A few dozen kg is quite generous. There's 160 g of lithium in a kWh of lithium batteries. A typical household uses less than 30kWh per day. At 2.6 people

A few dozen kg is quite generous. There's 160 g of lithium in a kWh of lithium batteries. A typical household uses less than 30kWh per day. At 2.6 people per household, let's round to 10 kWh per person per day. So 1.6kg of lithium per day, 11kg for a week. But you don't need that much battery -- solar produces power even on cloudy days.