Merge pull request #1790 from pybamm-team/issue-1489-surface-area

#1489 add surface area to volume ratio factor
pybamm-team · Nov 9, 2021 · 884d6e9 · 884d6e9
2 parents dd77bec + 1de9c11
commit 884d6e9
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diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -2,7 +2,9 @@
 
 ## Features
 
--   Half-cell SPM and SPMe have been implemented (  [#1731](https://github.com/pybamm-team/PyBaMM/pull/1731))
+-   Added surface area to volume ratio as a factor to the SEI equations ([#1790](https://github.com/pybamm-team/PyBaMM/pull/1790))
+-   Half-cell SPM and SPMe have been implemented ([#1731](https://github.com/pybamm-team/PyBaMM/pull/1731))
+
 ## Bug fixes
 
 -   Fixed `sympy` operators for `Arctan` and `Exponential` ([#1786](https://github.com/pybamm-team/PyBaMM/pull/1786))
@@ -11,6 +13,7 @@
 ## Breaking changes
 
 -   Raise error if `Concatenation` is used directly with `Variable` objects (`concatenation` should be used instead) ([#1789](https://github.com/pybamm-team/PyBaMM/pull/1789))
+
 # [v21.10](https://github.com/pybamm-team/PyBaMM/tree/v21.9) - 2021-10-31
 
 ## Features

diff --git a/examples/scripts/compare_lithium_ion_half_cell.py b/examples/scripts/compare_lithium_ion_half_cell.py
@@ -7,9 +7,15 @@
 
 # load models
 models = [
-    pybamm.lithium_ion.SPM({"working electrode": "positive"}),
-    pybamm.lithium_ion.SPMe({"working electrode": "positive"}),
-    pybamm.lithium_ion.DFN({"working electrode": "positive"}),
+    pybamm.lithium_ion.SPM(
+        {"working electrode": "positive", "SEI": "ec reaction limited"}
+    ),
+    pybamm.lithium_ion.SPMe(
+        {"working electrode": "positive", "SEI": "ec reaction limited"}
+    ),
+    pybamm.lithium_ion.DFN(
+        {"working electrode": "positive", "SEI": "ec reaction limited"}
+    ),
 ]
 
 chemistry = pybamm.parameter_sets.Xu2019

diff --git a/pybamm/models/submodels/interface/lithium_plating/irreversible_plating.py b/pybamm/models/submodels/interface/lithium_plating/irreversible_plating.py
@@ -77,12 +77,17 @@ def set_rhs(self, variables):
             j_stripping = variables[
                 "X-averaged lithium plating interfacial current density"
             ]
+            # Note a is dimensionless (has a constant value of 1 if the surface
+            # area does not change)
+            a = variables["X-averaged negative electrode surface area to volume ratio"]
         else:
             c_plated_Li = variables["Lithium plating concentration"]
             j_stripping = variables["Lithium plating interfacial current density"]
+            a = variables["Negative electrode surface area to volume ratio"]
 
         Gamma_plating = self.param.Gamma_plating
-        self.rhs = {c_plated_Li: -Gamma_plating * j_stripping}
+
+        self.rhs = {c_plated_Li: -Gamma_plating * a * j_stripping}
 
     def set_initial_conditions(self, variables):
         if self.x_average is True:

diff --git a/pybamm/models/submodels/interface/lithium_plating/reversible_plating.py b/pybamm/models/submodels/interface/lithium_plating/reversible_plating.py
@@ -77,12 +77,17 @@ def set_rhs(self, variables):
             j_stripping = variables[
                 "X-averaged lithium plating interfacial current density"
             ]
+            # Note a is dimensionless (has a constant value of 1 if the surface
+            # area does not change)
+            a = variables["X-averaged negative electrode surface area to volume ratio"]
         else:
             c_plated_Li = variables["Lithium plating concentration"]
             j_stripping = variables["Lithium plating interfacial current density"]
+            a = variables["Negative electrode surface area to volume ratio"]
 
         Gamma_plating = self.param.Gamma_plating
-        self.rhs = {c_plated_Li: -Gamma_plating * j_stripping}
+
+        self.rhs = {c_plated_Li: -Gamma_plating * a * j_stripping}
 
     def set_initial_conditions(self, variables):
         if self.x_average is True:

diff --git a/pybamm/models/submodels/interface/sei/ec_reaction_limited.py b/pybamm/models/submodels/interface/sei/ec_reaction_limited.py
@@ -119,13 +119,20 @@ def set_rhs(self, variables):
         if self.reaction_loc == "x-average":
             L_sei = variables["X-averaged outer SEI thickness"]
             j_sei = variables["X-averaged outer SEI interfacial current density"]
+            # Note a is dimensionless (has a constant value of 1 if the surface
+            # area does not change)
+            a = variables["X-averaged negative electrode surface area to volume ratio"]
         else:
             L_sei = variables["Outer SEI thickness"]
             j_sei = variables["Outer SEI interfacial current density"]
+            if self.reaction_loc == "interface":
+                a = 1
+            else:
+                a = variables["Negative electrode surface area to volume ratio"]
 
         Gamma_SEI = self.param.Gamma_SEI
 
-        self.rhs = {L_sei: -Gamma_SEI * j_sei / 2}
+        self.rhs = {L_sei: -Gamma_SEI * a * j_sei / 2}
 
     def set_initial_conditions(self, variables):
         if self.reaction_loc == "x-average":

diff --git a/pybamm/models/submodels/interface/sei/electron_migration_limited.py b/pybamm/models/submodels/interface/sei/electron_migration_limited.py
@@ -73,18 +73,25 @@ def set_rhs(self, variables):
             L_outer = variables["X-averaged outer SEI thickness"]
             j_inner = variables["X-averaged inner SEI interfacial current density"]
             j_outer = variables["X-averaged outer SEI interfacial current density"]
+            # Note a is dimensionless (has a constant value of 1 if the surface
+            # area does not change)
+            a = variables["X-averaged negative electrode surface area to volume ratio"]
         else:
             L_inner = variables["Inner SEI thickness"]
             L_outer = variables["Outer SEI thickness"]
             j_inner = variables["Inner SEI interfacial current density"]
             j_outer = variables["Outer SEI interfacial current density"]
+            if self.reaction_loc == "interface":
+                a = 1
+            else:
+                a = variables["Negative electrode surface area to volume ratio"]
 
         v_bar = self.param.v_bar
         Gamma_SEI = self.param.Gamma_SEI
 
         self.rhs = {
-            L_inner: -Gamma_SEI * j_inner,
-            L_outer: -v_bar * Gamma_SEI * j_outer,
+            L_inner: -Gamma_SEI * a * j_inner,
+            L_outer: -v_bar * Gamma_SEI * a * j_outer,
         }
 
     def set_initial_conditions(self, variables):

diff --git a/pybamm/models/submodels/interface/sei/interstitial_diffusion_limited.py b/pybamm/models/submodels/interface/sei/interstitial_diffusion_limited.py
@@ -75,19 +75,25 @@ def set_rhs(self, variables):
             L_outer = variables["X-averaged outer SEI thickness"]
             j_inner = variables["X-averaged inner SEI interfacial current density"]
             j_outer = variables["X-averaged outer SEI interfacial current density"]
+            # Note a is dimensionless (has a constant value of 1 if the surface
+            # area does not change)
+            a = variables["X-averaged negative electrode surface area to volume ratio"]
         else:
             L_inner = variables["Inner SEI thickness"]
             L_outer = variables["Outer SEI thickness"]
             j_inner = variables["Inner SEI interfacial current density"]
             j_outer = variables["Outer SEI interfacial current density"]
+            if self.reaction_loc == "interface":
+                a = 1
+            else:
+                a = variables["Negative electrode surface area to volume ratio"]
 
         v_bar = self.param.v_bar
-
         Gamma_SEI = self.param.Gamma_SEI
 
         self.rhs = {
-            L_inner: -Gamma_SEI * j_inner,
-            L_outer: -v_bar * Gamma_SEI * j_outer,
+            L_inner: -Gamma_SEI * a * j_inner,
+            L_outer: -v_bar * Gamma_SEI * a * j_outer,
         }
 
     def set_initial_conditions(self, variables):

diff --git a/pybamm/models/submodels/interface/sei/reaction_limited.py b/pybamm/models/submodels/interface/sei/reaction_limited.py
@@ -95,18 +95,25 @@ def set_rhs(self, variables):
             L_outer = variables["X-averaged outer SEI thickness"]
             j_inner = variables["X-averaged inner SEI interfacial current density"]
             j_outer = variables["X-averaged outer SEI interfacial current density"]
+            # Note a is dimensionless (has a constant value of 1 if the surface
+            # area does not change)
+            a = variables["X-averaged negative electrode surface area to volume ratio"]
         else:
             L_inner = variables["Inner SEI thickness"]
             L_outer = variables["Outer SEI thickness"]
             j_inner = variables["Inner SEI interfacial current density"]
             j_outer = variables["Outer SEI interfacial current density"]
+            if self.reaction_loc == "interface":
+                a = 1
+            else:
+                a = variables["Negative electrode surface area to volume ratio"]
 
         v_bar = self.param.v_bar
         Gamma_SEI = self.param.Gamma_SEI
 
         self.rhs = {
-            L_inner: -Gamma_SEI * j_inner,
-            L_outer: -v_bar * Gamma_SEI * j_outer,
+            L_inner: -Gamma_SEI * a * j_inner,
+            L_outer: -v_bar * Gamma_SEI * a * j_outer,
         }
 
     def set_initial_conditions(self, variables):

diff --git a/pybamm/models/submodels/interface/sei/solvent_diffusion_limited.py b/pybamm/models/submodels/interface/sei/solvent_diffusion_limited.py
@@ -68,18 +68,25 @@ def set_rhs(self, variables):
             L_outer = variables["X-averaged outer SEI thickness"]
             j_inner = variables["X-averaged inner SEI interfacial current density"]
             j_outer = variables["X-averaged outer SEI interfacial current density"]
+            # Note a is dimensionless (has a constant value of 1 if the surface
+            # area does not change)
+            a = variables["X-averaged negative electrode surface area to volume ratio"]
         else:
             L_inner = variables["Inner SEI thickness"]
             L_outer = variables["Outer SEI thickness"]
             j_inner = variables["Inner SEI interfacial current density"]
             j_outer = variables["Outer SEI interfacial current density"]
-        v_bar = self.param.v_bar
+            if self.reaction_loc == "interface":
+                a = 1
+            else:
+                a = variables["Negative electrode surface area to volume ratio"]
 
+        v_bar = self.param.v_bar
         Gamma_SEI = self.param.Gamma_SEI
 
         self.rhs = {
-            L_inner: -Gamma_SEI * j_inner,
-            L_outer: -v_bar * Gamma_SEI * j_outer,
+            L_inner: -Gamma_SEI * a * j_inner,
+            L_outer: -v_bar * Gamma_SEI * a * j_outer,
         }
 
     def set_initial_conditions(self, variables):