I haven't seen anyone discuss the following potential issues with electric cars: 1) How long do the batteries last? Five years? 10? 2) What does it cost to replace the batteries, including removal, disposal and installation? – David
The short answer is that nobody knows – yet. The failure rate has been less than one per cent and those were covered under warranty.
Generally speaking, the large nickel-metal-hydride batteries in hybrid vehicles are warranted for eight years and 160,000 km. Toyota says the nickel-metal hydride battery pack in the Prius is good for the life of the car or almost 300,000 km.
Toyota and Honda warrant the battery pack for eight years or 160,000 km. This is not much different than the situation with a conventional engine – they commonly last far past the warranty coverage.
Taxi fleets in various parts of the world are using hybrids, partially because of the lower operating costs in a city environment and partially because they get a slight price break from manufacturers anxious to find out "worse-case" scenarios with respect to maintenance, reliability and battery life.
Recently, the cab I hailed in Tokyo was a well-worn Prius with more than 310,000 km on it. While the car itself was pretty much crapped out, and there were some strange noises coming from the drive system, the driver said it still had the original battery.
Replacement costs? Again, there is insufficient data upon which to base an answer. In the early hybrid vehicle days, guesstimates ranged from $4,000 to $8,000 – but they were pure guesses because none had been replaced yet. More recent numbers lie in the $2,500 to $4,000 range, not that much higher than a brand new engine and transmission in a conventional car.
As is always the case, smaller will be cheaper. The pack in a Prius will cost less than that of a Highlander, for example. Disposal and subsequent environmental damage is another issue.
If the replacement is done at a dealership it will likely comply with local recycling laws. If done in a backyard or by a less-than-reputable shop or person, that would not be the case. Of course, this would be the same person or ship that would throw an old engine out back and let it leak oil, gas and other fluids into the ground.
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