[Bug]: Default SPMe and DFN models/examples have no NE potential or overpotential

[tommaull]

PyBaMM Version

lastest Dev and Main as of 27/11/23

Python Version

3.9

Describe the bug

NE response is implausible - hovering around 0 potential, with no overpotential behaviours.

Steps to Reproduce

Run 23.9 Main, SPMe example. Observe NE behaviour.

Relevant log output

No response

[rtimms]

This is because we measure potential wrt the solid phase negative electrode potential at x=0, whereas I'm guessing what you're expecting is the potential measured wrt to a different reference, such as the electrolyte potential?

[rtimms]

See also #3470 and #3254