This isn’t really consistent with what else BMW are stating – that they will be recycling old battery packs into stationary storage applications. My take is that it will be a long time till anyone finds out. With an 8 year 100,000 mile warranty I’d wait at least 8 years to replace them unless I hit 100,000 miles early. Though a few people might hit that in the next couple of years! Given 30k+ miles some people are reporting.
I tend to keep cars unless I really have a change of needs or something (like an i3) tempts me. My previous car (which is still have) is an 04 X-Trail – so now 11 years old. Assume I replace the battery just after warranty has expired. On current 7% cost decline and 8% density increase in 2023 I’ll be able to get a new pack at just over ½ the current price, with a weight of only 118kg instead of 230kg.
That said - I think whatever you read about being “difficult to replace” is maybe referring to “upgrading” the cells not replacing them. I.e. you can swap out the cells for OEMs replacements and the battery management system will know how to deal with them. But stick some new chemistry in there and it will need to be re-programmed with some new max safe temp, SOC max, SOC Min, Max C charge, Max C discharge, Vmax, Vmin, parameters and how to balance the cells in its maintenance cycles. Nothing a third party EV specialist couldn’t deal with – assuming the BMS is flashable and/or the charge controllers can deal with the battery volatage/current requirements or request the right numbers from an external DC Rapid chargers. In my mind – having ½ the weight ½ the original price, or double the capacity at same as the original price gives some interesting parameters to work with. A 50kWh battery would mean using the REX about twice a year. That’s if previous trajectories remain constant. What if a new cell comes along that can take 100C charge rates (there’s been some demos). Effectively 5 minutes charge, then you are stuck with a CCS unit that’s only able to handle 50kW so you might want to upgrade that – if there’s been a rollout of 1Megawatt capable CCS units!! LOL. Currently there’s too many variables to predict 3 years out let alone 8.
As it’s such a long time away will just have to wait to see what options there are in a few years. Worst case should be a BMW OEM job for circa 10,000 dollar/pound/euros and anything down to half that if costs drop or less for 3rd party stuff with a company who knows what they are doing. At the moment I can list on one hand the number of companies I’d trust to do that in the UK! Maybe in 2023 I might have a choice of 3 local suppliers – but I doubt it.
