Electrolyte overpotentials

pybamm/models/full_battery_models/base_battery_model.py

@@ -848,12 +848,10 @@ def set_voltage_variables(self):
 
         # Battery-wide variables
         V_dim = self.variables["Terminal voltage [V]"]
-        eta_e_av = self.variables.get("X-averaged electrolyte ohmic losses", 0)
-        eta_c_av = self.variables.get("X-averaged concentration overpotential", 0)
-        eta_e_av_dim = self.variables.get("X-averaged electrolyte ohmic losses [V]", 0)
-        eta_c_av_dim = self.variables.get(
-            "X-averaged concentration overpotential [V]", 0
-        )
+        eta_e_av = self.variables["X-averaged electrolyte ohmic losses"]
+        eta_c_av = self.variables["X-averaged concentration overpotential"]
+        eta_e_av_dim = self.variables["X-averaged electrolyte ohmic losses [V]"]
+        eta_c_av_dim = self.variables["X-averaged concentration overpotential [V]"]
         num_cells = pybamm.Parameter(
             "Number of cells connected in series to make a battery"
         )

pybamm/models/submodels/electrolyte_conductivity/base_electrolyte_conductivity.py

@@ -274,6 +274,7 @@ def _get_whole_cell_variables(self, variables):
             The variables including the whole-cell electrolyte potentials
             and currents.
         """
+        param = self.param
 
         phi_e_n = variables["Negative electrolyte potential"]
         phi_e_s = variables["Separator electrolyte potential"]
@@ -284,10 +285,52 @@ def _get_whole_cell_variables(self, variables):
         i_e_p = variables["Positive electrolyte current density"]
         i_e = pybamm.Concatenation(i_e_n, i_e_s, i_e_p)
 
+        c_e_n = variables["Negative electrolyte concentration"]
+        c_e_s = variables["Separator electrolyte concentration"]
+        c_e_p = variables["Positive electrolyte concentration"]
+
+        T_n = variables["Negative electrode temperature"]
+        T_s = variables["Separator temperature"]
+        T_p = variables["Positive electrode temperature"]
+
+        # concentration overpotential
+        indef_integral_n = pybamm.IndefiniteIntegral(
+            param.chi(c_e_n, T_n)
+            * (1 + param.Theta * T_n)
+            * pybamm.grad(c_e_n)
+            / c_e_n,
+            pybamm.standard_spatial_vars.x_n,
+        )
+        indef_integral_s = pybamm.IndefiniteIntegral(
+            param.chi(c_e_s, T_s)
+            * (1 + param.Theta * T_s)
+            * pybamm.grad(c_e_s)
+            / c_e_s,
+            pybamm.standard_spatial_vars.x_s,
+        )
+        indef_integral_p = pybamm.IndefiniteIntegral(
+            param.chi(c_e_p, T_p)
+            * (1 + param.Theta * T_p)
+            * pybamm.grad(c_e_p)
+            / c_e_p,
+            pybamm.standard_spatial_vars.x_p,
+        )
+
+        integral_n = indef_integral_n
+        integral_s = indef_integral_s + pybamm.boundary_value(integral_n, "right")
+        integral_p = indef_integral_p + pybamm.boundary_value(integral_s, "right")
+
+        eta_c_av = pybamm.x_average(integral_p) - pybamm.x_average(integral_n)
+
+        delta_phi_e_av = (
+            pybamm.x_average(phi_e_p) - pybamm.x_average(phi_e_n) - eta_c_av
+        )
+
         variables.update(
             self._get_standard_potential_variables(phi_e_n, phi_e_s, phi_e_p)
         )
         variables.update(self._get_standard_current_variables(i_e))
+        variables.update(self._get_split_overpotential(eta_c_av, delta_phi_e_av))
 
         return variables
 

pybamm/models/submodels/electrolyte_conductivity/full_conductivity.py

@@ -39,12 +39,50 @@ def get_coupled_variables(self, variables):
         c_e = variables["Electrolyte concentration"]
         phi_e = variables["Electrolyte potential"]
 
+        c_e_n, c_e_s, c_e_p = c_e.orphans
+        phi_e_n, _, phi_e_p = phi_e.orphans
+        T_n, T_s, T_p = T.orphans
+
         i_e = (param.kappa_e(c_e, T) * tor * param.gamma_e / param.C_e) * (
             param.chi(c_e, T) * (1 + param.Theta * T) * pybamm.grad(c_e) / c_e
             - pybamm.grad(phi_e)
         )
 
+        # concentration overpotential
+        indef_integral_n = pybamm.IndefiniteIntegral(
+            param.chi(c_e_n, T_n)
+            * (1 + param.Theta * T_n)
+            * pybamm.grad(c_e_n)
+            / c_e_n,
+            pybamm.standard_spatial_vars.x_n,
+        )
+        indef_integral_s = pybamm.IndefiniteIntegral(
+            param.chi(c_e_s, T_s)
+            * (1 + param.Theta * T_s)
+            * pybamm.grad(c_e_s)
+            / c_e_s,
+            pybamm.standard_spatial_vars.x_s,
+        )
+        indef_integral_p = pybamm.IndefiniteIntegral(
+            param.chi(c_e_p, T_p)
+            * (1 + param.Theta * T_p)
+            * pybamm.grad(c_e_p)
+            / c_e_p,
+            pybamm.standard_spatial_vars.x_p,
+        )
+
+        integral_n = indef_integral_n
+        integral_s = indef_integral_s + pybamm.boundary_value(integral_n, "right")
+        integral_p = indef_integral_p + pybamm.boundary_value(integral_s, "right")
+
+        eta_c_av = pybamm.x_average(integral_p) - pybamm.x_average(integral_n)
+
+        delta_phi_e_av = (
+            pybamm.x_average(phi_e_p) - pybamm.x_average(phi_e_n) - eta_c_av
+        )
+
         variables.update(self._get_standard_current_variables(i_e))
+        variables.update(self._get_split_overpotential(eta_c_av, delta_phi_e_av))
 
         return variables
 

tests/unit/test_models/test_submodels/test_electrolyte_conductivity/test_full_conductivity.py

@@ -12,13 +12,13 @@ def test_public_functions(self):
         param = pybamm.LithiumIonParameters()
         a = pybamm.Scalar(1)
         surf = "electrode surface area to volume ratio"
+        a_n = pybamm.FullBroadcast(a, "negative electrode", "current collector")
+        a_s = pybamm.FullBroadcast(a, "separator", "current collector")
+        a_p = pybamm.FullBroadcast(a, "positive electrode", "current collector")
+
         variables = {
             "Electrolyte tortuosity": a,
-            "Electrolyte concentration": pybamm.FullBroadcast(
-                a,
-                ["negative electrode", "separator", "positive electrode"],
-                "current collector",
-            ),
+            "Electrolyte concentration": pybamm.Concatenation(a_n, a_s, a_p),
             "Negative "
             + surf: pybamm.FullBroadcast(a, "negative electrode", "current collector"),
             "Positive "
@@ -28,7 +28,7 @@ def test_public_functions(self):
                 ["negative electrode", "separator", "positive electrode"],
                 "current collector",
             ),
-            "Cell temperature": a,
+            "Cell temperature": pybamm.Concatenation(a_n, a_s, a_p),
         }
         submodel = pybamm.electrolyte_conductivity.Full(param)
         std_tests = tests.StandardSubModelTests(submodel, variables)

tests/unit/test_models/test_submodels/test_electrolyte_conductivity/test_surface_form/test_full_surface_form_conductivity.py

@@ -31,9 +31,11 @@ def test_public_functions(self):
             "Electrolyte potential": pybamm.Concatenation(a_n, a_s, a_p),
             "Negative electrode temperature": a_n,
             "Separator temperature": a_s,
+            "Separator electrolyte concentration": a_s,
             "Positive electrode temperature": a_p,
             "Negative electrode potential": a_n,
             "Positive electrode potential": a_p,
+            "Positive electrolyte concentration": a_p,
         }
 
         spf = pybamm.electrolyte_conductivity.surface_potential_form
@@ -50,8 +52,12 @@ def test_public_functions(self):
             ),
             "Negative electrolyte potential": a_n,
             "Negative electrolyte current density": a_n,
+            "Negative electrolyte concentration": a_n,
+            "Negative electrode temperature": a_n,
             "Separator electrolyte potential": a_s,
             "Separator electrolyte current density": a_s,
+            "Separator electrolyte concentration": a_s,
+            "Separator temperature": a_s,
             "Positive electrode porosity": a_p,
             "Positive electrolyte tortuosity": a_p,
             "Positive electrode tortuosity": a_p,