A group of Tesla drivers, mainly from the United States, collected data on miles traveled and battery loss on their cars in a database. Almost 600 vehicles were involved for this, all Model S. The total mileage of all tested cars was more than 23 million miles (38 million kilometers). The conclusion was very impressive, after seven years the average battery capacity is still about 93 percent.
The average Tesla driver drove nearly 16,000 miles per year. Most buyers opted for the 85 kWh battery option, only one in six uses the 60 kWh option.
Battery capacity is measured by fully charging and reading the “nominal range” from the car, which is the estimated range if the car was moving under the same conditions and parameters that were used for the official assessment of the range of the car. Cars in the U.S. and Canada are EPA rated. Other countries use the NEDC standard. The values in the table are in accordance with the EPA standard, and reports in kilometers are converted to miles.
Early EV batteries showed problems and had a short life. This has given them an undeserved bad reputation. But that was a different chemistry and Tesla's battery management systems are superb. A 7% decline over 7 years suggests a 25% decline over 25 years. This means that the car will wear out before the battery. It also means that the 15 year battery life I've assumed for my calculations on grid energy storage should prolly be more like 25 years, nearly halving the LCOE/LCOS for this kind of battery. And since the up-front cost of batteries is falling by 20% a year, storage is going to be really cheap.
No comments:
Post a Comment