One of the biggest worries about electric cars--and hybrids for that matter--is whether their expensive high-voltage battery packs will last the life of the car.

If not, potential buyers worry, they may be saddled with thousands of dollars of cost in years to come.

The evidence on hybrids is largely positive over the last 15 years, but there's less evidence for electric cars.

DON'T MISS: Chevrolet Volt: Green Car Reports' Best Car To Buy 2016

Now, however, we have a new data point: Erick Belmer's 2012 Chevrolet Volt range-extended electric car just crossed 300,000 miles last week, as he posted to a Volt Owner's Group on Facebook.

And Belmer says it shows no apparent degradation in either its battery capacity or its electric range (rated at 35 miles for that model year).

After 140 comments and almost 800 Likes, the general consensus among owners is that the Volt appears to be hugely durable, and that battery life is the least of a Volt driver's worries.

2012 Chevrolet Volt

2012 Chevrolet Volt

(Keeping the car in electric mode as often as possible is top of mind for many owners, who recharge their Volts an average of 1.4 times a day, according to GM data.)

Belmer calls his Volt "Ol' Sparkie," and he's managed to do more than one-third of the total miles on grid power: 103,000 of those 300,000. 

Those driven on gasoline came in close to the Volt's combined 37-mpg EPA rating, cutting fuel costs substantially.

ALSO SEE: Should I Buy A Used Chevy Volt Electric Car?

He drives about 6,500 miles per month to commute from Bellville, Ohio, to his job as a millwright in GM's assembly plant in Lordstown, Ohio.

Rather than moving when the local GM factory closed, Belmer remained in Bellville for family reasons.

After calculating how to minimize total commute costs over what would clearly be high miles, the 2012 Volt came out ahead, even given its price of $40,000 (likely reduced by a GM employee discount).

2012 Chevrolet Volt

2012 Chevrolet Volt

Still, while 300,000 miles on a four-year-old Volt is impressive, it's nowhere near the highest mileages logged by older hybrid cars.

Take, for instance, the 2004 Toyota Prius taxi in Vancouver that was retired seven years later with an odometer reading of a little more than 1.5 million kilometers (932,000 miles).

Looks like Belmer has a ways to go yet, eh?


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