Battery degradation is one of the biggest concerns for electric vehicle owners and potential buyers, but the data on Tesla battery packs has been very reassuring thus far.
Now the latest data shows less than 10% power capacity degradation after more than 160,000 miles on Tesla battery packs.
A group of Tesla owners in the Netherlands and Belgium Tesla forum is collecting data from more than 350 Tesla vehicles around the world and updating it frequently in a public Google archive.
We have reported the data before, but since then they have added many more vehicles and those vehicles have driven much more, completing more battery cycles.
The data clearly shows that for the first 50,000 miles (100,000 km), most Tesla battery packs will lose about 5% of their capacity, but after the 50,000 mile mark, the capacity stabilizes and it looks like it could. be difficult to make a package degrades by another 5%.
The trend line currently suggests that the average battery pack could travel more than 300,000 km (186,000) before approaching 90% of its capacity.
These are the relevant graphs of the data collection effort (full frame on the left and zoomed to 80% on the right):
There are some outlier battery packs and they tried to figure out why by collecting other data such as DC fast charge frequency and daily charge status, but there is no clear indication that any of those factors have a significant impact based on their data .
That said, Jeff Dahn, a renowned battery researcher and leader of Tesla's research association through his battery research group at Dalhousie University, said that he recommends charging just 70% daily to extend the life of the battery. drums.
Tesla cautions that it does not cover battery degradation from "battery use" under its Model S and Model X warranty to a specific level:
“The battery, like all lithium-ion batteries, will experience a gradual loss of energy or power with time and use. Loss of power or battery power over time or due to or as a result of battery use is not covered by this limited battery warranty. Consult your owner's documentation for important information on how to maximize battery life and capacity. "
But for the Model 3, Tesla introduced a warranty with a new 70% battery capacity retention guarantee.
The Model 3 is equipped with different battery cells and a new battery pack architecture, but if the Model S data is any indication, it shouldn't be a problem.
Battery degradation is often a big concern for new electric vehicle buyers. To some extent, the Nissan Leaf could be the culprit as it had a lot of issues about it, which is why Nissan now has a much more comprehensive battery capacity warranty.
A recent study shows that with the original 24 kWh pack it loses approximately 20% of its capacity in 5 years and the newer 30 kWh battery pack from Nissan loses capacity more quickly than the previous pack:
However, Tesla vehicles have a much more advanced battery thermal management system than Leaf's, and the data from early Model S vehicles has been really encouraging, as we can see above.
As for anecdotal data, my own Model S, which is one of the first 2,000 vehicles ever made, only lost about 6% of its capacity in 5 years.
CEO Elon Musk has been touting even more potential for the Tesla battery pack by once referring to the battery pack Tesla was testing in the lab. He said the company had simulated more than 500,000 miles on it repeatedly cycling and that it was still operating at more than 80% of its original capacity. At that point, the car is more likely to outperform the battery at this type of mileage.
Original article (in English)