waste of time. don't bother.

[liveforphysics]

I went through my giant LiPo pile looking for what had the best energy density. I've got an older 20C zippy pack 2.2Ah, 3S, that really has 2.2Ah at a reasonable HVC/LVC, and it stores 1watt-hour for every 2.55cc's of volume it takes up. Most other packs were in the 2.8-3.2cc's per watt-hour range.

This pack is claiming 2.19cc's per watt-hour.

About 12% better than the highest energy density LiPo that I've got laying around the house, but not out of the realm of possibility.

I'm going to buy the 5 sample minimum and try to quantify some actually capacity and c-rate numbers. The problem is, I'm moving right now, and i don't know what my new address will be in Cali, so I'm not sure how I should have them shipped.

 

[liveforphysics]

Also, if shipping is perhaps $100 for 5 packs, that makes them $0.29/watt-hour. That's absurdly cheap.
My concerns mirror John's though, I've got to wonder if they use the old-school LiPo chemistry that was only good for a few hundred cycles before performance gets poor.

Gotta think positive though until we can get some to test.

-Luke

PS: This means you could build yourself a 1.8kw-hr pack that weighs 19lbs, occupies only 4L of space, and costs ~$500. That is like a dream come true for DIY ebikers.

 

[maydaverave]

If these are actually 20ah and last for about three hundred cycles then I would definitely buy two for a 44v 20 ah pack even if the listed weight, c rate, and dimensions are on the optimistic side 8)

 

[999zip999]

3 HUNDERD CYCIES ?

 

[fizzit]

I found a video where they show all the real specs of this battery and use it in an ebike! 8)
http://www.youtube.com/watch?v=dQw4w9WgXcQ

 

[liveforphysics]

I found a video where they show all the real specs of this battery and use it in an ebike! 8)
http://www.youtube.com/watch?v=dQw4w9WgXcQ

Deek.

 

[Ricky_nz]

I found a video where they show all the real specs of this battery and use it in an ebike! 8)
http://www.youtube.com/watch?v=dQw4w9WgXcQ

"This video contains content from Vevo, who has blocked it in your country on copyright grounds."
:x This %^&*$ needs to die.

 

[Anonymous]

Can you download the .FLV and upload it back on youtube.com? I'm installing tor right now to gain access to this

I found a video where they show all the real specs of this battery and use it in an ebike! 8)
http://www.youtube.com/watch?v=dQw4w9WgXcQ

 

[Anonymous]

2 of these and you've got 200A continuous 72v...
in 2s2p and that's 144v 20ah..... that's enough to move a car for $1,200, major savings on weight compared with lead acid.

The shipping via EMS is usually $80 (it actually costs them $50 to ship it...). So works out at $380, in pounds that's 253... pretty good deal.

This is another gold seller, I sifted through the rest of the sellers, seems to me like these guys supply quite a bit and in large order quantities usually but are willing to ship individual battery packs. I don't know much about these guys, but from what i can tell it's worth investigating if they're for real about the continuous ratings.
I think they are because:
1) they mentioned propelling electric cars
This requires a lot of amps for the torque necessary.

I wonder if the dimensions make it slot straight into one of those standard 'spaces' behind the seat where the 'silver / aluminium nimh' battery usually goes, so it doubles the power, and fits right into a normal 'slow' electric bike. For someone who wants to experiment with a battery-less bike (like me) this can prove fun.




I don't have the cash to buy both lipos and this, so if someone is willing to deal with them (and get your money back if they've lied) then that's the right step, more voltage = more efficiency by square of 2 than lower voltage, this is more performance for a slight weight gain.

If it saves pack building, then we can be modernizing our drive equipment and other things without having to worry about the battery task, also according to NEMA 72volts is the highest voltage you can work with without getting electrocuted.

Rated Voltage:72V
Capacity : 10AH
Max. Charge : 20A
Max. continuouse discharge : 100A
Peak discharge 200A

Features :
1- Built in with BMS :
a- Programble thresholds and monitor each cells' voltage, cells' group
temperature, and current.
b- Programable cell balance during charging and/or after charging.
c- Normal "open" relay switch out put for charge and discharge protection:
* Charging protection: swtich turn to "close" when cells' over voltage, over temperature,
over current not within preset thresholds.
* Discharging protection : switch turn to "close", when cells' under voltage, over
temperature, over current not within preset thresholds

Charging protection relay out put switch should connect to charger's trip circuit, and
discharging protection relay out put switch should connected to controller's trip circuit
to stop charing and discharging as required above.

Switch rating : 60V200mA
d- Computer diagionse : to read cells voltage, protective status, set parameter, and
calibration voltage and current group by group.
2- High rate (10C continuous) discharge and fast charge (2C).
3- 2000+ full depth of discharge cycle life .
4- High energy & power density .
5- Rugged construction (plastic case + cell mounting frame) battery pack housing.
6- 10pin socket on case with dust cover ;Protective signals of each pack from 10pin socket
could be connected with other battery packs with same votage / capacity packs in series /
parallel.

built in bms, looks like a big SLA battery, weighs quite a bit, but then it's supplying 72volts 10ah.... for an ebike fanatic or overvolter this is the right stuff.

The continuous and peak discharge make this one a seriously good bargain alternative compared with standard ducttape 1c's.

http://www.alibaba.com/product-tp/106192116/72V10AH_LiFePO4_Battery_pack.html

 

[aaronski]

I'm going to buy the 5 sample minimum and try to quantify some actually capacity and c-rate numbers. The problem is, I'm moving right now, and i don't know what my new address will be in Cali, so I'm not sure how I should have them shipped.

I'm sure lots of folks here would be happy to receive the shipment for you. If you're headed to the SF area, I'd take the shipment, or Lyen, or Methods- actually, Methods might blow them up before you get a chance to...

 

[Anonymous]

Just to let you know..
You Don't have to buy the 5 minimum order (unless ofcourse you want 5), just send them money for two, here's the invoice i got. You guys are a lot better at 'testing' batteries than I am ( i refer to LFP destruction video).

http://uploading.com/files/1e94cd33/quotation%2BPI-ECY-101013062.xls/


There's also a 72v 10ah 100A sealed lifepo4 (200A peak) that someone who's into lifepo4 can test

http://endless-sphere.com/forums/viewtopic.php?f=14&t=23051&p=335388#p335388

there's no way i'd destroy these batteries

I found a video where they show all the real specs of this battery and use it in an ebike! 8)
http://www.youtube.com/watch?v=dQw4w9WgXcQ

Deek.

 

[markobetti]

For all i know , this is a pack built with headway batteries. I have the same case for 72v20ah battery but two times ticker. Ask them to send you the info on cells inside and i bet you ll see that there are headway packs inside. Also the raiting on continuous amps are headway bms raiting for 72v10ah ( headway built in bms is 100 continues 200 peak) . i ll show you : http://img191.imageshack.us/img191/3671/056e.jpg
I usually dont trust suppliers without info on their company , especially on alibaba..
Anyway good luck ..

 

[Anonymous]

The best part about these (for me) is their size, I found how to make them safe in the event of a crash they slot into 2.5" squared aluminium tubing, they fit into standard aluminium square tube boxes with plastic endcaps. Could even drill screws into the sides of it to hold the caps in place.(aluminium is thick on this one).
This is a standard size that'll fit all of the batteries mentioned above (including the biggest one, 22.2v 20ah)

I also figured out a way to build a 'dumb balancer' out of their B4 chargers.

look at this http://www.esky-heli.com/imaxrc-b4-pro-lipo-balance-charger-471026-p-11284.html?cPath=81_220

This is a dumb balancer, one that can work with up to 4series, so it would work with 14.8v packs, three of these, and 3 switch mode power supplies.

This is their catalogue for all their chargers http://uploading.com/files/1f9cmff7/NEW%2BBalance%2BCharger----November.xls/

I'm all excited about this now

thanks!

 

[Anonymous]

Same thing as the 72volt one, but higher voltage, I guess it can be recharged using a standard 240volt to 110volt DC 5A transformer with some tweaks
http://www.alibaba.com/product-tp/106192084/96V10AH_LiFePO4_Battery_pack.html

 

[andreym]

Same thing as the 72volt one, but higher voltage, I guess it can be recharged using a standard 240volt to 110volt DC 5A transformer with some tweaks
http://www.alibaba.com/product-tp/106192084/96V10AH_LiFePO4_Battery_pack.html

i belive those 96v are nominal voltage
and will be like 32s lifepo4
so freshly-charged it`ll be like 116volts
and it`s pretty high for 4110 fets

 

[sangesf]

Hell.. If they're as good as they say (or even close) I'd say a group buy is in order..
FYI, I'm in 33467.

 

[Nader]

thank you a lot Nader
do you use your tongxin at 36V ?
do you get the same speed from the cute motor ?
do you find differences between them ?

bye

yes my tongxin is 180W 36V motor. I get the same speed from tongxin and the mini front cute (1,6 kg qrf-85sx), but the tongxin is much quieter. :wink:

so long
Nader

 

[Anonymous]

thanks, did not realize these were nominal voltages

Same thing as the 72volt one, but higher voltage, I guess it can be recharged using a standard 240volt to 110volt DC 5A transformer with some tweaks
http://www.alibaba.com/product-tp/106192084/96V10AH_LiFePO4_Battery_pack.html

i belive those 96v are nominal voltage
and will be like 32s lifepo4
so freshly-charged it`ll be like 116volts
and it`s pretty high for 4110 fets

 

[Andje]

how is this thread not more popular? batteries are the impediment; every thing else is just innovation. I'm surprised there hasn't been more interest in this potential 1/3 price situation, but i'm new to ebikes maybe i have no perspective.

i emailed the company as well asking specifically about cycle life, they sent me back the exact same catalogue, im a little worried about that since they seem to have emailed me back within 8 hours and had reasonable engrish... the fast turnaround time would indicate professionalism, and for rc batteries theres no way that the batt lifetime wouldnt be in the top 5 things on your list of things to ask as any potential consumer. Why wouldn't they address a direct question that should really be part of the stats listed on the catalogue... and they list it there on alibaba for the lipofe4
im prbly gonna order three anyway though, and frankly at the sample price if they last a year and aren't a hastle it would be worth it.

 

[texaspyro]

how is this thread not more popular?

Because we've all been there, done that. After a while, one's ass just gets too sore to bother with whatever snake oil is being peddled. AKA, we'll believe it when we see it. Hopefully, we will be proved wrong... yeah, right, like that's gonna happen.

If they could actually deliver on those specs, the world would have already beaten a path to their door and the price would be twice as much and they would still have more business than they could possibly handle and the price would go up even more. Lather, rinse, repeat until supply reaches demand.

 

[Andje]

fair enough

i choose to remain hopeful; your redaction reads like a dull shade of sad grey however, i was not trying to be naive just curious. I actually tried to find something out instead of just counting on history to repeat. I meant no offense; if it's just us noobs that would be interested im still surprised more of us weren't.

besides, everyone counted on plasma boy junior to be vapor by now

 

[liveforphysics]

Some of us all ready have shelfs packed with batteries that promised amazing specs, and then delivered something little better than a paper weight.

But, I still buy a sample or two of everything, just to be sure.

 

[cord]

I sent an email asking for cycle life, 100-150 was the response, which seems awfully low. Of course they're most likely assuming these will be used in an RC environment. In an ebike where you generally control the HV/LV better, they might last a lot longer. Someone needs to test these cells!

 

[todayican2]

Cant wait to hear more about this one!

 

[dnmun]

sounds like it has the O2 micro BMS, and 24S of the prismatic cells. very modular, but where is the charging plug?