pybamm-team · valentinsulzer · May 24, 2022 · May 5, 2022 · May 9, 2022 · May 9, 2022
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -13,6 +13,8 @@
 
 ## Breaking changes
 
+-   Changed domain-specific parameter names to a nested attribute, e.g. `param.c_n_max` is now `param.n.c_max` ([#2063](https://github.com/pybamm-team/PyBaMM/pull/2063))
+
 # [v22.3](https://github.com/pybamm-team/PyBaMM/tree/v22.3) - 2022-03-31
 
 ## Features

@@ -19,14 +19,14 @@
 def negative_radius(x):
     "Negative particle radius as a function of through-cell position (x_n [m])"
     R_n_0 = params[0]["Negative particle radius [m]"]
-    grading = 1 + 2 * x / models[1].param.L_n
+    grading = 1 + 2 * x / models[1].param.n.L
     return grading * R_n_0
 
 
 def positive_radius(x):
     "Positive particle radius as a function of through-cell position (x_p [m])"
     R_p_0 = params[0]["Positive particle radius [m]"]
-    grading = 1 + 2 * (models[1].param.L_x - x) / models[1].param.L_p
+    grading = 1 + 2 * (models[1].param.L_x - x) / models[1].param.p.L
     return grading * R_p_0
 
 

diff --git a/pybamm/expression_tree/averages.py b/pybamm/expression_tree/averages.py
@@ -154,9 +154,9 @@ def x_average(symbol):
         isinstance(child, pybamm.Broadcast) for child in symbol.children
     ):
         geo = pybamm.geometric_parameters
-        l_n = geo.l_n
-        l_s = geo.l_s
-        l_p = geo.l_p
+        l_n = geo.n.l
+        l_s = geo.s.l
+        l_p = geo.p.l
         if symbol.domain == ["negative electrode", "separator", "positive electrode"]:
             a, b, c = [orp.orphans[0] for orp in symbol.orphans]
             out = (l_n * a + l_s * b + l_p * c) / (l_n + l_s + l_p)
@@ -341,7 +341,7 @@ def size_average(symbol, f_a_dist=None):
                 "R", domains=symbol.domains, coord_sys="cartesian"
             )
             if ["negative particle size"] in symbol.domains.values():
-                f_a_dist = geo.f_a_dist_n(R)
+                f_a_dist = geo.n.f_a_dist(R)
             elif ["positive particle size"] in symbol.domains.values():
-                f_a_dist = geo.f_a_dist_p(R)
+                f_a_dist = geo.p.f_a_dist(R)
         return SizeAverage(symbol, f_a_dist)
diff --git a/pybamm/geometry/battery_geometry.py b/pybamm/geometry/battery_geometry.py
@@ -33,8 +33,8 @@ def battery_geometry(
 
     """
     geo = pybamm.geometric_parameters
-    l_n = geo.l_n
-    l_s = geo.l_s
+    l_n = geo.n.l
+    l_s = geo.s.l
     l_n_l_s = l_n + l_s
     # Override print_name
     l_n_l_s.print_name = "l_n + l_s"
@@ -55,10 +55,10 @@ def battery_geometry(
         )
     # Add particle size domains
     if options is not None and options["particle size"] == "distribution":
-        R_min_n = geo.R_min_n
-        R_min_p = geo.R_min_p
-        R_max_n = geo.R_max_n
-        R_max_p = geo.R_max_p
+        R_min_n = geo.n.R_min
+        R_min_p = geo.p.R_min
+        R_max_n = geo.n.R_max
+        R_max_p = geo.p.R_max
         geometry.update(
             {
                 "negative particle size": {"R_n": {"min": R_min_n, "max": R_max_n}},
@@ -73,8 +73,8 @@ def battery_geometry(
             geometry["current collector"] = {
                 "z": {"min": 0, "max": 1},
                 "tabs": {
-                    "negative": {"z_centre": geo.centre_z_tab_n},
-                    "positive": {"z_centre": geo.centre_z_tab_p},
+                    "negative": {"z_centre": geo.n.centre_z_tab},
+                    "positive": {"z_centre": geo.p.centre_z_tab},
                 },
             }
         elif current_collector_dimension == 2:
@@ -83,14 +83,14 @@ def battery_geometry(
                 "z": {"min": 0, "max": geo.l_z},
                 "tabs": {
                     "negative": {
-                        "y_centre": geo.centre_y_tab_n,
-                        "z_centre": geo.centre_z_tab_n,
-                        "width": geo.l_tab_n,
+                        "y_centre": geo.n.centre_y_tab,
+                        "z_centre": geo.n.centre_z_tab,
+                        "width": geo.n.l_tab,
                     },
                     "positive": {
-                        "y_centre": geo.centre_y_tab_p,
-                        "z_centre": geo.centre_z_tab_p,
-                        "width": geo.l_tab_p,
+                        "y_centre": geo.p.centre_y_tab,
+                        "z_centre": geo.p.centre_z_tab,
+                        "width": geo.p.l_tab,
                     },
                 },
             }

diff --git a/pybamm/models/full_battery_models/base_battery_model.py b/pybamm/models/full_battery_models/base_battery_model.py
@@ -1161,11 +1161,7 @@ def set_voltage_variables(self):
         # Variables for calculating the equivalent circuit model (ECM) resistance
         # Need to compare OCV to initial value to capture this as an overpotential
         ocv_init = self.param.ocv_init
-        ocv_init_dim = (
-            self.param.U_p_ref
-            - self.param.U_n_ref
-            + self.param.potential_scale * ocv_init
-        )
+        ocv_init_dim = self.param.ocv_ref + self.param.potential_scale * ocv_init
         eta_ocv = ocv - ocv_init
         eta_ocv_dim = ocv_dim - ocv_init_dim
         # Current collector current density for working out euiqvalent resistance

diff --git a/pybamm/models/full_battery_models/lead_acid/basic_full.py b/pybamm/models/full_battery_models/lead_acid/basic_full.py
@@ -102,22 +102,22 @@ def __init__(self, name="Basic full model"):
 
         # transport_efficiency
         tor = pybamm.concatenation(
-            eps_n ** param.b_e_n, eps_s ** param.b_e_s, eps_p ** param.b_e_p
+            eps_n ** param.n.b_e, eps_s ** param.s.b_e, eps_p ** param.p.b_e
         )
 
         # Interfacial reactions
-        j0_n = param.j0_n(c_e_n, T)
+        j0_n = param.n.j0(c_e_n, T)
         j_n = (
             2
             * j0_n
-            * pybamm.sinh(param.ne_n / 2 * (phi_s_n - phi_e_n - param.U_n(c_e_n, T)))
+            * pybamm.sinh(param.n.ne / 2 * (phi_s_n - phi_e_n - param.n.U(c_e_n, T)))
         )
-        j0_p = param.j0_p(c_e_p, T)
+        j0_p = param.p.j0(c_e_p, T)
         j_s = pybamm.PrimaryBroadcast(0, "separator")
         j_p = (
             2
             * j0_p
-            * pybamm.sinh(param.ne_p / 2 * (phi_s_p - phi_e_p - param.U_p(c_e_p, T)))
+            * pybamm.sinh(param.p.ne / 2 * (phi_s_p - phi_e_p - param.p.U(c_e_p, T)))
         )
         j = pybamm.concatenation(j_n, j_s, j_p)
 
@@ -136,14 +136,14 @@ def __init__(self, name="Basic full model"):
         ######################
         v_n = -pybamm.grad(pressure_n)
         v_p = -pybamm.grad(pressure_p)
-        l_s = param.l_s
-        l_n = param.l_n
+        l_s = param.s.l
+        l_n = param.n.l
         x_s = pybamm.SpatialVariable("x_s", domain="separator")
 
         # Difference in negative and positive electrode velocities determines the
         # velocity in the separator
-        v_n_right = param.beta_n * i_cell
-        v_p_left = param.beta_p * i_cell
+        v_n_right = param.n.beta * i_cell
+        v_p_left = param.p.beta * i_cell
         d_v_s__dx = (v_p_left - v_n_right) / l_s
 
         # Simple formula for velocity in the separator
@@ -159,8 +159,8 @@ def __init__(self, name="Basic full model"):
             pybamm.PrimaryBroadcast(0, "positive electrode"),
         )
         # Simple formula for velocity in the separator
-        self.algebraic[pressure_n] = pybamm.div(v_n) - param.beta_n * j_n
-        self.algebraic[pressure_p] = pybamm.div(v_p) - param.beta_p * j_p
+        self.algebraic[pressure_n] = pybamm.div(v_n) - param.n.beta * j_n
+        self.algebraic[pressure_p] = pybamm.div(v_p) - param.p.beta * j_p
         self.boundary_conditions[pressure_n] = {
             "left": (pybamm.Scalar(0), "Neumann"),
             "right": (pybamm.Scalar(0), "Dirichlet"),
@@ -183,13 +183,13 @@ def __init__(self, name="Basic full model"):
             "left": (pybamm.Scalar(0), "Neumann"),
             "right": (pybamm.Scalar(0), "Neumann"),
         }
-        self.initial_conditions[phi_e] = -param.U_n_init
+        self.initial_conditions[phi_e] = -param.n.U_init
 
         ######################
         # Current in the solid
         ######################
-        i_s_n = -param.sigma_n(T) * (1 - eps_n) ** param.b_s_n * pybamm.grad(phi_s_n)
-        sigma_eff_p = param.sigma_p(T) * (1 - eps_p) ** param.b_s_p
+        i_s_n = -param.n.sigma(T) * (1 - eps_n) ** param.n.b_s * pybamm.grad(phi_s_n)
+        sigma_eff_p = param.p.sigma(T) * (1 - eps_p) ** param.p.b_s
         i_s_p = -sigma_eff_p * pybamm.grad(phi_s_p)
         # The `algebraic` dictionary contains differential equations, with the key being
         # the main scalar variable of interest in the equation
@@ -213,9 +213,9 @@ def __init__(self, name="Basic full model"):
         # Porosity
         ######################
         beta_surf = pybamm.concatenation(
-            pybamm.PrimaryBroadcast(param.beta_surf_n, "negative electrode"),
+            pybamm.PrimaryBroadcast(param.n.beta_surf, "negative electrode"),
             pybamm.PrimaryBroadcast(0, "separator"),
-            pybamm.PrimaryBroadcast(param.beta_surf_p, "positive electrode"),
+            pybamm.PrimaryBroadcast(param.p.beta_surf, "positive electrode"),
         )
         deps_dt = -beta_surf * j
         self.rhs[eps] = deps_dt
@@ -246,9 +246,9 @@ def __init__(self, name="Basic full model"):
             + param.C_e * c_e * v
         )
         s = pybamm.concatenation(
-            pybamm.PrimaryBroadcast(param.s_plus_n_S, "negative electrode"),
+            pybamm.PrimaryBroadcast(param.n.s_plus_S, "negative electrode"),
             pybamm.PrimaryBroadcast(0, "separator"),
-            pybamm.PrimaryBroadcast(param.s_plus_p_S, "positive electrode"),
+            pybamm.PrimaryBroadcast(param.p.s_plus_S, "positive electrode"),
         )
         self.rhs[c_e] = (1 / eps) * (
             -pybamm.div(N_e) / param.C_e
@@ -279,11 +279,9 @@ def __init__(self, name="Basic full model"):
             "Electrolyte concentration": c_e,
             "Current [A]": I,
             "Negative electrode potential [V]": pot * phi_s_n,
-            "Electrolyte potential [V]": -param.U_n_ref + pot * phi_e,
-            "Positive electrode potential [V]": param.U_p_ref
-            - param.U_n_ref
-            + pot * phi_s_p,
-            "Terminal voltage [V]": param.U_p_ref - param.U_n_ref + pot * voltage,
+            "Electrolyte potential [V]": -param.n.U_ref + pot * phi_e,
+            "Positive electrode potential [V]": param.ocv_ref + pot * phi_s_p,
+            "Terminal voltage [V]": param.ocv_ref + pot * voltage,
             "Porosity": eps,
             "Volume-averaged velocity": v,
             "X-averaged separator transverse volume-averaged velocity": div_V_s,

diff --git a/pybamm/models/full_battery_models/lithium_ion/base_lithium_ion_model.py b/pybamm/models/full_battery_models/lithium_ion/base_lithium_ion_model.py
@@ -28,8 +28,8 @@ def __init__(self, options=None, name="Unnamed lithium-ion model", build=False):
             "negative electrode": self.param.L_x,
             "separator": self.param.L_x,
             "positive electrode": self.param.L_x,
-            "positive particle": self.param.R_p_typ,
-            "positive particle size": self.param.R_p_typ,
+            "positive particle": self.param.p.R_typ,
+            "positive particle size": self.param.p.R_typ,
             "current collector y": self.param.L_z,
             "current collector z": self.param.L_z,
         }
@@ -38,8 +38,8 @@ def __init__(self, options=None, name="Unnamed lithium-ion model", build=False):
         if not self.half_cell:
             self.length_scales.update(
                 {
-                    "negative particle": self.param.R_n_typ,
-                    "negative particle size": self.param.R_n_typ,
+                    "negative particle": self.param.n.R_typ,
+                    "negative particle size": self.param.n.R_typ,
                 }
             )
         self.set_standard_output_variables()
@@ -79,10 +79,10 @@ def set_standard_output_variables(self):
 
         # Particle concentration position
         var = pybamm.standard_spatial_vars
-        self.variables.update({"r_p": var.r_p, "r_p [m]": var.r_p * self.param.R_p_typ})
+        self.variables.update({"r_p": var.r_p, "r_p [m]": var.r_p * self.param.p.R_typ})
         if not self.half_cell:
             self.variables.update(
-                {"r_n": var.r_n, "r_n [m]": var.r_n * self.param.R_n_typ}
+                {"r_n": var.r_n, "r_n [m]": var.r_n * self.param.n.R_typ}
             )
 
     def set_degradation_variables(self):
@@ -96,11 +96,11 @@ def set_degradation_variables(self):
         else:
             C_n = self.variables["Negative electrode capacity [A.h]"]
             n_Li_n = self.variables["Total lithium in negative electrode [mol]"]
-            LAM_ne = (1 - C_n / param.C_n_init) * 100
+            LAM_ne = (1 - C_n / param.n.cap_init) * 100
 
         C_p = self.variables["Positive electrode capacity [A.h]"]
 
-        LAM_pe = (1 - C_p / param.C_p_init) * 100
+        LAM_pe = (1 - C_p / param.p.cap_init) * 100
 
         # LLI
         n_Li_e = self.variables["Total lithium in electrolyte [mol]"]

diff --git a/pybamm/models/full_battery_models/lithium_ion/basic_dfn.py b/pybamm/models/full_battery_models/lithium_ion/basic_dfn.py
@@ -115,30 +115,30 @@ def __init__(self, name="Doyle-Fuller-Newman model"):
 
         # transport_efficiency
         tor = pybamm.concatenation(
-            eps_n ** param.b_e_n, eps_s ** param.b_e_s, eps_p ** param.b_e_p
+            eps_n ** param.n.b_e, eps_s ** param.s.b_e, eps_p ** param.p.b_e
         )
 
         # Interfacial reactions
         # Surf takes the surface value of a variable, i.e. its boundary value on the
         # right side. This is also accessible via `boundary_value(x, "right")`, with
         # "left" providing the boundary value of the left side
         c_s_surf_n = pybamm.surf(c_s_n)
-        j0_n = param.gamma_n * param.j0_n(c_e_n, c_s_surf_n, T) / param.C_r_n
+        j0_n = param.n.gamma * param.n.j0(c_e_n, c_s_surf_n, T) / param.n.C_r
         j_n = (
             2
             * j0_n
             * pybamm.sinh(
-                param.ne_n / 2 * (phi_s_n - phi_e_n - param.U_n(c_s_surf_n, T))
+                param.n.ne / 2 * (phi_s_n - phi_e_n - param.n.U(c_s_surf_n, T))
             )
         )
         c_s_surf_p = pybamm.surf(c_s_p)
-        j0_p = param.gamma_p * param.j0_p(c_e_p, c_s_surf_p, T) / param.C_r_p
+        j0_p = param.p.gamma * param.p.j0(c_e_p, c_s_surf_p, T) / param.p.C_r
         j_s = pybamm.PrimaryBroadcast(0, "separator")
         j_p = (
             2
             * j0_p
             * pybamm.sinh(
-                param.ne_p / 2 * (phi_s_p - phi_e_p - param.U_p(c_s_surf_p, T))
+                param.p.ne / 2 * (phi_s_p - phi_e_p - param.p.U(c_s_surf_p, T))
             )
         )
         j = pybamm.concatenation(j_n, j_s, j_p)
@@ -159,35 +159,35 @@ def __init__(self, name="Doyle-Fuller-Newman model"):
 
         # The div and grad operators will be converted to the appropriate matrix
         # multiplication at the discretisation stage
-        N_s_n = -param.D_n(c_s_n, T) * pybamm.grad(c_s_n)
-        N_s_p = -param.D_p(c_s_p, T) * pybamm.grad(c_s_p)
-        self.rhs[c_s_n] = -(1 / param.C_n) * pybamm.div(N_s_n)
-        self.rhs[c_s_p] = -(1 / param.C_p) * pybamm.div(N_s_p)
+        N_s_n = -param.n.D(c_s_n, T) * pybamm.grad(c_s_n)
+        N_s_p = -param.p.D(c_s_p, T) * pybamm.grad(c_s_p)
+        self.rhs[c_s_n] = -(1 / param.n.C_diff) * pybamm.div(N_s_n)
+        self.rhs[c_s_p] = -(1 / param.p.C_diff) * pybamm.div(N_s_p)
         # Boundary conditions must be provided for equations with spatial derivatives
         self.boundary_conditions[c_s_n] = {
             "left": (pybamm.Scalar(0), "Neumann"),
             "right": (
-                -param.C_n
+                -param.n.C_diff
                 * j_n
-                / param.a_R_n
-                / param.gamma_n
-                / param.D_n(c_s_surf_n, T),
+                / param.n.a_R
+                / param.n.gamma
+                / param.n.D(c_s_surf_n, T),
                 "Neumann",
             ),
         }
         self.boundary_conditions[c_s_p] = {
             "left": (pybamm.Scalar(0), "Neumann"),
             "right": (
-                -param.C_p
+                -param.p.C_diff
                 * j_p
-                / param.a_R_p
-                / param.gamma_p
-                / param.D_p(c_s_surf_p, T),
+                / param.p.a_R
+                / param.p.gamma
+                / param.p.D(c_s_surf_p, T),
                 "Neumann",
             ),
         }
-        self.initial_conditions[c_s_n] = param.c_n_init
-        self.initial_conditions[c_s_p] = param.c_p_init
+        self.initial_conditions[c_s_n] = param.n.c_init
+        self.initial_conditions[c_s_p] = param.p.c_init
         # Events specify points at which a solution should terminate
         self.events += [
             pybamm.Event(
@@ -210,9 +210,9 @@ def __init__(self, name="Doyle-Fuller-Newman model"):
         ######################
         # Current in the solid
         ######################
-        sigma_eff_n = param.sigma_n(T) * eps_s_n ** param.b_s_n
+        sigma_eff_n = param.n.sigma(T) * eps_s_n ** param.n.b_s
         i_s_n = -sigma_eff_n * pybamm.grad(phi_s_n)
-        sigma_eff_p = param.sigma_p(T) * eps_s_p ** param.b_s_p
+        sigma_eff_p = param.p.sigma(T) * eps_s_p ** param.p.b_s
         i_s_p = -sigma_eff_p * pybamm.grad(phi_s_p)
         # The `algebraic` dictionary contains differential equations, with the key being
         # the main scalar variable of interest in the equation
@@ -245,7 +245,7 @@ def __init__(self, name="Doyle-Fuller-Newman model"):
             "left": (pybamm.Scalar(0), "Neumann"),
             "right": (pybamm.Scalar(0), "Neumann"),
         }
-        self.initial_conditions[phi_e] = -param.U_n_init
+        self.initial_conditions[phi_e] = -param.n.U_init
 
         ######################
         # Electrolyte concentration