DarkStar said:
The difference in the Leaf is that the coolant isn't under pressure like a traditional engine radiator system, thus it is very unlikely to develop a leak. Sure, you'll have to glance it, but it shouldn't need anything more than annual maintenance.
You probably don't need to do more than check the fluid levels more than a couple times a year.
Coolant these days typically lasts at least 3-years 36k miles before a change - and usually a lot longer. For example, on the Prius, you only need to change the engine and inverter coolant after 10 years / 100,000 miles and every 5 years / 50,000 miles after the first one.