[flappyeagle]

The station could test the battery and charge you/give you a credit depending on the capacity difference. Every battery would have an audit trail as well

[dale_glass]

A Tesla battery seems to cost around $20K per Google. So if your is at 50% life, do you get a bill for $10K?

That doesn't sound like a thing a lot of people would want.

[flappyeagle]

Yes you're right. So maybe the policy would not be exactly as you outlined.