agms going bad (takeoff from liion, lfp, and lifepo4 thread)

RWB
RWB Solar Expert Posts: 168 ✭✭✭✭✭
niel wrote: »
rwb,
from you,
"My partner has thrown away 15 quality Hawker Odyssey AGM Batteries and other brands over the last year because they go bad if you store them for very long, and he charged them once every Month or so but it still did not help."

forgive my sidestepping here, but somehow this does not sound right as agms do not lose that much of their power during shelving as you are indicating. i have recently, as an experiment, left my sunxtender sit with no loads or float charge for a month just to see the result. the voltage hardly dropped at all and was brought back up in no time. i believe the measured resultant voltage was about 12.7v (exact reading i don't recall) and usually my rest voltage is in the range of 12.8-12.85v. it used to be about .05v higher for the rest voltage, but i'm not going to complain about a battery that is going to be 7 this year. knowing this i suspect there's more to the story as to why your partner is "throwing away" batteries. what of the warranties on those batteries if it's applicable?

Hey Neil there is nothing more to the story. He bought the batteries for portable systems he builds. He would make sure they were charged every month or 2 and eventually they would not hold a charge or you could not put any load on them without going completely flat.

Yes it's for sure weird but that's what has been happening to him. I think its crazy that its more than 1 battery brand doing this.

Any ideas on why this would be happening?

I asked about warranty and he said Blah I'm not buying any more of these batteries.

Comments

  • RCinFLA
    RCinFLA Solar Expert Posts: 1,484 ✭✭✭✭
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions

    If they are just stored, this would rule out excessive discharge. That pretty much leaves extreme overcharging when he does the top off charge as cause of damage.

    AGM's usually are lead-calcium composition which has relatively low self discharge. A couple of months between topping charge should not be a problem.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions

    For those with utililty power available to float their battery banks but do not have good "float charger"--I use a cheap 1 amp 12 volt wall wart and a lamp timer. I set the timer for 1-4 hours a day to keep an in-law's car battery charged (GPS, On-Star, lojack, etc.). Stopped the battery going dead after 6-8 weeks of not running the car, and no longer have to check battery water level once a month.

    Still does not help when the trunk is cracked open and the trunk light is on for a month :grr.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions
    RWB wrote: »
    Hey Neil there is nothing more to the story. He bought the batteries for portable systems he builds. He would make sure they were charged every month or 2 and eventually they would not hold a charge or you could not put any load on them without going completely flat.

    Yes it's for sure weird but that's what has been happening to him. I think its crazy that its more than 1 battery brand doing this.

    Any ideas on why this would be happening?

    I asked about warranty and he said Blah I'm not buying any more of these batteries.

    i don't think he is taking good care of them for if it were not his fault he would insist on replacing them with the warranty. on top of it all as you said, it is not just one brand he's doing this to. i suspect he's draining something from them either something accidentally amiss in his designs or outright taking some of the battery ahs without replacing them and storing them as is. i believe sunxtenders list as 2-3% loss per month and i'm sure others are probably under 5%. at 5% that's 20 months to 100% dod, but sulfation would most likely be part of that equation before 20 months have gone by so they were abused somehow imho.
  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions

    I have a 12V 115AV AGM that has been off line in unheated garage since August 2009. (Prior full charge.) Brought it inside a couple of weeks ago and finally put the (Korean) DVM on it today. 12.81V. It's about 3 years old.
  • RWB
    RWB Solar Expert Posts: 168 ✭✭✭✭✭
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions
    niel wrote: »
    i don't think he is taking good care of them for if it were not his fault he would insist on replacing them with the warranty. on top of it all as you said, it is not just one brand he's doing this to. i suspect he's draining something from them either something accidentally amiss in his designs or outright taking some of the battery ahs without replacing them and storing them as is. i believe sunxtenders list as 2-3% loss per month and i'm sure others are probably under 5%. at 5% that's 20 months to 100% dod, but sulfation would most likely be part of that equation before 20 months have gone by so they were abused somehow imho.

    No these are batteries that are just sitting on the shelf, nothing is hooked up to them. I think most of them were past the 1 year warranty. He probably could replace them under some prorated warranty but he is rich basically and wants to get away from Lead Acid Batteries so he's just over them.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions

    rwb,
    you have missed my point in that they do not go bad after a few months sitting on the shelf even if out of warranty and no charge to them. mine is 7yrs old this year and did not show any sign of being anywhere near dead after a month as it may have lost only a few % of its capacity. he is not disclosing the full truth on these batteries going bad.
  • RWB
    RWB Solar Expert Posts: 168 ✭✭✭✭✭
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions
    niel wrote: »
    rwb,
    you have missed my point in that they do not go bad after a few months sitting on the shelf even if out of warranty and no charge to them. mine is 7yrs old this year and did not show any sign of being anywhere near dead after a month as it may have lost only a few % of its capacity. he is not disclosing the full truth on these batteries going bad.

    I got your point Niel, I'm just saying his experience is different than yours.

    Letting them sit and charging every month or 2 left him with a bunch of dead batteries. Nothing else happened that could have been left out. Some of these batteries were smaller AGM Cells like 6.5 Amp Hours, 10, 15, 20, 26 Amp Hour ranges, not all of them were big 100-200 Amp Hour batteries like your probably thinking they all are.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions

    capacity should not matter.

    do note that my sidestepping comment in the thread has blossomed so i separated it into its own thread.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Lithium Iron Phosphate Batteries; LFP; LiFePO4 discussions

    Smaller sizes? I wonder if they were GEL instead of AGM ?
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
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  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Re: agms going bad (takeoff from liion, lfp, and lifepo4 thread)

    Either that, or that periodic charge was too much. He must have been doing something that hurt them. It is just not reasonable to imagine that all these batteries from different mfgs and of different sizes would all fail in a manner that is contrary to the experience of so many people. Unless.... he's just really unlucky.... or has bad karma.... or there is a space-time discontinuity near the place of storage where the normal laws of physics have been altered. ;)
  • RWB
    RWB Solar Expert Posts: 168 ✭✭✭✭✭
    Re: agms going bad (takeoff from liion, lfp, and lifepo4 thread)

    What if the batteries were stored on a concrete floor?

    I know some were on a wood shelf, I am only assuming that maybe some were on a concrete floor, I will have to check on that.

    I agree with you guys that its weird, not normal.
  • john p
    john p Solar Expert Posts: 814 ✭✭✭
    Re: agms going bad (takeoff from liion, lfp, and lifepo4 thread)

    can you really get AGM batteries this small?? Some of these batteries were smaller AGM Cells like 6.5 Amp Hours, 10, 15, 20, 26 Amp Hour ranges:confused:
  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Re: agms going bad (takeoff from liion, lfp, and lifepo4 thread)
    RWB wrote: »
    What if the batteries were stored on a concrete floor?...

    Not a factor. See Batteries on Concrete. From HomePower.

    Even as late as 1960, my grandpa, when he took his southerly vacations from Minnesota winters, insisted on removing his (fully charged) vehicle battery, (OK that's good practice) but also insisted it be stored on the workbench (not on the concrete floor,) in the basement (not in the garage!) Unnecessary! Try telling him that! And of course, at that time.... I couldn't.

    Shift of Cosmic Axis is more likely. :p

    Howard found himself on Earth due to a shift in "the Cosmic Axis" from a world similar to Earth, but where there are "more ducks" and "apes don't talk."
  • RWB
    RWB Solar Expert Posts: 168 ✭✭✭✭✭
    Re: agms going bad (takeoff from liion, lfp, and lifepo4 thread)
    john p wrote: »
    can you really get AGM batteries this small?? Some of these batteries were smaller AGM Cells like 6.5 Amp Hours, 10, 15, 20, 26 Amp Hour ranges:confused:

    http://www.batteriesplus.com/products/100085-1/102629-SLA-Sealed-Lead-Acid-Batteries/102645-Werker/12V/1.aspx
  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Re: agms going bad (takeoff from liion, lfp, and lifepo4 thread)
    john p wrote: »
    can you really get AGM batteries this small?...

    Yes, you can, believe it or not.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: agms going bad (takeoff from liion, lfp, and lifepo4 thread)
    john p wrote: »
    can you really get AGM batteries this small?? Some of these batteries were smaller AGM Cells like 6.5 Amp Hours, 10, 15, 20, 26 Amp Hour ranges:confused:

    small agms are very popular these days in computer backups and other items such as to run the modem for verizon fios fiber optics for phone, internet, and tv during brownouts and blackouts. i wish they made provision for fitting larger batteries for extended timeperiods of being without power on my fios. pc backups' too.:roll: all mine only fit about a 7ah battery.:grr
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: agms going bad (takeoff from liion, lfp, and lifepo4 thread)
    Kamala wrote: »
    Not a factor. See Batteries on Concrete. From HomePower.

    Even as late as 1960, my grandpa, when he took his southerly vacations from Minnesota winters, insisted on removing his (fully charged) vehicle battery, (OK that's good practice) but also insisted it be stored on the workbench (not on the concrete floor,) in the basement (not in the garage!) Unnecessary! Try telling him that! And of course, at that time.... I couldn't.

    The "don't store your batteries on concrete" actually has a basis in reality. But it has nothing to do with the batteries! It's the concrete you're protecting; it is basically an alkaline solid, and battery acid spilling on to it will etch the concrete. Won't harm the battery any.

    This bit of worthless historical trivia is brought to you be Cariboocoot; old and almost entirely useless! :p