Remember how Tesla had to add a titanium skid plate to prevent battery fires caused by punctures from running over road debris? Batteries in body parts likely to be damaged in collisions would be a problem.
Also, having the heavy battery down below axle height makes for a nice low center of gravity, making the vehicle much more stable.
My first though when I read about this was that it would be a mess for first responders. Fire depts across the country have had to retrain on how to handle electrical car fires. How are they suppose to use the jaws of life to cut someone out if the structural elements contain lithium batteries?
They wouldn't be lithium batteries, but I'm still wondering how these new kinds of batteries could safely deal with catastrophic mechanical failure without discharging all their stored energy in an explosion (or even just fire).
They're lithium-ion batteries with carbon fiber electrodes.
Doesn't matter what kind of battery it is though, once you start cutting through them you are very likely to short the electrodes together. Which usually ends in fires.
Depends on the circuit. Most batteries' voltage are <5 volts in default configurations. You can move the voltage boost/serial circuitry segment to the engine area. It will waste a lot of material and create redundant wiring but the overall structural voltage will be low. Low voltage does not mean it would not catch fire however.
High voltage battery packs are required due to the power required to move a car.
A 50hp engine[1] needs ~37kW which at 5 volts, that is 7,500 amps of current, which requires comically large bus bars (~200x10mm) and conversion electronics. Even at 48 volts[2], you still need ~780 amps, which still requires very large conductors.
At 400 volts, for the same motor, the wiring only needs to be sized for 100 amps, which is reasonably practical (think wire found on welders).
[1]: Let assume that 50hp is the max required steady state output for a motor in a passenger car, and lets ignore any peak/dynamic loads and HVAC as this is napkin engineering
[2]: 48v is generally accepted as the highest voltage before you really need to know what you are doing, though at these power levels, you still should know what you are doing as things like to weld, melt, become bad motors and/or explode.
It's a good thing then that the article only mentions Tesla because they aren't doing this. Tesla is not building the battery into the body, they are taking the safe way out instead. Tesla is just removing a redundant casing from around the packs.
In Australia, there are plans to manufacture batteries [1]. This is a collaboration with Cadenza, who promote their battery cells as being housed in ceramic insulation, preventing fires [2]. Here's hoping.
Er, no. Dumping 75KWH as heat requires a big resistor bank. One of these[1] could dissipate the power from a fully charged Tesla battery in 45 minutes. That's probably about as fast as you could discharge one without it catching fire. And you'd need the battery cooling system working.
Also, having the heavy battery down below axle height makes for a nice low center of gravity, making the vehicle much more stable.