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Old Jan 17, 2009, 10:00 AM
ProgressiveRC
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Seattle, WA
Joined Dec 2006
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Yes, I have done some testing of FalconEV/Advanced Lithium cells, some good, some not so. What would you really like to see (size/test/comparison)?

As for LifFePO4 and LEDs, well, that must have been on candlepowerforums if anywhere:

http://www.candlepowerforums.com/vb/

Which LiCo cells are you referring to? Any chance of a link? My experience is that many emerging cells, including Advanced Lithium, have specific, atypical cut-off voltages during charge, i.e. 3.65V or 3.80V at full charge. The iChargers work great for this as cut-off charge voltage is fully adjustable for any chemistry or charge program.

- David
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Old Jan 17, 2009, 08:13 PM
QPower 18650
madhun1's Avatar
Sunshine Coast
Joined Jun 2006
1,495 Posts
Quote:
Originally Posted by write2dgray
Yes, I have done some testing of FalconEV/Advanced Lithium cells, some good, some not so. What would you really like to see (size/test/comparison)?

As for LifFePO4 and LEDs, well, that must have been on candlepowerforums if anywhere:

http://www.candlepowerforums.com/vb/

Which LiCo cells are you referring to? Any chance of a link? My experience is that many emerging cells, including Advanced Lithium, have specific, atypical cut-off voltages during charge, i.e. 3.65V or 3.80V at full charge. The iChargers work great for this as cut-off charge voltage is fully adjustable for any chemistry or charge program.

- David
http://store.peakbattery.com/lithium...-lco18650.html

These are the LiCo unit's I were referring to. Nominal voltage is 3.7v but no other info available.

I have a hyperion duo.

Candlepower forums doesn't look familiar but interesting reading; thanks.
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Old Jan 17, 2009, 09:12 PM
ProgressiveRC
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Seattle, WA
Joined Dec 2006
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You know all I know about those from DLG, you might try sending an email peakbattery for some more info - I'd be curious to know. They are listed on my LiFe page, although the comments note that they are lithium cobalt oxide. I have never personally seen or tested any and they have no given C rating.
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Old Jan 17, 2009, 10:46 PM
QPower 18650
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Sunshine Coast
Joined Jun 2006
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Quote:
Originally Posted by write2dgray
You know all I know about those from DLG, you might try sending an email peakbattery for some more info - I'd be curious to know. They are listed on my LiFe page, although the comments note that they are lithium cobalt oxide. I have never personally seen or tested any and they have no given C rating.
I have just emailed peakbattery and will post up any information they will supply.

At that size and 2000mah they would be very useful if the C rating is decent (and accurate).

If they look half decent would you mind if I had them ship you a hand ful for testing? Although I have an eagletree and wattsup meter I've not got any other battery testing equipment.

I'll have to set up a test rig one of these days.
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Old Jan 17, 2009, 10:57 PM
ProgressiveRC
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Not at all - that would be great. I'd be happy to run the standard tests on a pair of samples up to a given C rate and any other tests you desire. I just got through hooking up my dual CC-400 dischargers - up to around a kW limit now when combined with the CBA II, this set-up is good for over 250A on single cell LiFePo4s and 75A continuous discharge on a 3S LiPo.
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Old Jan 17, 2009, 11:57 PM
QPower 18650
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Sunshine Coast
Joined Jun 2006
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Quote:
Originally Posted by write2dgray
Not at all - that would be great. I'd be happy to run the standard tests on a pair of samples up to a given C rate and any other tests you desire. I just got through hooking up my dual CC-400 dischargers - up to around a kW limit now when combined with the CBA II, this set-up is good for over 250A on single cell LiFePo4s and 75A continuous discharge on a 3S LiPo.
Thanks. I'll keep you posted and PM when I knoe more.
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Old Jan 19, 2009, 04:24 AM
QPower 18650
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Sunshine Coast
Joined Jun 2006
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Quote:
Originally Posted by write2dgray
Not at all - that would be great. I'd be happy to run the standard tests on a pair of samples up to a given C rate and any other tests you desire. I just got through hooking up my dual CC-400 dischargers - up to around a kW limit now when combined with the CBA II, this set-up is good for over 250A on single cell LiFePo4s and 75A continuous discharge on a 3S LiPo.
Attached are some specs as supplied by the vendor.

At $12/cell though I'd have to question using these over A123
These are for the Gold Top LifePo4 from Advanced Lithium
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Old Jan 19, 2009, 09:18 AM
ProgressiveRC
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Seattle, WA
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Now that looks familiar - notice the D.Gray in the lower left of the graph. Well, I guess I have tested those cells. Not up to A123 under loads over 15C, but capacity is very near spec.
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Old Jan 20, 2009, 04:40 AM
QPower 18650
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Sunshine Coast
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As for the LiCo; so far the only info I can find about them is in relation to the risk of fire if overcharged, and reduced life expectancy in high current drain applications.

A123 discharge/charge capabilities in various form factors with the weight and cost of the LiCo is what we need; is that too much to ask?
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Old Jan 22, 2009, 08:05 AM
QPower 18650
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Sunshine Coast
Joined Jun 2006
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Quote:
Originally Posted by write2dgray
Not at all - that would be great. I'd be happy to run the standard tests on a pair of samples up to a given C rate and any other tests you desire. I just got through hooking up my dual CC-400 dischargers - up to around a kW limit now when combined with the CBA II, this set-up is good for over 250A on single cell LiFePo4s and 75A continuous discharge on a 3S LiPo.
Managed to find the spec sheet for the LiCo's and the manufacturer of the gold top LifePo4 32650 cells.

Going through the motions of obtaining samples of both to test.
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Old Jan 22, 2009, 11:28 AM
AKA Don
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Humm? Max discharge 3.0 on a 2.0 Ah battery. 1.5C sounds like its limited to low power service.
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Old Jan 22, 2009, 05:39 PM
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great info. Thank you very much.. Keep up such a wonderful work!
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Old Jan 23, 2009, 04:10 AM
QPower 18650
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Sunshine Coast
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Quote:
Originally Posted by bz1mcr
Humm? Max discharge 3.0 on a 2.0 Ah battery. 1.5C sounds like its limited to low power service.


Looks that way; probably no significant benefit for RC applications in all but the lightest of duty. Significant weight reduction over a Lifepo4 cell of the same capacity.
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Old Feb 09, 2009, 12:14 PM
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USA, MO, St Charles
Joined Nov 2005
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What is a "Bleed Rate"?

Seems to be noted on only some of the Bantam clone chargers on the http://progressiverc.com/Research.html list.
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Old Feb 09, 2009, 12:26 PM
ProgressiveRC
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Seattle, WA
Joined Dec 2006
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Bleed rate is the effective discharge rate (per cell) available to aid in cell balancing. Bigger is better . It is listed for many chargers and is also given for all balancers on the "balancer" list where available.

- David
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