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  1. #1

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    AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    In case you haven't seen it.... a123 is a new lipo type. Higher capacity and FAST 5 minute recharge thanks to nano technology. Batteries are hard to get, but Dewalt has them in the new 36V tools. I haven't tested them yet, but supposed to be significantly greater capacity than normal Lipo's.

    a123 info:
    www.a123systems.com

    Dewalt info:
    http://www.dewalt.com/us/products/at...roductID=14905

    Battery packs can be found on EBay now:

    http://search.ebay.com/search/search...&fsop=1&fsoo=1

  2. #2

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Sounds interesting, anything coming out for R/C yet? 5min recharge!! And more power in a normal Li-Po, it's like saying that it's only better in everyway!!

    I sure am going to stay up to date with this stuff, if it's a 5 min recharge, that means i'll only need 1 of a pack to fly for a whole day.

    Thanks

    LeBlanc

  3. #3

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    The manufacturer is VERY tight on quality control and licensing. It will be a while before they are available in separate packaging. Web site says that power can be 100C peak and LiIon batteries are 1380W/Kg while these are rated at 3000W/Kg.

    I have one of the DeWalts on order so I can gut it and test. The biggest question is whether these are closer to LiIon or LiPo on the charging voltage.

    What amazes me is that I have posted this in a couple different places and there seems to be ZERO interest in what I see as a major technology improvement. This is as much an improvement as NiMH to LiPo along with a GROSS improvement in charge and discharge rates.

  4. #4

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    I KNOW!! Maybe they are waiting for something that they can actually buy and use... maybe who knows, maybe don't even bother coming to read..

    We'll see I sure am looking forward to further results!

  5. #5
    Taildragger726's Avatar
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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    There is interest, believe me! Just when will this new technology be available to us modelers and how will we use it !!

  6. #6
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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Very interested..... but waiting to see how they do before jumping in. Sounds good - REALLY good. [8D]

  7. #7

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Well - I should have them in a couple of days. I'm planning to gut and test them individually to see what a cell will do. I am hopeful that the voltages will be close enough to use either lion or lipo charger on them.

  8. #8

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    I'm curious about the weight of the cells and the voltage.. Are they 3.6v?

  9. #9

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    I've heard they are 4 volt cells with a slightly higher weight to power and they do not catch fire. These things are going to revolutionize a lot of things - not just RC. It's only just begun.

  10. #10

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    I've read an article somewhere, there were so many interesting things I have no idea where to start nor what to say, but I know that it did say that electrcity/batteries, is just nothing the beginning.

    I do recal that they are experiencing with a kind of battery, with a gas mixture inside under pressure.

    Really sounds interesting!

    I sure am looking to the future

  11. #11

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    I'll have picutures probably later today. I'll see what I can do about testing. I just got my ICE charger so any testing will be limited to its capacity (8 or 10A charge/discharge). I'll weigh them and such.

    I'll slow cycle one of the cells a few times then slowly ramp up the charge rate just stay safe and track the Mah and such I think the ICE will do that... We will see. I've been following these cells for a long time as well, pretty excited. I paid $155 for the pack. so assuming each cell is 3.6v there will be 10 Cells. $15.50/cell.


    More to come.

  12. #12

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Well here are some pictures. You can see the pack. Each Metal cell had a thin paperboard case that easily slides off. It protects the cells from shorting out on the case as the metal side of the case is connected to the end of the cell.

    You can see the A123 marking on the paperboard sleeve..I noticed this apears to be laser burned in. pretty neat. Each cell weighs 70grams with out the paper sleeve and 72g with it.

    The stupid dewalt pack was held together with saftey torx..of a size that sears doesn't sell..its between T10 and T15..so i busted out the dremel and slotted the heads and removed them that way. The top of the pack(as you can see in the pictures houses a hefty solid state piece of electronics. It looks to me like a built in cell balancer for charging and also it has a thermo couple that wsa taped to the pack(the thin black "wire" with the amber tape on it. The jig that holdes the cells in the pack connects to the "balancer" with some plugs..pretty nice. This could possibly be of some use.

    I'll see what time I have to do testing for capacity and such. For now I'll be treating them as Li-Ion as that is what I believe them to be.

    Untill then..
    Gigaah
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  13. #13

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Well I've charged and discharged them 3 times.

    Charge 2.2A Discharge 2.2A 2400MAh ...cell not above room temp after charge
    Charge 5A Discharge 10A 2200MAh ...Cells slightly warm
    Charge 8A Discharge 10A 2250MAh ...Cells definatly got warm (no temp sensor as you can tell)


    I'm not sure how warm to the touch 90-95F is that the ICE manual called the max temp range but I suspect I might have reached that, perhaps exceeded it at 8A charge...can't really say as I don't exactly know how warm 95F is by touch. I'll have to order a temp sensor. I do notice the discharge voltage according to the ICE never really sits at 3.6V under load Its always 3.4 and well under most of the time. I'm a bit concerned about that and the temp at 8A but I don't charge many lipo but I think it should hold voltage better than that right? Maybe someone has an explanation? I also noticed the voltage spiked to 4.4 after the constant current cut off on the last charge...its the only cut off I saw..any insight is welcome.

    Gigaah

  14. #14

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Heres some information about these batteries. http://site.buya123systems.com/ANR26650M1specs.pdf

  15. #15

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    your awsome. thats a great link. Now I just have to decide if these cells are any good because of the odd voltage.

    So I think that sheet basicly is saying that a standard Lipo charge isn't proper for the cell as it runs different voltage..right? CCCV to 3.6v? But it does mention charge/discharge to 4.2v at 0c? I'm kinda confused.

    BTW it is cheaper to get the cells in the dewalt packs yet.

  16. #16

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Bummer - my cells are not here yet!

    On the web site for A123, they show a max charge of about 4v and a max discharge of 2v per cell (listed in the temperature performance chart and the charge/discharge cyle chart). The charts definately show the voltage spike that you mentioned. BTW: the charts are on the performance and safety pages of the web site.

    Given the 2200 mah that you have measured, the web site indicates that the cell should be capable of 100C burst, 80C surge and 30C continuous..... 220AMPS burst, 160AMPS surge and 66Amps continuous, per cell. If you are testing with standard lion settings, I think that you might get a bit more power using a manual voltage cutoff. Althought the charge cycle chart is a bit difficult to see, it appears that a max of 3.5v and a min of 2v is normal. But there is not much capacity below 2.5v. The chart also shows a peak of 40 deg C.(104F) for the tested charge/discharge that is similar to your tests. I noticed that the voltage starts moving up quickly near the end of the charging. I think that the mfg are cutting the charge off at 4v.

    The difference is that even with extreme temperature spikes that would kill normal lithium cells, the carbon encapsulation prevents cell damage.

    For Weight comparison - a Thunderpower 2S 2100 (20C) pack is listed on hobby-lobby at 3.2oz. That gives 44.8 grams for the cell and half the package and connector. I have no idea of the package and connector weight... maybe 8-12 grams???? That would give an estimate of 33 grams/cell versus the 70g that you measured. This is somewhat disappointing. However, the website shows a123 cell to be twice the energy density of Lion cells.... They don't really compare them to lipo cells. They show weight to discharge at 1500w as .9lbs (14.4oz). At 70g, that is 6 cells. A Polyquest20 pack (3S 3700) weighs 10.4 oz to output the same power.

    To that end - these seem to be safer cells, but a bit heavier than Li Poly cells.

  17. #17

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Thanks for the pictures and the bold attitude on testing these for the community! Here's a link to the A123Systems developer kits(be sure to click on the 'Specs' link when you get there):

    http://www.buya123systems.com/prdeki.html


  18. #18

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Here's some info why these lithium phosphate li-ions are so special:

    "Lithium Phosphate
    Recent developments have produced a range of new environmentally friendly cathode active materials based on Lithiated transition metal phosphates for Lithium-ion applications.

    Phosphate based technology possesses superior thermal and chemical stability which provides better safety characteristics than those of Lithium-ion technology made with other cathode materials. Lithium phosphate cells are incombustible in the event of mishandling during charge or discharge, they are more stable under overcharge or short circuit conditions and they can withstand high temperatures without decomposing. When abuse does occur, the phosphate based cathode material will not burn and is not prone to thermal runaway.

    The operating performance of the cell can be "tuned" by changing the identity of the transition metal. This allows the voltage as well as the specific capacity of these active materials to be regulated. Cell voltages in the range 2.1 to 5 Volts are possible.

    Phosphates significantly reduce the drawbacks of the Cobalt chemistry, particularly the cost, safety and environmental characteristics. Once more the trade off is a reduction of 14% in energy density, but higher energy variants are being explored.

    Due to the superior safety characteristics of phosphates over current Lithium-ion Cobalt cells, batteries may be designed using larger cells and potentially with a reduced reliance upon additional safety devices."

    http://www.mpoweruk.com/lithiumS.htm

    In the words of the Mad Scientist, "we blow things up so you don't have to!" :-)

  19. #19

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Yeah, I saw those specs. After reviewing the specs and stability of the cell I've decided to..and have been cylcing this cell.

    I've been charging it as li-ion (to 4.1v) CCCV. It only gets a bit warm right at the end when the voltage spikes to 4.4-4.5. It doesn't spike above 4.2 if I charge at 4.6A..but I'm just working this cell out and charging at my full capacity of 8A. It never gets hot..just pretty warm, and it only gets "pretty warm" for a few seconds.

    though I'm still testing here what I have so far. charging cccv to 4.1v and discharging to 2.5v(as low as I can go..though the specs say they go lower). The discharge graph on the site seems to be about right..so I've not been recording this as I have no real way of doing it...suffice it to say at 10A discharge I'm usually getting 3.125V after draining about 500MaH and most before that is around 3.2v

    Capacity after discharge of 10A, after charge of 8A
    2200
    2250
    2331
    2325
    2345
    2336
    2340
    2350


    I'm just looking to see how this cell is handleing the charge i can give it. More results to come..if there is anything else we are interested I can check let me know.


    PS. I'm not stupid either. I'm charging this thing in a safe area in a fireproof box!!!

  20. #20

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    ORIGINAL: duanes

    Bummer - my cells are not here yet!

    On the web site for A123, they show a max charge of about 4v and a max discharge of 2v per cell (listed in the temperature performance chart and the charge/discharge cyle chart). The charts definately show the voltage spike that you mentioned. BTW: the charts are on the performance and safety pages of the web site.

    Given the 2200 mah that you have measured, the web site indicates that the cell should be capable of 100C burst, 80C surge and 30C continuous..... 220AMPS burst, 160AMPS surge and 66Amps continuous, per cell. If you are testing with standard lion settings, I think that you might get a bit more power using a manual voltage cutoff. Althought the charge cycle chart is a bit difficult to see, it appears that a max of 3.5v and a min of 2v is normal. But there is not much capacity below 2.5v. The chart also shows a peak of 40 deg C.(104F) for the tested charge/discharge that is similar to your tests. I noticed that the voltage starts moving up quickly near the end of the charging. I think that the mfg are cutting the charge off at 4v.

    The difference is that even with extreme temperature spikes that would kill normal lithium cells, the carbon encapsulation prevents cell damage.

    For Weight comparison - a Thunderpower 2S 2100 (20C) pack is listed on hobby-lobby at 3.2oz. That gives 44.8 grams for the cell and half the package and connector. I have no idea of the package and connector weight... maybe 8-12 grams???? That would give an estimate of 33 grams/cell versus the 70g that you measured. This is somewhat disappointing. However, the website shows a123 cell to be twice the energy density of Lion cells.... They don't really compare them to lipo cells. They show weight to discharge at 1500w as .9lbs (14.4oz). At 70g, that is 6 cells. A Polyquest20 pack (3S 3700) weighs 10.4 oz to output the same power.

    To that end - these seem to be safer cells, but a bit heavier than Li Poly cells.
    Thats pretty much exactly correct with the comparision of dewalts lithium batteries and existing lithium polymers. Existing lithium polymer batteries are around 160 wh/kg, and dewalt is around 100 wh/kg along with all the other lithium power tool batteries. I think the difference that really sets the two apart is the cycle life you can get at high rates of discharge. The dewalt seems to offer many cycles with a good amount of discharge capability but still suffers from voltage loss pretty substantially as discharge rates increase. The advantage the higher quality li-po packs have over these dewalts isn't only the amount of power per weight, its also the ability to hold a high rate of voltage even at high rates of discharge. Its basically a trade off of having the best of the two as far as i can see, the dewalts are for someone who doesn't want to worry about cycle life and doesn't mind moderate power levels. Lithium polymer packs are for someone who is looking for the most energy per given weight being used at high discharge rates who isn't concerned with getting only 100-200 cycles.

  21. #21

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Yeah, the voltage isn't that of a lipo. It says nom voltage of 3.3. Running voltage in the 3.2-3.1 range.

    As I'm cycling this cell my Capacity is going up steadily. My most recent discharge came up with 2400MAh

  22. #22

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    I think these cells will fill a niche in my RC CAR. High discharge rate, long life, much safer, durable, and still lighter than NiMh.

  23. #23

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Due to the ability to pulse discharge, I can see their use in applications where lipo's won't work and Nicad are still heavily used. F5B comes to mind. During launch, these motors can draw 200 amps, but only run 30 seconds to pull the plane nearly out of sight. These cells offer considerable weight/capacity improvement over nicad in that aspect.

    In comparison to NiMH, there is some advantage to a123 in terms of weight, however, all of the nimh cells listed on hobby-lobby have max discharges in the 10-20c range.(with some on the order of 5c)

    .... Has anyone been able to determine the operation of the electronics package in the dewalt power pack? Is it a charger, balancer, other???

  24. #24

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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    I'm looking at the eletronics now. I can't for 100% certain say what it is but ..

    It has plugs that connect to the battery jig the cells were in. This is DEFINATLY part of the cell balacing. perhaps discharge protection cell balance as well. It does have a thermocouple on the unit, naturally for cut off due to over heat. I don't have a charging base to check thing out. I suspect the charger is may only be a Constant voltage supply. The unit in the battery is pretty substantial and heavy.

    There is still a substatial voltage advantage over NiMh. Even at 20C They will probably hold 2.5v(speculating on the 40A discharge graph provided by a123 at 40A/2.6v).

    here is a graph of the "Best NiMh on the market" 4300Mah.
    http://www.cheapbatterypacks.com/cel...nvid=ELITE4300

    1.25-1.2v for half of its capacity at 30Amps. 66.87g each. Say you run 7.2v pack in a car. 6 cells x 66.87 = 401.2G

    4300Mah/401grams and 7.5-7.2V for half of its capacity...then down hill from there.

    here is the graph for the A123
    http://site.buya123systems.com/ANR26650M1specs.pdf

    We'd need 3s2p and get 4600MAh. So you effectivly be pulling 15A from each P pack at 30A draw getting 8.7v for about 85% of the packs capacity and a weight of 420Grams. you could pull 80Amps and still get 7.5v for 85% of the capacity. Your looking at roughly the same weight. better voltage and better voltage curve over the discharge vs NiMh.

    I don't know how the voltage of other cells vary by load but these seem to change quite a lot 2.5v at 40A and around 3.15 at 10A. That is my biggest issue but my cars speed controller will support 9.6v. so no matter the load I'll never exceed 9.9v really under any load so it'll work ok, I'm just not thrilled with it. I was hoping due to the cells C rating it would hold voltage better and I expected them to be CCCV to 4.1v like li-ion and not 3.6v CCCV with a real running max voltage of like 3.2-3.15

  25. #25
    Moderator Matt Kirsch's Avatar
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    RE: AWESOME- Found Source for NEW a123 Lipo Nano Chemistry Batteries

    Moved this to "power sources" and left a link in the original forum.


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