Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
Quite a mix there, the lower the IR the better BUT they have to be tested at same voltage & state, measuring them in storage voltage is fairly pointless.What IR range is normal?
Since there's no QR code, I looked at the battery to know more, and the only thing I can find is that at the bottom of the battery there's a marking: T2, T3, U2, D1. I don't honestly know what that means, maybe that's the version of the battery.
That's pretty much what they did as April Cao from Deligreen said it's too many.
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Get a YR1035+, same may ve available from US stock. BTW, Air Expressing a small thing like that is not that scary... if must.
Next, you'll want to parallel these cells and top balance them, take them out to 3.60-3.65 and saturate the buggers till they take 1.0A or Less. Let them settle in parallel for a couple of days even, check the string voltage, will likely be around 3.350-3.400, don't be shocked ! Pending on how fast you get the 1035+, once you have it, Top Balance again. allow to saturate, then settle in parallel for 1 hour, then test cells, allow another hour & retest. You can dismantle the parallel set if you wish (your call if screws or welded studs or...
In the end, you'll want to group the cells by their IR, the "IR" that counts most is actually exactly at 3.200Vpc (Nominal Operating Voltage) as that is the median of the working voltage range.
Some of these may be older stock that have been sitting somewhere, once they've had some charge & discharge their IR's may come back slightly different. I've seen this myself, more than once.