LFP or LifePo4: questions about using

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  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    #32
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    Re: LFP or LifePo4: questions about using
    Cariboocoot wrote: »
    If you only get 400 cycles from lead-acid you are doing something horribly wrong.
    The cheapest among them should manage 2000 cycles.
    Notice that the 400 number was qualified with "hot environment". I am not sure just what that signifies, but I am willing to allow that even with the best of care there are environments and usage patterns that are going to reduce the lead acid number from 2000. (That is almost five and a half years, BTW, and from what I have heard that is a pretty good life with perfect care.)
    SMA SB 3000, old BP panels.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #33
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    Re: LFP or LifePo4: questions about using
    inetdog wrote: »
    Notice that the 400 number was qualified with "hot environment". I am not sure just what that signifies, but I am willing to allow that even with the best of care there are environments and usage patterns that are going to reduce the lead acid number from 2000. (That is almost five and a half years, BTW, and from what I have heard that is a pretty good life with perfect care.)

    Pretty good life with perfect care? More like expected life for cheap ones if you don't totally screw up.
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  • Mountain Don
    Mountain Don Solar Expert Posts: 494 ✭✭✭
    #34
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    Re: LFP or LifePo4: questions about using
    inetdog wrote: »
    ......qualified with "hot environment". I am not sure just what that signifies, ....

    Most of AZ, southern NM, CA deserts, parts of NV, and so on..... they spend most of the year above STC by a large amount. Definitely not a friendly environment for FLA. I guess that helps tip the scale in favor of LifePo4 in those locations.

    That's one more thing we like about being at 8800 feet. We don't have too many hours above STC.
    Northern NM, 624 watts PV, The Kid CC, GC-2 batteries @ 24 VDC, Outback VFX3524M
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  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    #35
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    Re: LFP or LifePo4: questions about using
    Cariboocoot wrote: »
    Pretty good life with perfect care? More like expected life for cheap ones if you don't totally screw up.
    Are you using the standard criterion that end of life for FLA is when the AH capacity has been reduced to only 80% of the original capacity?
    For many off-gridders, I suspect that the end of life criteria are a lot more relaxed than that, given the cost of battery replacement.
    "Honey, we need to use 20% less electricity this year, until we can afford new batteries." Or else just accept that you are going to be running down to 25% DOC for awhile instead of 20% ?
    SMA SB 3000, old BP panels.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #36
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    Re: LFP or LifePo4: questions about using
    inetdog wrote: »
    Are you using the standard criterion that end of life for FLA is when the AH capacity has been reduced to only 80% of the original capacity?
    For many off-gridders, I suspect that the end of life criteria are a lot more relaxed than that, given the cost of battery replacement.
    "Honey, we need to use 20% less electricity this year, until we can afford new batteries." Or else just accept that you are going to be running down to 25% DOC for awhile instead of 20% ?

    Running 30% DOD. 5 years so far. Zero noticeable degradation in available power.

    At 80% of original capacity a 25% DOD will still leave you above 50% SOC of the remaining capacity. You lose your "day two" reserve, but you'll probably be at 7 years life use anyway.

    People just don't listen to what I say; that's why they have problems. Setting it all up right to begin with, making sure they are charged, watching for problems that might arise, not increasing loads, etc.

    Most batteries do not die of natural causes; they are murdered. This fact gives people cause to make stupid statements like "lead-acid batteries don't work for RE" when in fact thousands of systems work without difficulty.
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #37
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    Re: LFP or LifePo4: questions about using

    How are the warranty's working for you guys ?? I see they have no warranty or some limited amount of time ( 3 months ) We started at 1,000 we're talking about, now were up to 5,6 7,000 cycles if you believe somes claims.


    http://www.batteryspace.com/warranty.aspx

    3 All Lithium Primary Cells No Warranty
    4 Trail Tech HID Head Light 3 months
    5 Single Cell Li-ion Polymer Batteries/Non-High-Power Polymer Batteries 3 months
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  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    #38
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    Re: LFP or LifePo4: questions about using
    Cariboocoot wrote: »
    Running 30% DOD. 5 years so far. Zero noticeable degradation in available power.
    I did not ask about available power, I asked about available energy. Have you done a controlled capacity test in the last year or two? (No shame if you have not, but a nice thing to know anyway.)
    Your focus is correct in that most off grid users who have non-PV charging capability will not notice a small reduction in capacity (energy) nearly as much as they would notice an increase in internal resistance (reducing available power).
    SMA SB 3000, old BP panels.
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  • Photowhit
    Photowhit Solar Expert Posts: 6,003 ✭✭✭✭✭
    #39
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    Re: LFP or LifePo4: questions about using
    Cariboocoot wrote: »
    If you only get 400 cycles from lead-acid you are doing something horribly wrong.
    The cheapest among them should manage 2000 cycles.

    I think the 400 cycles came from the article on military development article, and I think the Military specs Odyssey batteries. Also there are cycles and there are cycles. I suspect They were talking cycles to 80% DOD, which I would hazard is not what 'Coot is talking about when he says "manage 2000 cycles". I just think we're all on different pages... So on page 17 of Odyssey's manual here is a test for dual use batteries to 80% DOD, add some high temps and you could see where 400 cycles comes from;
    Attachment not found.
    od.JPG 64.5K
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
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  • Skyko
    Skyko Solar Expert Posts: 121 ✭✭✭✭✭
    #40
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    Re: LFP or LifePo4: questions about using
    Mountain Don wrote: »
    Most of AZ, southern NM, CA deserts, parts of NV, and so on..... they spend most of the year above STC by a large amount. Definitely not a friendly environment for FLA. I guess that helps tip the scale in favor of LifePo4 in those locations.

    That's one more thing we like about being at 8800 feet. We don't have too many hours above STC.

    LifePO4 hates the hot temps just as much as FLA does.
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  • Photowhit
    Photowhit Solar Expert Posts: 6,003 ✭✭✭✭✭
    #41
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    Re: LFP or LifePo4: questions about using
    Blackcherry04 wrote: »
    How are the warranty's working for you guys ?? I see they have no warranty or some limited amount of time ( 3 months ) W...

    3 All Lithium Primary Cells No Warranty
    4 Trail Tech HID Head Light 3 months
    5 Single Cell Li-ion Polymer Batteries/Non-High-Power Polymer Batteries 3 months

    For what it's worth the Balqon large system batteries do come with a 5 year prorated warranty. Not sure how large of cells Battery Space sells, but it would appear that Balgon does stand behind their product.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
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  • Mountain Don
    Mountain Don Solar Expert Posts: 494 ✭✭✭
    #42
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    Re: LFP or LifePo4: questions about using

    I was under a false impression then. So hot deserts would have no advantage as far as lifespan?
    Northern NM, 624 watts PV, The Kid CC, GC-2 batteries @ 24 VDC, Outback VFX3524M
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #43
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    Re: LFP or LifePo4: questions about using
    Photowhit wrote: »
    For what it's worth the Balqon large system batteries do come with a 5 year prorated warranty. Not sure how large of cells Battery Space sells, but it would appear that Balgon does stand behind their product.
    Wow, that looks like quite system and expensive.

    http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CB4QFjAA&url=http%3A%2F%2Fwww.balqon.com%2Fwp-content%2Fuploads%2F2013%2F07%2F39_39ES30HD_HIQAPa.pdf&ei=mncbVIKNG9eHsQTejoAY&usg=AFQjCNEhWcc4Lj-G9aWTTNLniJ9AT54Q8g&bvm=bv.75774317,d.cWc
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  • Reed
    Reed Solar Expert Posts: 55 ✭✭
    #44
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    Re: LFP or LifePo4: questions about using

    Photowit

    Checked Balqon's website and their energy storage systems come in 2.6, 9, 15, 18, 36, 52, and 72 kW-hr storage banks in 12, 24 and 48 V configurations. Systems can be connected in series or parallel to storage capacities up to 500 kW-hr and voltage range of 12 - 700 VDC

    The 9 kW-hr with BMS is $3350 and the 18 kW-hr is $6650 and 36 kW-hr is $12,650. Am sure we shall hear complaining from folks with $12K motorcycles and quads and $50K bass boats. The prices are going down.
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  • Photowhit
    Photowhit Solar Expert Posts: 6,003 ✭✭✭✭✭
    #45
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    Re: LFP or LifePo4: questions about using

    I'm not really taking sides, I know very little about LiFePo batteries, just want to pass along what little I've learned. As I pointed out in the former thread, it appears to be very expensive when compared to flooded lead acid batteries that are mass produced. When production reaches a high level I suspect/hope prices go down. That said, I admit those prices are lower than I expected, but still represent more than double similar lead acid batteries by capacity. I do see real advantages for places where energy density are at a premium.

    I can also see possible advantages where net metering is not available and cost of electric is very high. It might be that a hybrid system with a minimal LiFePo battery and good sized array, might well replace the grid in daytime hours. A small LiFePo bank could provide current for spikes to start compressors/motors where a much larger lead acid bank would be required. I was intrigued with a solar set up like this in near to me St. Louis suburb that doesn't allow net metering. I was amazed at how close to cost effective the system was, though by my calcs still more costly than the grid. We have a current person posting from Jamaica, with electric at 42 cents a Kwh. It might be possible to have a cost effective system in such a place. I may try to run the numbers this weekend. Jamaica will offer greater potential, due to having longer winter time days. Lots to work out, with panels so cheap having south east and south west facing arrays... Things to ponder.

    I didn't intend to post in this thread, I hope the original poster will not consider this any threat. I'm enjoying learning about LiFePo batteries. I hope I'm adding to the discussion rather than sending it down another track. Certainly their ability to deliver high amounts of current are one of their advantages.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
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  • PNjunction
    PNjunction Solar Expert Posts: 762 ✭✭✭
    #46
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    Re: LFP or LifePo4: questions about using
    Skyko wrote: »
    LifePO4 hates the hot temps just as much as FLA does.

    That's correct - there are parasitic reactions taking place at hot temps, which is something you don't see on the typical cycle-life specs run at a comfy 76F. :)

    Operationally, unlike lead where you want to keep them topped off or near 100% SOC, especially in hot weather, just the opposite is true for lifepo4. Normally one doesn't want to have these sitting around at 100% SOC for a *long* time, especially in hot weather, so again a conservative approach to charging up to maybe 85-90% or so helps.

    If your bms demands that you always reach 100% SOC every cycle in order to activate cell-balancing circuitry, that may not be such a great idea in hot weather.
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  • PNjunction
    PNjunction Solar Expert Posts: 762 ✭✭✭
    #47
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    Re: LFP or LifePo4: questions about using
    Photowhit wrote: »
    Not sure how large of cells Battery Space sells, but it would appear that Balgon does stand behind their product.

    For Battery Space, the largest cells would be about 200ah blue/purple GBS prismatics, which of course come in a variety of voltages, or you can build your own by paralleling cells to build capacity FIRST, and then stringing those groups of paralleled cells in series to get your voltage.

    The warning here is that they also sell a wide variety of cylindricals and other non-prismatics, either bare-naked, or with balancers, bms, and all other sorts of stuff tacked onto the top of them. Of course I chose the bare-naked cells only that were pre-strapped, with cell-links and end terminals already assembled. They are just a specialty battery place, you can also get them from Elitepowersolutions.

    When looking at prices, always compare the bare-naked cell price (or bare naked pre-built packs), compared to all the extra fluff one may want to add on top for seasoning. :)

    SAFETY - it may seem pretty simple, but the GBS cells come with removable purple cell covers for each cell. Use them. Other brands don't, and require you to build your own safety enclosure on top. For the first time experimenter, just having those covers come with the batteries can save your day, unlike others that you swear you are going to build a top-cover for when you find a round-tuit. :)
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  • PNjunction
    PNjunction Solar Expert Posts: 762 ✭✭✭
    #48
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    Re: LFP or LifePo4: questions about using
    Photowhit wrote: »
    Things to ponder.

    Most certainly. My main attraction was operating very simply in a PSOC environment. It is really mind bending to have a load do a discharge, and just have the freedom to walk away without charging if I so desired. Or if weather conditions got bad. Simplified charging - just CC to 13.8 to 14.v and stop. No eq, float, even absorb if you don't want to, etc to think about. And of course the things you mentioned.

    It is not a one-size fit all solution for sure. We can bench-race specs all day long, but once you get something like a small experimental one in your hands, (prismatic please, and NOT rc-modeling cylindricals) and do a little practical observation, these "aha moments" come more frequently, thinking of ways to take advantage of the characteristics. For many, these advantages are just plain not worth it at this time.

    I'm just standing on the shoulders of giants who have surpassed the 5 year mark, and hope to add to the pool of experience as time goes by - and so far, I'm having a lot of fun with those discoveries.
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  • creeky
    creeky Banned Posts: 31 ✭
    #49
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    Re: LFP or LifePo4: questions about using

    While the Balqon specifies an operating temp. range of -45 to 65C, I have yet to hear back about any effects on lifespan or capacity at temperature extremes.

    I did find this on an Australian site:

    "The good news is that Li* cells are only very slightly affected by cold temps, I read the other day that at about -18C, Lead-acid is down to 50% available capacity, but Li only drops by 9%." * Li = LFP.

    I include the link: https://forums.energymatters.com.au/solar-wind-gear/topic5108-10.html
    The guy talking has a LFP pack and is the system moderator.

    This is very important to me, as my batteries have gone as low as -17.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #50
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    Re: LFP or LifePo4: questions about using

    Actually your batteries probably do not go to -17C if they are in use. Ambient temperature is not the same as internal battery temperature. Keeping batteries warm is pretty easy for a set that are either being discharged or charged.

    And if the batteries do cool to ambient because they are not being used then the reduced capacity isn't relevant.
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  • Mountain Don
    Mountain Don Solar Expert Posts: 494 ✭✭✭
    #51
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    Re: LFP or LifePo4: questions about using
    Cariboocoot wrote: »
    And if the batteries do cool to ambient because they are not being used then the reduced capacity isn't relevant.

    That is a valid point. Our issues surface because of periods of no use, just a maintenance charge via the PV & CC for a few weeks, followed by a couple days of use, then weeks of no use. The batteries then do more or less assume ambient air temperature. They do lag behind because of mass which also means in spring a slow warm up. In winter I have measured very little temperature change from arriving in the dead of winter (Dec 26 or so) and leaving a week later. But our bank size works well enough for us then. Oversized some just like some users oversize a little to cover A/C summer use.
    Northern NM, 624 watts PV, The Kid CC, GC-2 batteries @ 24 VDC, Outback VFX3524M
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  • PNjunction
    PNjunction Solar Expert Posts: 762 ✭✭✭
    #52
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    Re: LFP or LifePo4: questions about using
    Cariboocoot wrote: »
    Actually your batteries probably do not go to -17C if they are in use. Ambient temperature is not the same as internal battery temperature. Keeping batteries warm is pretty easy for a set that are either being discharged or charged.

    You may find it interesting, that for powersports vehicles equipped with lifepo4 (SLI duty mind you - hundreds of temporary amperage from dinky 2-12ah batteries!) operated in extremely cold weather, to warm up the battery internally, they have to follow a different procedure than lead. That is, they turn on their lights, heated gloves, etc for a minute or two, and THEN start the bike. If it doesn't start immediately, successive attempts get stronger and stronger as the battery heats up and the bike fires. Most are used to lead where successive attempts get weaker and weaker, so this is kind of unusual to get used to.

    I hate to bring up a different application, but that is one thing to consider - you may do ok in very cold weather with small loads, as much of the trouble begins when trying to do things at 0.5C or higher. A small load (say 80A from an 800ah bank) may not suffer much.

    Caution - the above sentence is a projection about our solar application, and NOT from personal experience in extremely cold temps. Just trying to point out that others who view temperature charts about the cells, also keep in mind the current-draw specification they were made from.
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  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    #53
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    Re: LFP or LifePo4: questions about using

    Heating the battery is an old trick by applying a load to a really cold battery to get more out of it. I have used is several times as a last ditch attempt to get a car going in the depths of winter. Run the headlights for 20 seconds then try and start the car, repeat as needed. It also works to help with lead batteries.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #54
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    Re: LFP or LifePo4: questions about using

    We know about cold batteries in Canada. People have problems because the batteries get older and weaker and the engines more worn (requiring more effort to start - lower compression goes the faster they need to spin).

    Again in an active RE system the batteries should be warmer. Same principal as PNJunction measures: current going out warms up the battery and actually increases its capacity at the moment. There's probably some lab paper somewhere demonstrating the relationship between pulling 'how much' current out of 'how cold' battery of 'what capacity' for 'how long' before the action 'flips the other way' and goes from increasing capacity due to warming action to decreasing it due to draw.

    Insulate the battery area, charge and use, the will not be at ambient so no severely reduced capacity.
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  • Reed
    Reed Solar Expert Posts: 55 ✭✭
    #55
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    Re: LFP or LifePo4: questions about using

    There have been several threads over the last year that discuss much the same questions about whether one should use LFP.

    What I should like to see is a thread where folks that have used LFP batteries discuss their use: problems, successes, and equipment used (nomenclature of panels, controllers, battery bank, inverter etc). There are a lot of lurkers (and I am one) who I think should like this information.

    Folks that are happy with various forms of lead acid and naysayers could post elsewhere; as might those who wish to push Smee cells, Edison batteries and lemon batteries. They might wish to note that it takes approximately 6,171,430 lemons to provide the power of an average 4320W car battery. (0.001A/ 1mA by the average (lowest) voltage (potential difference) of a lemon (0.7V) w from Wikipedia.
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #56
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    Re: LFP or LifePo4: questions about using
    Reed wrote: »
    There have been several threads over the last year that discuss much the same questions about whether one should use LFP.

    What I should like to see is a thread where folks that have used LFP batteries discuss their use: problems, successes, and equipment used (nomenclature of panels, controllers, battery bank, inverter etc). There are a lot of lurkers (and I am one) who I think should like this information.

    Folks that are happy with various forms of lead acid and naysayers could post elsewhere; as might those who wish to push Smee cells, Edison batteries and lemon batteries. They might wish to note that it takes approximately 6,171,430 lemons to provide the power of an average 4320W car battery. (0.001A/ 1mA by the average (lowest) voltage (potential difference) of a lemon (0.7V) w from Wikipedia.
    Start your own forum and make it Exclusive to you folks. I believe there is another forum that section for Li, but might be as friendly as here.

    I talked to my local recycler about disposal, he said there is a place in Lancaster OH that doses it for a Fee, but could how much it costs to package them up and ship them.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #57
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    Re: LFP or LifePo4: questions about using

    I think people keep missing the key point that there aren't a lot of people using LiFePo4 in RE yet. At least not who have joined this forum.
    Hard to read of the experiences no one has had.

    That initial massive capital expenditure scares people right off.
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  • Reed
    Reed Solar Expert Posts: 55 ✭✭
    #58
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    Re: LFP or LifePo4: questions about using

    If the moderator (Caiboocoot) thinks it is worthwhile, then I could start a thread on this. The thread of early 2014 had three or four that were using LFP at that time. There are two of us on this thread using LFP and one that is planning to do such. PNJunction is a do-it-yourselfer and others are happier with "drop-in", which is a bit of misnomer since it still requires design/fabrication/programming. If no one else thinks it is not worthwhile, then it is a non-starter.
    Reed
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,439 admin
    #59
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    Re: LFP or LifePo4: questions about using

    You are welcome to start such a thread, and the moderators can help by removing "off topic posts" which can distract.

    Problem is that a well designed system operated well will not have much in the way of news. ... Until something breaks. Which we hope will be years in the future.

    I believe the batteries work well. ... It is the oh heck events that will kill any battery system.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Photowhit
    Photowhit Solar Expert Posts: 6,003 ✭✭✭✭✭
    #60
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    Re: LFP or LifePo4: questions about using
    Blackcherry04 wrote: »
    I talked to my local recycler about disposal, he said there is a place in Lancaster OH that doses it for a Fee, but could how much it costs to package them up and ship them.

    Just so this doesn't scare people off, I know a local chain here in Missouri who will take them and recycle them gratis.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
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  • Blackcherry04
    Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    #61
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    Re: LFP or LifePo4: questions about using
    Photowhit wrote: »
    Just so this doesn't scare people off, I know a local chain here in Missouri who will take them and recycle them gratis.
    How about a name and number. I'd like to know the shipping requirements and get that free offer in writing.
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