FairlyFaded
May 08, 2009, 02:03 AM
Hello. I have recently acquired a large quantity of Sony 26650VT cells which I plan on using for an EV project.
In short, I am wondering if you folks would be interested in me putting together some large packs.
Here is the story of these cells:
The cells are from a certain power tool company that had a defective battery pack design. The BMS board broke after the first charge on many of the packs. If this did not cause a failure, then the poorly welded battery straps connecting the cells were next in line. The battery packs were re designed (old designer was fired?) with 5 spot welds and a new BMS board. These cells are warranty returns. The bulk of them received no more than a few charge cycles.
Now on to the specs:
Rated Capacity - 2500mah
Tested Capacity ~2200mah
Voltage - 4.1v - 2.5v
Energy Density - 250wh/L
Max. Output - 50 amps
Weight - 90g
Size - 26mm x 65mm
Here is a forum posting about them:
http://www.rc-monster.com/forum/showthread.php?t=10178
They are similar to A123 in ways (long life, safe). They are heavier however, and are happy with 10c continuous and 20c burst, unlike the A123's 30/60c.
I would be willing to put together packs for ~ 4$ per cell.
An example pack:
10S3P: 41v, 6450mah, 2735grams. Good for 65 amps cont. 120 amps burst.
$120 USD.
This battery would work very well for any sort of large sport flier, probably not so well for a 3D.
Tell me if you have any questions/are interested.
Michael
In short, I am wondering if you folks would be interested in me putting together some large packs.
Here is the story of these cells:
The cells are from a certain power tool company that had a defective battery pack design. The BMS board broke after the first charge on many of the packs. If this did not cause a failure, then the poorly welded battery straps connecting the cells were next in line. The battery packs were re designed (old designer was fired?) with 5 spot welds and a new BMS board. These cells are warranty returns. The bulk of them received no more than a few charge cycles.
Now on to the specs:
Rated Capacity - 2500mah
Tested Capacity ~2200mah
Voltage - 4.1v - 2.5v
Energy Density - 250wh/L
Max. Output - 50 amps
Weight - 90g
Size - 26mm x 65mm
Here is a forum posting about them:
http://www.rc-monster.com/forum/showthread.php?t=10178
They are similar to A123 in ways (long life, safe). They are heavier however, and are happy with 10c continuous and 20c burst, unlike the A123's 30/60c.
I would be willing to put together packs for ~ 4$ per cell.
An example pack:
10S3P: 41v, 6450mah, 2735grams. Good for 65 amps cont. 120 amps burst.
$120 USD.
This battery would work very well for any sort of large sport flier, probably not so well for a 3D.
Tell me if you have any questions/are interested.
Michael