Ok, another question:
You think it would be acceptable to have a car that can only drive 100 miles? Why would you want more?
I can charge my phone in under an hour. I can do so in the car, at my desk, or any of hundreds of other places given the ubiquity of micro-usb. For me, once I can go all day on a charge any excess capacity just means more weight/bulk.
A week-long battery would be obscenely large, the phone unnecessarily heavy all while providing nearly zero benefit to my use case.
Now: god forbid if i forget my charger when on business trips!
Battery tech is constantly advencing too, but instead of using that extra power for longer battery life they put in more useless stuff. Who needs a fing barometer in his mobile!?