Agreed the replacement rates have been lower than anticipated. The only problems have been the predictable ones - bad designs like the early Nissan Leafs which

Agreed the replacement rates have been lower than anticipated. The only problems have been the predictable ones - bad designs like the early Nissan Leafs which had no thermal management. That said, the amount of datapoints here should increase by orders of magnitude over the next 2-3 years as the first million Model 3s roll out of their 8 year battery warranty period. I'm sure that once there is regular demand for battery replacements, the cost won't be much different than an engine rebuild. So even the pessimist case for EVs today is "well the TCO is lower for the first decade but then..." and I think we will be solving the "but then.." soon.