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The dead cell likely did not short, as there are 15ohms of internal resistance and the dead cell is randomly located in the module (i.e., it is not in the same/similar location between the affected modules).
The IC’s transistors have high internal resistance
Source: analysis by hardware/electrical sub-teams
There are no visible signs of damage to the dead cells.
Note: there is some corrosion on random cells in an over-discharged pack, unclear if it is also present in normal-charged packs. It is present on the 2 dead cells and on cells with a functional voltage, indicating that corrosion is likely a separate issue and unrelated to the random dead cell in each module.
The dead cells are severely undervoltaged and act like capacitors.
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