Short primer: The polysulfide shuttling effect is a phenomenon that can occur in lithium-sulfur batteries. It occurs when polysulfide ions, which are intermediates formed during the discharge and charging of the battery, are able to move from the cathode to the anode. This causes a decrease in the overall capacity of the battery.
To prevent this from happening, a separator with a high ionic resistance is used to physically block the movement of the polysulfides, but this increases the bulk and form factor of the battery, which makes it less suitable for applications like phones and laptops.
Claim 3x the capacity of current lithium ion. That would be, what 600 wh/kg? 750? That seems unbelievable.
In short, if you are lucky enough to own a vehicle with such a battery, it needing replacement is not going to be an event that you should have to worry about for decades if you drive it normally. Which would mean doing about 14K miles per year; or about 71 years.
Petrol/gasoline 44-46 MJ/kg Diesel fuel 42-46 MJ/kg Crude oil 42-47 MJ/kg
You're already near far denser volatile chemicals, even if it isn't you driving someone else is somewhere.
EVs are much safer both in absolute numbers and relative numbers (if you consider there are far less EVs than ice vehicles). They do occasionally burn of course. And usually those fires aren't very explosive and give you plenty of time to get out of the vehicle and to safety. Fatalities/injuries are rare with this.
This article seems to have much less bullshit than most. Hope this one works.
TnT or nitroglycerin is much more dangerous in spite of much lower energy density because the energy is all in the TnT.
Of course this isn't the only consideration (the fact that TnT releases nitrogen which suddenly wants to be much bigger is important, for example), but it is a reason to hesitate around such a battery and carefully consider whether you want to throw it around at 100km/h.