Malkoff
Results 1 to 24 of 24

Thread: charging lifepo4 batteries.

  1. #1

    Default charging lifepo4 batteries.

    i have 3 40160s 3.2v 16ah batteries and want to hook up a charger to them.
    as they are 16ah with 1cc charge current recommend i was looking for a charger that could fit my needs been searching around and was looking at http://factory.dhgate.com/charger/6....p44623238.html although i would have to worry about overcharge protection i was wondering if i needed a Protection board on the battery pack. this will be used to drive sst-90. not sure if i should just use 2 cells or in battery pack but as charging goes i've not seen a higher amp charger. i've seen a few 9.6v charger and few 3.2v ones but they are very low amps and would take more then 4 hours for one cell. to charge. any suggestions?

  2. #2
    Flashaholic sunny_nites's Avatar
    Join Date
    Mar 2010
    Location
    USA
    Posts
    191

    Default Re: charging lifepo4 batteries.

    You are on the cutting edge here. Doesn't appear to be a lot of experience with Lifepo4s around. I have used them to a degree ie. aa size with standard charger that came with the set of batteries and don't have much experience other than to say they appear to run as specified.

    Also, the link you specified appears to be suspect. My link detector lit up when I tried to access it.
    So many LEDs, so little time...

  3. #3
    BVH's Avatar
    Join Date
    Sep 2004
    Location
    CentCalCoast
    Posts
    5,869

    Default Re: charging lifepo4 batteries.

    This will do any chemistry on the market and at any rate up to 40 Amps with the right power supply.

    http://www.revolectrix.com/pl8_description_tab.htm
    WWII 60" Anti Aircraft Carbon Arc (Sold), Short Arcs: 1.6KW NightSun, 1KW VSS-3A, .8KW TrakkaBeam, 600 Watt M-134 Gun Light, 500 Watt X-500-14s, 500 Watt Starburst, 300 Watt Locators, Megaray, 150 Watt Set Beam & Communicator, Maxabeam Gen3, LarryK14@52V

  4. #4

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by BVH View Post
    This will do any chemistry on the market and at any rate up to 40 Amps with the right power supply.

    http://www.revolectrix.com/pl8_description_tab.htm
    WOW! BVH thats one heck of a hobby charger there.

  5. #5
    BVH's Avatar
    Join Date
    Sep 2004
    Location
    CentCalCoast
    Posts
    5,869

    Default Re: charging lifepo4 batteries.

    It's a fantastic charger but to get all that power out of it with Lithium batteries they must have balance taps and it must be balance charged. It's kinda geared for the Prismatic packs that the RC people use. I have a bunch of them for my flashlights and power supplies so I use it all the time. They just came out with its' little sister, a PL6 that will do 30 Amps, IIRC.
    WWII 60" Anti Aircraft Carbon Arc (Sold), Short Arcs: 1.6KW NightSun, 1KW VSS-3A, .8KW TrakkaBeam, 600 Watt M-134 Gun Light, 500 Watt X-500-14s, 500 Watt Starburst, 300 Watt Locators, Megaray, 150 Watt Set Beam & Communicator, Maxabeam Gen3, LarryK14@52V

  6. #6

    Default Re: charging lifepo4 batteries.

    The iCharger 208B will charge at 20A, for about $150 shipped.

  7. #7
    Banned
    Join Date
    Dec 2011
    Location
    Northern Europe
    Posts
    879

    Default Re: charging lifepo4 batteries.

    Or Turnigy MEGA 400W V2 if you're on budget - it supports up to 20 amps as well, but it's almost 2 times cheaper (at ~$80 shipped).
    Note that you'll need hell of a power supply to power any of those chargers - a good option would be modern ATX12V PC PSU.

  8. #8
    Enlightened abhi555's Avatar
    Join Date
    May 2006
    Location
    Idaho
    Posts
    31

    Default Re: charging lifepo4 batteries.

    Anybody has experience with this cheap charger? Claims to be capable of charging various chemistry (NiMH, LiPo, Li-ion)
    http://www.ebay.com/itm/4-AAA-HR03-1600mAh-NiMH-1-2V-Rechargeable-Battery-1412W-Multi-LiFePO4-Charger-US-/270896406337?pt=LH_DefaultDomain_0&hash=item3f12af 1f41#ht_3372wt_1396




  9. #9
    Flashaholic* LEDAdd1ct's Avatar
    Join Date
    Jul 2007
    Location
    Hudson Valley
    Posts
    3,145

    Default Re: charging lifepo4 batteries.

    I would stay far away. Looks like an accident waiting to happen.
    "...and the diode multiplied and grew in brightness. And God saw that it was good."

  10. #10
    Banned
    Join Date
    Dec 2011
    Location
    Northern Europe
    Posts
    879

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by LEDAdd1ct View Post
    I would stay far away. Looks like an accident waiting to happen.
    Accidents never happen with proper LiFePO4's (like A123), they are safe chemistry.
    But it could kill the cells or degrade them hugely...

  11. #11
    Flashaholic
    Join Date
    Aug 2001
    Location
    Winnipeg,MB,Canada
    Posts
    155

    Default Re: charging lifepo4 batteries.

    I charge my home made 2s LiFePO4 Airsoft packs using a iCharger 106B (http://www.jun-si.com/EnProductShow.asp?ID=89) powered by a RC hobby power supply. Slow charging is suggested to be 1.5A and fast charging at 5A from the a123 systems specifications sheet for my 18650 cells. (so fast charge is done in like 5-6min). I do balance charge them but I just run them till the gun starts slowing down then swap em out. (so no low voltage protection) If you do run them too low you will harm em a little but they wont go boom - you will just loose some capacity. I do also have some Tenergy brand RCR123A LiFePO4 cells I am testing out in some lights but they came with their own charger that outputs 250ma so I just use that for them and when they start to go dim swap em out.

    For a huge 40160 cell though you could likely dump up to 80A into them to speed up your charging time before you start to damage them. Good luck pulling that off without some sort of custom solution. You could try a higher end hobby charger like an iCharger 306B (http://www.jun-si.com/EnProductShow.asp?ID=100) but that will only get you up to 30A max and you would still need to find a REALLY beefy power supply (or a few hooked together) to get that going... The nice thing about these hobby chargers however is there is no need to worry about overcharging as they will stop when the cell is full and you can do more then one cell at a time (6 or more depending on the model) if you wire it up correctly to the balancing connector.

    Just a warning - once you start going up to these current levels you need to make sure you are using the correct gauge wire and quality connectors or things can start melting. Also LiFePO4 are not much of a explosion or vent/fire risk if abused but if you manage to short them they will get VERY hot and what ever you short them with will weld it self in place and get white hot. So even though the batteries themselves are safer - they still carry their own risks to be aware of.

    A good resource for more info about this kinda thing can be found over @ http://www.rcgroups.com/batteries-and-chargers-129/ as they have been using LiFePO4 for a while now.

    Oh and that 1412 charger looks like junk - I have never seen it before but I would not take the risk.

  12. #12
    Flashaholic* LEDAdd1ct's Avatar
    Join Date
    Jul 2007
    Location
    Hudson Valley
    Posts
    3,145

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by Shadowww View Post
    Accidents never happen with proper LiFePO4's (like A123), they are safe chemistry.
    But it could kill the cells or degrade them hugely...
    No, no, no—that wasn't a criticism leveraged at LiFePO4 cells, that was a criticism directed towards the "will charge everything and do your laundry" cradle charger posted above.
    "...and the diode multiplied and grew in brightness. And God saw that it was good."

  13. #13
    Banned
    Join Date
    Dec 2011
    Location
    Northern Europe
    Posts
    879

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by OrBy View Post
    For a huge 40160 cell though you could likely dump up to 80A into them to speed up your charging time before you start to damage them. Good luck pulling that off without some sort of custom solution. You could try a higher end hobby charger like an iCharger 306B (http://www.jun-si.com/EnProductShow.asp?ID=100) but that will only get you up to 30A max and you would still need to find a REALLY beefy power supply (or a few hooked together) to get that going... The nice thing about these hobby chargers however is there is no need to worry about overcharging as they will stop when the cell is full and you can do more then one cell at a time (6 or more depending on the model) if you wire it up correctly to the balancing connector.
    Not all LiFePO4 cells support 5C charge, in fact, I've only seen A123 ones that do. Most LiFePO4's have recommended charge current of 0.7C and maximal charge current of 1C. So I wouldn't pump any more than 20 amps into that 16 Ah cell, in fact, if I had one myself I'd more likely charge it at 10A or so.
    Quote Originally Posted by LEDAdd1ct View Post
    No, no, no—that wasn't a criticism leveraged at LiFePO4 cells, that was a criticism directed towards the "will charge everything and do your laundry" cradle charger posted above.
    Ah, I see. sorry

  14. #14
    Flashaholic
    Join Date
    Aug 2001
    Location
    Winnipeg,MB,Canada
    Posts
    155

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by Shadowww View Post
    Not all LiFePO4 cells support 5C charge, in fact, I've only seen A123 ones that do. Most LiFePO4's have recommended charge current of 0.7C and maximal charge current of 1C. So I wouldn't pump any more than 20 amps into that 16 Ah cell, in fact, if I had one myself I'd more likely charge it at 10A or so.
    Valid point there - I have only seen spec sheets for the a123's system's cells. If that's the case even a smaller hobby charger with power supply would suit these just fine then. A 15A-20A supply (for a bit of leeway) and something like my 106B could speed up his charging and do all 3 of his cells at once if wired up to the balance connector. If you shop around you could likely find that all for under $100.

  15. #15
    Flashaholic*
    Join Date
    Mar 2002
    Location
    San Diego
    Posts
    2,285

    Default Re: charging lifepo4 batteries.

    The Headway 16Ah LiFePo4 40160's have been discontinued according to Headway Headquarters. The largest now offered are 15Ah 40152's. I have considered charging 4S multiple blocks of 40152's using (a) cell to cell balancing connectors designed for 20Ah lower discharge / charge rated prismatic battery packs. I would use one or more CC/CV/pulse 3 cycle stock charger that are available in fixed at 4S, 8S, 12S, 16S, 20S, 24S, 28S and 32S sizes. Here's a link to the balancers which are not cheap at about $8.95 @.

    http://elitepowersolutions.com/produ...7588ee6768108b

    Here is data covering LIFEPO4 chargers sold by the same company.

    http://elitepowersolutions.com/produ...ex.php?cPath=9

    I'm considering building an ebike powered by a nominal 84V with 28S 40152 cells. I'd spread the cells around the bike in a 12S bundle plus a 16S bundle. I'd charge the two bundles separately with TSL36-6 and TSL48-6 Chargers, respectively.

    I'd depend upon a TBD low voltage cutoff for the 28S power source and be willing to replace bad cells as they occur. My useage and willingness to measure discharge current makes the use of a BMS problematic.
    Anything worth illuminating is worth illuminating to excess.

  16. #16
    Flashaholic* VegasF6's Avatar
    Join Date
    Dec 2007
    Location
    Las Vegas
    Posts
    1,445

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by Shadowww View Post
    Accidents never happen with proper LiFePO4's (like A123), they are safe chemistry.
    But it could kill the cells or degrade them hugely...
    They are a safER chemistry than some. All batteries including A123 are subject to failure.
    Subjected to overcharging or overheating A123 batteries absolutely will explosively decompress.

  17. #17
    Banned
    Join Date
    Dec 2011
    Location
    Northern Europe
    Posts
    879

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by VegasF6 View Post
    They are a safER chemistry than some. All batteries including A123 are subject to failure. Subjected to overcharging or overheating A123 batteries absolutely will explosively decompress.
    Uhm, how high overcharge are we talking about? I've once overcharged pair of my A123 18650's to 4.2V (instead of normal 3.6V) when I left my charger on Li-Ion setting before putting them in, but they didn't exploded, and, in fact, still are going perfectly.

  18. #18
    Flashaholic* VegasF6's Avatar
    Join Date
    Dec 2007
    Location
    Las Vegas
    Posts
    1,445

    Default Re: charging lifepo4 batteries.

    Yes, I guess it would take more than that as I have read of other people doing the same thing charging to 4.2 though that's still no guarentee of safety. I would imagine charge current and temperature would be a factor in those cases. Simply google A123 fire and Chevy Volt fire, check the RC forums etc. The results aren't the same as with a lithium cobalt chemistry battery but pump enough energy into a battery and it will pop. A hobby charger or automotive environment are capable of that energy. I don't think it's correct to make statements like "accidents never happen" when referring to these cells.

  19. #19
    Flashaholic
    Join Date
    Aug 2001
    Location
    Winnipeg,MB,Canada
    Posts
    155

    Default Re: charging lifepo4 batteries.

    I did a google search like you said VegasF6 - all I got was links on how when crushed or abused A123 System cells do nothing (not even smoke). But when they are shorted - they do cause fires because what ever shorts them gets so hot it ignites. Like with all the Prius/Volt and other EV fires in the news the cells are not causing the fires - it's improperly made cooling systems or physical braces causing the fires after shorting the cells. I think that's kinda like blaming the gas for a fire when it was the match that lit it or a gun hurting some one and not the person pulling the trigger. Now I am not saying they could never have an issue but they are the most stable cells I have ever used/abused.

  20. #20
    BVH's Avatar
    Join Date
    Sep 2004
    Location
    CentCalCoast
    Posts
    5,869

    Default Re: charging lifepo4 batteries.

    I once had 10S Power Tubes filled with DeWalt A123's. I paralleled 5 of them for about 11 AH to run my 28 Volt, 16 Amp Locator - so a 1.5C load. I did not run the light anywhere near the time required to deplete the cells, yet a few moments after shut down, a couple of the cells "poofed/vented" without flames, of course. I was surprised with such a small load.
    WWII 60" Anti Aircraft Carbon Arc (Sold), Short Arcs: 1.6KW NightSun, 1KW VSS-3A, .8KW TrakkaBeam, 600 Watt M-134 Gun Light, 500 Watt X-500-14s, 500 Watt Starburst, 300 Watt Locators, Megaray, 150 Watt Set Beam & Communicator, Maxabeam Gen3, LarryK14@52V

  21. #21
    Flashaholic* VegasF6's Avatar
    Join Date
    Dec 2007
    Location
    Las Vegas
    Posts
    1,445

    Default Re: charging lifepo4 batteries.

    I wasn't specifically talking about crushing, but certainly the very first link you found would have been this backhoe crush test. There certainly was smoke. The next prominent link was the results of a disassembled A123 from an RC airplane. Hard to say what happened there. The next link I found was a investigation for a Prius fire containing A123 cells that caught fire.

    LifePO4 and specifically A123 cells do not vent with flame as others, I never said they do. That's why they are safER. But they can have the same dangerous chemical reaction as other cells and once it's started there is no putting it out. The energy from this reaction must go somewhere. The battery is a steel can. It will build pressure and explode. Luckily there are pressure vents as a safety precaution. Unfortunately they don't do much good when the battery is in a liquid tight tube with an led at one end.

    I am not going to spend any more time with this, I will only point out one more time, it is incorrect to make a blanket statement that there is no possibility of accidents with an A123 cell. There is ALWAYS the possibility of accidents. Instead, it's up to the well informed consumer to weigh the pros and cons of each system and make his own choice.

  22. #22
    Flashaholic
    Join Date
    Aug 2001
    Location
    Winnipeg,MB,Canada
    Posts
    155

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by VegasF6 View Post
    I wasn't specifically talking about crushing, but certainly the very first link you found would have been this backhoe crush test. There certainly was smoke.
    Nope - the smoke you see is the LG Chem cell (white) they crushed first. If you fast forward to the 0:55 second mark where they crush not one but two A123 system cells (yellow) - they do nothing...

    Quote Originally Posted by VegasF6 View Post
    The next prominent link was the results of a disassembled A123 from an RC airplane. Hard to say what happened there.
    I can't quite tell but that looks like another LG cell to be honest (I could very well be wrong though) and there is really no burn or smoke marks on any of that debris. It almost looks like it was just shredded - I am trying to find more info on that one before I comment further.

    Quote Originally Posted by VegasF6 View Post
    The next link I found was a investigation for a Prius fire containing A123 cells that caught fire.
    "There is no indication that this incident was the result of a shorted or spontaneously ruptured cell. The manufacturer’s tests show that an internally shorted cell will not generate enough heat—in and of itself—to rupture the cell." Nope - not the batteries fault. It was an assembly issue with some bad bolts and poor design choices/practices.

    Quote Originally Posted by VegasF6 View Post
    LifePO4 and specifically A123 cells do not vent with flame as others, I never said they do. That's why they are safER.
    We are on the same page here.

    Quote Originally Posted by VegasF6 View Post
    But they can have the same dangerous chemical reaction as other cells and once it's started there is no putting it out.
    This is where we are not on the same page. The discharge and charge of a LiFePO4 cell is not really exothermic so there is little to no chance of a run away situation as is found with more common LiCoO2 or LiPo cells. If you really beat on them - they may vent a bit - but when you stop - they do as well. But if you toss em into a fire, yeah they will burn. They would be magic if they didn't.

    Quote Originally Posted by VegasF6 View Post
    The energy from this reaction must go somewhere. The battery is a steel can. It will build pressure and explode. Luckily there are pressure vents as a safety precaution. Unfortunately they don't do much good when the battery is in a liquid tight tube with an led at one end.
    I kinda get this for other chemistry's but since LiFePO4 vent so little and are non-exothermic I think this is a non-issue.

    Quote Originally Posted by VegasF6 View Post
    I am not going to spend any more time with this, I will only point out one more time, it is incorrect to make a blanket statement that there is no possibility of accidents with an A123 cell. There is ALWAYS the possibility of accidents. Instead, it's up to the well informed consumer to weigh the pros and cons of each system and make his own choice.
    I am on board with that statement - something could always go wrong so it never hurts to be cautious.

    I also apologize to Themaskedwolf for the thread jack. Back to your regularly scheduled charger discussion.

  23. #23
    Flashaholic* VegasF6's Avatar
    Join Date
    Dec 2007
    Location
    Las Vegas
    Posts
    1,445

    Default Re: charging lifepo4 batteries.

    Turn up the volume in the video. He clearly states the first cell crushed, the white one, is the A123. Pause the video at :55 seconds. You can clearly see the words "LG Chem" on the brown wrapper of the two parallel cells.

  24. #24
    *Flashaholic*
    Join Date
    Dec 2003
    Location
    USA
    Posts
    8,142

    Default Re: charging lifepo4 batteries.

    Quote Originally Posted by BVH View Post
    This will do any chemistry on the market and at any rate up to 40 Amps with the right power supply.

    http://www.revolectrix.com/pl8_description_tab.htm
    that's my charger....

    on another topic... doing research on LiFePO4 fires.
    would appreciate any hard data on LiFePO4 fires.

    please PM or email if you cannot post info

    PowerLab 8 (v2) Charger

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •