I'd like to see that flight test plan. IMO, a flight test isn't the right way to verify proper operation of the charger/battery/load system. One flight, or a couple of flights won't prove anything. The 787 flew how many hundreds (thousands?) of cycles without a failure. The same will happen here.
I'd say the test flights will be to prove a theory or demonstrate a reproducible error/issue.
Simply replacing a part and flying it to prove the issue doesn't re-occur won't be very convincing unless they intend to test fly for 50k hours...