A new hybrid battery cost is dropping with every passing year. For my Prius, i think that the cost of a NEW battery is around $2000-2500 at most. You can also buy a USED one for a lot cheaper. And not sure about other hybrids, but resale value is one of the strong points of a Prius.
Link:
The 200,000-mile question: How does the Toyota Prius hold up?
"....Based on data from over 36,000 Toyota Prius hybrids in our annual survey, we find that the Prius has
outstanding reliability and low ownership costs. But we wanted to know if the effectiveness of the battery degraded over the long run. So we hooked up a 2002 Toyota Prius with
nearly 208,000 miles on the clock to our testing instruments and compared the results to the nearly identical 2001 Prius we tested 10 years ago.
Conclusion:
We found very little difference in performance when we tested fuel economy and acceleration.
Our testers were also amazed how much the car drove like the new one we tested 10 years ago. It certainly didn’t seem like a car that had traveled nearly the distance to the Moon. We were also surprised to learn that
the engine, transmission, and even shocks were all original.
If the battery ever did need to be replaced, it would run between $2,200 and $2,600 from a Toyota dealer, but it’s doubtful that anyone would purchase a new battery for such an old car. Most will probably choose to buy a low-mileage unit from a salvage yard, just as they would with an engine or transmission. We found many units available for around $500.
So is an old Prius a still a good value? We think so."
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So, after 10 years and 208,000 miles, the original battery is still in near perfect condition. This is why there are plenty of stories of cabbies running well over 300k miles on the original battery and still going!
Durability AND reliability AND low maintenance costs...and efficiency.