We can roughly estimate lithium ion batteries as 500 watt-hours per liter. Which makes a million watt-hours 2000 liters, which is two cubic meters. Add in ext

We can roughly estimate lithium ion batteries as 500 watt-hours per liter. Which makes a million watt-hours 2000 liters, which is two cubic meters. Add in extra overhead and it's still not all that much.