I was assuming the rental contracts would be long-term enough to guarantee pricing and availability for the life of the car, e.g. a 10 year fixed price contract with the option to renew at the same price for another 10 years.
It's a nascent industry at the moment - I'm not sure how it will play out. Presumably some day battery lives will be proven, manufacturer reputations will be established, and consumers and regulators will know what to look for, check and standardise. Once the technology risks and information asymmetries are reduced, passing the risks to manufacturers will be less appealing and we might all end up paying up front for our 30-year batteries.
