diff --git a/pybop/models/lithium_ion/base_echem.py b/pybop/models/lithium_ion/base_echem.py
index cc98ad1b..774a0c96 100644
--- a/pybop/models/lithium_ion/base_echem.py
+++ b/pybop/models/lithium_ion/base_echem.py
@@ -317,9 +317,7 @@ def approximate_capacity(self, inputs: Inputs):
 
         # Calculate and update nominal capacity
         theoretical_capacity = theoretical_energy / average_voltage
-        self.parameter_set.update(
-            {"Nominal cell capacity [A.h]": theoretical_capacity}
-        )
+        self.parameter_set.update({"Nominal cell capacity [A.h]": theoretical_capacity})
 
     def set_geometric_parameters(self):
         """