Merge pull request #2751 from 1836005678/patch-2

Update NCA_Kim2011.py

pybamm/input/parameters/lithium_ion/NCA_Kim2011.py

@@ -1,5 +1,4 @@
 import pybamm
-import os
 
 
 def graphite_diffusivity_Kim2011(sto, T):
@@ -260,16 +259,34 @@ def electrolyte_conductivity_Kim2011(c_e, T):
     return sigma_e
 
 
-# Load data in the appropriate format
-path, _ = os.path.split(os.path.abspath(__file__))
-nca_ocp_Kim2011_data = pybamm.parameters.process_1D_data(
-    "nca_ocp_Kim2011_data.csv", path=path
-)
+def nca_ocp_Kim2011(sto):
+    """
+    Graphite Open Circuit Potential (OCP) as a function of the stochiometry [1].
+
+    References
+    ----------
+    .. [1] Kim, G. H., Smith, K., Lee, K. J., Santhanagopalan, S., & Pesaran, A.
+    (2011). Multi-domain modeling of lithium-ion batteries encompassing
+    multi-physics in varied length scales. Journal of The Electrochemical
+    Society, 158(8), A955-A969.
+    """
 
+    U_posi = (
+        1.638 * sto**10
+        - 2.222 * sto**9
+        + 15.056 * sto**8
+        - 23.488 * sto**7
+        + 81.246 * sto**6
+        - 344.566 * sto**5
+        + 621.3475 * sto**4
+        - 554.774 * sto**3
+        + 264.427 * sto**2
+        - 66.3691 * sto
+        + 11.8058
+        - 0.61386 * pybamm.exp(5.8201 * sto**136.4)
+    )
 
-def nca_ocp_Kim2011(sto):
-    name, (x, y) = nca_ocp_Kim2011_data
-    return pybamm.Interpolant(x, y, sto, name=name, interpolator="linear")
+    return U_posi
 
 
 # Call dict via a function to avoid errors when editing in place

tests/unit/test_experiments/test_simulation_with_experiment.py

@@ -546,6 +546,23 @@ def test_all_empty_solution_errors(self):
         with self.assertRaisesRegex(pybamm.SolverError, "All steps in the cycle"):
             sim.solve()
 
+    def test_solver_error(self):
+        model = pybamm.lithium_ion.DFN()  # load model
+        parameter_values = pybamm.ParameterValues("Chen2020")
+        experiment = pybamm.Experiment(
+            ["Discharge at 10C for 6 minutes or until 2.5 V"]
+        )
+
+        sim = pybamm.Simulation(
+            model,
+            parameter_values=parameter_values,
+            experiment=experiment,
+            solver=pybamm.CasadiSolver(mode="fast"),
+        )
+
+        with self.assertRaisesRegex(pybamm.SolverError, "IDA_CONV_FAIL"):
+            sim.solve()
+
     def test_run_experiment_half_cell(self):
         experiment = pybamm.Experiment(
             [("Discharge at C/20 until 3.5V", "Charge at 1C until 3.8 V")]

tests/unit/test_solvers/test_casadi_solver.py

@@ -491,27 +491,27 @@ def test_dae_solver_algebraic_model(self):
             solver.solve(model, t_eval)
 
     def test_interpolant_extrapolate(self):
-        model = pybamm.lithium_ion.DFN()
-        param = pybamm.ParameterValues("NCA_Kim2011")
-        experiment = pybamm.Experiment(
-            ["Charge at 1C until 4.2 V"], period="10 seconds"
-        )
+        x = np.linspace(0, 2)
+        var = pybamm.Variable("var")
+        rhs = pybamm.FunctionParameter("func", {"var": var})
 
-        param["Upper voltage cut-off [V]"] = 4.8
+        model = pybamm.BaseModel()
+        model.rhs[var] = rhs
+        model.initial_conditions[var] = pybamm.Scalar(1)
+
+        # Bug: we need to set the interpolant via parameter values for the extrapolation
+        # to be detected
+        def func(var):
+            return pybamm.Interpolant(x, x, var, interpolator="linear")
+
+        parameter_values = pybamm.ParameterValues({"func": func})
+        parameter_values.process_model(model)
+
+        solver = pybamm.CasadiSolver()
+        t_eval = [0, 5]
 
-        sim = pybamm.Simulation(
-            model,
-            parameter_values=param,
-            experiment=experiment,
-            solver=pybamm.CasadiSolver(
-                mode="safe",
-                dt_max=0.001,
-                extrap_tol=1e-3,
-                extra_options_setup={"max_num_steps": 500},
-            ),
-        )
         with self.assertRaisesRegex(pybamm.SolverError, "interpolation bounds"):
-            sim.solve()
+            solver.solve(model, t_eval)
 
     def test_casadi_safe_no_termination(self):
         model = pybamm.BaseModel()