I understand that the expected behavior of a purchaser is to replace the battery with something bigger and better 5 or so years down the line. By then, we all hope that there will be cheaper, higher density batteries. Makes sense. I'll probably be one of them.
However, there are some (hopefully unlikely) scenarios where we might be stuck with a battery indefinitely:
- Purchaser falls on hard times, and wants to use the existing battery until it's well and truly dead. If you're only using a model S for small local trips, then perhaps 20% battery is just fine.
- Tesla goes out of business.
- Zombie Armageddon. Society breaks down, brains get eaten, and the only way we can get around is by charging our S's off solar panels.
- Etc.
My questions are these:
1. What is the best guess as to what happens to an S battery in the very long term? How do you think it will perform after 10 years? 15 years? 20 years? Does the battery max charge decline linearly? Exponentially? Does it actually reach a steady state at some point where the maximum range STOPS dropping? In 20 years, does it still have 25% charge? Or does it reach a point before then where it simply up and dies?
2. Over time, does the cost per mile increase because of charging inefficiencies? Let's say the battery in 10 years is at 50% of its 2012 max charge. Is the cost to charge it to its max 50% of what it costs to charge it today, assuming prices are the same? Or, does the battery charge less efficiently over time, requiring more current to charge the same amount?
Lots of hypotheticals here, but I find the exercise interesting to think about...
However, there are some (hopefully unlikely) scenarios where we might be stuck with a battery indefinitely:
- Purchaser falls on hard times, and wants to use the existing battery until it's well and truly dead. If you're only using a model S for small local trips, then perhaps 20% battery is just fine.
- Tesla goes out of business.
- Zombie Armageddon. Society breaks down, brains get eaten, and the only way we can get around is by charging our S's off solar panels.
- Etc.
My questions are these:
1. What is the best guess as to what happens to an S battery in the very long term? How do you think it will perform after 10 years? 15 years? 20 years? Does the battery max charge decline linearly? Exponentially? Does it actually reach a steady state at some point where the maximum range STOPS dropping? In 20 years, does it still have 25% charge? Or does it reach a point before then where it simply up and dies?
2. Over time, does the cost per mile increase because of charging inefficiencies? Let's say the battery in 10 years is at 50% of its 2012 max charge. Is the cost to charge it to its max 50% of what it costs to charge it today, assuming prices are the same? Or, does the battery charge less efficiently over time, requiring more current to charge the same amount?
Lots of hypotheticals here, but I find the exercise interesting to think about...