Where the heck did you get that idea from? The batteries discussed in this article are storage stations that are part of the grid, not something bought and maintained by the consumer.
In the UK, you could sell all your unused excess roof solar energy back to the grid. But this is at a wildly reduced rate - fractions of the cost you would pay for electricity. So you would then need batteries to store the energy... But then you incur the drawbacks of these (high maintaince costs).
With all these personal solar solutions, with batteries, panels etc being bought and provided by the consumer, it seems an obvious point to me that quite a lot of electric infrastructure is moving to the private domain, with discounted electricity then being sold back to the public utilities.