So when the power goes out you unplug your fridge from the wall and plug it into the battery. In essence it operates like the standard camping battery/"solar generator", a la Jackery et al.
Having to plug in individual appliances seems to defeat the entire purpose. What happens if you’re away on holiday? Come home to a fridge full of trash? If power is back, do you even know how long the outage lasted? What about other devices that generally should have nonstop power or are typically hardwired? Sump pumps, HVAC equipment, water heaters, etc.