Don't believe anything you see in the Internet. This is not correct. The exact BEV allocation at the is 6.34 kWh at the 240-V plug. This is stated by the EPA and has been verified by ChargePoint EVSEs. The exact BEV allocation at the battery output terminals is harder to figure out, but I get roughly 38 miles at 6.3 mi/kWh on MFD. This is 6.0 kWh at the battery, which is quite higher than the 5.3 kWh estimated by the Internet bloggers. It corresponds to a 95% charging efficiency, which is pretty good, same as Tesla's charging efficiency.
5.3 kWh should be 6.0 kWh. The HEV reserve is about right, but perhaps it is slightly higher 1.1 kWh. Therefore, the top buffer is probably overestimated. The bottom buffer could be slightly lower, too. I estimated the Level 2 (240-V) charging efficiency to be 95%. Level 1 (120-V) charging efficiency should be around 87–90%, varying with conditions. 8.8 kWh is 8.79 kWh to be exact. Note that the battery capacity also somewhat varies with the discharge rate (C-rate).
You bring up good points, thanks. I base my top and bottom buffers on myriad videos that john1701 has posted. I'll stand by my creation, albeit not perfect. You're welcome to create your own
Yep, I'm a visual learner. Just couldn't grapple how the Prius Prime 8.8 kWh pack allocated top and bottom buffer, EV and HV. My graphic helped me better understand.
Battery capacity also drops with mileage. So, if someone sees a drop from 6.0 kWh in a fresh battery to 5.3 kWh in a high-mileage battery, which is 12%, it is not unusual.
I have 213,000 miles on my 2019 Prime. The last few months I've noticed that sometimes the indicator shows the battery has fallen below the HV charge line. When this happens the car drives jerky and poor throttle response for a few minutes until it gets charged up to the HV line. I can only charge up to 18 miles now and only get about 14 miles of that. I have charged it everyday, sometimes 2 or 3 times. I use 220v to charge it and it only takes a couple of hours. Incedently, the 110v charging cable that comes with the car can be easily converted to 200v by making a dog bone with 110v going to each leg of the 110v plug. Anyway, it looks like its time to replace the battery.
Yup, looks like you've exhausted the life of the battery. 213K miles is pretty good, I'd say. 2 to 3 charges a day since 2019 is a lot of cycles. Good luck.
