FVEAA Forums
Battery Charging and Electronic Technology => Li-Ion => Topic started by: john.emde on July 10, 2014, 07:09:32 PM
-
Li-ion cells expand as their State Of Charge reaches or passes 100 %.
=
=
=
=
=
A cell may be damaged if this expansion is not contained (due to layer separation).
=
=
Most of the info here comes from sources unknown and was compiled from my notes and experiences over the years. Reader discretion is advised.
=
-
Thanks John for sharing your EXCELLENT compilation!!!
-
This looks like a source of some of John's compilation. This is useful in understanding the 'constraining' or 'banding' or 'side clamping' issue in more detail.
http://liionbms.com/php/prismatic_tips.php (http://liionbms.com/php/prismatic_tips.php)
-
=
After working with Li-ion cells for some time now, I firmly believe that banding the cell stacks and using a BMS is the way to go. Protect your investment.
John
-
Thanks John! i think i decided today to band my cells, because it can't be that complicated or expensive, and what would it hurt (if it wasn't needed). Seems like a simple cheap practice to follow.
Do you know what tools / supplies are needed or someplace i can have the cells banded affordably? Thanks!
i haven't decided yet about the BMS, but doing lots of research and thinking on the topic!!
-
"Do you know what tools / supplies are needed
or someplace i can have the cells banded affordably?"
Come to think of it. Yes! The guys at Build EV have the
knowledge and equipment to do the job.
Build EV (630) 740-8826
-
Included is a pic of part of the banding process.
The cells are stacked and aligned with plates at either end
and lightly pressed together to hold them in position.
Then usually 2 or more steel packing straps are tightened
around and crimped to hold it all together.
(http://www.fveaa.org/fb/cell_banding_395.jpg)
-
Nice John, thx!