Sun has a peak of energy during the day that usually cannot be paralleled with the time in which the home uses more electricity. The necessity of a storage system for later use is a very complex field that is going to experience multiple advances in the next decades. Some players are providing options based on Li-ion, deep cycle, flooded types, gel or absorbed glass mat batteries, and others.
As the price per watt continues going down, and the savings in the long term are thousands and thousands, multiple homes install photovoltaic panels, and the backup system would be a very demanded extra for the setup. Who has the most interesting technology and price for sure will increase the revenue until satisfactory degrees.
These battery systems usually account use for not so much time, but what happens to those battery projects that account with winter as the season in which the home needs more energy? Today there are technologies that almost don't lose capacity over the months, up to 90% of standing charge after a year or even better. There's what it looks a great fight to overcome limitations in energy density, self discharging rate, ease of production, and therefore low price. Research and development in this area really could ensure an enormous revolution to multiple sectors, and providing a path to a clean and sustainable society in not so many years. Sadly some governments and institutions seem to not understand it well as they don't invest, or create research groups of international experts.
And there's also the possibility of converting the electricity into other kind of energy. Hydrocarbons for instance, use chemical bonds to provide energy, and if Nature does it, you could bet is a solution.