J Lachowski

My Feedback: (46)

How is everyone doing with these packs? How many cycles? I have only one set with 23 flights to date. Looking for feedback to determine whether to go with these packs next season.

I have been running the Duralite/FP 5350's primarily and am at 85 cycles on two sets and 62 on another set. My 4th set of 5350's had a cell puff at 57 flights. The puffing goes down after it cools down. On another subject, is it safe to continue its use?

OhD

My oldest pack has 84 flights on it and is still working well although it was probably abused for six flights starting at flight 56 when I installed a DualSky 11T with a higher Kv and then flew it in some 106F weather. After that it tended to swell and get hot after a flight but it goes back to normal after cooling down. A bunch of us are now looking at the internal resistance of each cell to try to determine when to discard or retire our packs. Right now the cells run from 6.8 to 7.5 milliOhms in this pack.

I have a newer 15C pack that has 30 flights and its numbers run from 2.8 to 3.3 milliOhms. For comparison purposes my old TP Prolites run from 6.9 to 8.5 after 200 flights and 6.3 to 7.3 after 140. These packs were also abused during their lifetime.

I'm thinking that numbers over 7 milliohms might be too high for use in competition. Scott Covey and I were trying to get a handle on this and made the assumption that the peak current is 65 volts. If we have an average of 7 instead of 3 we are losing (10x.004)x65=2.6 volts

2.6x65= 169 Watts

169 Watts=.226 HP

It is not as simple as this as everything is varying during a flight but it gives us a feel for what we are losing.

The jury is still out on the TrueRC packs but we reason that if we can get 100 flights out of them they are a good value and it looks like we will. However, I'd wait until I was going to need them as I suspect they degrade sitting on the bench. Anyone have data on that that they'd like to share?

Jim O

Pablo Kuri

My oldest pack has 200 flights and still going strong. Its the Tp 5300 prolite. P09 and F09.

Regards

Pablo Kuri

serious power

Hi Jim,
How are you measuring resistance on a per cell basis.

Brian

J Lachowski

My Feedback: (46)

The FMA Cellpro 10S Charger does this for you everytime you charge.

J Lachowski

My Feedback: (46)

I know what other packs do, I am more interested in the True RC packs which are significantly cheaper in price than the Thunderpower, Flightpower and other packs out there.

woodie

I have 2 TrueRC 5000 10C sets and my experience has beens similar to Jim's. They have good power and charge fairly evenly. A little more balancing than my FP and TP packs but acceptable. Both got a little puffy after a few flights but have not gotten any more so over the past 2 months. Only time will tell, but they seem like a reasonable value for the money. At the current price, if you get 100 fligths out of each set then they are about the same cost per flight as the more popular brands.

Woodie

OhD

Brian - I'm using the FMA CellPro 10S as Joe mentioned.

Joe - If you have a CellPro can you give us the cell R on the FlightPower packs?

Woodie - I have only heard of the TP Prolites getting 200 flights and they cost almost three times the TrueRC so the TrueRC looks like the winner. What other packs would you consider based on longevity per dollar?
Maybe we should buy one or two packs for performance even if the cost is higher?

elan120

My Feedback: (1)

Jim,

I have 5 FP packs IR reading already posted on Chris Moon's website using CellPro.

Kevin

OhD

Thanks Kevin, I see Joe has posted his too. At first glance his numbers look pretty high. Doubt that he'll get 200 flights.

Jim O

woodie

Jim, that's true, only the TP Prolites seem to last that well. Probably an indication of the 'C' effect that keeps coming up.

My TP5300s are approaching 300 flights and can still get me thru a P09 FAI sequence adequately. I typically use them for warm up practice flights. However, I will also say, I stopped using them for competition at about 200 flights so I guess they were 'retired'. There is also an advantage to using the batteries life more quickly and that is you replace the batteries more often. Even if the cost is only slightly better, you are flying with fresher batteries on average.

I ordered a Cellpro just so I could track the IR of my packs. I am very curious how they act over time.

Woodie

serious power

Hi Jim,
I'll check it out,thank you.

Brian

J Lachowski

My Feedback: (46)

Yep, at this point I'm hoping to get a 100 flights. Due to lack of experience early on I did abuse one or two sets once or twice. If I knew then what I know now I might have a little more longevity out of them. I'm hoping at least 100 flights on 3 of my sets. These packs will be relegated to my Angel S for use once I get there.

If you look at the numbers in my one set there, the one that has one cell at 8.5 is the one 5S pack that swelled up when it got hot and then returned back to normal shape when it cooled down. I didn't keep a good track of these packs like I should have but I'm willing to bet that one set was the one I discharged a little too low one time (grabbed a used set by accident). I now keep my flights to 8 minutes max period. A big plus for next years Masters pattern is that it appears to takes a bit less time to fly which should be good for reduced abuse if you adhere to a strict regiment of sequence and land which is what I do all the time now. All 4 sets have gotten hotter with age. They are all typicallly 130ish on warm days, 80 plus degrees. Power is still good enough on the 3 sets. I haven't used the 4th set since the cell swelled up, hence my question should I continue use or ditch at least the 5S pack with the swelling cell.

OhD

[/quote]

Yep, at this point I'm hoping to get a 100 flights. Due to lack of experience early on I did abuse one or two sets once or twice. If I knew then what I know now I might have a little more longevity out of them. I'm hoping at least 100 flights on 3 of my sets. These packs will be relegated to my Angel S for use once I get there.

If you look at the numbers in my one set there, the one that has one cell at 8.5 is the one 5S pack that swelled up when it got hot and then returned back to normal shape when it cooled down. I didn't keep a good track of these packs like I should have but I'm willing to bet that one set was the one I discharged a little too low one time (grabbed a used set by accident). I now keep my flights to 8 minutes max period. A big plus for next years Masters pattern is that it appears to takes a bit less time to fly which should be good for reduced abuse if you adhere to a strict regiment of sequence and land which is what I do all the time now. All 4 sets have gotten hotter with age. They are all typicallly 130ish on warm days, 80 plus degrees. Power is still good enough on the 3 sets. I haven't used the 4th set since the cell swelled up, hence my question should I continue use or ditch at least the 5S pack with the swelling cell.
[/quote]

I plotted most of the data for the FP 5300s and they look like they fall on a fairly straight line. If I compare my TP Prolites with many more cycles they look like Ps at 80 cycles. Maybe there is something about the 4P vs. 1P we need to know.

Joe, your data showed the one cell at 9.4 mOhms and you might get a few more flights but it is definitely not a good cell and I'd retire it. I've heard of more than one guy almost burning his plane to the ground trying to get one more flight.

Jim O

J Lachowski

My Feedback: (46)

The 9.4 is on the 5S pack that is still OK believe it or not. The pack with the puffed cell had all lower resistances on each cell except the one at 8.5 which must be the cell that puffed. Hmm, this should be an adventure, these are the first Lipos that I have ever had to dispose of in the 3 yrs I have been tinkering with electric. Oh, well soner or later<g>

OhD

Can't remember how to convert an Excel chart to a JPEG. Help.

can773

My Feedback: (1)

Select the chart and then just do a copy and paste it into paint or another image edit program. Save as .jpg.

Should work

patternflyer1

My Feedback: (11)

Joe,

Don't fly with a bad cell. I had a few packs going bad and it nearly cost me the Abbra a few weeks ago. Made for good marshmallows though after I pitched it straight outta the plane and into the parking lot at the field (almost caught fire in the plane). I will never fly with a pack that isn't cutting it again.


Chris

mups53

My Feedback: (41)

Has anyone successfully replaced a bad cell in a pack? Say you had 3 True packs and all had say around 50 flights. Could you sacrifice 1 pack and use the good cells off of it to keep 2 packs healthy for a long time?
I started off the season with 4 brand new packs flying an Integral with an AXI F3A CCHV85 and a APC 20.5x14 prop. Pack # 2 a TP 5000 10s V2 went completly bad on flight 28. Pack #1 another TP V2 went bad on flight 45. Both were sent back. Packs 3# and #4 are both True 5000's but the longer packs that Dan was selling earlier in the year have been going really strong with around 50 flights each. I had Dave Snow run the packs on his Cellpro about 3 weeks ago and he told me the TP pack #1 had a bad #8 cell and sure enough it puked a few flights later. The True packs seemed to be showing relativly healthy IR data in the 5's if I remember right. In the air they feel as strong as when they were new. I tend to fly a wide open style and they were delivering for me all year.
I've learned to be very careful with flight times and like Joe I limit my flights to a masters sequence and land. About 7.5 minutes on average. My average amount on mils put back in all packs this season was 3300 per flight.
From what I've seen I think the True long packs are better than the True short packs that he was selling for a while. I think Dan has gone back to the long packs. I'm refering to the 10C packs only.
I will be buying a Cellpro charger so I can get a better handle on the details. Until then I rely on the info on the net and having a great resource like Dave Snow to fly with. Thanks, Mike Mueller

patternflyer1

My Feedback: (11)

From what I understand Mike, It's not good to try to replace a cell. As the new cell will have a different resistance and will probably make the other cells have to work harder. I'm sure you've read Jim Oddino's info on the Zippy's. I feel the same about running 2 5 cell packs that aren't all matched cells also. The Flight Powers at least give you the option of that if you purchase the matched sets. I'd like to see others like True Rc follow suit as I think that's the way to go. Still, I may have to get some True Rc's as they are affordable.

Chris

mups53

My Feedback: (41)

Thanks Chris. I don't have any affiliation with True beyond the fact that Dan lives real close to my house and I've gotten to know him pretty well. Being a competitor I lean towards products that allow me to compete at the highest level. I would have expected the V2 TP packs I got at the beginning of the season to be my best competition packs. In fact they were not to my surprize and disappointment. I think if I go with TP anymore it will be with the prolite series.
Chad has a nice report on them on Electric F3A.com

http://www.electric-f3a.com/TP%205200%20ProLite.htm
I'll bet with proper care and best practices and charging with the Cellpro we could get 200 flights. Plus Thunder Power has the best customer service I've ever seen in this industry.
As far as stealing cells from a pack to save another I think if the usage and the amount of IR matched the average of the rest it should work. Not that I would ever do it just throwing out the idea. Mike Mueller

patternflyer1

My Feedback: (11)

Hey Mike, I agree with the fact that if the cells are close to the same age, it should be fine to swap. I thought you were talking about swapping one out with a new cell.

As for the Pro lites, they seem to be hard to beat for longevity IMO.. My original Flight Power 3700's were really good also. But the F3A's are a different chemistry so I've been told. If I could afford pro lites, I would buy them..

C

OhD

I figured out how to do it.

In the chart I plotted the values of the highest and lowest cell resistance against the number of cycles on the pack. You can almost predict where these packs will be at a given number of flights. If you have a bad cell it sticks out like a sore thumb.

OhD

It looks like the 8.5 and 9.4 are in the same pack, the one you said puffed. Not good.

J Lachowski

My Feedback: (46)

They are in the same matched set of packs but not the same individual 5S pack. I would also like to note that all my sets of 5S packs where also used as single 5S packs in a Sebart Angel S. I did make sure these packs maintained equal number of cycles while doing that though. So again, my mode of use is not exactly ideal. The max static draw on the Angel S was measured around 60 amps. I flew no more than 8 minute flights on it, as well. Battery temps were typical of what was done in the 10S mode in my 2M planes.

One other thing. My usual mode of charging is to charge each 5S pack individually, not hooked up together as a 10S pack when charging. Does it really matter which configuration you charge them in? All are charged at 1C.