For instance, the battery in a Tesla Roadster only drops to 80 – 85% after 100,000 miles of driving. Tesla, on the other hand, had originally estimated that the battery will drop down to 70% after 5 years or 50,000 miles – reality beats theory.
The survey also noted that cold or hot climate didn’t count to this equation, nor did the driving style (granny-like or sporty).
The graph below should be edifying:
Now the figures above have been collected from Tesla customers, and Teslas are known for having high-quality batteries and drivetrain systems, so it’s no wonder they got better numbers.
To be more on the accurate side, the survey should’ve asked customers of different EV manufacturers such as GM or Nissan. However, this survey alone proves lithium ion batteries can be used successfully in electric cars and that electric cars are a good alternative to gas-powered cars when it comes to reliability – even of the batteries.
Here’s the report (pdf).
pictures (c) Plug In America