Composite sei

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Features
 
 -   Added function `pybamm.get_git_commit_info()`, which returns information about the last git commit, useful for reproducibility ([#2293](https://github.com/pybamm-team/PyBaMM/pull/2293))
+-   Added SEI model for composite electrodes ([#2290](https://github.com/pybamm-team/PyBaMM/pull/2290))
 -   For experiments, the simulation now automatically checks and skips steps that cannot be performed (e.g. "Charge at 1C until 4.2V" from 100% SOC) ([#2212](https://github.com/pybamm-team/PyBaMM/pull/2212))
 
 ## Bug fixes

examples/notebooks/models/using-submodels.ipynb

@@ -490,8 +490,8 @@
     "model.submodels[\n",
     "    \"Positive particle mechanics\"\n",
     "] = pybamm.particle_mechanics.NoMechanics(model.param, \"Positive\", model.options)\n",
-    "model.submodels[\"sei\"] = pybamm.sei.NoSEI(model.param)\n",
-    "model.submodels[\"sei on cracks\"] = pybamm.sei.NoSEI(model.param, cracks=True)\n",
+    "model.submodels[\"sei\"] = pybamm.sei.NoSEI(model.param, model.options)\n",
+    "model.submodels[\"sei on cracks\"] = pybamm.sei.NoSEI(model.param, model.options, cracks=True)\n",
     "model.submodels[\"lithium plating\"] = pybamm.lithium_plating.NoPlating(model.param)"
    ]
   },
@@ -632,7 +632,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.8.12"
+   "version": "3.9.13"
   },
   "toc": {
    "base_numbering": 1,

examples/scripts/custom_model.py

@@ -98,8 +98,10 @@
 model.submodels["Positive particle mechanics"] = pybamm.particle_mechanics.NoMechanics(
     model.param, "Positive", model.options
 )
-model.submodels["sei"] = pybamm.sei.NoSEI(model.param)
-model.submodels["sei on cracks"] = pybamm.sei.NoSEI(model.param, cracks=True)
+model.submodels["sei"] = pybamm.sei.NoSEI(model.param, model.options)
+model.submodels["sei on cracks"] = pybamm.sei.NoSEI(
+    model.param, model.options, cracks=True
+)
 model.submodels["lithium plating"] = pybamm.lithium_plating.NoPlating(model.param)
 
 # build model

pybamm/input/discharge_data/Ecker2015/README.md

@@ -2,7 +2,7 @@
 
 Experimental data (Time [s], Terminal voltage [V]) for a 1C and 5C constant current discharge of a Kokam SLPB 75106100 cell at a temperature of 25°C from
 
->Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
+> Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
 
 The data were collected from Figure 8 of
 

pybamm/input/parameters/lithium_ion/cells/kokam_Ecker2015/README.md

@@ -4,7 +4,7 @@ Parameters for a Kokam SLPB 75106100 cell, from the papers
 
 > Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery I. determination of parameters." Journal of the Electrochemical Society 162.9 (2015): A1836-A1848.
 
->Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
+> Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
 
 The tab placement parameters are taken from measurements in
 

pybamm/input/parameters/lithium_ion/experiments/1C_discharge_from_full_Ecker2015/README.md

@@ -2,5 +2,5 @@
 
 Discharge lithium-ion battery from full charge at 1C, using the initial conditions from the paper
 
->Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857..
+> Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857..
 

pybamm/input/parameters/lithium_ion/negative_electrodes/graphite_Ecker2015/README.md

@@ -4,7 +4,7 @@ Parameters for a graphite negative electrode, from the papers:
 
 > Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery I. determination of parameters." Journal of the Electrochemical Society 162.9 (2015): A1836-A1848.
 
->Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
+> Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
 
 The fits to data for the electrode and electrolyte properties are those provided
 by Dr. Simon O’Kane in the paper:

pybamm/input/parameters/lithium_ion/positive_electrodes/LiNiCoO2_Ecker2015/README.md

@@ -4,7 +4,7 @@ Parameters for a Lithium Nickel Cobalt Oxide positive electrode, from the papers
 
 > Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery i. determination of parameters." Journal of the Electrochemical Society 162.9 (2015): A1836-A1848.
 
->Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
+> Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
 
 The fits to data for the electrode and electrolyte properties are those provided
 by Dr. Simon O’Kane in the paper:

pybamm/input/parameters/lithium_ion/seis/example_composite/README.md

@@ -0,0 +1,5 @@
+# SEI parameters
+
+Example parameters for composite SEI on silicon/graphite. Both phases use the same values, from the paper
+
+> Yang, X., Leng, Y., Zhang, G., Ge, S., Wang, C. (2017). Modeling of lithium plating induced aging of lithium-ion batteries: Transition from linear to nonlinear aging. Journal of Power Sources, 360, 28-40.

pybamm/input/parameters/lithium_ion/seis/example_composite/parameters.csv

@@ -0,0 +1,28 @@
+Name [units],Value,Reference,Notes
+# Empty rows and rows starting with ‘#’ will be ignored,,,
+,,,
+# SEI properties,,,
+Primary: Ratio of lithium moles to SEI moles,2,,Assume SEI made of LEDC and/or Li2CO3
+Primary: Inner SEI partial molar volume [m3.mol-1],9.585e-5, Safari paper,
+Primary: Outer SEI partial molar volume [m3.mol-1],9.585e-5, Safari paper,
+Primary: SEI resistivity [Ohm.m],2e5, Safari paper,
+Primary: Initial inner SEI thickness [m], 2.5E-9, 2.5E-9 1/2 of initial thickness in Safari paper,
+Primary: Initial outer SEI thickness [m], 2.5E-9, 1/2 of initial thickness in Safari paper,
+Primary: EC initial concentration in electrolyte [mol.m-3], 4.541E3, Safari paper,
+Primary: EC diffusivity [m2.s-1], 2E-18, adjusted parameter in Yang paper,
+Primary: SEI kinetic rate constant [m.s-1], 1e-12, adjusted parameter in Yang paper,
+Primary: SEI open-circuit potential [V], 0.4, Safari paper,
+Primary: SEI growth activation energy [J.mol-1], 0,,
+,,,
+Secondary: Ratio of lithium moles to SEI moles,2,,Assume SEI made of LEDC and/or Li2CO3
+Secondary: Inner SEI partial molar volume [m3.mol-1],9.585e-5, Safari paper,
+Secondary: Outer SEI partial molar volume [m3.mol-1],9.585e-5, Safari paper,
+Secondary: SEI resistivity [Ohm.m],2e5, Safari paper,
+Secondary: Initial inner SEI thickness [m], 2.5E-9, 2.5E-9 1/2 of initial thickness in Safari paper,
+Secondary: Initial outer SEI thickness [m], 2.5E-9, 1/2 of initial thickness in Safari paper,
+Secondary: EC initial concentration in electrolyte [mol.m-3], 4.541E3, Safari paper,
+Secondary: EC diffusivity [m2.s-1], 2E-18, adjusted parameter in Yang paper,
+Secondary: SEI kinetic rate constant [m.s-1], 1e-12, adjusted parameter in Yang paper,
+Secondary: SEI open-circuit potential [V], 0.4, Safari paper,
+Secondary: SEI growth activation energy [J.mol-1], 0,,
+,,,

pybamm/input/parameters/lithium_ion/separators/separator_Ecker2015/README.md

@@ -4,7 +4,7 @@ Parameters for the separator from the papers
 
 > Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery i. determination of parameters." Journal of the Electrochemical Society 162.9 (2015): A1836-A1848.
 
->Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
+> Ecker, Madeleine, et al. "Parameterization of a physico-chemical model of a lithium-ion battery II. Model validation." Journal of The Electrochemical Society 162.9 (2015): A1849-A1857.
 
 The thermal material properties are for a 5 Ah power pouch cell by Kokam. The data are extracted from
 

pybamm/models/full_battery_models/base_battery_model.py

@@ -510,7 +510,6 @@ def __init__(self, extra_options):
                 options["surface form"] != "false"
                 and options["particle size"] == "single"
                 and options["particle"] == "Fickian diffusion"
-                and options["SEI"] == "none"
                 and options["particle mechanics"] == "none"
                 and options["loss of active material"] == "none"
                 and options["lithium plating"] == "none"
@@ -519,7 +518,7 @@ def __init__(self, extra_options):
                     "If there are multiple particle phases: 'surface form' cannot be "
                     "'false', 'particle size' must be 'false', 'particle' must be "
                     "'Fickian diffusion'. Also the following must "
-                    "be 'none': 'SEI', 'particle mechanics', "
+                    "be 'none': 'particle mechanics', "
                     "'loss of active material', 'lithium plating'"
                 )
 
@@ -1256,8 +1255,10 @@ def set_voltage_variables(self):
             eta_sei_av = self.variables["SEI film overpotential"]
             eta_sei_av_dim = self.variables["SEI film overpotential [V]"]
         else:
-            eta_sei_av = self.variables["X-averaged SEI film overpotential"]
-            eta_sei_av_dim = self.variables["X-averaged SEI film overpotential [V]"]
+            eta_sei_av = self.variables[f"X-averaged {phase_n}SEI film overpotential"]
+            eta_sei_av_dim = self.variables[
+                f"X-averaged {phase_n}SEI film overpotential [V]"
+            ]
 
         # TODO: add current collector losses to the voltage in 3D
 

pybamm/models/full_battery_models/lead_acid/base_lead_acid_model.py

@@ -104,7 +104,7 @@ def set_active_material_submodel(self):
 
     def set_sei_submodel(self):
 
-        self.submodels["sei"] = pybamm.sei.NoSEI(self.param)
+        self.submodels["sei"] = pybamm.sei.NoSEI(self.param, self.options)
 
     def set_lithium_plating_submodel(self):
 

pybamm/models/full_battery_models/lithium_ion/base_lithium_ion_model.py

@@ -269,28 +269,38 @@ def set_sei_submodel(self):
         else:
             reaction_loc = "full electrode"
 
-        if self.options["SEI"] == "none":
-            self.submodels["sei"] = pybamm.sei.NoSEI(self.param, self.options)
-        elif self.options["SEI"] == "constant":
-            self.submodels["sei"] = pybamm.sei.ConstantSEI(self.param, self.options)
-        else:
-            self.submodels["sei"] = pybamm.sei.SEIGrowth(
-                self.param, reaction_loc, self.options, cracks=False
-            )
-        # Do not set "sei on cracks" submodel for half-cells
-        # For full cells, "sei on cracks" submodel must be set, even if it is zero
-        if reaction_loc != "interface":
-            if (
-                self.options["SEI"] in ["none", "constant"]
-                or self.options["SEI on cracks"] == "false"
-            ):
-                self.submodels["sei on cracks"] = pybamm.sei.NoSEI(
-                    self.param, self.options, cracks=True
-                )
+        phases = self.options.phases["negative"]
+        for phase in phases:
+            if self.options["SEI"] == "none":
+                submodel = pybamm.sei.NoSEI(self.param, self.options, phase)
+            elif self.options["SEI"] == "constant":
+                submodel = pybamm.sei.ConstantSEI(self.param, self.options, phase)
             else:
-                self.submodels["sei on cracks"] = pybamm.sei.SEIGrowth(
-                    self.param, reaction_loc, self.options, cracks=True
+                submodel = pybamm.sei.SEIGrowth(
+                    self.param, reaction_loc, self.options, phase, cracks=False
                 )
+            self.submodels[f"{phase} sei"] = submodel
+            # Do not set "sei on cracks" submodel for half-cells
+            # For full cells, "sei on cracks" submodel must be set, even if it is zero
+            if reaction_loc != "interface":
+                if (
+                    self.options["SEI"] in ["none", "constant"]
+                    or self.options["SEI on cracks"] == "false"
+                ):
+                    submodel = pybamm.sei.NoSEI(
+                        self.param, self.options, phase, cracks=True
+                    )
+                else:
+                    submodel = pybamm.sei.SEIGrowth(
+                        self.param, reaction_loc, self.options, phase, cracks=True
+                    )
+                self.submodels[f"{phase} sei on cracks"] = submodel
+
+        if len(phases) > 1:
+            self.submodels["total sei"] = pybamm.sei.TotalSEI(self.param, self.options)
+            self.submodels["total sei on cracks"] = pybamm.sei.TotalSEI(
+                self.param, self.options, cracks=True
+            )
 
     def set_lithium_plating_submodel(self):
         if self.options["lithium plating"] == "none":

pybamm/models/full_battery_models/lithium_ion/dfn.py

@@ -59,17 +59,19 @@ def set_convection_submodel(self):
     def set_intercalation_kinetics_submodel(self):
         for domain in ["negative", "positive"]:
             intercalation_kinetics = self.get_intercalation_kinetics(domain)
-            for phase in self.options.phases[domain]:
+            phases = self.options.phases[domain]
+            for phase in phases:
                 submod = intercalation_kinetics(
                     self.param, domain, "lithium-ion main", self.options, phase
                 )
                 self.submodels[f"{domain.lower()} {phase} interface"] = submod
 
-            self.submodels[
-                f"total {domain} interface"
-            ] = pybamm.kinetics.TotalMainKinetics(
-                self.param, domain, "lithium-ion main", self.options
-            )
+            if len(phases) > 1:
+                self.submodels[
+                    f"total {domain} interface"
+                ] = pybamm.kinetics.TotalMainKinetics(
+                    self.param, domain, "lithium-ion main", self.options
+                )
 
     def set_particle_submodel(self):
         for domain in ["negative", "positive"]:

pybamm/models/full_battery_models/lithium_ion/spm.py

@@ -95,16 +95,18 @@ def set_intercalation_kinetics_submodel(self):
                 )
             else:
                 intercalation_kinetics = self.get_intercalation_kinetics(domain)
-                for phase in self.options.phases[domain]:
+                phases = self.options.phases[domain]
+                for phase in phases:
                     submod = intercalation_kinetics(
                         self.param, domain, "lithium-ion main", self.options, phase
                     )
                     self.submodels[f"{domain} {phase} interface"] = submod
-                self.submodels[
-                    f"total {domain} interface"
-                ] = pybamm.kinetics.TotalMainKinetics(
-                    self.param, domain, "lithium-ion main", self.options
-                )
+                if len(phases) > 1:
+                    self.submodels[
+                        f"total {domain} interface"
+                    ] = pybamm.kinetics.TotalMainKinetics(
+                        self.param, domain, "lithium-ion main", self.options
+                    )
 
     def set_particle_submodel(self):
         for domain in ["negative", "positive"]:

pybamm/models/standard_variables.py

@@ -199,35 +199,6 @@ def __init__(self):
         )
         self.T_vol_av = pybamm.Variable("Volume-averaged cell temperature")
 
-        # SEI variables
-        self.L_inner_av = pybamm.Variable(
-            "X-averaged inner SEI thickness",
-            domain="current collector",
-        )
-        self.L_inner = pybamm.Variable(
-            "Inner SEI thickness",
-            domain=["negative electrode"],
-            auxiliary_domains={"secondary": "current collector"},
-        )
-        self.L_outer_av = pybamm.Variable(
-            "X-averaged outer SEI thickness",
-            domain="current collector",
-        )
-        self.L_outer = pybamm.Variable(
-            "Outer SEI thickness",
-            domain=["negative electrode"],
-            auxiliary_domains={"secondary": "current collector"},
-        )
-        # For SEI reaction at the li metal/separator interface in a li metal model
-        self.L_inner_interface = pybamm.Variable(
-            "Inner SEI thickness",
-            domain=["current collector"],
-        )
-        self.L_outer_interface = pybamm.Variable(
-            "Outer SEI thickness",
-            domain=["current collector"],
-        )
-
         # Interface utilisation
         self.u_n = pybamm.Variable(
             "Negative electrode interface utilisation",

pybamm/models/submodels/active_material/total_active_material.py

@@ -29,51 +29,25 @@ def get_coupled_variables(self, variables):
         domain = Domain.lower()
 
         phases = self.options.phases[domain]
-        eps_solid = sum(
-            variables[f"{Domain} electrode {phase} active material volume fraction"]
-            for phase in phases
-        )
-        eps_solid_av = sum(
-            variables[
-                f"X-averaged {domain} electrode {phase} active material volume fraction"
-            ]
-            for phase in phases
-        )
-        variables.update(
-            {
-                f"{Domain} electrode active material volume fraction": eps_solid,
-                f"X-averaged {domain} electrode active material volume fraction"
-                "": eps_solid_av,
-            }
-        )
+        # For each of the variables, the variable name without the phase name
+        # is constructed by summing all of the variable names with the phases
+        for variable_template in [
+            f"{Domain} electrode {{}}active material volume fraction",
+            f"X-averaged {domain} electrode {{}}active material volume fraction",
+            f"{Domain} electrode {{}}active material volume fraction change",
+            f"X-averaged {domain} electrode {{}}active material volume fraction change",
+        ]:
+            sumvar = sum(
+                variables[variable_template.format(phase + " ")] for phase in phases
+            )
+            variables[variable_template.format("")] = sumvar
 
         if self.options["particle shape"] != "no particles":
+            # capacity doesn't fit the template so needs to be done separately
             C = sum(
                 variables[f"{Domain} electrode {phase} phase capacity [A.h]"]
                 for phase in phases
             )
             variables.update({f"{Domain} electrode capacity [A.h]": C})
 
-        deps_solid_dt = sum(
-            variables[
-                f"{Domain} electrode {phase} active material volume fraction change"
-            ]
-            for phase in phases
-        )
-        deps_solid_dt_av = sum(
-            variables[
-                f"X-averaged {domain} electrode {phase} active material "
-                "volume fraction change"
-            ]
-            for phase in phases
-        )
-        variables.update(
-            {
-                f"{Domain} electrode active material volume fraction change"
-                "": deps_solid_dt,
-                f"X-averaged {domain} electrode active material volume fraction change"
-                "": deps_solid_dt_av,
-            }
-        )
-
         return variables