I worked a whole winter on development of the Eco Friendly Rebuild so I could offer a low cost alternative for complete rebuilds or new replacement.
The most difficult function was developing an accurate way to determine the difference of a shorted cell and a cell that was reusable. Once I worked out the procedures of testing I offered the rebuild and noted in the offer that most battery packs deemed unusable had only a couple of bad cells in the mix.
For the first year the success rate on rebuilds were excellent with less than one percent of the packs being returned for repair. That percentage still exists today but the amount of dead cells in a pack has gone from a couple to the whole pack. I still am producing Green rebuilds and feel confident in the markets success to keep pushing forward however the large supply of surplus used cells is nearly depleted.
Most people that use their head for more than holding up their hat have figured out the value of my (Green)offer and have taken advantage of the program and have used this offer rather than a complete rebuild.
What this has done is diminish the amount of usable cells that were gleaned from complete rebuilds that is required to keep my program going.
I will have to designate the amount of bad cells that can be in a battery pack to qualify for a Green rebuild and require complete rebuilds on those packs that exceed that number. This should bring more usable used cells back into the program.