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Vectrix Battery Analysis and Reconditioning
Submitted by Mik on Thu, 07/02/2009 - 03:58
A description of the Vectrix battery including capacity measurement and reconditioning can be found on Endless Sphere at: https://www.endless-sphere.com/forums/viewtopic.php?f=14&t=6277
Here are some snippets:
Green: Average cell before reconditioning
Red: Best cell in pack before reconditioning
Black: Average cell after reconditioning
I can now identify the bad cells much quicker - that's the good news.
The bad news is that I can identify them because they have bulged, probably due to excessive internal pressure.
It is not very obvious, but once you know about it then it can be felt (more than seen) on the narrow sides of the cells. There is a very high correlation between cells which tested initially as having poor capacity at 20A, and the bulging. A few cells have a little bit of bulging although they do not have a very low capacity. I have not checked it obsessively enough to be sure, but I feel very certain about it. The correlation is close to 100%.
I managed to run my fingers along the sides of the 9- and 8-packs of cells and could identify the cells that tested low for capacity at 20A! I can literally find them with my eyes closed.
And find (a very few) more that the CBA2 missed....
Part of the good news is that a Vectrix owner with just a few cells gone bad can rapidly (in a few hours) identify them, rather than spending weeks testing day and night, and then replace them.
That only helps if you can get replacement cells, of course.
I have also deciphered the battery labels on the side of each cell:
C3008061221000125 means, for example: Capacity 30Ah Date of manufacture: 2006-12-21, number made that day: 125