waste of time. don't bother.

Status
Not open for further replies.
Hey guys, i bought some of these batteries when they were first posted on the forum and have been playing with them since. They are perfect for me as i will normaly only be using them to go to work and back(20km max) so thats only about 50% duty or less. But with the size for the price it ment that i could still have the range needed to do all sorts of extra stuff with out needing to charge up in the middle. Atm i am charging with twin meanwells with a small single HK charger to balance 1 pack each night, is working great for me. Charging to only 4V per cell and at most discharging to like 3.6, normaly only 3.75.

Considering everyones comments about the charge cycle life of these batteries i think for this sort of light use with the odd full use the batteries should last me a few years :mrgreen:
 
Bluefang said:
Considering everyones comments about the charge cycle life of these batteries i think for this sort of light use with the odd full use the batteries should last me a few years :mrgreen:

Highly likely too IMO ... keep us updated on any happenings please :)

Best of luck

KiM
 
latest fixing worked. I used a hardened machined titanium chain ring. and had to modify it to fit the cyclone freewheel chainwheel that I purchased. I don't think this will break. also, a reduction from 24 teeth to 22 teeth in place has helped the acceleration without damaging the gear system on the bike too much.

Chain suck develops on chain rings mainly, but for some reason, it doesn't happen that often with rear casettes...i dont know why. however, seeing how i've done over 800 miles on the kit since fixing it. added below are some photographs of modifications done to the cyclone freewheel.

It did not come with a BCD that was standard, indeed, it is a five arm, that is somewhere between the 58mm and 74mm mark, i measured 65mm BCD, which is a very odd number for a chain ring to have...but i suppose that was the only option for them as the freewheel was too big to fit a 58mm, ... but then why didn't they (cyclone) make it a stock 74mm? beats me.

pictures:







FINISHED PROJECT

 
Ive got a 24V 450W Currie EZip motor running from a 24v 10ah lead acid.

I am thinking of buying two 22.2V 5Ah RC LiPo packs (£30 each) from Ebay and joining them in Parralel to make a 22.2V 10Ah pack

My question is , does a 6 cell lipo 22.2V battery have enough volts for my 24V Ezip or do I need 7 Cells?, will the controller complain about the lower voltage and cut out?

Also if i connect the lipos's in parralel , do i just join the pack connectors in parralel or do I need to do it at an individual Cell level?

The packs i have seen are 25c so i think 2 of these in parralel will produce enough current, i guess I will need no more than 30amps max

Ive used LiPos before in RC Planes and am amazed at what they can do.

thanks for you help , i am looking forward to ditching my lead acids
 
They come of the charger at 25.2 hot . You dont see 22.2 until you reach the last 30-40% of discharge. The lvc of the controller should be 21v. This should be a perfect spot to stop discharging lipos. This will bring the lipos to 3.5v a cell. I dont see anything wrong with what you are trying to do. You wont get the full 10AH maybe around 8-8.5AH because the LVC is stopping the discharge kinda early but its in the perfect spot.
 
lumsdot said:
I am thinking of buying two 22.2V 5Ah RC LiPo packs (£30 each) from Ebay and joining them in Parralel to make a 22.2V 10Ah pack

DON'T buy cheap lipo from Ebay gotto HobbyCity pick up a couple of packs of Turnigy or Zippy 6s 5000mah packs ever increasing number here using them (myself included)

KiM
 
Guys, this thread has been dead for a while, and i know some of you have had these in your hands for a bit.

Is the general verdict that these are crap?
 
Low production volumes VS 5ah pouch format, non-optimized cell shapes, and few factories that have even tried to do them. It is cheaper to get 5ah pouches made and just parallel them at the cell level. Even if one 20ah 4p cell chunk went bad, it is still cheaper than replacing a single 20ah cell.
 
The cathods and anodes are farther apart in large cells. It makes it harder for the ions to navigate across. Meaning lower C rate.

Smaller size batteries also can be cooled easier. Just keep them a bit apart and blow air on them. With large cells it's hard to get heat out of the middle of the cell. Hope that makes sense.

And what john said :)
 
i've seen your bofoeili bike and i like it very much
is it 36v motor ? how much current do you put in it ?
on your page i see only pics are there also technical data ?
do you like this motor ? does it have a low drag ?
do you have some pics during the build process?
 
ericmann2000 said:
i've seen your bofoeili bike and i like it very much
is it 36v motor ? how much current do you put in it ?
on your page i see only pics are there also technical data ?
do you like this motor ? does it have a low drag ?
do you have some pics during the build process?

hi eric!

yes this project is allready done and this eBike ist the best, which I ever drove.

bbm.jpg


It is a 350-400W very strong bottom brackets engine (Bofeili) and can be operated with both 36 and 48V.
The controller is a 15A.

Thereby is 28 mph loosely possible (with 36V) and 17% hill very easy to drive . :wink:
..and you can read and see the building process in german pedelec-forum (http://www.pedelecforum.de/forum/showthread.php?7026-Tretlagerantrieb-im-Selbstbau).

regards
 
Great build Nader! Stealthy & great looking :D

Where do you purchase your water bottle-styled battery casing? I've been searching high and low from various popular sources (conhis/ebike/bmsbattery/ping,etc) but no 1 seems to carry it

Cheers,
Raining
 
Raining said:
Great build Nader! Stealthy & great looking :D

Where do you purchase your water bottle-styled battery casing? I've been searching high and low from various popular sources (conhis/ebike/bmsbattery/ping,etc) but no 1 seems to carry it

Cheers,
Raining

hi Raining,

I took just a normal water bottle (Laken 1,5L) and built a 36V 5Ah battery with konion cells.

4295.png


4300.png


You can see the building process here < http://www.pedelec-forum.de/forum/...nakku-ist-fertig&highlight=neuer+flaschenakku>

Cheers
Nader
 
nice bikes Nader :mrgreen:

I've never seen the Bofeili motor before looks very cool!
 
Hi

Selling stuff as cannot carry on with projects at the moment.

These are good cells, matched to IR (internal resistance) and can withstand 280A continuous with barely getting warm, this is a great addition to any 48volt based controller (usually they max out at 66volts) and gives the best boost for your original ebike.

I'm looking for an offer, (no silly offers please but something reasonable with postage by Royal Mail) feel free to offer an ammount they're assembled into a triangle shape for a 20" frame.
considering these have been used 30-40 charge cycles. (once a day for a month till 5304 motor burnt out).
Originally sourced from Dewalt packs purchased from Dewalt service center.
The cells gave a really good current, but recently when I tried using the pack, I accidentally forgot to charge one series of the batteries, so it seems there might be something wrong because the voltage only goes up to 52volts now. so I blew 4 cells. :(









thx
 
Status
Not open for further replies.
Back
Top