If you plug the app's device into a computer, the logs can be found by following the "map" here:
Average Battery Cell Voltage: 798 mV
The higher mV numbers might be historical, so it would be good if we could confirm the current
Max/Min Status, from the logs, or in a shot like this one I took at 0.00% when the car wouldn't close the contactors with the left door or the key, only by plugging in:
I there's no digit missing, & there really is a cell at 0798 mV that's WAY too low for the car to allow charging, meaning you'd have to charge the cells individually, after dismantling it as shown below by @vladifresh
& then using the method described here by @ATSAaron
The easy DIY tips (click here) won't fix absolutely everything, so if they fail, here's some advanced DIY which could also be done by a shop (see post #2 below): Click here for the technicians' training guide. A used PIM works! (Power Inverter Module). It's even plug-&-play! HUGE thanks...