then I would terminate absorption.
I now have a Magnum BMK that will allow me set end amps when I’m on shorepower.
If you don’t get to full but stop short by only a few percent and do that every time, your bank begins to walk down in charge, eventually it’s heavily sulfated.
This morning I woke up to a bank at 68%, ran the generator for three hours charging batteries and making water, washing clothes, and that got the bank to about 93%, then at Noon we left the boat with nothing but refrigeration going, it took the rest of the day for 1000W of Solar to really truly get the bank to 100% that was about 7 hours of charging, roughly.
If you plug in to shore power and in three or so hours your charger is in float, your bank is not fully charged, it can’t be.
People who think their bank is fully charged on Solar by lunch, are mistaken, it can’t be, but I hear it often.

[a64pilot]

Read this, it may help. It is a Lifeline battery, but representative of pretty much any AGM battery.
The last bit of the article is real important, where he is explaining what 100% is.
http://www.pbase.com/mainecruising/e...on_agm_battery

[senormechanico]

Originally Posted by john61ct

LFP does not need to get there, certainly should not sit there.

POST OF THE DAY !

Thanks John

[Ip485]

This is how they get murdered. Both my very high quality chargers would if I let them drop into float way to early. I have a Magnum MS 2812, and a Sterling Pro Charge Ultra. I would have to turn off the Sterling and turn it back on at least three time to get the bank to full, and the Magnum I would force it to hold absorption voltage until I would see 3 amps acceptance and then I would terminate absorption.

I dont see how that equates with the way in which my bank has been used? Even in float I would imagine over the week in the marina the bank would be brought back to 100%.

I also take on board your very good advice for cruising BUT that is not the background to the issue I have had. In reality loads of owners leave boats in marinas connected to shore power and I dont hear of new battery banks lasting such a short time. In fact I suspect owners may well murder them to a much greater extent and they still survive for a reasonable time.

[Sailmonkey]

Originally Posted by Ip485

I dont see how that equates with the way in which my bank has been used? Even in float I would imagine over the week in the marina the bank would be brought back to 100%.

I also take on board your very good advice for cruising BUT that is not the background to the issue I have had. In reality loads of owners leave boats in marinas connected to shore power and I dont hear of new battery banks lasting such a short time. In fact I suspect owners may well murder them to a much greater extent and they still survive for a reasonable time.

The voltage supplied by float, no matter how long applied, isn’t enough to bring the cell chemistry back to the 100% charged specific gravity. To do this takes elevated voltage for an extended period of time. Float does just what it sounds like.....it maintains a specific state of charge, without adding to the state of charge.

[a64pilot]

First there is really no charging at all in float, float is set to keep the batteries from degrading, but if there is any real charge going in, then over time you will dry the batteries out.
Your right most batteries are Murdered, just of all different battery chemistries out there, AGM’s are the least tolerant of partial charging and are among the easiest to murder. Cheap Walmart golf cart batteries will tolerate it much better, and last much longer than a high quality AGM.
For the record I have a Lifeline AGM bank.

However of course you may have had one or more bad batteries, if Rolls outsources their AGM’s then maybe they are only Rolls on the label?

Without being there and being able to look at the bank and see how many amps are being accepted when the charger trips into float etc., it’s all speculation on our part.

[john61ct]

Originally Posted by a64pilot

Magnum MS 2812
…
force it to hold absorption voltage until I would see 3 amps acceptance
…
I now have a Magnum BMK that will allow me set end amps when I’m on shorepower.

Does Magnum sell just-chargers that work with the BMK like that? I have no interest in the inverter side.

And is there a user-custom profile for tweaking voltage setpoints?

Originally Posted by a64pilot

If you plug in to shore power and in three or so hours your charger is in float, your bank is not fully charged, it can’t be.
People who think their bank is fully charged on Solar by lunch, are mistaken, it can’t be, but I hear it often.

Unless of course SoC is barely down from full at the start of the cycle.

At least there are lots of solar controllers with very adjustable profiles, even BM integration for endAmps, etc.

Very disappointing the same is not true for mains chargers.

[a64pilot]

Right now, today my Sterling Pro Chrge Ultra, a pretty good charger, tripped into float with my bank at 90% SOC. I turned it off, waited until the remote control was blank, turned it back on, and it’s in Absorption again.
My bank is currently accepting 50 amps from three sources, two chargers and Solar, Solar is about 20 amps which isn’t bad for February. I’m heating water, Wife is washing clothes and in likely an hour I’ll be maybe 93% SOC and I will turn the generator off, and hope that Solar can get that last 7%, it may, it has a chance, it should have at least four hours to do it.

Did you read Maine Sails article? If not, do so it will explain a lot, in particular look at how long that last few percent of charge takes, you’ll spend more than 50% of your time charging chasing that last few percent, but that last few percent determines the life expectancy of an AGM bank, it’s the Achilles heel of an AGM bank.