Another intrinsic lithium cell problem, high rejection rates have plagued their manufacture. Tesla are still currently struggling to produce consistent 4680 cells in large quantities, though hopefully Panasonic now joining them as a manufacturing partner for the 4680s will help.they use unmarked reject cells
At least they have at last got the message that using smaller numbers of larger cells is better practice, though even the 4680 is far too small. Having over 7000 cells with 24 cells in each module in each car's battery as they have been doing is design madness, when it only takes a single cell to create a major disaster and 44 people burnt to death so far.
I'm much happier with my car's 320 carefully made and tested much larger capacity cells, more safely separated into 8 cells per module.
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