Some homes can benefit from storing electricity and configured correctly the National Grid can benefit as well as the homeowner.
Solar panels on a home will typically produce maximum power between March and October and during daylight hours. however if the residents go out to work or school during weekdays this electricity will offer no benefit to them unless it is stored and used at peak times between 4pm and 10pm (weekdays). Battery storage alongside Solar PV makes a lot of sense. It can reduce use of grid power from houses by a lot with consequent economic benefits. If an electric vehicle is charged overnight, then this could be charged from stored electric power offering power for zero cost.
Some Electric grid companies will also use home battery arrays as a source of electricity for balancing the grid, and may even pay the owner of the array for the electricity used.