diff --git a/examples/scripts/compare_lithium_ion.py b/examples/scripts/compare_lithium_ion.py
index 507ed5dc5d..53459a036c 100644
--- a/examples/scripts/compare_lithium_ion.py
+++ b/examples/scripts/compare_lithium_ion.py
@@ -16,7 +16,7 @@
     pybamm.set_logging_level("INFO")
 
 # load models
-options = {"thermal": "isothermal", "surface form": "differential"}
+options = {"thermal": "isothermal"}
 models = [
     pybamm.lithium_ion.SPM(options),
     pybamm.lithium_ion.SPMe(options),