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Old Jul 24, 2005, 10:24 AM
Southern Pride
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Haralson County GA. USA
Joined Oct 2004
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CBA LiPOly Capacity Decay - fAct or Fiction?

CBA LiPOly Capacity Decay - fAct or Fiction?

Mine do ,do yours?

Lose capacity with each cycle that is.

Edit: Sometimes we see what we expect to see instead of what is really there. IA-Flyer post #5 was the only one to catch my error on this graph.
The TP ProLites on graph are two different packs and the one with the lower capacity is the one with the least number of cycles. The use of two dirrenent ProLits was an error on my part. I saw dsch 6 and 20 and the difference in capacity seemed to fit. I will update this graph with the same ProLite used next time so that it has real meaning.


Charles
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Old Jul 24, 2005, 11:03 AM
Space Coast USA
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Space Coast
Joined Oct 2000
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I'm sure you are correct. My guess is that it is an exponential decay....Slow at first and quicker near the end of it's cycle life. Should be interesting if you keep that chart updated.
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Old Jul 24, 2005, 11:17 AM
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Charles,

Some LiPo's capacity-decay faster than others, in my experience. I run a "condition check" graph on the cells I think are more promising, after they go through 1 - xC + burst discharges.

While the decay differences between the cells is quite large, it's not much to go on, because so few cycles are observed.

I guess all we can infer from my experience is that some cells may not get outright ruined with early overstress.

- RD
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Old Jul 24, 2005, 11:28 AM
Southern Pride
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Haralson County GA. USA
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Quote:
Originally Posted by RD Blakeslee
Charles,

Some LiPo's capacity-decay faster than others, in my experience. I run a "condition check" graph on the cells I think are more promising, after they go through 1 - xC + burst discharges.

While the decay differences between the cells is quite large, it's not much to go on, because so few cycles are observed.

I guess all we can infer from my experience is that some cells may not get outright ruined with early overstress.

- RD
Welcome back amd hope the fishing went well.
I agree and that is one point which concerns me when it comes to purchase decesions being made on very short term testing / useage. Most any LiPoly made today will perform well for perhaps 15-25 cycles but many will suffer rapid becline in ability to maintain volts under load and ability to deliver a high percentage of their capacity under load.
I first became aware of this difference when using / testing E Tec 700 HPs and Thunder Power 730 Gen.II and later TP 730 ProLites.


Charles
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Old Jul 24, 2005, 01:44 PM
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Welcome back RD!

Hi Charles,
Is that the same TP 1320, I see in the graph it is labeled #3 & #1?.
If it’s the same pack it appears to have increased strength and capacity after 20 discharges.
That Tronics 1300 looks very good too, but my mini funtana is wishing it was closer to 3oz… What’s the price on the Tronics 1300 3s? It might be worth considering.

Looking at your other lifespan graphs, it appears that they drop capacity at a predictable rate until about 70 discharges, then do a better job of holding capacity until they approach the end of their life. It’ll be interesting to see how these hold up.
Interesting graph, thanks!
Jim
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Old Jul 24, 2005, 02:07 PM
Southern Pride
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Haralson County GA. USA
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Quote:
Originally Posted by IA-Flyer
Welcome back RD!

Hi Charles,
Is that the same TP 1320, I see in the graph it is labeled #3 & #1?.
If itís the same pack it appears to have increased strength and capacity after 20 discharges.
That Tronics 1300 looks very good too, but my mini funtana is wishing it was closer to 3ozÖ Whatís the price on the Tronics 1300 3s? It might be worth considering.
Looking at your other lifespan graphs, it appears that they drop capacity at a predictable rate until about 70 discharges, then do a better job of holding capacity until they approach the end of their life. Itíll be interesting to see how these hold up.
Interesting graph, thanks!
Jim
I use the same cell / pack name for all test and that #3 is half of one of my
Speed Wing 400 packs also graphed here.

<Edit
# 1 is a different pack ,my first 1320 ProLite and yes it did test a little lower and I did not catch that they were different packs when doing the overlay. Thanks for noticing. >
I believe somewhere around 40-$45 mine was furnished by Jacky of Tronics for testing. Maxamp is now carrying these cells from what I have read here.


Charles
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