Look what the Mailman dragged in !!!

Well.. i can't really give a full report yet.

But

I had to crimp some anderson's on one of the bricks pronto and give it a try . :wink: You know.. can't get a toy like that and let it sit. no way..

Hooked up the DB to my Folding bike, and went for a rip.

38.8v as shipped.

All i can say is... WOW... to see 20 amps on the DB and nothing but a 2v drop !!!!!!!!!!

She's on the charger now.. i need to try this again on a full charge !
 
Are those prismatic li-mn cells in there???
...
Big, rectangular emoli's -- oooooh! This is like a vicarious Christmas!
 
xyster said:
Are those prismatic li-mn cells in there???
...
Big, rectangular emoli's -- oooooh! This is like a vicarious Christmas!
Click to expand...

Sure looks like it, I have no clue if the inside of the metal cases contain pouches or if the case is the cell itself, will try to find out.

Nice and compact tho, no wasted space from cylindrical cells, they use the same darn RCA plugs that you see on many other packs.. i absolutely hate those.. for one.. exposed metal.. 2 is that they spark when you conect them.. don't like that. I will replace with Anderson's shortly.

I just finished charging, took 2.5 hrs to turn one of the 2 lights on the charger green. The packs arrived without any documents or instructions etc.. this is something i'm gonig to recomend to Andy.

I checked the discharge wires for pack voltage every 30 minutes or so, started charging at 38.94v, 2hrs later was exactly 42.0 .. i kept checking frequently and the light came green at 42.3v and then the power dropped off to 42.1 while still on the charger.

The 2nd light on the charger stays red, I do not know the significance of this yet, the writing is in Chinese or Taiwanese.. not sure. lol..

More to come later.
 
I need to fit a pack into a case that's shaped like the scoop of a spoon - a slice off the side of an ellipsis or ovoid...
Like this:
1347-05.jpg

...but longer and skinnier.

The deck of a kick scoot.

Curious how easy it'd be to break up this pack to "flatten it out"...

Basically a pack can be two-feet long, but needs to be as thin as possible...

Better to ask Falcon for a custom build?

tks

Lock
 
very nice, looking forward to your lipo review to see how much you can get out of that 20ah lipo before it cuts on lv, I assume it has a BMS? good luck with it, watch the usual naysayers diss it before you have even tried it though :roll:

knoxie
 
Lol.. you been gettin alot of Diss have you ?

I just got back from a quick 1.7ah ride on a full charge, and OH MY GOD !

10 amp draw = 0.5v sag !!!! incredible !

Yes, it has a BMS, i'm waiting on some specifics, but it's supposed to be a Ballancing BMS with all the bells and whistles.

It's gonna to be hard going back to Nimh after this.

And i still have a LiFe 48v 25ah pack on the way !!! Can't wait to try that out !
 
knoxie said:
very nice, looking forward to your lipo review to see how much you can get out of that 20ah lipo before it cuts on lv, I assume it has a BMS? good luck with it, watch the usual naysayers diss it before you have even tried it though :roll:

knoxie
Click to expand...

Since the lithium-manganese chemistry is different from lithium-cobalt (both ion and polymer), with it's own set of characteristics (safer, slightly higher nominal voltage, better discharge rates, 100% discharge possible, lower energy density, etc...), seems to me calling it lithium-polymer is confusing (even if these apparently prismatic li-mn cells employ a polymer).

http://www.batteryuniversity.com/partone-10.htm
" Small lithium-ion packs with spinel (manganese) chemistry containing one or two cells may only include a fuse as protection. Spinel is more tolerant to abuse than cobalt and the cells are deemed safe if below a certain size. "

http://www.batteryuniversity.com/print-partone-5A.htm

"The widely used cobalt-based lithium-ion has drawbacks; it offers a relatively low discharge current. A high load would overheat the pack and its safety would be jeopardized. The safety circuit of the cobalt-based battery is typically limited to a charge and discharge rate of about 1C. This means that a 2400mAh 18650 cell can only be charged and discharged with a maximum current of 2.4A. Another downside is the increase of the internal resistance that occurs with cycling and aging. After 2-3 years of use, the pack often becomes unserviceable due to a large voltage drop under load that is caused by high internal resistance.

In 1996, scientists succeeded in using lithium manganese oxide as a cathode material. This substance forms a three-dimensional spinel structure that improves the ion flow between the electrodes. High ion flow lowers the internal resistance and increases loading capability. The resistance stays low with cycling, however, the battery does age and the overall service life is similar to that of cobalt. Spinel has an inherently high thermal stability and needs less safety circuitry than a cobalt system.Low internal cell resistance is the key to high rate capability. This characteristic benefits fast-charging and high-current discharging. A spinel-based lithium-ion in an 18650 cell can be discharged at 20-30A with marginal heat build-up. Short one-second load pulses of twice the specified current are permissible. Some heat build-up cannot be prevented and the cell temperature should not exceed 80°C.

The spinel battery also has weaknesses. One of the most significant drawbacks is the lower capacity compared to the cobalt-based system. Spinel provides roughly 1200mAh in an 18650 package, about half that of the cobalt equivalent. In spite of this, spinel still provides an energy density that is about 50% higher than that of a nickel-based equivalent."
 
The most commonly used ebike ones are the 15/30/45 amp shells.
Click to expand...
Sorry if I stupid? Would some one please tell me exactly what Anderson Connectors you all using? Part numbers? There are enough connectors at http://www.andersonpower.com to make me crazy. Is that the correct manufacturer of these connectors?
 
knoxie said:
very nice, looking forward to your lipo review to see how much you can get out of that 20ah lipo before it cuts on lv, I assume it has a BMS? good luck with it, watch the usual naysayers diss it before you have even tried it though :roll:

knoxie
Click to expand...

Electric bikes?! Oh, that'll NEVER work!!

:lol:

Whenever I see a green battery pack, I always think, "Nickel Cadmium.."
Oh well, nobody said the paradigm shift would be smooth.. and just in time for your "vacation".

Looking forward to more details, Mr. Ypedal.


-S
 
I don't know how long these packs have been sitting idle, so i'm not discharging them low for a few cycles, I beleive the packs BMS will ballance the cells during charge vs discharge , I do not know this for sure yet.

How do you lithium users store your packs at night ? any special precaution ? I have a fireplace that could be useful, but from the video's i've seen, if a pack this size goes Boom, well.. you get the picture.

Sun is almost shining, I need to finish this beer, load the dishwasher, and head for the trails ! Later !
 
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