Traction battery remaining difference between Toyota app and MID

The percentage shown in the MID display is your available EV only percentage before it switches to HV mode, whereas the the percentage shown in the app is the total percentage charge remaining in the traction battery.

 

Software is hard... Toyota is better at building cars than building software... Some people have returned their Gen5 because of all the software bugs. Hopefully if you're patient these problems with get fixed via updates.

 

I put in some time trying to figure out what's going on with battery percentages and actual kWh used, even got Dr. Prius app with the OBD device to get some real numbers, so here it goes.

MID obviously goes from ---% to 100%, App goes from 30% to 100%. Actual 13.6kWh battery capacity and where we are at with these numbers is a little different.

Dr. Prius usually shows around 14% when MID is at 0% / app at 30%, but when full Dr. Prius shows 91%. Mathwise it all adds up. Toyota reserves top 9% of the 13.6kWh for longevity reasons (and probably to be able to use traction battery for braking when at full charge), and about 14% on the bottom for hybrid operations. So we have about 10.5kWh available for charging / EV only use. Give or take 10% of MID per kWh.

App is only useful for checking if the car has finished charging, honestly. I hope they update / fix it to at least match the MID, so I encourage everyone to write a review on the App Store.

Another noteworthy thing - kWh charged reported by the app are way off. Best theory I heard is it assumes old Prime's battery size. So if you see 7kWh charged in the app (usual for 0-100%), it actually means 10.5kWh, but that's not what your power company will bill you for. On a 110V outlet you'll burn 13.5kWh for a full charge. L1 has 25%+ overhead for heat / etc.