I think a few words of explanation will be helpful as well.
1/ Where a cell degrades and falls to zero volts or less.
Less than zero relates to a condition whereby the cell becomes a closed circuit in its own right. A battery of any type will have anode and cathode, this condition is permanent, they cannot become interposed. The anode will always be the anode, cathode will always be the cathode.
2/ Short circuits.
There is no such thing as an absolute short circuit as every current carrying conductor will have a resistance value. Even the spanner dropped across the terminals of a lead acid car battery by a careless mechanic is not an 'absolute short' regardless of the spectacular effect, it will have a resistance value.
A cell that becomes a closed circuit of whatever R value will conduct or draw current from other cells.
As said, a cell that becomes a closed circuit, (in its own right not as part of a series array, I am trying to explain this in simple terms) will draw or conduct current from the other cells which will be a product of its resistance and the voltage being applied as governed by Ohms Law, and the the energy consumed will be converted to heat. Every conductor has a resistance value and converts energy to heat. The lower its resistance once it becomes a 'closed circuit' the more current will pass and the more heat be generated. You can see where this is going.
The paper is in effect an attempt at a hatchet job on electric cars which it explicitly references. My Exon joke may well be a true word spoken in jest. The power banks of electric vehicles are electronically managed and monitored with adequate safety considerations. Manufacturers of cells such as Tesla and Sanyo Panasonic maintain stringent quality controls.
My avatar is a poor likeness.