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Thread: Powerex 2700mAH AA / 1000mAH AAA testing results

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    Default Powerex 2700mAH AA / 1000mAH AAA testing results

    I have been testing Powerex 2700 mAH AA and Powerex 1000mAH AAA cells all week. Decided to do a forming charge at 200mA on the 2700's and a 80mA forming charge on the 1000's. First, what I used to test them.

    Cadex 7400ER battery analyzer
    LaCrosse BC900 battery analyzer
    Maha MH-C401FS charger (AAA)
    ZTS battery tester
    Fluke 179 True RMS multi-meter

    First the Powerex 2700mAH AA NiMH cells

    Forming charge of 200mA was performed by the LaCrosse BC900 battery analyzer Version 32

    Cadex 7400ER battery analyzer
    0.2C charge and 0.2C discharge rate (540mA) Two cycles
    0.92V voltage cut-off
    97 to 99% on twelve batteries (2619mAH to 2673mAH)

    Loaded 8 of them in series for a 9.6V 2700mAH pack with 0.2C charge/discharge and 1.0V cut-off two cycles
    94% (2538mAH)

    Tested at 1 amp charge 1.75 amp discharge 1.0V cut-off two cycles (four batteries tested)
    93 to 94% (2511mAH to 2538mAH)

    The reason for the odd 1.75 amp discharge rate is to see how they would perform when loaded down with my MillerMods U bin L1P helmet light. An hour twenty minutes of runtime rocks!

    Testing with BC900 battery analyzer 1000mA charge and 500mA discharge 0.9V cut-off

    2.81 to 2.91 Ah with all twelve batteries tested.


    Powerex 1000mAH AAA cell testing (four cells)
    Two cells formed on Cadex at 80mA charge and two cells formed at 200mA on a Maha MH 401FS

    0.2C charge/discharge rate (200mA) two cycles
    97 to 99% (970 to 990mAH)

    0.5C charge (500mA) 1.3C discharge (1.3 amps) 0.92V cut-off two cycles
    91 to 93% (910 to 930mAH)

    Oddball rate due to testing for a Peak Baltic Super Ultra Power AAA Luxeon flashlight to determine runtime.

    0.5C charge (500mA) 1.0C discharge (1 amp) 1.0V discharge rate two batteries in series (2.4V) Two batteries that gave equal 92% rate at 1.3 amp discharge were chosen since they were balanced.

    93% (930mAH)

    Reason for testing in a series pair is to check estimated runtime for a Peak Baltic Super Ultra Power 2xAAA Luxeon flashlight.

    Overall, the Powerex 2700mAH AA cells have the highest capacity I've ever seen. Very impressive that they hold up under the 1.75 amp discharge testing and do fine with 8 of them in series (upcoming Quad XR-E Mag) The BC900 testing was done after the 8 in series testing to see how far out of balance they became (2.84 to 2.91 Ah with the 8 cells)

    What really, really impressed me was the Powerex 1000mAH AAA cells. My guessimate was 750mAH at 1.3 amp discharge but they grunted out at least 910mAH. Having them hold 940mAH at a 1C discharge with two in series was icing on the cake.

    Since I only had two Cadex channels available at the time, I went with testing how well the Maha MH 401FS forms them at C/5. The Maha formed batteries actually outperformed the Cadex formed batteries at C/13 The sample size was way to small but the rest of the guys at work saw my results and went with the Maha.

    There you go... my first major battery testing. Can't hold a candle to SilverFox but I figured somebody might find my results interesting.

    EDIT: The Powerex 1000's were discharged at 1.3 amps (C1.3) and not 1.25 amps. Was recharging one of the cells and noticed the battery label stated 1.3 amps.

    ADDED 21 October
    One of the guys at work took two of his Powerex 1000mA AAA batteries and connected them to the Cadex to try something different. He ran them at a 80mA charge/condition/200mA discharge rate for two cycles and after 56 hours (and still recharging) his results were 98% and 100% on one battery and 99% and 97% on the second battery.

    This is the long slow charge with termination at 1.53V the Cadex performs. I am not aware it will allow you to dumb charge the battery as I have check the many functions it performs in the last few months.

    Checked two of my AAA batteries in the BC-900 that were rated 97 and 99% on the Cadex. They returned 983mAH and 1039mAH with a 200mA charge (C/5) and 100mA discharge (C/10) rates. Although the BC-900 reads slightly high, it does point out which battery is the strongest so I can keep an eye on battery balance across packs.

    My co-workers results with four 1000mA Powerex cells on the Cadex 7400ER 80mA charge/recondition/200mA discharge are 97%, 99%, 99% and 100% so after 8 batteries tested, they all read 97 to 100% with about a 99% average across 8 cells.
    Last edited by BentHeadTX; 10-20-2006 at 10:58 PM.
    Peak Pacific AAA UP brass (EDC) E01 (keys), Peaks, Arcs, Fenix, Q5 Aspheric HA-III Mag etc.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Thanks for the test! I use a Pro Former for forming my cells and packs. Wondering how the BC900 worked at 200ma which is less than .1C for a 2.7Ah cell? Did you time it for x amount of hours? It didn't terminate?

    I'm glad that you did a mind refresh on the point that BC900 capacity test are several hundred millamps higher than most other means of testing!

    I just ordered some PowerEx 1000mAh AAA the other day! I need not test them now!!
    Bill

    I'm a retired mechanic not a electronic/electrical engineer!

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by wptski
    Wondering how the BC900 worked at 200ma which is less than .1C for a 2.7Ah cell? Did you time it for x amount of hours? It didn't terminate?
    My BC900 terminated at 1.41 VDC on each cell, it has never had any problems charging at such a low level (I got lucky!) However, it would charge for around 20 minutes at 0.2C when I hooked it up to the Cadex. The ZTS tester indicated a full charge after coming off the BC900 so I proclaimed it good enough.

    Yeah, I have noticed that the results tend to be about 5 to 6% higher than the Cadex when I get the cutoff at 0.92V (won't do 0.90V) Not bad considering the Cadex costs over 80 times what a BC900 does, not bad at all. The BC900 agrees with the Cadex when it comes to cells capacity relative to each other. I plan on getting another LaCrosse so I can condition 8 cells at once for my LuxV and Quad XR-E Mag mods.

    The Powerex 1000's are the most impressive batteries I have tested, I can beat on them at 1.3C and they handle it without a wimper. I figured Sanyo came out with 1000mAH cells that might be 900's in reality but I was proven wrong. Always nice to be wrong on occasion.
    Last edited by BentHeadTX; 10-08-2006 at 03:42 PM.
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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by BentHeadTX
    My BC900 terminated at 1.41 VDC on each cell, it has never had any problems charging at such a low level (I got lucky!) However, it would charge for around 20 minutes at 0.2C when I hooked it up to the Cadex. The ZTS tester indicated a full charge after coming off the BC900 so I proclaimed it good enough.

    Yeah, I have noticed that the results tend to be about 5 to 6% higher than the Cadex when I get the cutoff at 0.92V (won't do 0.90V) Not bad considering the Cadex costs over 80 times what a BC900 does, not bad at all. The BC900 agrees with the Cadex when it comes to cells capacity relative to each other. I plan on getting another LaCrosse so I can condition 8 cells at once for my LuxV and Quad XR-E Mag mods.

    The Powerex 1000's are the most impressive batteries I have tested, I can beat on them at 1.25C and they handle it without a wimper. I figured Sanyo came out with 1000mAH cells that might be 900's in reality but I was proven wrong. Always nice to be wrong on occasion.
    At 200ma rate, the BC900 should take approx. 13.5 hrs. on 2.7Ah cells. How long did the BC900 take? The forming charge should be strickly timed and not governed by a charger's termination. That's why I got the Pro Former becasue it's made just for that.
    Bill

    I'm a retired mechanic not a electronic/electrical engineer!

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by wptski
    At 200ma rate, the BC900 should take approx. 13.5 hrs. on 2.7Ah cells. How long did the BC900 take? The forming charge should be strickly timed and not governed by a charger's termination. That's why I got the Pro Former becasue it's made just for that.
    The batteries were 60% charged when I received them in the mail. The BC900 showed it "put in" between 850mAH and 970mAH across the dozen cells I tested. It terminated with each cell at 1.41 volts but the ZTS stated they were all full.

    Then put them on the Cadex and noted it continued to charge them at 540mA (C/5) for about 20 minutes as the voltage rose to 1.53 VDC per cell. I set -DeltaV at 8mV on the charger to "catch" the voltage depression quicker.

    The 1000mAH AAA batteries were formed at 80mA and it took about 10 hours to terminate the charge at 1.53V.

    A special note with the Cadex 7400ER when it charges/discharges. If it don't hit 100% capacity (or capacity limits you set) it does a reconditioning thing were it slowly tapers off the discharge rate under 1.00V until it hits about 40mA and dumps the cell to 0.40 V. It then trickle charges at about 15mA to 1.11V and then tapers up to charge until it hits about 1.16V and hits it at full. Normally, this will increase the capacity 2% between the first discharge and the second discharge on new cells. There is some other mumbo-jumbo it does but I don't recall at this point.

    Another weird thing about the Cadex is it won't terminate with temperature. The 8 cells in series hit 45C and the analyzer went into "rest mode" and I watched the temps peak at 48C and then cool down to 35C before charging resumed. The two cycles and reconditioning took 22 hours with a C/5 rate (540mA charge/discharge)

    Those AA batteries are resting comfortable in their plastic cases after a long week of testing. The AAA cells are getting baked by my constant playing around with the new Baltic super ultra power (SUP) in 1xAAA and 2xAAA configurations. The light makes it about 50 to 55 minutes before the regulator kicks down to "battery saver mode" and gets dimmer over time. According to Peak, the SUP version pulls almost 1.5 watts from a single AAA and over 2 watts from 2AAA... glad I have the new 1000's!

    If I want to, I can tell the Cadex to charge at 20mA for days until it terminates... don't think I have the patience for that at this point.
    Peak Pacific AAA UP brass (EDC) E01 (keys), Peaks, Arcs, Fenix, Q5 Aspheric HA-III Mag etc.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by BentHeadTX
    The batteries were 60% charged when I received them in the mail. The BC900 showed it "put in" between 850mAH and 970mAH across the dozen cells I tested. It terminated with each cell at 1.41 volts but the ZTS stated they were all full.

    Then put them on the Cadex and noted it continued to charge them at 540mA (C/5) for about 20 minutes as the voltage rose to 1.53 VDC per cell. I set -DeltaV at 8mV on the charger to "catch" the voltage depression quicker.
    When the BC-900 (or any other rapid charger) says the cells are full it then goes into a trickle charge. You can't rapid charge cells to 100%. I find that leaving cells on trickle in the BC-900 for about another 12 hours gives me about 5% more capacity. After 12 hours trickle I repeak the cells twice (just set the BC-900 to charge mode), letting them rest for at least 5 minutes after they're full. Usually the charger will only put about 100 mAh into the cells with each repeak. I then set it to test mode and let it do it's thing. This is the usual protocol I use when I test cells for capacity on the BC-900.

    I think the BC-900, at least in the 1000 mA charge/500 mA discharge setting, may be giving optimistic results. I'm in the process of testing to confirm this. I have 8 Assia 3000 mAh cells which tested at either 2830 or 2840 following the procedure outlined in the first paragraph. I tested them on my test jig at 600 mA (C/5). The preliminary results were 2515 mAh (to 0.9V/cell). I'm in the process of testing them at 500 mA but this time I gave them a forming charge so as to hopefully maximize capacity. By midnight I should have the results.
    Last edited by jtr1962; 10-08-2006 at 04:41 PM.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    BebtHeadTX:

    Your use of the word "terminates" confuses me! Like in this quote "The 1000mAH AAA batteries were formed at 80mA and it took about 10 hours to terminate the charge at 1.53V." A true forming charge as I understand it is a constant current charge with no -DelataV, ZeroDeltaV or DT/Dt form of charging termination used. It charges till you stop it or a timer stops the charging.

    Here's another one "If I want to, I can tell the Cadex to charge at 20mA for days until it terminates". This sounds like, you set a timer for so many days and it just stops, correct?
    Bill

    I'm a retired mechanic not a electronic/electrical engineer!

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    Str Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by wptski
    BebtHeadTX:

    Your use of the word "terminates" confuses me! Like in this quote "The 1000mAH AAA batteries were formed at 80mA and it took about 10 hours to terminate the charge at 1.53V." A true forming charge as I understand it is a constant current charge with no -DelataV, ZeroDeltaV or DT/Dt form of charging termination used. It charges till you stop it or a timer stops the charging.

    Here's another one "If I want to, I can tell the Cadex to charge at 20mA for days until it terminates". This sounds like, you set a timer for so many days and it just stops, correct?
    wptski,
    OK, I get it now... I thought forming charges were to charge the battery at or under C/10 until it terminated at full charge. Thanks for teaching me the correct terminology as what I was not doing was a forming charge. More of a low level charge with the Cadex reconditioning phase thrown in. All I know is after reconditioning, batteries perk up quite nicely wether the're new or older cells.

    Those Assia cells look very good for the price. I would get some but I have 12 2700's, 8 2500's, 4 2400's, 6 2300's, 4 2000's and 8 1700mAH AA NiMH cells in use. Forty-two AA cells to take care of and keeping conditioned is about my capacity at this point. Luckily I like 8AA Mag mods and 2AA EDC flashlights so they do get cycled quite often.

    A big thanks to SilverFox for testing all those batteries and charting them. It is quite the hassle to keep moving batteries around and keeping them all straight at different charge/discharge levels and such. All in the name of science (or being very anal)
    Peak Pacific AAA UP brass (EDC) E01 (keys), Peaks, Arcs, Fenix, Q5 Aspheric HA-III Mag etc.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by BentHeadTX
    wptski,
    OK, I get it now... I thought forming charges were to charge the battery at or under C/10 until it terminated at full charge. Thanks for teaching me the correct terminology as what I was not doing was a forming charge. More of a low level charge with the Cadex reconditioning phase thrown in. All I know is after reconditioning, batteries perk up quite nicely wether the're new or older cells.

    Those Assia cells look very good for the price. I would get some but I have 12 2700's, 8 2500's, 4 2400's, 6 2300's, 4 2000's and 8 1700mAH AA NiMH cells in use. Forty-two AA cells to take care of and keeping conditioned is about my capacity at this point. Luckily I like 8AA Mag mods and 2AA EDC flashlights so they do get cycled quite often.

    A big thanks to SilverFox for testing all those batteries and charting them. It is quite the hassle to keep moving batteries around and keeping them all straight at different charge/discharge levels and such. All in the name of science (or being very anal)
    Several of the BC900 meltdowns were at 200ma with the newer high capacity cells. What seems like a good idea for the first charge really isn't since the unformed cells may miss termination, although nobody really knows forsure. William Cheuh from MAHA had a somewhat different take on why a lower charging rate may cause a BC900 to overheat. It was more of a design flaw rather then a cell capacity vs charging rate vs new cell problem.
    Bill

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    At 500 mA the latest results are 2505 mAh (to 0.9V/cell), 2521 mAh (to 0.8V/cell), and 2529 mAh (to 0.7V/cell). This is about the same as my aforementioned 600 mA results. This means the results on my BC-900 at 500 mA are about 13% high.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Hello BentHeadTX,

    Your test results look good to me...

    Tom
    Behind every Great man there's always a woman rolling her eyes...

    Most batteries don't die - they are tortured to near death, then murdered...

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Hello Bill,

    I think William has a better story than thinking the cause of the melt downs was do to a missed termination.

    GP does tests where they charge a cell at 0.2C for an extended period of time. They claim that their cells can handle a 0.2C charge continually for a year. If you check a 2500 mAh cell, 200 mA is only 0.08C. That amounts only to a very aggressive trickle charge. At that charge rate, cells may warm up, but there is no way that they could get hot enough to melt down the charger.

    If something malfunctions in the charger and it is charging at 1 amp with no termination, then you can generate enough heat to melt things down.

    I find it interesting that we had a bunch of melt down reports, then nothing. Perhaps they changed something with the newer units.

    Tom
    Behind every Great man there's always a woman rolling her eyes...

    Most batteries don't die - they are tortured to near death, then murdered...

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Tom:

    Correct, Wiliam had a better theory about the meltdowns. Seems like it was a component design limit which could allow a current runaway condition.

    I think that he said that MAHA has had their cells on low current charges for weeks also.

    My BC900 melted at 700/350ma Test Mode on Duracell 2.3Ah cells that had about 5-6 cycles on them and not the first batch of four that I tested either! It was almost a year old to the day too.
    Bill

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    I have tried to promote the PowerEx brand ever since first hearing about them in the "Great Camera Battery Shootout" done a couple years ago. I knew they performed exceptionally better than 8-10 other batteries I had been using for various recorders, CD players, lights, mp3 players, toothbrush, etc. etc., but never had the equipment to prove it the way you did.

    Bravo!!!

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Say more about this?
    "The 1000mAH AAA batteries were formed at 80mA and it took about 10 hours to terminate the charge at 1.53V."

    Is this done one battery at a time? I visited the site, looked for a FAQ but didn't find one.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Forming is what's better done on the first charge at .1C or 1/10 of the rated capacity for approx. 16 hours using a constant current charge, meaning a dumb charger, no automatic cycling charger.

    You can do them one at a time and it's probably better. I myself normally do four at a time this way.
    Bill

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Added test results after testing four more Powerex AAA 1000mAH cells to the first post on the thread.
    Peak Pacific AAA UP brass (EDC) E01 (keys), Peaks, Arcs, Fenix, Q5 Aspheric HA-III Mag etc.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by wptski
    Forming is what's better done on the first charge at .1C or 1/10 of the rated capacity for approx. 16 hours using a constant current charge, meaning a dumb charger, no automatic cycling charger.
    Do I need special equipment to do this? I'm a newb, and have a Maha MH-402W on the way (with a bunch of the Sanyo 1000s and 27000s). Can I do this on the slow charge, or would I be looking at a different charger?

    Thanks

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    RobbW:

    I use this Pro Former but you need a 12V power supply to operate it. Some high end RC chargers have a lower ma ranges which have no monitoring for which you have to time. Some use low amerage over-night chargers for this but I'm not familiar with them!

    Maybe somebody else will reply listing their methods for a forming charge?
    Bill

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Hello RobbW.

    I use a dumb charger to make the forming charge to my cells.

    In my case it charges with 270 mAh so if you buy a similar charger you have to charge your 2700 mAh cells 14-16 h. Dont forget to make them empty first.

    Here:s how to calculate by Silverfox:
    Battery manufacturers state that it takes 14 hours to charge a battery when the current is set to 0.1C. If there was no loss, it would only take 10 hours. This gives us a nice ratio to work with. Take your 2400 mAh cells and multiply them by 1.4 and you end up with 3360 mAh. If you are charging at 500 mA, you simple divide the 3360 by 500 and end up with 6.72 hours as the charge time.

    We all know that the capacities of these cells are exaggerated, so I took the 2400 mAh and figured you would be good to get 90% of that. Now we have 2400 times 0.90 which is 2160. Multiply 2160 times 1.4 and we have 3024. Divide 3024 by your charging rate of 500 and we end up with 6 hours and a little change.

    Heat should not be an issue with this type of charge, as long as you shut the charger off at the end of 6 hours. If you wait for the charger to detect the peak, you may cook your cells while the charger continues to search for the end of charge signal. This is a problem with the first charge on a new cell, or on cells that have been in extended storage. Once the cells are "broken in," they tend to give a good end of charge signal that the charger can trigger off of and stop the charge.

    Anders


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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by Anders
    Hello RobbW.

    I use a dumb charger to make the forming charge to my cells.

    In my case it charges with 270 mAh so if you buy a similar charger you have to charge your 2700 mAh cells 14-16 h. Dont forget to make them empty first.
    Thanks for the information. I assume by "dumb charger" you mean a charger with low output and no charging "stages" to it?

    How do I "empty" the cells? Just run them in a flashlight until they are dead? Completely dead?

    Thanks for the formulas and thorough information. Much appreciated to this new user.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by wptski
    RobbW:

    I use this Pro Former but you need a 12V power supply to operate it. Some high end RC chargers have a lower ma ranges which have no monitoring for which you have to time. Some use low amerage over-night chargers for this but I'm not familiar with them!

    Maybe somebody else will reply listing their methods for a forming charge?
    Thanks for the link and info. I don't have a 12V power supply, but will look for an AC source or dumb charger. Whew! There's more to this than I imagined.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Wow. I just found this article on rechargeables.

    I need help.

    I have a MAHA MH-C401FS charger and eight AA Powerex 2300's. This was the highest rated batteries at the time.
    I didn't use them because they didnt seem to work as well as regular lithuims.

    What I didn't know is that I had to recycle them.
    What are your recomendations as to how I can do this.
    I also have a Calibeur DT830D meter. (Which sometimes is a mystery to me)

    You can see I'm new to this.
    Any suggestions would be appreciated.
    Last edited by balticvid; 10-22-2006 at 12:09 PM.
    Regards, Walt

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    By "recycle" do you mean deep discharge and recharge a few times, to be able to get them up to full capacity?

    If so -- either get a charger that will discharge and recharge (CCrane, newest Maha, many others) or run them down in a flashlight and recharge them at the low rate a few times.

    I rely on my Maha C401FS for slow full charge at home, and for travel and use the CCrane to test (one cell at a time) and charge up to 4 cells faster.

    But I am sure I'll eventually get the new Maha 9000 model.

    I don't think you meant 'recycle as in "not throw in the trash"?
    but if so -- any Radio Shack will take any kind of batteries, so will more and more hardware stores, and there will be more places. In California all batteries are now supposed to be collected to keep them out of the general landfill stream, as of Jan. 2006.

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    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Finally figured out the name of the priming program on the Cadex (buried in the thick book) it's called extended prime so I ran the 8 PowerEx 2700's in series for a 9.6V pack.

    It trickle charged them at 50 to 54mA for 16 hours then finished charging to 1.53V termination at C/10 (270mA) It discharged at C/5 (540mA) and ran two more charge/discharge cycles at C/10 charge and C/5 discharge.

    The 8AA 9.6V pack returned 93%, 98% and 99% so the forming charge works well even with batteries that have been used. Another good reason to get the Maha MH-C9000 since it has a forming charge (called break in) of C/10 charge and C/5 discharge.

    Running your batteries down and recharging them seems to purk them up quite nicely.
    Peak Pacific AAA UP brass (EDC) E01 (keys), Peaks, Arcs, Fenix, Q5 Aspheric HA-III Mag etc.

  26. #26

    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    I have these Powerex 2700 mAH AA cells.

    No scientific review from me, but they are nice. Behave well in magLite 2AA and 3AA, other lites and a digital camera.

  27. #27
    Flashaholic*
    Join Date
    Apr 2001
    Location
    Massachusetts
    Posts
    4,857

    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    From a digital camera forum, I found a link where this guy says the Powerex's are the best 2700mah battery he's tested as well. Not sure if he's ever posted on cpf.

    http://www.robertphotoblog.com/home/nimh-batteries/
    I live in a van down by the river

  28. #28

    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Thanks for the excellent review of the Powerex 2700mAh batteries!

    Please can someone confirm whether the MH-C204F charger (a few years old now) will FULLY & SAFELY CHARGE these latest Powerex 2700mAh AA batteries??

    I don't really want to have to upgrade my old charger to the newer one unless my old one doesn't do the full charge (time to charge is not a factor).

  29. #29

    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Quote Originally Posted by hotlips69
    Thanks for the excellent review of the Powerex 2700mAh batteries!

    Please can someone confirm whether the MH-C204F charger (a few years old now) will FULLY & SAFELY CHARGE these latest Powerex 2700mAh AA batteries??

    I don't really want to have to upgrade my old charger to the newer one unless my old one doesn't do the full charge (time to charge is not a factor).
    Anyone?

  30. #30
    Silver Moderator
    SilverFox's Avatar
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    Jan 2003
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    Bellingham WA
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    11,610

    Default Re: Powerex 2700mAH AA / 1000mAH AAA testing results

    Hello Hotlips,

    Welcome to CPF.

    If the 204 charges in series, it should work fine. If it charges in parallel, and the cells are not equally matched, it will not do a good job. If it charges in parallel, and the cells are evenly matched, and you leave the cells on the charger for an extended period of time after the charge has completed, it should work.

    Tom
    Behind every Great man there's always a woman rolling her eyes...

    Most batteries don't die - they are tortured to near death, then murdered...

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