Fast E.V. Charging.

Certainly (following a rather odd conversation) at least one of the makers of the electric racing cars (formula E) find themselves limited by a 1000V upper bound that they think is determined by the fact that any more would not be LV, and that would limit who can work on the car, and how, and in turn this affects how they are able to design, and the overall efficiency.  So for now they try and design right up close to 999..9V at the start of the race, and falling fast as they go round. However from a power and torque perspective they would love to hit the motors with less ampy slices of something higher pressure.


The  Silicon Carbide semiconductor devices for 3.3kV DC are readily available, and technology to scale up for making devices good for quite  a bit more is not really an issue, yes they are quite expensive, but nothing compared to a battery, and mainly because they only sell in small numbers to folk doing specialist things.


While I appreciate the rules of the racetrack are quite different, for lorries at least, I can see a similar need for a lot of horse power at the wheels, and a good electric efficiency, so a similar voltage shortage, may drive towards higher voltage batteries too.

Even if it does not, one can imagine, series charging as you suggest, much as HGVs often have double tanks, I can imagine that they will also have double batteries. In any case the LV HV threshold  is an entirely man made limit that may be an awkward one for high power vehicles - for any other load, let alone one that needs a 'flex' to plug it in, by the time we are looking at hundreds of kW, we don't normally design for an LV supply, and an article about 1000V charging cables needing liquid cooling suggests that they are already up against it, and these are the early prototypes, longer term we can expect more to be needed not less.

Putting the regs to one side, it may be nicer as we already allow and use 3 phase supplies  at 230/400  and 400/690  to extend the rule of 3 concepts to permit  690/1200 or even 1200/2060, and keep the 'fuel pumps' as simple transformers, and allow the vehicle to sort out the specifics of charging best to suit its on board batteries.

Certainly (following a rather odd conversation) at least one of the makers of the electric racing cars (formula E) find themselves limited by a 1000V upper bound that they think is determined by the fact that any more would not be LV, and that would limit who can work on the car, and how, and in turn this affects how they are able to design, and the overall efficiency.  So for now they try and design right up close to 999..9V at the start of the race, and falling fast as they go round. However from a power and torque perspective they would love to hit the motors with less ampy slices of something higher pressure.


The  Silicon Carbide semiconductor devices for 3.3kV DC are readily available, and technology to scale up for making devices good for quite  a bit more is not really an issue, yes they are quite expensive, but nothing compared to a battery, and mainly because they only sell in small numbers to folk doing specialist things.


While I appreciate the rules of the racetrack are quite different, for lorries at least, I can see a similar need for a lot of horse power at the wheels, and a good electric efficiency, so a similar voltage shortage, may drive towards higher voltage batteries too.

Even if it does not, one can imagine, series charging as you suggest, much as HGVs often have double tanks, I can imagine that they will also have double batteries. In any case the LV HV threshold  is an entirely man made limit that may be an awkward one for high power vehicles - for any other load, let alone one that needs a 'flex' to plug it in, by the time we are looking at hundreds of kW, we don't normally design for an LV supply, and an article about 1000V charging cables needing liquid cooling suggests that they are already up against it, and these are the early prototypes, longer term we can expect more to be needed not less.

Putting the regs to one side, it may be nicer as we already allow and use 3 phase supplies  at 230/400  and 400/690  to extend the rule of 3 concepts to permit  690/1200 or even 1200/2060, and keep the 'fuel pumps' as simple transformers, and allow the vehicle to sort out the specifics of charging best to suit its on board batteries.