7 ms·
While it would work, it would be horrible marketing for EVs.
by gambler 8y ago
While it would work, it would be horrible marketing for EVs.
- sokoloff 8y agoWhy would someone reasonably care what equipment is onboard the service trucks? I've never inquired as to what's inside the Mercedes Sprinter vans they use for roadside assistance when considering buying a Mercedes.
- masklinn 8y agoIt would be great for actual roadside assistance though, fuel is way more energy dense and energy specific than the best batteries, using batteries would mean way less ability to actually assist. An alternative would be an SMR (and possibly a bank of caps) but I don't think any of the currently working or even close to working designs would fit on a regular trailer (the KLT-40S seems to be the lightest working SMR at 80t with water, the rest is 150~1500t).
- Reason077 8y agoA battery would work just fine. DC-to-DC transfers are efficient, and fast.
- masklinn 8y agoBattery would greatly limit the amount of assistance which can be provided, and greatly increase the trailer's weight.
- Reason077 8y agoA diesel generator set that can output 100kW continuously for fast charging starts at around 2000kg / 5000lbs. You can fit a lot of battery capacity for a lot less weight that that!
- masklinn 8y agoYou really can't. The 85kWh Model S battery pack is more than 500kg.
- Reason077 8y agoAn 85kWh pack can easily sustain, say, a 100kW discharge rate. You could even double that and still be half the weight of the generator set [^]. A 10 minute charge and you'd have topped up the stranded vehicle with 16kWh, enough for 50 miles or so travel to get home or to the nearest fast charger. And you'd still have plenty left in the pack in the unlikely event of further callouts. [^] (Modern EV packs already have significantly higher energy density than the old 85kWh Model S, by the way).