A home battery can shift spare solar electricity into the evening, but its value depends on how much energy would otherwise be exported and when the household uses power.
Compare generation with evening demand
Homes that export regularly during the day and use more electricity after sunset may make better use of stored energy. A review of interval data can show how often that pattern occurs.
Size for useful cycles
A larger battery is not automatically a better investment. The useful capacity should match realistic surplus generation and demand so the battery can charge and discharge regularly.