Too cheap....LiPo Batteries

[nathanreed]

Hi All,

I am looking at getting another couple of batteries and stumbled across this great site of cheap stuff.+ free shipping worldwide !

What do you guys think of this battery? US$27 posted
http://www.dealextreme.com/details.dx/sku.12823

Mystery 20C 2500 mHA
not sure of the burst C sorry... cant tell from the photos.

Too cheap to be true ? Im thinking of putting it on my Trex450se v2 with 430XL running T12 at 100% flat. About 3K head speed. Flying Fireball waiting to happen?

No 3D yet, just circuits... yet to take the plunge.
I have had an align battery that puffed in a couple of flights. My Flight Power 2500 is still cranking on 3 months later. 5min fligths only.

Thanks All.
N,

[Baine31]

For $27.00 why don't you buy it and test it out. Post the results here for the rest, coul dbe a great pack....but I doubt it. I think I'm going to do the same.

[AFjetmech]

The label on them is exacty like the Yuntong batteries I have. Just says "Yuntong" where thaose say Mystery. I think alot of batteries come from the same manufacturer and are just labeled for whoever sells them. I have a few Yuntongs still going strong after at least 50 flights and they were twice what those Mystery batteries are selling for. I'd try them out. I just bought a couple of the Zippy lipos from Hobby City. They also come with the Deans already on and were $29. Good enough for my lazy style of flying.

[nathanreed]

Sounds Good, I think I'll grab one and put it through its paces.
I'll post back here when It arrives with some photos and some test results.

I have an Eagle Tree logger V3 on the Heli so I'll be able to drop some Graphs too.
Thanks Guys, I'll keep you posted.
N.

[Baine31]

Lookin forward to seeing those results Nathan! :thumbup:

[nathanreed]

The Battery has Arrived. :) Deal Extreme didn't have any instock so it took a little longer than expected.

Initally I will post some Photos of the battery, size weight, comparison shots.
Then I will run it through its first charge, record it on the eLogger and post. Then run the standard wearing in process, then record a 5 minute flight doing circuits and post the results.

Inital (Storage) Cell voltages where 3.87, 3.87, 3.74

Size: Width - 34.09mm, thickness 22.16, Length 105.22
Weight: 172g

Arrived in a padded bag...
http://www.users.on.net/~nathanreed/battery/IMG_4633.jpg

Small Blister pack
http://www.users.on.net/~nathanreed/battery/IMG_4634.jpg

http://www.users.on.net/~nathanreed/battery/IMG_4637.jpg

Some Comparison shots vs a 2500mAh Flight Power, 3.5x the price. ($30 vs $110
http://www.users.on.net/~nathanreed/battery/IMG_4641.jpg

Not a great comparison, considering one is 2100 mh and the other 2500 mah
http://www.users.on.net/~nathanreed/battery/IMG_4643.jpg

http://www.users.on.net/~nathanreed/battery/IMG_4652.jpg

http://www.users.on.net/~nathanreed/battery/IMG_4658.jpg

In Heli Shots
http://www.users.on.net/~nathanreed/battery/IMG_4671.jpg

http://www.users.on.net/~nathanreed/battery/IMG_4669.jpg

vs
http://www.users.on.net/~nathanreed/battery/IMG_4664.jpg

http://www.users.on.net/~nathanreed/battery/IMG_4665.jpg

[nathanreed]

Charged the new battery lastnight : no fire which is good. Final cell voltage is: 4.20, 4.20, 4.18. My eLogger filled up (forgot to change the logging frequency) but I have some data that I'll post. Battery remained cold throughout the charging process (Align 3cell charger)

[Baine31]

Just wanted to say thanks for continuing on with this project. I look forward to seeing the flight results!!!

[Snarf]

I bought three of these packs in November last year. They each have about 70 cycles on them and perform like the day I bought them. I charge them at 3C using my CellPro charger without any ill effects. Internal resistance on the cells is not great (11 to 16 mOhms) but they give me plenty of grunt for my flying (limited to FFF - no 3-D yet).

For anyone learning (like me) they allow loads of stick time at minimal cost.

[pinchio]

I have those exact lipos.

It says don't charge above 1C. You charge at 3C!!!

Charging at that rate do you think it accelerated your resistance readings?

I also have the CellPro 10s. What a kick-ass charger.

Cheers,

Rob

[pcar993]

any feedback??

[nathanreed]

Sorry All, had a slight mishap with my Heli.... Tail Belt snapped mid air! luckily I was only doing Circuits ( i was using my FP battery, which was spectacularly ejected during the crash)


Twas a nasty crash and Can't really believe it happened. The belt looked pretty worn out... must have had the tension to high.


Have repaired the rest of the heli. Just waiting for a new belt. Common Australia Post...

Btw thanks for your comments Snarf, thats great to know, for both me and others :)


http://www.users.on.net/~nathanreed/battery/DSC00069.JPG
http://www.users.on.net/~nathanreed/battery/DSC00072.JPG
http://www.users.on.net/~nathanreed/battery/DSC00076.JPG

[nathanreed]

Charging Graph from the eLogger. Cut short sorry - the elogger filled up.
Heli should be back in the air mid week.
http://www.users.on.net/~nathanreed/battery/charging.jpg

[pcar993]

What type of balancer plug is it? Align? Thunder power?

Thanks!

[nathanreed]

Align Balance Charger

http://www.align.com.tw/shop/images/kx850143a.jpg
KX850143A New Lithium Battery Balance Charger
RCC-3CX

●Series no: RCC-3CX
●Input Voltage: AC 100-240V 50-60Hz
●Output Voltage: 2cell DC 7.4V
3cell DC 11.1V
●Output Current: 1000 mA/cell

Sure its a little slow, but it does the job. I always set a timer and disconnect when I get all green lights.

[nathanreed]

Sorry I just read your post again,

It is an Align Balance Plug on the battery.

[pcar993]

I just bought a pack today. Ill put this sucker to the test.

[nathanreed]

Ah good stuff :)
I received my new Tail belt Yesterday, fitted it last night, I will balance blades, set tracking, test flight tonight, then I'll be back into testing the new battery. Sorry for the delay. Results will be posted this weekend.

[pcar993]

How fast did you get your lipo when you placed your order?

[nathanreed]

Mine was out of stock when I ordered it, but once it was back instock it took a day or two to process and package, then it took 5-6 days to arrive on my door step :)

But I found it depends on the day, If I ordered before thursday, I would have it by wednesday the following week, If I order thursday or friday, I have to wait until the following monday or tuesday. I guess it would vary depending on where you live/customs etc.

[iflymyhelishigh]

Has anyone tried these?

http://www.dealextreme.com/details.dx/sku.12821

they have a lower C rate but have more mah??

[electricdurango]

I hope to hear these perform like AT's or TP's. You could get 3+ for 25.88 each. For the price of 1 TPv2 I could get 3 of these. Cant wait to hear the cycle reports after 50+ cycles.

[NorFlyer79]

I bought two of these Mystery batteries on eBay from a seller called shopping way (http://stores.ebay.com/shopping-way1398)

2200mAh, 25C. $50 including shipping. They came with Deans connectors installed, and a extra set of male connectors.

I flew 9 minutes, mostly FFF, and some hovering. Tried some collective "punches" as well, and there was no lack of power that I could notice. 11.32 Volts measures after flight. It also looks like they've made it a more open design, allowing the battery to run cooler. This one took 1507mAh of charge after this flight.

All in all, a pretty good deal IMO :thumbup:

[AzHeliCrasher]

Update?

[nathanreed]

Sorry for the delay guys, after replacing... well most of my heli... Im back in the air. Replaced...
Tail shaft
Main shaft
Seasaw arms and brushing
Main bearings
tail shaft
Landing skid
Blades - (&balanced them)
Tail blades
Complete tail section of the heli (boom, supports, H&V stabilizer)
Tail bock and bearings
Tail Grips and connecting shaft
Feathering shaft
Tail belt
Swash plate
Upper right frame
Canopy
Flybar and paddles
main gear,
one way bearing
auto rotation gear
Here is the elogger graph of the Mystery, mostly circuits and I threw some pretty sharp ascent's at it and it performed better than I expected. This battery is 11 flights in now. FP is at about 30.

Circuits with some steep ascents thrown in.

http://www.users.on.net/~nathanreed/battery/Mystery.jpg

Vs Flight power, mostly just circuits, no steap ascents.

http://www.users.on.net/~nathanreed/battery/FlightPower.jpg

Interesting to see the temp of the battery (probe strapped to side of battery)
a little cooler than the FP but not much.

I am charing the Mystery now with the elogger attached, will post when its complete.
Enjoy.

http://www.users.on.net/~nathanreed/battery/mysteryCharge.jpg