diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0d7bb2309..fc47c4c40 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@
 
 ## Optimizations
 
+-   Changed default solver for DAE models to `CasadiSolver` ([#978](https://github.com/pybamm-team/PyBaMM/pull/978))
 -   Added some extra simplifications to the expression tree ([#971](https://github.com/pybamm-team/PyBaMM/pull/971))
 -   Changed the behaviour of "safe" mode in `CasadiSolver` ([#956](https://github.com/pybamm-team/PyBaMM/pull/956))
 -   Sped up model building ([#927](https://github.com/pybamm-team/PyBaMM/pull/927))
diff --git a/pybamm/models/base_model.py b/pybamm/models/base_model.py
index 2a16c024a..44f5cf29e 100644
--- a/pybamm/models/base_model.py
+++ b/pybamm/models/base_model.py
@@ -651,9 +651,6 @@ class BaseModel(object):
         "Return default solver based on whether model is ODE model or DAE model"
         if len(self.algebraic) == 0:
             return pybamm.ScipySolver()
-        elif pybamm.have_idaklu() and self.use_jacobian is True:
-            # KLU solver requires jacobian to be provided
-            return pybamm.IDAKLUSolver()
         else:
             return pybamm.CasadiSolver(mode="safe")
 
@@ -677,11 +674,7 @@ def find_symbol_in_dict(dic, name):
 
 
 def find_symbol_in_model(model, name):
-    dics = [
-        model.rhs,
-        model.algebraic,
-        model.variables,
-    ]
+    dics = [model.rhs, model.algebraic, model.variables]
     for dic in dics:
         dic_return = find_symbol_in_dict(dic, name)
         if dic_return:
diff --git a/pybamm/models/full_battery_models/lead_acid/base_lead_acid_model.py b/pybamm/models/full_battery_models/lead_acid/base_lead_acid_model.py
index bbf97bf0d..990434414 100644
--- a/pybamm/models/full_battery_models/lead_acid/base_lead_acid_model.py
+++ b/pybamm/models/full_battery_models/lead_acid/base_lead_acid_model.py
@@ -42,17 +42,6 @@ class BaseModel(pybamm.BaseBatteryModel):
         var = pybamm.standard_spatial_vars
         return {var.x_n: 25, var.x_s: 41, var.x_p: 34, var.y: 10, var.z: 10}
 
-    @property
-    def default_solver(self):
-        """
-        Return default solver based on whether model is ODE model or DAE model.
-        There are bugs with KLU on the lead-acid models.
-        """
-        if len(self.algebraic) == 0:
-            return pybamm.ScipySolver()
-        else:
-            return pybamm.CasadiSolver(mode="safe")
-
     def set_soc_variables(self):
         "Set variables relating to the state of charge."
         # State of Charge defined as function of dimensionless electrolyte concentration
diff --git a/pybamm/models/submodels/current_collector/effective_resistance_current_collector.py b/pybamm/models/submodels/current_collector/effective_resistance_current_collector.py
index 26819f11f..e74fe39cb 100644
--- a/pybamm/models/submodels/current_collector/effective_resistance_current_collector.py
+++ b/pybamm/models/submodels/current_collector/effective_resistance_current_collector.py
@@ -217,4 +217,4 @@ class EffectiveResistance2D(pybamm.BaseModel):
 
     @property
     def default_solver(self):
-        return pybamm.AlgebraicSolver()
+        return pybamm.CasadiAlgebraicSolver()

Default Solver Casadi
Make casadi the default solver
diff --git a/tests/unit/test_models/test_submodels/test_current_collector/test_effective_current_collector.py b/tests/unit/test_models/test_submodels/test_current_collector/test_effective_current_collector.py
index 352d6a726..66a17b5a1 100644
--- a/tests/unit/test_models/test_submodels/test_current_collector/test_effective_current_collector.py
+++ b/tests/unit/test_models/test_submodels/test_current_collector/test_effective_current_collector.py
@@ -19,7 +19,7 @@ class TestEffectiveResistance2D(unittest.TestCase):
 
     def test_default_solver(self):
         model = pybamm.current_collector.EffectiveResistance2D()
-        self.assertIsInstance(model.default_solver, pybamm.AlgebraicSolver)
+        self.assertIsInstance(model.default_solver, pybamm.CasadiAlgebraicSolver)
 
     def test_get_processed_potentials(self):
         # solve cheap SPM to test processed potentials (think of an alternative test?)

pip install -e .[dev,docs]
parse_log_pytest
requirements.txt
pytest
3.7
requirements.txt
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
aiofiles==22.1.0
aiosqlite==0.19.0
alabaster==0.7.13
anyio==3.7.1
anytree==2.12.1
argon2-cffi==23.1.0
argon2-cffi-bindings==21.2.0
arrow==1.2.3
attrs==24.2.0
autograd==1.6.2
Babel==2.14.0
backcall==0.2.0
beautifulsoup4==4.13.3
black==23.3.0
bleach==6.0.0
cached-property==1.5.2
casadi==3.7.0
certifi @ file:///croot/certifi_1671487769961/work/certifi
cffi==1.15.1
charset-normalizer==3.4.1
click==8.1.8
comm==0.1.4
cycler==0.11.0
debugpy==1.7.0
decorator==5.1.1
defusedxml==0.7.1
docutils==0.17.1
entrypoints==0.4
exceptiongroup==1.2.2
fastjsonschema==2.21.1
flake8==5.0.4
fonttools==4.38.0
fqdn==1.5.1
future==1.0.0
guzzle-sphinx-theme==0.7.11
idna==3.10
imagesize==1.4.1
importlib-metadata==4.2.0
importlib-resources==5.12.0
iniconfig==2.0.0
ipykernel==6.16.2
ipython==7.34.0
ipython-genutils==0.2.0
ipywidgets==8.1.5
isoduration==20.11.0
jedi==0.19.2
Jinja2==3.1.6
json5==0.9.16
jsonpointer==3.0.0
jsonschema==4.17.3
jupyter==1.1.1
jupyter-console==6.6.3
jupyter-events==0.6.3
jupyter-server==1.24.0
jupyter-ydoc==0.2.5
jupyter_client==7.4.9
jupyter_core==4.12.0
jupyter_server_fileid==0.9.3
jupyter_server_ydoc==0.8.0
jupyterlab==3.5.3
jupyterlab-pygments==0.2.2
jupyterlab_server==2.15.2
jupyterlab_widgets==3.0.13
kiwisolver==1.4.5
MarkupSafe==2.1.5
matplotlib==3.5.3
matplotlib-inline==0.1.6
mccabe==0.7.0
mistune==3.0.2
mypy-extensions==1.0.0
nbclassic==1.2.0
nbclient==0.7.4
nbconvert==7.6.0
nbformat==5.8.0
nest-asyncio==1.6.0
notebook==6.5.7
notebook_shim==0.2.4
numpy==1.21.6
packaging==24.0
pandas==1.3.5
pandocfilters==1.5.1
parso==0.8.4
pathspec==0.11.2
pexpect==4.9.0
pickleshare==0.7.5
Pillow==9.5.0
pkgutil_resolve_name==1.3.10
platformdirs==4.0.0
pluggy==1.2.0
prometheus-client==0.17.1
prompt_toolkit==3.0.48
psutil==7.0.0
ptyprocess==0.7.0
-e git+https://github.com/pybamm-team/PyBaMM.git@83fba98eea5890a900cd76f2d16766147d8430e1#egg=pybamm
pycodestyle==2.9.1
pycparser==2.21
pyflakes==2.5.0
Pygments==2.17.2
pyparsing==3.1.4
pyrsistent==0.19.3
pytest==7.4.4
python-dateutil==2.9.0.post0
python-json-logger==3.0.1
pytz==2025.2
PyYAML==6.0.1
pyzmq==26.2.1
requests==2.31.0
rfc3339-validator==0.1.4
rfc3986-validator==0.1.1
scikit-fem==8.1.0
scipy==1.7.3
Send2Trash==1.8.3
six==1.17.0
sniffio==1.3.1
snowballstemmer==2.2.0
soupsieve==2.4.1
Sphinx==4.3.2
sphinxcontrib-applehelp==1.0.2
sphinxcontrib-devhelp==1.0.2
sphinxcontrib-htmlhelp==2.0.0
sphinxcontrib-jsmath==1.0.1
sphinxcontrib-qthelp==1.0.3
sphinxcontrib-serializinghtml==1.1.5
terminado==0.17.1
tinycss2==1.2.1
tomli==2.0.1
tornado==6.2
traitlets==5.9.0
typed-ast==1.5.5
typing_extensions==4.7.1
uri-template==1.3.0
urllib3==2.0.7
wcwidth==0.2.13
webcolors==1.13
webencodings==0.5.1
websocket-client==1.6.1
widgetsnbextension==4.0.13
y-py==0.6.2
ypy-websocket==0.8.4
zipp==3.15.0

name: PyBaMM
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - ca-certificates=2025.2.25=h06a4308_0
  - certifi=2022.12.7=py37h06a4308_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.4.4=h6a678d5_1
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - ncurses=6.4=h6a678d5_0
  - openssl=1.1.1w=h7f8727e_0
  - pip=22.3.1=py37h06a4308_0
  - python=3.7.16=h7a1cb2a_0
  - readline=8.2=h5eee18b_0
  - setuptools=65.6.3=py37h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - wheel=0.38.4=py37h06a4308_0
  - xz=5.6.4=h5eee18b_1
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - aiofiles==22.1.0
      - aiosqlite==0.19.0
      - alabaster==0.7.13
      - anyio==3.7.1
      - anytree==2.12.1
      - argon2-cffi==23.1.0
      - argon2-cffi-bindings==21.2.0
      - arrow==1.2.3
      - attrs==24.2.0
      - autograd==1.6.2
      - babel==2.14.0
      - backcall==0.2.0
      - beautifulsoup4==4.13.3
      - black==23.3.0
      - bleach==6.0.0
      - cached-property==1.5.2
      - casadi==3.7.0
      - cffi==1.15.1
      - charset-normalizer==3.4.1
      - click==8.1.8
      - comm==0.1.4
      - cycler==0.11.0
      - debugpy==1.7.0
      - decorator==5.1.1
      - defusedxml==0.7.1
      - docutils==0.17.1
      - entrypoints==0.4
      - exceptiongroup==1.2.2
      - fastjsonschema==2.21.1
      - flake8==5.0.4
      - fonttools==4.38.0
      - fqdn==1.5.1
      - future==1.0.0
      - guzzle-sphinx-theme==0.7.11
      - idna==3.10
      - imagesize==1.4.1
      - importlib-metadata==4.2.0
      - importlib-resources==5.12.0
      - iniconfig==2.0.0
      - ipykernel==6.16.2
      - ipython==7.34.0
      - ipython-genutils==0.2.0
      - ipywidgets==8.1.5
      - isoduration==20.11.0
      - jedi==0.19.2
      - jinja2==3.1.6
      - json5==0.9.16
      - jsonpointer==3.0.0
      - jsonschema==4.17.3
      - jupyter==1.1.1
      - jupyter-client==7.4.9
      - jupyter-console==6.6.3
      - jupyter-core==4.12.0
      - jupyter-events==0.6.3
      - jupyter-server==1.24.0
      - jupyter-server-fileid==0.9.3
      - jupyter-server-ydoc==0.8.0
      - jupyter-ydoc==0.2.5
      - jupyterlab==3.5.3
      - jupyterlab-pygments==0.2.2
      - jupyterlab-server==2.15.2
      - jupyterlab-widgets==3.0.13
      - kiwisolver==1.4.5
      - markupsafe==2.1.5
      - matplotlib==3.5.3
      - matplotlib-inline==0.1.6
      - mccabe==0.7.0
      - mistune==3.0.2
      - mypy-extensions==1.0.0
      - nbclassic==1.2.0
      - nbclient==0.7.4
      - nbconvert==7.6.0
      - nbformat==5.8.0
      - nest-asyncio==1.6.0
      - notebook==6.5.7
      - notebook-shim==0.2.4
      - numpy==1.21.6
      - packaging==24.0
      - pandas==1.3.5
      - pandocfilters==1.5.1
      - parso==0.8.4
      - pathspec==0.11.2
      - pexpect==4.9.0
      - pickleshare==0.7.5
      - pillow==9.5.0
      - pkgutil-resolve-name==1.3.10
      - platformdirs==4.0.0
      - pluggy==1.2.0
      - prometheus-client==0.17.1
      - prompt-toolkit==3.0.48
      - psutil==7.0.0
      - ptyprocess==0.7.0
      - pycodestyle==2.9.1
      - pycparser==2.21
      - pyflakes==2.5.0
      - pygments==2.17.2
      - pyparsing==3.1.4
      - pyrsistent==0.19.3
      - pytest==7.4.4
      - python-dateutil==2.9.0.post0
      - python-json-logger==3.0.1
      - pytz==2025.2
      - pyyaml==6.0.1
      - pyzmq==26.2.1
      - requests==2.31.0
      - rfc3339-validator==0.1.4
      - rfc3986-validator==0.1.1
      - scikit-fem==8.1.0
      - scipy==1.7.3
      - send2trash==1.8.3
      - six==1.17.0
      - sniffio==1.3.1
      - snowballstemmer==2.2.0
      - soupsieve==2.4.1
      - sphinx==4.3.2
      - sphinxcontrib-applehelp==1.0.2
      - sphinxcontrib-devhelp==1.0.2
      - sphinxcontrib-htmlhelp==2.0.0
      - sphinxcontrib-jsmath==1.0.1
      - sphinxcontrib-qthelp==1.0.3
      - sphinxcontrib-serializinghtml==1.1.5
      - terminado==0.17.1
      - tinycss2==1.2.1
      - tomli==2.0.1
      - tornado==6.2
      - traitlets==5.9.0
      - typed-ast==1.5.5
      - typing-extensions==4.7.1
      - uri-template==1.3.0
      - urllib3==2.0.7
      - wcwidth==0.2.13
      - webcolors==1.13
      - webencodings==0.5.1
      - websocket-client==1.6.1
      - widgetsnbextension==4.0.13
      - y-py==0.6.2
      - ypy-websocket==0.8.4
      - zipp==3.15.0
prefix: /opt/conda/envs/PyBaMM

tests/unit/test_models/test_submodels/test_current_collector/test_effective_current_collector.py::TestEffectiveResistance2D::test_default_solver
tests/unit/test_models/test_submodels/test_current_collector/test_effective_current_collector.py::TestEffectiveResistance2D::test_get_processed_potentials
tests/unit/test_models/test_submodels/test_current_collector/test_effective_current_collector.py::TestEffectiveResistance2D::test_default_geometry tests/unit/test_models/test_submodels/test_current_collector/test_effective_current_collector.py::TestEffectiveResistance2D::test_well_posed
pybamm/models/full_battery_models/lead_acid/base_lead_acid_model.py pybamm/models/base_model.py CHANGELOG.md pybamm/models/submodels/current_collector/effective_resistance_current_collector.py
pybamm/models/full_battery_models/lead_acid/base_lead_acid_model.py pybamm/models/base_model.py CHANGELOG.md pybamm/models/submodels/current_collector/effective_resistance_current_collector.py