#2669 MPM half-cell

Author: rtimms

pybamm/geometry/battery_geometry.py

@@ -44,41 +44,56 @@ def battery_geometry(
         "separator": {"x_s": {"min": l_n, "max": l_n_l_s}},
         "positive electrode": {"x_p": {"min": l_n_l_s, "max": 1}},
     }
+
     # Add particle domains
     if include_particles is True:
         zero_one = {"min": 0, "max": 1}
-        geometry.update(
-            {
-                "negative particle": {"r_n": zero_one},
-                "positive particle": {"r_p": zero_one},
-            }
-        )
         for domain in ["negative", "positive"]:
-            phases = int(getattr(options, domain)["particle phases"])
-            if phases >= 2:
+            if options.electrode_types[domain] == "porous":
                 geometry.update(
                     {
-                        f"{domain} primary particle": {"r_n_prim": zero_one},
-                        f"{domain} secondary particle": {"r_n_sec": zero_one},
+                        f"{domain} particle": {f"r_{domain[0]}": zero_one},
                     }
                 )
+                phases = int(getattr(options, domain)["particle phases"])
+                if phases >= 2:
+                    geometry.update(
+                        {
+                            f"{domain} primary particle": {
+                                f"r_{domain[0]}_prim": zero_one
+                            },
+                            f"{domain} secondary particle": {
+                                f"r_{domain[0]}_sec": zero_one
+                            },
+                        }
+                    )
+
     # Add particle size domains
-    if options is not None and options.negative["particle size"] == "distribution":
+    if (
+        options is not None
+        and options.negative["particle size"] == "distribution"
+        and options.electrode_types["negative"] == "porous"
+    ):
         R_min_n = geo.n.prim.R_min
         R_max_n = geo.n.prim.R_max
         geometry.update(
             {
                 "negative particle size": {"R_n": {"min": R_min_n, "max": R_max_n}},
             }
         )
-    if options is not None and options.positive["particle size"] == "distribution":
+    if (
+        options is not None
+        and options.positive["particle size"] == "distribution"
+        and options.electrode_types["positive"] == "porous"
+    ):
         R_min_p = geo.p.prim.R_min
         R_max_p = geo.p.prim.R_max
         geometry.update(
             {
                 "positive particle size": {"R_p": {"min": R_min_p, "max": R_max_p}},
             }
         )
+
     # Add current collector domains
     current_collector_dimension = options["dimensionality"]
     if form_factor == "pouch":

pybamm/models/full_battery_models/lithium_ion/mpm.py

@@ -54,5 +54,7 @@ def __init__(self, options=None, name="Many-Particle Model", build=True):
     @property
     def default_parameter_values(self):
         default_params = super().default_parameter_values
-        default_params = pybamm.get_size_distribution_parameters(default_params)
+        default_params = pybamm.get_size_distribution_parameters(
+            default_params, electrode=self.options["working electrode"]
+        )
         return default_params

pybamm/models/submodels/interface/kinetics/base_kinetics.py

@@ -82,7 +82,10 @@ def get_coupled_variables(self, variables):
         # Get exchange-current density
         j0 = self._get_exchange_current_density(variables)
         # Get open-circuit potential variables and reaction overpotential
-        if domain_options["particle size"] == "distribution":
+        if (
+            domain_options["particle size"] == "distribution"
+            and self.options.electrode_types[domain] == "porous"
+        ):
             ocp = variables[
                 f"{Domain} electrode {reaction_name}open circuit potential distribution"
             ]

pybamm/parameters/size_distribution_parameters.py

@@ -1,8 +1,7 @@
-"""
-Adding particle-size distribution parameter values to a parameter set
-"""
-
-
+#
+# Helper function for adding particle-size distribution parameter values
+# to a parameter set
+#
 import pybamm
 import numpy as np
 

tests/unit/test_geometry/test_battery_geometry.py

@@ -59,10 +59,10 @@ def test_geometry(self):
         self.assertEqual(geometry["negative primary particle"]["r_n_prim"]["max"], 1)
         self.assertEqual(geometry["negative secondary particle"]["r_n_sec"]["min"], 0)
         self.assertEqual(geometry["negative secondary particle"]["r_n_sec"]["max"], 1)
-        self.assertEqual(geometry["positive primary particle"]["r_n_prim"]["min"], 0)
-        self.assertEqual(geometry["positive primary particle"]["r_n_prim"]["max"], 1)
-        self.assertEqual(geometry["positive secondary particle"]["r_n_sec"]["min"], 0)
-        self.assertEqual(geometry["positive secondary particle"]["r_n_sec"]["max"], 1)
+        self.assertEqual(geometry["positive primary particle"]["r_p_prim"]["min"], 0)
+        self.assertEqual(geometry["positive primary particle"]["r_p_prim"]["max"], 1)
+        self.assertEqual(geometry["positive secondary particle"]["r_p_sec"]["min"], 0)
+        self.assertEqual(geometry["positive secondary particle"]["r_p_sec"]["max"], 1)
 
     def test_geometry_error(self):
         with self.assertRaisesRegex(pybamm.GeometryError, "Invalid current"):

tests/unit/test_models/test_full_battery_models/test_lithium_ion/test_mpm_half_cell.py

@@ -0,0 +1,80 @@
+#
+# Tests for the lithium-ion MPM model
+#
+import pybamm
+import unittest
+
+
+class TestMPM(unittest.TestCase):
+    def test_well_posed(self):
+        options = {"thermal": "isothermal", "working electrode": "positive"}
+        model = pybamm.lithium_ion.MPM(options)
+        model.check_well_posedness()
+
+        # Test build after init
+        model = pybamm.lithium_ion.MPM({"working electrode": "positive"}, build=False)
+        model.build_model()
+        model.check_well_posedness()
+
+    def test_default_parameter_values(self):
+        # check default parameters are added correctly
+        model = pybamm.lithium_ion.MPM({"working electrode": "positive"})
+        self.assertEqual(
+            model.default_parameter_values[
+                "Positive area-weighted mean particle radius [m]"
+            ],
+            5.3e-06,
+        )
+
+    def test_lumped_thermal_model_1D(self):
+        options = {"thermal": "lumped", "working electrode": "positive"}
+        model = pybamm.lithium_ion.MPM(options)
+        model.check_well_posedness()
+
+    def test_particle_uniform(self):
+        options = {"particle": "uniform profile", "working electrode": "positive"}
+        model = pybamm.lithium_ion.MPM(options)
+        model.check_well_posedness()
+
+    def test_differential_surface_form(self):
+        options = {
+            "surface form": "differential",
+            "working electrode": "positive",
+        }
+        model = pybamm.lithium_ion.MPM(options)
+        model.check_well_posedness()
+
+
+class TestMPMExternalCircuits(unittest.TestCase):
+    def test_well_posed_voltage(self):
+        options = {"operating mode": "voltage", "working electrode": "positive"}
+        model = pybamm.lithium_ion.MPM(options)
+        model.check_well_posedness()
+
+    def test_well_posed_power(self):
+        options = {"operating mode": "power", "working electrode": "positive"}
+        model = pybamm.lithium_ion.MPM(options)
+        model.check_well_posedness()
+
+    def test_well_posed_function(self):
+        def external_circuit_function(variables):
+            I = variables["Current [A]"]
+            V = variables["Terminal voltage [V]"]
+            return V + I - pybamm.FunctionParameter("Function", {"Time [s]": pybamm.t})
+
+        options = {
+            "operating mode": external_circuit_function,
+            "working electrode": "positive",
+        }
+        model = pybamm.lithium_ion.MPM(options)
+        model.check_well_posedness()
+
+
+if __name__ == "__main__":
+    print("Add -v for more debug output")
+    import sys
+
+    if "-v" in sys.argv:
+        debug = True
+    pybamm.settings.debug_mode = True
+    unittest.main()