Tesla batteries weigh over 1000 lbs. They're about a third of the total weight of the car, and they are embedded throughout the chassis. What if we just swappe

Tesla batteries weigh over 1000 lbs. They're about a third of the total weight of the car, and they are embedded throughout the chassis. What if we just swapped a part of it? The 85 kWh battery pack of the Model S, which weighs 1,200 lb, gets you about 400 miles. If you decided to make a part of it swappable, what size would be appropriate, and where would it fit? If we assumed there were a 50 pound battery you could just pop in and out (that would be pretty difficult to handle, but let's assume), that would only get you another 16 miles. Good for an emergency, yes, but not a replacement for a charging station, and that's a pretty big architectural shift, and requires battery stations everywhere, all for just another 16 miles.