Super 14.4 v batt.pak for Cordless drill

[Norm]

Gradually figuring out 12 cells for 14.4 getting them to perform as they should
think i"ve got it figured out.
My configuration consist of 3 cells across by 2cells high  2 layers

Now to make it twice the capacity I'll do this....

It'll work for me lot cheaper than NiMh
besides I can take these 2 paks and put them in series to drive the treadmill
motor on the E bike that I'm planning on making..
@95 volts produces .75 hp.
so 28-34 volts about .25 hp. ?

Okay Bruce?
I charge each of the 1 paks with PedPower. 11 volts to start 17volts after 20 minutes with 10 watt/hrs
Ah reads .533...after 20 minutes rest (for the battery) it reads like 16.2 .
What rate of charge is that? and is that too fast....(don't say it's too slow....cause I can't
go any faster I can go slower rate by paralleling them.
Norm.

[JW]

That is awesome...

I remember from the "pub" awhile back, when there, we were having problems, "uploading pictures to the forum".

The green paperclip means the forum is hosting the image, and it tends to be more reliable than "photobucket" lets face it, we expect more here. As an aside, we are trying to upgrade the board somemore.

Norm! I am very pleased to see that you can upload, nice quality picture's with the current arrangement...

I think its great if you guys get addicted to "pedal power"  

NICE PICTURES!!


JW

[taylorp035]

Well, how many watt hours do you have?  I guessed 45 Wh's, but I may be totally wrong (1.3v*3ah*12cells). 10 Wh / (20/60) = 30 watts.  30 watts/ 45Wh = 2/3 C.  If they came from a drill battery, I would think this is ok.  Most battery chargers take 1-2 hours or 1/2 - 1 C.  But then again, my AA nimh cells don't like much more than 1/4C.

The cell voltage can rise to a pretty high level while charging.  17/12 =  1.41v / cells , which is total acceptable.  Even 1.5v would be ok IMO.  With my windmills, I pushed that to 1.6v, but putting 15-30 watts into 4 AA cells isn't a good idea.

[Bruce S]

Norm;
 Sorry for the delay, family in Joplin has our attention right now.
I did the numbers and the fact that your batt-pack is resting at 16.2 for 12 cells means they are at 1.35V/cell which is near perfect for long term
The charging rate is okay too, , might see if you can do 30 minutes if the batt packs get used a lot, you can slow down to .370 ish for 30 mins. The .533Ah is running the charging rate at about C5, which is okay for a short period of time like the 20mins you're doing.
THIS is all based on the 14.4Vdc 2.6Ahr that I think is where this build is rated.

ONCE again I have to say how well made those are.
I'm testing a building up another box of batteries for you. the e-bike will need them.
Have fun
Bruce S

[Bruce S]

Well, how many watt hours do you have?  I guessed 45 Wh's, but I may be totally wrong (1.3v*3ah*12cells). 10 Wh / (20/60) = 30 watts.  30 watts/ 45Wh = 2/3 C.  If they came from a drill battery, I would think this is ok.  Most battery chargers take 1-2 hours or 1/2 - 1 C.  But then again, my AA nimh cells don't like much more than 1/4C.

The cell voltage can rise to a pretty high level while charging.  17/12 =  1.41v / cells , which is total acceptable.  Even 1.5v would be ok IMO.  With my windmills, I pushed that to 1.6v, but putting 15-30 watts into 4 AA cells isn't a good idea.

Taylorp035:
Sorry somewhere we forgot to re-include the details for these cells.
These are NiCd 1.2V 1300mA sub-c sized cells. These are used, some more than others
Not sure which batch Norm is using or re-using , but mostly the ones he's rebuilding, range from being only 70% of original 1300mAh up to 100%.
These are better suited to a C/10. C/5 is really good for hard working packs, but not long term due to possible internal heating.

Hope this helps
Bruce S

[Norm]

Bruce ....Like I said I could parallel 2 paks 14.4v-1.3 would change that rate from
C5 to C10 ??
When I pedal charge these no danger of internal heating ....seems like I'm the only
one gets heated up.....

Thinking of testing these out by hooking up to a treadmill motor put a little brake band
on that flywheel to adjust the resistance....with the WattsUp meter I can find how many
watt hours a certain battery holds....could you give me an idea what would be a good rate of discharge
from x1 voltage to x2 voltage ?

 Looks neat to watch a treadmill motor spin with 2 of those 14.4 batteries in series
spinning it ....
 My air compressor has a belt same number of grooves as a treadmill motor pulley
has ....pulley is only 1/2 the size of original but should be fun to hook up48 volt battery
to treadmill motor....

 Norm

[Bruce S]

Bruce ....Like I said I could parallel 2 paks 14.4v-1.3 would change that rate from
C5 to C10 ??
When I pedal charge these no danger of internal heating ....seems like I'm the only
one gets heated up.....

Thinking of testing these out by hooking up to a treadmill motor put a little brake band
on that flywheel to adjust the resistance....with the WattsUp meter I can find how many
watt hours a certain battery holds....could you give me an idea what would be a good rate of discharge
from x1 voltage to x2 voltage ?

 Looks neat to watch a treadmill motor spin with 2 of those 14.4 batteries in series
spinning it ....
 My air compressor has a belt same number of grooves as a treadmill motor pulley
has ....pulley is only 1/2 the size of original but should be fun to hook up48 volt battery
to treadmill motor....

 Norm

Norm;
 Sorry, thought the pic had it at 2.6Ahr already, YES you can do that. At least it works for me I have a Ghurd controller on mine and have in the past adjusted the charging by adding extra packs in parallel. In the commercial world this wold not be a good idea, but since we aren't charging these for hours on end there's little problem with them over heating.
With that pulley you would get a higher speed and lower torque with the pulley on the treadmill motor.
I do like the idea of seeing your work doing work, self satisfying isn't it
Cheers