Trex 600 with A123 cells

[ozace]

I have a desire to not use Lipo bags in my larger helicopters. I dont fly at a level where the ultimate power of a Flightpower or TP makes any difference to my enjoyment of flying.

For nearly a year i have been playing with different power sources.
When i first got my trex 600 it was bundled with a 6s2p 4400 Align lipo. It lasted 4 flights before deciding 600mm blades were too much for it.

I then moved to 10 Emoli cells and a 1515 Neu motor. This was a terrific combo at the time. It was heavy but power was good and was more than enough for me.

A123 cells started turning up in spetember 06 and i jumped in. The promise of safe cells, lighter weight (than emoli) and high discharge rates looked promising. The lower voltage however did cause some head scratching. It turns out 10s A123 cells pretty much match 8s lipo voltages, so back then i decided to try the 1400kv version of the Neu motor 1512 series. The thinking was the lighter motor (compared to the 1515) and the lighter cells (compared to emoli cells) would make up for the lower power available.

some A123 reading
( http://www.rcgroups.com/forums/showthread.php?t=566256 )

[ozace]

As i am constantly emailed and pm'ed across a few forums relating to these newer cells i thought i would start this thread.

Please note, so far none of these new cells can match a decent lipo bag for performance. If you are interested in peak performance these are not for you.

I dont push these cells for general use as we are still finding our way, but for those interested in playing these are a great place to start.

In short each cell is 70 grams, 3.3v nominal (drops to 2.8 under load) and 2300mah. They do not burn if mistreated but will fail. Charging can be done at 2c and 3c if you have a capable charger. Right now the E-station 902 is the only high end charger available that has A123 support built in.
There is a lipodapter available that allows the use of old nicad chargers.
available at slkelectronics.com (and lots of real useful info there as well.)

[ozace]

Where i am at now.

There heli carries a wattsup meter for all flights shich i use as a "fuel guage".

Pretty much all the Align upgrades (less metal blade grips), Align CF blades and Radix 92mm tails.

Weight ready to fly is 2685grams WITHOUT flight pack.

[ozace]

These A123 bricks i use are as they come out of the Dewalt drill packs.
cost is usually around the $100 US per pack delivered from ebay sellers.

I strip the outer case off and shrink whats left. I have a couple of bricks with the plastic braces left on and some without.

[ozace]

For my style of flying (sports with a few loops and rolls) i typically hit peaks of 1500 watts and fly for 5 mins. (takes 1700mah out of the cells)

I am not really into graphs of my flights as it offers little to anyone , but next time out i will strap on an eagle tree and tach the headspeed.

I have not added balance taps to these packs as i couldnt be bothered. I have recently checked the original pack from september and a couple of the 10 cells were out of wack. I charged them seperatly and have since flown with the pack. All voltages are now matched and holding. It seems these are much more tolerant of lazy practice or misstreatment than nay other cells in recent memory.

Life cycle is unknown in our apps right now but my number one pack has done about 100 cycles in E raptors, trex 600 and Jokers. Perfomance is identical to the new packs at this time.

[Ticidytoc]

Nice Adam, thanks for this thread.

[rcboosted]

I'm watching the development of these cells as people start to use them. Great information here. If your esc allows it, can you go 11S or 12S perhaps to make up for lower discharge rate? More V with less amp draw you can still get the same wattage.

[ozace]

Regarding the lower voltages, we have to watch weight as much as anything.
A 12s esc (CC HV) can run 14 a123 cells voltage wise , some are pushing to 15 a123s but its right at the limit of voltage for the esc's.

I am going to try for 11 and maybe 12 of these in a E620 and possibly 16 of them in a Joker if i get the balls.

:arggg: Personal rant time

ESC manufacturers need to drop the cell count garbage and go with voltages for ratings. THe cell count stuff is garbage, i have a couple of 10s rated esc's that wont arm with 10s current gen lipos as they hold their voltage too well.

CC have stated the HV series is 50v max( and they mean it) and the new powerjazz from kontronic is 63v max, thats the sort of info we need.

[rjg]

ozace,

As one of those emailing and PMing people, I wanted to say thanks for posting all of the info and pics... :mrgreen:

[ozace]

Some more ramblings

I chose this path (alternative power sources) after killing about $2000 worth of lipos in a 2 month block. It was starting to get expensive to power the toys.

As long as peak performance is not required these cells can be made to work well.

I aim for 1500watt average peaks from my 10s brick setups and they seem to do very well that way. (50amps from the 30v under load)

These cells can be difficult to work with, its best to leave the welded tabs attached and work with them, they cope with the amps and make pack assembly straight forward.

[Finless]

Still would like to see a GOOD flying video?

Bob

[spruce]

They are out there !! you just need to LOOK (for the 2nd time)

[pjpg]

I have been experimenting with these cells as well. I run a 10s setup in my Swift which produces more than enough power for me. I can get 6-7 mins of flight. I just sport fly with a few folls and flips. I find these cells ideal for learning new tricks and pushing my skills as they are durable , less prone to fire and of course the price. I have tried a 10s setup in my trex 600 and found the power to be decent but short flight times.I am using Z-power a50 800 motor. I have a 13s pack to try out soon. As Ozace has said they are not ideal for exteme performance.

[Finless]

They are out there !! you just need to LOOK (for the 2nd time)


Dude.... get it in your head... I am a LOYAL Helifreaker.... If they exist, I have asked you a couple of times to just post links and I would be glad to watch. IF they are "out there" and YOU KNOW where they are, why not just make it easy rather than make me look for them... POST A LINK!
I certainly would NOT do that to you! If I knew where the info was HF or not, I certainly would share it! Why are you being so obstinate?

I mean come on.... Is it THAT hard since you seem to know where all these vids are? Or maybe... there really is nothing to show?

Bob

[spruce]

Why are you being so lazy? Maybe thats why I'm "obstinate". I've seen the videos, I'm not the one asking for them.
I told you where they are.

Being a loyal Helifreak is great,Helifreak is great, just remeber what they say about eggs and baskets.

[Finless]

Why are you being so lazy? Maybe thats why I'm "obstinate". I've seen the videos, I'm not the one asking for them.
I told you where they are.

Being a loyal Helifreak is great,Helifreak is great, just remeber what they say about eggs and baskets.

Well never mind then.... It is obviouse you dont want to HELP HERE so other helifreaks dont have to go looking either.... Not sure I understand your reasoning here? Seems you have something to hide or just being a jerk....

Fine.... I will wait as I am in no rush nor do I actually care. You all want to show how great these cells are, I keep asking, still not seeing it.... So no sweat off my brow!

Bob

[spruce]

ohh why not, heres one (bad one :lol: ) of many.

http://youtube.com/watch?v=DAwoh0r5hI0

[spruce]

Well never mind then.... It is obviouse you dont want to HELP HERE so other helifreaks dont have to go looking either.... Not sure I understand your reasoning here? Seems you have something to hide or just being a jerk....

Yes you guessed it, I HAVE SOMETHING TO HIDE :roll: .
No I'm tired of people ( in general) wanting shit handed to them, IF YOU WANT SOMETHING GO GET IT, DONT WAIT FOR SOMEONE TO HAND IT TO YOU.

I'm more than happy to help someone with an "open mind". Your minds been made up on A123s a few topics ago.

Something like " if A123s are all that why arent FP or TP jumping on them".

Maybe ask your friend Andy about me being helpfull.
Have a wonderfull day.

[Finless]

No I'm tired of people ( in general) wanting shit handed to them, IF YOU WANT SOMETHING GO GET IT, DONT WAIT FOR SOMEONE TO HAND IT TO YOU.


Hmmm seems you are a very MAD person? THIS is not the HF way and if you want to talk like that and be an ASS then go to RR or RCG or where ever you came from! My mind was not made up... I have doubts but instead of helping and SHOWING OTHERS, you would rather be an a jerk and not HELP....

You sound JUST like so many posts I have seen at those OTHER places when someone asks a question that has been asked before. "Do a SEARCH and FIND it". Not a very helpful person and NOT a CONTRIBUTOR!

Now your YELLING.... OK... move on dude.... show or blow!

Bob

[robl]

dude, thats a logo 10, thats not even the same size as a TREX600, post a video with someone flying a Trex600. And I did search and I didn't find anything. Even searched Youtube.

[Finless]

ohh why not, heres one (bad one :lol: ) of many.

http://youtube.com/watch?v=DAwoh0r5hI0


Hmmm.... considering the HUGE wind that actually didnt look to bad... Head speed sounded good.... I would like to see a vid in good coditions and full flight time BUT... this didnt look that bad!

What was the configuration there?

Bob

[rdespins]

Hi Bob,

I think this is the video he was refering too. It is quite impressive, but to me the system is heavy 8-9lbs, however since the machine has 620mm blades, I beleive it ends up with lower disc loading than a 7 lb T-600.

http://www.tppacks.com/video/eTitan%20Z50A-600%2015s-a123-M1%2011-19-06.wmv

Heres a snippet of the comments Gary Goodrum had on the system:

It's a bit hard to hear in the video but the motor got to about 133-134F, the SAE controller to 104F and the packs to 100-110F. Ambient temps were about 90F.

I had IDLE 1 set to about 80%, which was around 2100-2150. IDLE 2 was 100%, which ended up around 2700 in the beginning. I think what will work will best is setting IDLE 1 to about 2250-2300. That should still have great power and will up the durations significantly. With it at "full tilt", the durations are only about 4-4.5 minutes. With a bit less h/s I think you could get about 5.5-6 minutes of hard flying.

Power with a 12s-3700 FP or 12s-3850 TP Extreme setup should be similar,if not a bit stronger. With a 2700 h/s I'd put this best up against ANY drag racer. I think Ken will definitely have some competition at next year's IRCHA. This motor can definitely handle the load. The Hacker A50s have very low resistance numbers (16 mOhm...), so they are extremely torque'y (the torque constant of a motor is generally inversely proportional to its resistance...) but they run so hot the effective resistance rises with the heat. The Actros have relatively high resistance values (40 mOhms...) but they move so much air through that the "effective" resistance is fairly low. The Z-Power Z50A-600s are right in the middle, resistance-wise (27.5 mOhms...) and they also move quite a bit of air, not quite as much as the Actros, but definitely a ton more than the Hackers. One of the major differences between the "A" and the previous versions of the Z50s is they redesigned the cores for more efficient wiring and for better airflow. In any case, the combination of fairly low resistance, a very efficient wind to begin with and great airflow, seems to be working extremely well. I'd put this motor up against anything, at any price.

The other thing that makes me quite happy is the performance of the a123 cells. Unlike the eMolis, which worked okay but couldn't be pushed too hard, using these doesn't require us to take a performance hit. This 15s setup is much stronger than any 10s LiPo setup I've run in a Raptor and is only bested by a 12s setup of the latest LiPos, and even there I'm not sure the performance is all that different. The 12s-3300 FP setup was a bit stronger in the e620SE, because the packs were lighter, but we ended up puffing them. A 12s-3700 setup weighs about the same as the 15s a123 configuration, so the difference,if any, will be less I think.

-- Gary

Ron

[Mercuriell]

I think spruce is a flamer from RR LaLa land - I spent 30 mins searching and could only come up with the http://www.youtube.com/watch?v=RStBQYPE5sM in addition to the posted link - as you say Bob - not the HF way

[ozace]

Well that got interesting for a short while :badair: .

I have yet to see anyone post a vid of a 600 with a123 cells. I do hope to get some tomorrow of mine.
If i do i will be requiring help to get it suitable for viewing (bob, matt etc)

[spruce]

I'll give you something to blow on . The only Ass here is the one telling people to move on because he's to stupid to use a search function, or to simple minded to think maybe there is info in "other" places. Everytime someone comes up with something "new" your the first one to doubt it ( lets think back to the 1st postings on a 10s trex) "show me" "I dont believe it until I see it". You want /expect everyone to take what you tell them for fact but when the shoe is on the other foot its, "show me or your full of it"

Robl. I said that is one of many, funny others can find the videos. I guess your "search" is broken.

Mercuriell joined sept 2006, yeah you caught me. your such the detective.

Anyhow FTR I always said A123s are Not lipo replacements, but they do work.
You guys will just have to wait for Bob to tell you that they work after he "sees some more videos.

Helpfull? Hmmm I seem to remeber donating to the freak, when it was ready to close shop, were you even here for that ?

I'm done with you boys on A123s, believe what you want, I've "seen" them and they work.