Here's how I answered in another venue:
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You've heard EV's are very cheap to operate. True. And that they are expensive. Also true. If lowest total cost of ownership is your goal, nothing can beat a good used car with conventional engine, reasonably small, reasonably high gas mileage, and reasonably good repair history. Nothing that is except a bicycle and/or a transit pass.
So if you're looking then probably lowest TCO isn't your top goal. Maybe you're concerned for the world's climate, for your city's air quality, for the economic and/or military security of reducing foreign oil imports, for your ability to get around in the event of oil supply disruptions, or you like being among the first to try out the New Thing.
First step, characterize your driving pattern in terms of both average daily distance and variability. You can use this to estimate how various cars would work for you. Most Americans greatly overestimate how many miles they drive (probably because we sit so long in our cars while stopped in traffic). If you drive less than 60 miles a day (22,000 miles per year) with very little day to day variation then a Leaf could work well for you. If you drive less than 40 miles a day (15,000 miles per year - still higher than the average American) then a Volt could run almost entirely on electricity.
You may have read Nissan's advertising that the Leaf's range is 100 miles. Yes there are test cycles for which it goes 100 miles or farther. I could probably drive mine over 100 miles - around in circles in my neighborhood at 30 MPH. But the fact is if I'm going 100 miles then I'm driving on the freeway where the slow lane goes at the speed limit of 65 MPH and the other lanes go faster. For combined city/highway driving the EPA's estimate of 73 miles is pretty close.
Variability is as important as distance. Even with an average of only 15 miles a day, if you fairly often have 80 mile days then a Leaf might not work well for you while a Volt would. If you have a second (gasoline) car in the family and could easily switch cars on your high mileage days then a Leaf could still be a good fit. If either would serve equally well, a Leaf will have somewhat lower operating cost, lower purchase cost, less mechanical complexity, and greater passenger carrying capacity.
Then there are the really long days, such as road trips. With quick charging stations just beginning to be deployed a Leaf can practically make regional trips of maybe 200 miles round trip, whereas a Volt can make road trips of any distance. As can that second gasoline car in the family. A Ford Focus Electric or Toyota RAV4 that lacks quick charge capability is purely a city car.
While a Volt starts off the day as an EV it may end the day as a gasoline car with 40 MPG. Not bad, but if you have a lot of long distance driving you may prefer a 50 MPG Prius. It has a very short electric range and the gas engine kicks in anyway at modest speeds. I think of Volt as a gas assisted electric, and Prius as an electric assisted gas car, where plugging in just raises your effective gas mileage from 50 to 75 or more.
Operating cost of a Leaf depends on your electric rate. On my special 7.6 cents/kWh EV overnight rate it works out to about 2 cents a mile. Your rates could be higher. Or if you're charging with excess solar production that the utility would otherwise pay you a pittance for, your effective rate could be much lower.
On top of that 2 cents I'm figuring on about an additional 4 cents a mile for eventual replacement of the battery pack. This, the biggest portion of my operating cost, is also the biggest unknown. Nissan refuses to disclose the replacement price of a battery pack (swap). Probably they won't say because it's outrageous today, and they're counting on the new Tennessee factory and economies of scale to drive the price down dramatically by the time anyone needs a replacement.
Battery lifetime is another unknown, but it will probably degrade to something like 80% of original capacity in 5 years. That takes your original 74 mile range down to about 60 miles. If that still meets your needs then you don't need a battery replacement yet. If your range was marginal to begin with you could face battery replacement even sooner. The battery degrades most quickly when it's new and tapers off. So someone driving 40 miles a day in a 5 year old car with an 80% battery might yet get another 5 years of use out of it. Deployment of public quick charging infrastructure is another unknown, and clearly if you can recharge quickly and easily wherever you go then you will care less about lost battery capacity. The final uncertainty is improved technology. I'm guessing that by the time I have to replace my battery the new one will be cheaper, lighter, and have higher capacity. But no guarantees.
Finally there's the driving experience. It will probably be the smoothest and quietest car you've ever driven, and may well be the quickest off the line unless you've been driving a Porsche. After you get used to driving electric it's hard to go back to driving an old fashioned gas burner with its rough balky gas pedal.