Merge a7043df into 2c223ba

Author: brosaplanella

CHANGELOG.md

@@ -31,6 +31,7 @@
 
 ## Bug fixes
 
+-   Fixed a sign error in the positive electrode ohmic losses ([#1407](https://github.com/pybamm-team/PyBaMM/pull/1407))
 -   Simulations now stop when an experiment becomes infeasible ([#1395](https://github.com/pybamm-team/PyBaMM/pull/1395))
 -   Added a check for domains in `Concatenation` ([#1368](https://github.com/pybamm-team/PyBaMM/pull/1368))
 -   Differentiation now works even when the differentiation variable is a constant ([#1294](https://github.com/pybamm-team/PyBaMM/pull/1294))

pybamm/models/submodels/electrode/base_electrode.py

@@ -53,7 +53,7 @@ def _get_standard_potential_variables(self, phi_s):
             phi_s_av_dim = param.U_p_ref - param.U_n_ref + pot * phi_s_av
 
             v = pybamm.boundary_value(phi_s, "right")
-            delta_phi_s = phi_s - v
+            delta_phi_s = v - phi_s
         delta_phi_s_av = pybamm.x_average(delta_phi_s)
         delta_phi_s_dim = delta_phi_s * pot
         delta_phi_s_av_dim = delta_phi_s_av * pot