[CamperBob2]

I'm going to assume many of you are going to disagree with me. Mainly because we come from a world with a much different customer acquisition models.

I don't disagree with path A, but the fact is, path B (and Musk's prediction that half of all cars sold will be full electric by 2032) can't possibly happen with our current power distribution system in place.

The only conceivable way that electric cars are going to take over will be if the government steps in and mandates universal form factors for swappable batteries that can be charged at advantageous times and locations and made available to drivers when and where they're needed. Any other approach to electric cars is simply stupid, and I can't begin to imagine why someone like Musk doesn't grasp that.

I speak as someone in the market for a new moderately-high-end car who would love to support Tesla... if only the whole idea wasn't so hopelessly wrong from an engineering standpoint.

[001sky]

swappable batteries

-- What is the weight, though? @450 pounds?[1]

___________

[1] edit: source of estimate - Honda s2000 with A123 li-ion was discussed in thread below, estimated battery pack weight was approx 460-500lbs. Car had more hp, though.

http://news.ycombinator.com/item?id=4536452

[CamperBob2]

Batteries are heavy no matter how you slice 'em. They will always (AFAIK) offer terrible joule/kg performance compared to a tank of gasoline.

I don't think replaceable modular batteries would be that much heavier than whatever's being done now. But yes, there would be some additional overhead, given that even the smallest cars would probably take more than one battery module.

[001sky]

The UPS and the Airplane luggage guys though will only 30 kilos (65lbs), though because of insurance/workplace comp. They wont let them lug more. at 200 kilos (440lba) you are talking splitting the pack up into 6 or 7 parts (and still be laboriously removed) or having a somewhat major operation on your car (ie, you need an Engine Hoist for the thing in one part) to change the battery. Then a forklift or something to put them on a "rack". Seems logistically like a nightmare.

That being said, the actual cells themselves are only a couple of pounds each. Would be interesting if this could be engineered to just take out something like the 100 micro-cells (at 4 lbs each), and toss em in a shopping cart. Maybe have a robot then sort and charge them in a special room full of charging racks. (like automated library book retrieval). But they would need to be built up in a certain way, and put in a housing, etc to go back in the car OK.

[salimmadjd]

swappable battery is important for those who need to drive beyond the battery range or don't have a good option to easily charge their cars overnight. This could be for people who live in big cities like San Francisco (although you can imaging a plug every parking spot 20 years from now) or for people who maybe going on a road trip. Which would make you wonder if people would not have two cars. One for daily commute the other for extended activity that might be fueled by some form of biodiesel. Hydrogen might also be another good solution at some point. This is something I proposed a long ago as part of my high school science fair. Basically using electricity for electrolysis of water to get hydrogen. You can the use the hydrogen as fuel cell or in combustion form for these long-range road trips instead of swapping batteries.

[jacques_chester]

The engineering practicalities around the storage and transmission of hydrogen mean that it's a bust.

You weren't the first to think it. When I was a kid in the 90s I read books, written in the 70s, about "the hydrogen economy" that would be everywhere by ... the 90s.