Emoli packs on the Lepton

[FrittsLogic]

I just finished my first FFF testing with my Lepton. I wanted to see if emoli cells could be used sucessfully. I'm just a sport flyer, so maybe these things won't work for hardcore 3d'ers, but for me today's results were fantastic. I use a 4s setup with Hyperion Z3025 10 turn, Jazz 55-10-32. My test flights were at 2300 rpm and logged with the eagle Tree E-Logger. On my website, menehunerotorworks.com, I have the results and a version of the KC spreadsheet with my configurations and updated for the power levels I actually saw with this heli. I'll be testing 2500-2600 rpm this weekend.

Summary:

Head speed used - 2300 RPM

Flight time- 7 min 20 sec

mAh used - 1972 mAh (out of 3000 available)

Average power= 245 watts

Average current = 20 A

Peak current during full power climb = 43 A (within the 15C emoli limit)

Min voltage during flight 14.0 VDC

[GGoodrum]

Just out of curiosity, how is the pack mounted? Do you have any pics?

-- Gary

[FrittsLogic]

Gary, I have photos on my website. I velcro it down on the battery tray, and hold that down with a velcro strap just like the lipo packs. Using the battery tray end stop at the default position, my CG was essentially perfect. I had to widen the battery tray supports by adding 3 washers at each post so the 53mm emoli stick packs would fit the 50 mm opening. These packs way only a few grams more than a Hyperion 3700 4S pack.

[Gscott]

I successfully flew mine with a 4s pack yesterday. Looks like a 5s pack will fit if you can find some type of spacer for the front mounting scews.

[Finless]

FrittsLogic,
Cool! nice pictures of the Emoli pack install!!!
I am going to have to get a set of those now.......

Bob

[GGoodrum]

Yes, great pics, thanks. :)

Would a 5s "flatpack", in a side-by-side" configuration fit, like it does here in my QJ/EP-8 "SE" prototype shown below?

http://www.tppacks.com/photos/ep-8SE-09.jpg

http://www.tppacks.com/photos/ep-8SE-08.jpg


If so, I think this would give better performance and longer durations, over the 4s setup. You could use an A30-12XL and the 20T pinion. If more pinions become available, you could use an 8XL, like I'm doing with the ep-8, and get even better performance.

-- Gary

[Finless]

GGoodrum,
I just measured and the spacing between the front frame runners is 50mm.
I dont know how long Emolis are but if they are more than 50mm then you wont be able to slide them through the from of the heli. BUT you might be able to go in from the side. Can you measure how long the pack is?
Or you can space out the front frame runners as FrittsLogic did.

Bob

[GGoodrum]

The cells are 26mm in diameter and 70mm long, so a 5s side-by-side pack is about 70mm x 130mm x 30mm.

[Gscott]

I run a 4s flat pack like that and it CG's fine. I run my pack right up against the support bars. There is room in the battery tray for a 5s flat pack but I don't know if the CG would be correct. With some spacers you should be able to slide the pack farther forward if necessary.

[Finless]

The cells are 26mm in diameter and 70mm long, so a 5s side-by-side pack is about 70mm x 130mm x 30mm.

OK the 70mm width wont allow you to insert the pack through the front between the frame runners BUT the 130mm length will allow you to insert the packs from the side. You wont be able to slide them forward so if it CG's going in from the side you will be fine. If you need to slide them forward to get CG you will have to space out the frame runners as FrittsLogic did.

Bob

[FrittsLogic]

If they can slide in from the side, the CG should move fwd (5 vice 4 cells with same geometric center of gravity), so you will probably have to nudge them back. removing the battery tray back stop would allow a little more room to do this. I've got more emolis being shipped to me (they're working out so well, I want enough to fly all day without recharging), I'll check 5 loose cells to see how it all fits and check CG, before I make them into more 4s packs!

-Don

[FrittsLogic]

More testing today on the emolis.
Head speed used - 2550 RPM
Flight time- 7 min 40 sec (from start of spool up)
2547 mAh used (out of 3000 mAh available)
Average power= 269 watts
Average current = 20 A
Peak current during full power climb = 49 A
Min voltage during flight 10.3 VDC (at last seconds of flight on ground before spool down)
Voltage started to drop off sharply at 12.85V, 2425mAh, 6 min 50 sec, there was plenty of control to allow landing.
Post flight temperatures:
Battery 129F
motor 139F
ESC 120F

Data and graph on my website (menehunerotorworks.com)

This flight consited of standard circuits as fast as I could make them. One full power climb also conducted for max current (easily seen on graph of data). I continue to be impressed by these emoli cells and how they work so well with the Lepton!!!

[Finless]

OK FrittsLogic, now you got my attention!

How can I get 4 of these cells to try out?

I have heard but not followed the Emoli thing so is there a site that gives a "mind dump" of how to get them, charge them, etc?

Bob

[vksy]

Light reading: http://www.swift-tuning.com/emoli.pdf
Heavy reading: http://www.rcgroups.com/forums/showthread.php?t=456011

[Finless]

vksy, thanks for the info... Did a little research.
Looks like Lowes or Home Depot will soon have packs I can buy.

BUT, I would really like a favor from someone. I personally would like to test these myself without going to all the trouble right now of buying and making my own packs. You all know I am capable but I just dont have the time right now.

I am willing to buy a 4S pack straight out from someone at a totaly fair price. I would like it to be new and ready to solder on a deans connector. I will paypal the seller directly.

Any takers?

Bob