Another AGM conditioning question

A bit more follow on info. But first, at 3:00PM today, again after the ongoing repeating of the Equalize/Condition four cycle at 14.4V, the Amp reading went up from 15 to 17 Amp. I thought yesterday just before noon, I saw the Amp number jumping/fluctuating quickly between 14.5 to 15 Amp - but perhaps it was wishful thinking:)! It never 'settled' below 15A at anytime that I saw.

On battery temps. The four batteries are locked down tight into a rectangle configuration, actually if you look at the smaller rectangles of each battery, their four rectangles, making one larger rectangle. The longer side of the rectangle is facing the battery compartment opening. So I have long side of two batteries facing me, and was shutting the infrared at the top in the middle cap like item on each cell, and then I also went down the front side of the battery on each cell of these two batteries. With todays low to mid 80's outside, the temperatures read 86.0F + or - .4F degrees between cells. The middle cell, as well as the two end cells that were next to the each other between the two batteries, were usually the .4F degree higher then the outside end cells. I do want to clarify the four batteries are not in direct contact with each other, a little under half inch spacing between each battery.

I could read the top of the back two batteries, and the same variation, but the + or - varied by .6F, I could also shoot the end of one of the back two batteries (The other is too close to the side of the compartment to get a shot.) and all up and down the end cell. it was within .1F of the reading I got on the top of that cell.

Ok, so now a wonder I have, and could not find in the Magnum manual. Is it possible the Equalize phase is set to never drop below 15A?

And right or wrong, I've stopped the feed of 14.4V when I saw for the second time, the Amps going up a bit, and never seeming to drop below 15A. I'm a layman for sure compared to many of you on this forum, but my thinking was I'm probably doing the batteries no good by doing all of this... If they've had the bulk of their magic juices consumed - concerned I've just been consuming more of the little that maybe left.

For grins, I turned on both the MidNite Classic 150 controller, and set the Magnum back to normal Charge mode. Within 15 mins, both were showing Full (Magnum) or Resting (Classic) And both indicate 100% SOC.

I did reset my Magnum recorded life of battery (Well, last 4 1/2 years with the Magnum in.) Max AH Out to zero. It was 4259.2, which is easier just rounded up to 4800 to some what account for the first 6 months. (Very little usage during that six months, as we were not retired then. The coach was plugged in and maintained by the previous 3 stage charger, set as close to the Lifeline parameters as possible. So that is probably more AH Out then actually occurred during that 6 months.

Help me with the math on this gang.

Lifeline says rated at 1000 DOD Life Cycles at 50% utilization.
50% of 800AH bank is 400AH per cycle
400 x 1000 - 400,000 AH's over the life expectancy of the battery in ideal circumstances
Since ideal circumstances are not a reality. Being conservative I'll use 300,000 AH's available
Rounding up as I did to 4800 AH Out, heck add another 1200 for extra cushion and say 6000 Max AH Out

6000 used is no where near 300,000. Using the Lifeline Tech call reviewed and supported OK of the Magnum Lifeline AGM1 setting - I remain convinced the battery bank had an easy life. (Or, like to think so.)

Is my thought process correct on the above?

I do have an email into Lifeline, and have not heard back from them yet.

Oh well, real test will be tomorrow night when the sun goes down, and generator hours are over here in the park. We'll see if the last few days of Multiple Conditioning and the last mostly steady 14.4V feeding.

It will be, what it will be:)!

Best to all,
Smitty

The batteries need a full on CCA carbon pile load test. Battery voltage will dump to around 8-volts and stay there even with high amperage load. Alternative is to charge them and let them sit a month.

Reality is to use them and if they work good enough to satisfy without robbing charging from the good batteries - then why not? Either they'll work or they won't.

But now it is on my workshop floor and in June will have been there for 3 years. mostly shallowly cycled.
Not sure whether just shooting the battery lid with IR gun inbetween cell dividers, will show the whole story with an AGM.

Right! A more localized diagnosis can be found by using hands and fingers on the case sides.

A handheld meter is also more focused than relying on a battery meter.

For those pushing big amps into batteries, I'd recommend placing a milk carton and board or even a cardboard box over the battery while charging thusly. If the battery has a short and blows its top, some containment is better than no containment.

Good luck to those with misbehaving batteries!

That much amperage still flowing makes me think that you have some unknown DC load which is showing up on your ammeter as charging current.

NO cables, other than a battery temperature sensor, should goto the battery (-), that does not come directly from the battery side of the shunt.

I'd think 15 amps which never taper would have even 800AH of batteries heating. How much hotter are they than ambient?

My one flooded battery had one cell that was getting 10 degrees hotter on the bottom of the cell than the top or the other 5 cells, and this had me remove it from my rig.



But now it is on my workshop floor and in June will have been there for 3 years. mostly shallowly cycled.
Not sure whether just shooting the battery lid with IR gun inbetween cell dividers, will show the whole story with an AGM.

Sticking 350 amp hours into a 150 amp hour battery is a pretty sure sign all is not right in River City.

This is *exactly* the reason why I was looking for a resettable upcount ampere hour meter.

LY,

I'm checking regularly for temps using infrared gun. 75.4 - 76.3 measuring each cell among the laser light at the center of the cap. (Well, not the cap, but the plug where caps would be on a cell. Sometimes the center cells are tad warmer then the outside cells of a battery, but within .2F of each other.

My source for charging is the Magnum MS2812, I'll read the various manuals again to see if I've missed a setting. But the only way I've found to set a voltage and have it go in at that specific voltage for a given period of time, is by Equalizing. I've set the Custom profile to 14.4V, which matches the Absorb setting to. The MS2812 when set to Equalizing, runs 4 hours. The ARC50 Remote, displays Equalizing and gives voltage 14.4V and Amps. When the Equalizing shuts off, or now I'm shutting it off myself when it's over 3 1/2 hours, and then I 'restart' the Equalizing. The Amp display ups to 26-29A, then over a 10-15 mins, works down to the teens. Usually to 15A, though this AM when I went out to stop and restart the Equalizing - it was 19A. (On shore power, and the Inverter in the Off position. So minor parasitic draws on the house bank.)

I have power until 10:00-11:30AM tomorrow (Friday), when I must move to a boon docking site, so I have about 28 more hours that I can keep doing the feed of 14.4V. But we then bounce back to a Shore Power site for one more day on Saturday. So I'll do the 14.4V feed again as long as I can on that move. We move Monday to a boon docking site for the balance of our stay at Lost Dutchman State Park which is Friday 3/16. And the 10 day forecast is Cloudy and Partly Cloudy for that period. So will use Generator and Solar to keep the batteries up.

I will double check my MidNite 150 Classic controller settings, but pretty sure I can change the Absorb time. 14.4V, to run longer. I'll set that for as long as it allows me.

The other thing I'm trying to find, is how to get into the Magnum ARC50 to see the Magnum's last record of Reaching Full Absorb. I saw that on one of the drill down's while scanning the manual PDF, but the 03x settings are a bit different because of the BMK Meter. So have not been able to find the last time that Magnum recorded a Full Absorb cycle. (Maybe it's not available with the BMK Meter module in the mix(?) - but still checking the various manuals.

As I finish this post, I just looked and the ARC50 is displaying Equalize 14.4V and fluctuating between 19-18A. Which since I've not drawn any power to speak of out of the battery bank, is probably not a good sign. As it had held 15A for several hours as I monitored it off and on during the day.

Best to you and all,
Smitty

Holding 15 amps? no tapering? They have to be going somewhere. You feeling for hot cells on those batteries?

BFL13, LY, MW - Thanks again~!

And BFL13. Pretty good assumption you understand, it's me that does not do a 'Duh!' how can this be 12.7V 30 mins after be 12.7V? You know 'It's not you, it's me...'.

Watching temps via ARC-50 Magnum Temp Sensor, which is very close to the battery Infrared Temp readings. I did the posts, I'll do some scanning where I believe the Cell's should be, to see if temps vary on a specific battery cell.

If the battery temps look good, I'll continue the 14.4V... Now 1.5 hours into the second cycle of 4 hours. Still holding 15A:)!

Side question. I validated that the 9" Interconnects are #3 welding wire. That passes my filters, but I've proven I've been wrong before. His that an appropriate gauge of wire for 6V 400A connections?

Best,
Smitty

As long as every single cell avoids overheating apply 14.4 volts even if it takes four days at 24 hours per day charge time. Naio's predicament is she feels sensitive about over-amping the Megawatt which is a valid concern. It is a tough power supply but reasonable is reasonable. It is designed to augment a properly sized converter, not replace it.

AGM batteries have a formidable charge acceptance. With the 2-story Lifeline 31 I have whacked it with 137 amperes to achieve 14.4 absorbsion 14.4 volts limit.

My error with Naio is I somehow believed she was dealing with wheelchair batteries. So right off the bat I was standing on non-existent ice.

By virtue of physics and chemistry only a cell short or multiples thereof can cause an AGM battery to overheat if voltage limited charging is employed. So checking the battery by hand (an infra red scanner is easier and best) will reveal excess heat either in a single cell or series cells.

WEAR EYE PROTECTION! Please! I mean it!

Once a rig's converter set at 14.4 volts has amperage slump to LESS than the power supply's max amperage limit, then the power supply can constant voltage charge the battery for hours and even days if required.
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Let's use some common sense in diagnostics...

A 135 amp hour AGM as an example.

Connect a charger to it -- converter or power supply it does not matter

Over whatever amount of time it takes, by keeping track, and voltage limiting to 14.4 it seems as though the 135 amp hour battery has taken 290 amp hours worth have charging and has not had its amperage decline to one half percent of total amp hour capacity (in this case less than 6.75 amps)...

The battery is bad

If amperage ALMOST declined to 6.75 amps than try the battery under load and if it works to your satisfaction then it works. If it falls flat on it's face it fails meaning a bad battery.

Think of a five gallon bucket. If you jam 6 gallons into it, is it a five gallon bucket? No. It has a leak. A battery operates on chemistry so the leak can be twiddled with -- to a point. By equalization or conditioning charging.

If it fails to respond to equalization or conditioning twiddling then you have a bad battery.

If you want to be snotty about the protocol

All batteries have a charge efficiency factor measured in percentage of overcharge needed to bring a discharged battery to full charge from being discharged.

A neglected battery has a moderate fault in amp hours needed to return to full charge

A bad battery can never be returned to full charge. Endless charging, never reaching one-half percent of amp hours at 14.4 volts, or reaching the magic figure but then rendering a notable lack of ampere hours of charge storage.

The lack of charge storage can be treated with conditioning. The never reaching the one-half-percent even with ridiculous amounts of excess amperage at 14.4 volts is like allowing an at bat hitter slack. But "Strike twenty-seven you're out" should be ample proof the battery is scrap.

Hope this helps...

"Then the third day, one again I saw Full Charge on the Magnum, and read a full bank of 12.7V at the battery with Multi Meter."

Does not compute. When the Magnum at say 14.4 gets the batts full, they should be at 14.3999999v

Then if you disconnect the batts from all loads and charging, they should be at 13.x right away, and then not get down to 12.7 for a couple of days. Except AGMs which will rest at more like 13 instead of 12.7