One advantage GM has is by using high C rate cells such as the A123's in the Spark they can actually charge faster than a Tesla. If the Spark has say a 20kWh pack I think it could theoretically charge at 6C with a 120kW supercharger.
Yes, but we all know battery cost is a huge factor and was A123's big problem. High cost batteries are fine for compliance cars, but not for volume production. Their volume production plug-in is using LG Chem cells.
Unlike the other car manufacturers, Tesla has an approach to the technology which starts with one question: how do we replace all cars with electric cars? The rest of the strategy comes in logical steps.
A: make affordable cars people want.
Q: how?
A: make cheap batteries with large capacities.
- Provides ICE-beating performance, ride and handling.
- Covers the majority of miles with home charging
- Allows for rapid charging.
Q: What about long distance travel?
A: We'll build a network of chargers on the Interstates and major highways.
Q: Won't that cost a lot of money?
A: Not that much. We'll use up-front fees to pay for the network. We'll put the network on the Interstate and closed highways so people only use them on long trips (and charge at home for everyday use.) We'll eliminate financial management costs by making it free at the point of use. People will be using them at weekends so electricity will be relatively cheap but we can add solar and battery banks and offer grid management to offset costs further. It just has to pay for itself nationally so we can take advantage of different markets.
Q: But that's still going to be slower than gasoline, right? Some people won't like that.
A: Well, we'll keep trying to speed it up, but there are helpful factors. First, people love free. Second, you can walk away from the charger so you can plug in, go to the bathroom, get a drink or snack and your car is charging, so your perceived wait time isn't the whole time. But yes, time is an issue, especially if we get the high volumes I'm aiming for. That's part of the reason we'll make the packs swappable.
Q: swappable?
A: Yup, drive into the box, a machine removes your battery, installs a fully-charged battery and you drive off. We'll make it faster than gas.
Q: that'll be expensive!
A: Well, it won't be free, but we'll try to make it cheaper than gas, but that still gives us reasonable margin. The electricity required to do it will be relatively cheap. (You can move a car a mile on less than 0.4kWh!) But, we 'll have to come up with a simple, reliable way to move batteries in and out of an underground storage bank. Install/uninstall will be challenging, but we really want to do that for vehicle or battery assembly anyway. And if we're building battery banks for swapping and cost-management for charging we have to get the batteries in and out. Re-use makes stuff cheaper.
Q: Ok, so let's say you make it cheap, what about the fact that people won't know what pack they're getting.
A: Well, we'll keep their pack for the return trip if we can. Yeah, tricky on the logistics, including on Interstates with split rest-stops, but we'll work on it. Hopefully over time people will stop being wedded to their batteries. We'll let people keep better batteries, of course, for a fee. That'd provide a simple battery upgrade/exchange mechanism.
Q: OK, so let's say you can oull this all off. What about all of those people without a driveway or garage? Where are they going to charge?
A: Uh, where they park their car. Parking lot, street. Build something awesome and people will find a way to own it. People live in houses that were originally built a long time ago without electricity, central heating, running water, cable or telephone. Things change.
Q: Wow. Well, I think you're crazy, but I hope you can do it.
A/Q Thanks. Aren't you going to ask me anything else?
Q/A Huh?
A: Dude, I mentioned battery banks at least twice and all you can can think of is cars.
Q: OK... so what 's the deal with these battery banks?
A/Q: If we can build cheap, large batteries, put them together in banks then manage them well to maximize useful cycles we can do what?
A/Q ****! You can put them everywhere! Who'd use peak electricity? No more clock-resetting short outages or crappy wholesale rates on PV excess. You be selling them to renewable generators and to utilies to balance the grid. Maybe some people can get rid of their crappy gasoline generators. OK, now I understand your approach. Can you actually do it?
A: Maybe.
Q: I hate to say this, but I think you're giving me a slight man-crush. Do you get that often?
A: Actually, yes. I think JB gts jealous of it sometimes.
Q: Who's JB?
A: Exactly. I'm just a rich geek. He's a guy
I man-crush on.