One of the posters in the 70D-105D thread threw this idea out in passing, and I thought it might be worth more serious consideration.
Generally when people talk about adding batteries to a modern EV, it just isn't practical - you have to match the ~400V output, and somehow deal with safely connecting it and with managing the power flow and heating/cooling.
However, the Powerwall is different. It's already in the same voltage range, and packaged with a DC-DC converter and cooling system. The DC-DC converter is potentially an answer to both the safety and the power flow aspects - by subtle adjustments of the output voltage you can manage the energy flow from the Powerwall whatever the car is doing.
I could easily see Tesla hooking a Powerwall adapter in the Frunk into the CANBus and to the battery through the Supercharger wiring/contactors (or a new group of contactors,) thereby allowing you to hook one or more of the modular boxes in when you need it but not have carry it all the time. The firmware could be set to slow discharge/slow charge the Powerwalls, hopefully minimizing the need for heating/cooling.
If they ever get around to offering the notional aluminum-air packs we were talking about patents for a couple years ago, those could use the same interface and methodology.
Thoughts?
Walter
Generally when people talk about adding batteries to a modern EV, it just isn't practical - you have to match the ~400V output, and somehow deal with safely connecting it and with managing the power flow and heating/cooling.
However, the Powerwall is different. It's already in the same voltage range, and packaged with a DC-DC converter and cooling system. The DC-DC converter is potentially an answer to both the safety and the power flow aspects - by subtle adjustments of the output voltage you can manage the energy flow from the Powerwall whatever the car is doing.
I could easily see Tesla hooking a Powerwall adapter in the Frunk into the CANBus and to the battery through the Supercharger wiring/contactors (or a new group of contactors,) thereby allowing you to hook one or more of the modular boxes in when you need it but not have carry it all the time. The firmware could be set to slow discharge/slow charge the Powerwalls, hopefully minimizing the need for heating/cooling.
If they ever get around to offering the notional aluminum-air packs we were talking about patents for a couple years ago, those could use the same interface and methodology.
Thoughts?
Walter