Manufacturers warranties are now for 12 year, so it is reasonable to expect that e-Bus batteries will last about 12 years before loss of capacity will impact the operation of the bus.
Batteries removed from e-buses still have many years of useful life in grid storage, an essential part of the charging system for the buses. After a further 10-15 years, batteries will be recycled.
Diesel buses require engine and transmission replacements during their operational life, replacement of batteries in e-buses is a simpler process.