The problem with your reasoning is that no cost-optimal plan of providing the society with energy would call for a week's worth of batteries. Furthermore, another problem is that judging from the number, you're presumably calculating with annual primary energy spent per capita, which will not be the same number after electrification (electrification is expected to massively slash primary energy expended -- for example in cars, where ~20 kWh of electricity replace ~6 liters of gasoline, primary energy shrinks roughly by a factor of three). Therefore translating current primary energy consumption into electricity that will need to be stored in an electrified future is nonsensical.