R.Mitchell said:
Maybe have a thread onwhat devices everyone is finding these batteries in. I know right now most of them are coming out of laplaptops. I watched a video of batteries being taken out of a medical device pack. Is there anything on the lables that say what's inside besides it being li-ion?
Its usually easy to work these things out as all small electronics are required to list the specs, for example:
Laptop battery first result on ebay typing 'laptop battery' :
http://www.ebay.com.au/itm/Laptop-B...125414?hash=item2ee87ee326:g:IE8AAOSwLVZV3ryB
It says 10.8v 5200mah, we know its lipo / lico etc being newish laptop, that means nominal cell voltage is 3.6v
divide 10.8 by 3.6 = 3 cells in series to get that voltage.
we know that for an average 50g lipo / lico cell that 3400 is the current max density, so its not going to be 3 cells, its going to be 6 likely.
divide 5200mAh by 2 to get 2600mAh cells inside.
So you can easily work out that 6 cells of 2600mAh are required to spec out this battery.
The same can be done for nearly any battery pack not just laptops. Just do a bit of algebra and youll have the required info.
Some cells will have a nominal voltage of 3.2/3.3v but they are rare in 18650 format
To answer your question directly, the easiest place to find new lithium batteries on the cheap is ebay.
Get 6, 9 or 12 cell replacement batteries and recycle the cells from them.
You can usually get 1800-2200mAh batteries for around $2 per cell, and they are new.
Keep in mind, that most replacement batteries contain cells of a lower capacity than advertised.
I have often ordered 12 cell batts that should have 2600s in them only to find generic 1800s inside.
This is still a really cheap option though, and there is a nearly infinite supply.
I have no problem selling these cells for 1.5-2X the initial outlay after recycling and capacity testing.
kind regards
