If they are really matching cells it would be some major sorting operation. They'd have matched stock sorted. Any cells that couldn't be matched for a set would sit until something came along that matched them.
I suspect this is further than they go. But I hope that I am wrong. All I have seen is voltage check + IR check, I do hope they do more, but I haven't seen evidence, or seen any supplier
explicitly and directly state that they match beyond this. Maybe some test and match capacity, it seems that this is what Deligreen is implying. I believe Deligreen is a larger reseller than those we often deal with, its possible they have greater capabilities or more efficient processes, but I wouldn't assume it without some evidence or at least assurances.
My comment was pure speculation. But I am fairly sure there is no way to match cells without mixing them up It wouldn't be called matching if they didn't mix them up. It would just be called testing.
Possibly yes, though in theory cells from the same factory, batch, and date stand the best chance of being well matched.
But since the resellers are not getting and matching batches of new cells off the line, I'm sure mixing and matching is the norm.
And the videos they make with your name on it wouldn't have anything to do with that. I don't know what all the testing they claim to do is. They said it took days to do mine.
It would be interesting to know what testing Deligreen does, or claims to do. It sounds like they
may capacity test the cells if the testing really takes days. On the other hand, maybe it just takes them a few days to get around to making a video with the multimeter and IR readings. Did they spell out what/how they test in any of your correspondence.
Of course, you would think if they were going to capacity test, they would do this as they receive the cells, this would be much more efficient for them (if they are capacity testing all cells) and allow binning and faster shipping.
Even if they lied about matching cells they would have to mix old ones with newer ones just so it looks like they are matching them.
I hope they would not do this (lie, but also mix and match to make it look like they are matching), the extreme best practice for applications where matching is very important is tightly matched cells from same factory, batch, date and if possible in cronological order (serial number). At least this is what I learned from Nordkyn and Marinehowto. This is overkill for most of our applications, and can't be done by the resellers we buy from or at the price we pay. But point being, they would be shooting themselves in the foot if they mixed cells around to pretend they are matching.