Depends on how you're slicing it. By the total flux of energy batteries may be able to handle 80% of the "energy traffic" over the course of a day by smoothing

Depends on how you're slicing it. By the total flux of energy batteries may be able to handle 80% of the "energy traffic" over the course of a day by smoothing out day/night cycles. However that last 25% needs to be stored over long periods where the cost is prohibitive to store in current battery systems.