....I have been told that the replacement battery costs on a Nissan Leaf is over £15k,perhaps someone can verify that?....
Yes that is the position Dave, the cost is roughly half the gross cost of the Nissan Leaf car, £31,000. It was this issue that killed the early Peugeot 207 e-car many years ago, £4000 to replace it's NiMh battery, said to be at 4 years intervals but proving to be much shorter. The Nissan Leaf battery was originally claimed to be good for 10 years, but they now say 7 years. In fact the warranty is 4 years.
Nissan are of course a wholly owned Renault company, and Renault also market e-vehicles, a range of three cars and a van. Their version of the hatchback Leaf has a saloon body and is called the Fluence. Interestingly Renault don't sell with battery, the Fluence is £22850 for example and the battery costs £86 per month over a one year agreement covering 6000 miles, or £70 a month over 5 years. For higher mileage drivers, there's an £81 per month agreement for five years at 9000 miles per annum. Any annual excess on these is at 4p per mile.
These seem to indicate the battery is only safe for 5 years, just a bit longer than the warranty period.
The competition is mainly from the Mitsubishi electric i-car, also sold as a Peugeot and a Citroen. They also lease the batteries, for a maximum of 4 years, another life indication.
N.B. There is a government subsidy on the original purchase of an e-car of £5000. That doesn't apply to Renault's smallest model, the circa £7000 Twizy which is not classed as a car but as a heavy quadricycle.
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