Battery day implications for power walls

[Hoppi]

I am wondering what changes will happen to the power wall given the new battery tech that was announced.
It would be cool if powerwalls could be upgraded to be able to charge a CT with the same speed as a supercharger. I know that people talk about slow charging at home like that is always the expectation. But it would be nice if the power wall could trickle charge its self all day and be ready to super charge my vehicle whenever I need that. I’m especially thinking of cases going forward when 2 or more car households have all electric cars that all need charging each night. Right now our house has 3 vehicles and probably a fourth in the next couple years. Ideally they will all be EVs soon. I doubt my current home power line will charge all 4 vehicles at the same time over night to full 100% by morning commute time.

 

[Crissa]

A Powerwall isn't a charger.

But there was an interview I saw today where EVGO said they were using Powerwalls at a hundred-some charging sites to lower their impace on the grid.

So you could plug a Supercharger into a bank of Powerwalls. Wired right, it could augment the amps available from the grid.

But... Usually there's no reason to fast-charge at home. Remember, you use less power charging slowly, straight from the power source; versus from other batteries and fast-charging. The Tesla Destination EVSE can do about 12kW on its own, and that is 36 miles of range an hour. While you sleep, that's pretty much enough.

-Crissa

 

[ajdelange]

Suppose you put in a 100A breaker, wire it to a sub panel and install 4 60 breakers in that each running to an HPWC. The 100 A panel can deliver 80 A for charging total. Suppose you have 4 CT each of which is going to take perhaps 400 Wh/mi. 80 A at 240 V is 19.2 kWh/h. At .4 kWh/mi that means 48 miles of range for each hour of charging to divide up among the 4 vehicles any way you like. This is equivalent to 12 miles per hour per vehicle per hour. Enough?