I know it’s not exactly the
I know it’s not exactly the same thing as a Toyota Prius, but I work on hybrid mass transit buses. The entire system is literally like a giant Toyota Prius. The transmission is just a scaled up Prius transmission that happens to have an extra reduction gear for operation below 15 mph. Otherwise it is identical to a Prius system just scaled up. It also operates at about triple the voltage because it is about 600 V. However it uses the same 7.2 V 6.5 amp hour battery cells that you would find in a Prius. It has been our experience that the vast majority of cells stay in excellent operating condition. Typically it is cells toward the middle of the pack that fail because they run hotter. Usually just replacing those cells results on a battery that will operate trouble free for years afterwards. I currently own a 2008 Toyota Highlander hybrid because with five kids I need a seven passenger car, and it currently has 217,000 miles on the original battery. If the battery ever failed I would want to replace just the cells that need replacing because a replacement remanufactured battery would exceed the bluebook value of the vehicle. Not only that but a vast majority of the cells would likely be perfectly good. Due to the way battery life is managed by the vehicles operating system, when it is at a “full charge” the batteries are actually only at 80% of the actual charge capacity. When the battery is “fully discharged” it is still at 20% of the actual charge capacity. This strategy drastically reduces the strain on the battery cells and allows them to last a very long time. The battery calls that don’t run hot tend to last an extremely long time. Many of our older hybrid buses are over 15 years old with over 1 million stop and go city miles on them, and about 85% of the cells are original.