Not my car, and not my dime
First, as someone noted, the battery packs will vary in quality. We'll be paying upwards of $15K for our battery pack in a new car, I'm not letting you swap it for a 4 year old pack built using cheap components and lesser grade batteries. F* no!
Next, forget the cost of the robot, the packs are $15K each... You'll need hundreds to get through a day. Most of these packs would also be swapped at freeway stations, long distance filling spots, and they could need hundreds or thousands of them to make it thorugh a day.
third: it's not just storage of the packs, they'll need to be shuffled back and forth between stations, DAILY. They weigh hundreds of ounds. This will require additional motor assits or robots, lots of trucks, and men to do the work on the cheap...
Fourth: charging. Swap the pack, you still need to recharge it. This means not only storage, but cabled storage, and large scale smart charging systems that make sure batteries are not only in stock, but to know which one is ready to go in the next car... If you need the charging stations anyway, just build charging stalls for people to park in and charge...
Fifth: it's mostly irrlelvent! By the time we get 200 of these stations built we'll be shipping cars using Li-Ti batteries that charge to 85% in 5 minutes or less. It takes me 3-6 minutes to fill the gas tank in my Van today (depending on the pump speed), 5 minutes to go 200+ miles is not an issue. Besides, i'll have gas backup to extend that range to more like 400 miles, and I (or someone lese in the car) do need to pee every 3-4 hours anyway... On long trips, those pit stops are never less than 10-15 minutes for us.
Sixth: Inventory. We're hard up enough producing enough battery packs to put in the carrs rolling off the lot. You'll need to multiple that number by 5 to keep up with demand for packs to be stored at stations.
7th: Manufacturers: not only will it be IMPOSSIBLE (let alone cooperativley, but also from a simple design perspective) to put the same battery in every car, let alone the same battery capacity in every car. Even using modular packs with smaller cars having 1 or 2 and larger cards having 4 or 6, you're still talking about structural limitations on where a battery can fit ubder a car (and most are not UNDER cars, but under seats, in trunks, packed in around the front hood, etc). There's NO WAY to make this a universal system...
8th: Cost: Filling a battery costs electricity, a chaep meter, a cable, and a guy to watch. Replacing a battery STILL costs that, PLUS an expensive robot requiring maintenance, large numbers of replacable packs, guys to move them, places to store them, infrastructure to support them, this is simply assonine. Even if it would take 30 minutes to get a full charge, a 400 mile hybrid range is worth 15-20 extra minutes per stop if it costs 1/4th as much... Charging a battery costs about half what gasoline goes today to go the same distance. So, 400 miles should cost about $25 (including the gas to double the range). Swapping a battery (plus the gas to double the range) would cost not less than $80 by rough estimates, assuming a full 1000 charges per battery pack before it's thrown out. Between my home in the south and upstate NY, a trip i take frequently, I'd need to start full and fill up twice on the way. Replacing my battery packs would cost nearly $100 more and save me what, 40 minutes? IT'S NOT WORTH IT!
This is a crock plan cooked up by the NiCad folks, who's batteries take 3-8 hours to charge. The Li-Po and Li-Ti batteries charge in minutes, 30 tops. you charge to 85%, not 100%... You stop more often (1 extra stop every 1200 miles or so) but you save hours doing so.
No, you'll never see 10 minute charges at home. a 400Amp house circuit might get you a 2 hour charge, but a 4 phase high power line at a filling station can top off a 40KwH battery pack in 5 minutes... and it's safe. You'll need hydrolic assist to move the cable around (it;s about 6" in diameter, and uses interlocking flexi joints (it;s not a cable that bends on it;s own, it only bends at joints), but even a child could move the cab;e to the car with an assist system and plu it in to a resonably universally located port (where a gas insert is today, just in the front half of the car to maintain safe seperation from the existing fuel port, which hybrids will still have).