[space_rock]

Believe it's the battery short and discharge that starts the heat and fire. And to prevent damaging the batteries they ship them 50% charged

Newer electric cars are LiFePo and don't catch fire and are less dangerous

[layoric]

While LiFePO4 is a safer chemistry than batteries using NMC, they can absolutely still catch fire. The only Lithium based chemistry that I know off that you might be able to describe as "don't catch fire" is Lithium Titanate/Titanium Oxide (LTO), but even then, in a bad enough situation I believe it will still ignite though briefly but won't sustain. LiFePO4 will still ignite and sustain a fire from the demonstration videos I have seen.

I don't know enough about the "Blade" battery chemistry but early info I have seen seems to indicate a very high level of safety as well, more so than current LiFePO4 setups.

[space_rock]

The blade battery is LoFePO4 and the video released show them only heating and smoking after being punched and short circuited

Well if you watch YouTube most nail puncher tests of LFP don't catch fire. There is one video were someone hammers two holes in the battery and it catches fire