v24.9.0

Features

• Added additional user-configurable options to the (IDAKLUSolver) and adjusted the default values to improve performance. (#4282)
• Added the diffusion element to be used in the Thevenin model. (#4254)

Optimizations

• Update IDAKLU tests and benchmarks to use adaptive time stepping. (#4390)
• Improved adaptive time-stepping performance of the (IDAKLUSolver). (#4351)
• Improved performance and reliability of DAE consistent initialization. (#4301)
• Replaced rounded Faraday constant with its exact value in bpx.py for better comparison between different tools. (#4290)

Bug Fixes

• Fixed memory issue that caused failure when output variables were specified with (IDAKLUSolver). (#4379)
• Fixed bug where IDAKLU solver failed when output variables were specified and an event triggered. (#4300)

Breaking changes

• Replaced have_jax with has_jax, have_idaklu with has_idaklu, and
  have_iree with has_iree (#4398)
• Remove deprecated function pybamm_install_jax (#4362)
• Removed legacy python-IDAKLU solver. (#4326)

v24.5

Features

• Added new parameters "f{pref]Initial inner SEI on cracks thickness [m]" and "f{pref]Initial outer SEI on cracks thickness [m]", instead of hardcoding these to L_inner_0 / 10000 and L_outer_0 / 10000. (#4168)
• Added pybamm.DataLoader class to fetch data files from pybamm-data and store it under local cache. (#4098)
• Added time as an option for Experiment.termination. Now allows solving up to a user-specified time while also allowing different cycles and steps in an experiment to be handled normally. (#4073)
• Added plot_thermal_components to plot the contributions to the total heat generation in a battery (#4021)
• Added functions for normal probability density function (pybamm.normal_pdf) and cumulative distribution function (pybamm.normal_cdf) (#3999)
• "Basic" models are now compatible with experiments (#3995)
• Updates multiprocess Pool in BaseSolver.solve() to be constructed with context fork. Adds small example for multiprocess inputs. (#3974)
• Lithium plating now works on composite electrodes (#3919)
• Added lithium plating parameters to Ecker2015 and Ecker2015_graphite_halfcell parameter sets (#3919)
• Added custom experiment steps (#3835)
• MSMR open-circuit voltage model now depends on the temperature (#3832)
• Added support for macOS arm64 (M-series) platforms. (#3789)
• Added the ability to specify a custom solver tolerance in get_initial_stoichiometries and related functions (#3714)
• Modified step function to take an array of time t_eval as an argument and deprecated use of npts. (#3627)
• Renamed "electrode diffusivity" to "particle diffusivity" as a non-breaking change with a deprecation warning (#3624)
• Add support for BPX version 0.4.0 which allows for blended electrodes and user-defined parameters in BPX(#3414)
• Added by_submodel feature in print_parameter_info method to allow users to print parameters and types of submodels in a tabular and readable format (#3628)
• Added WyciskOpenCircuitPotential for differential capacity hysteresis state open-circuit potential submodel (#3593)
• Transport efficiency submodel has new options from the literature relating to different tortuosity factor models and also a new option called "tortuosity factor" for specifying the value or function directly as parameters (#3437)
• Heat of mixing source term can now be included into thermal models (#2837)
• Added a JAX interface to the IDAKLU solver (#3658)

Bug Fixes

• Fixed bug where passing deprecated electrode diffusivity parameter resulted in a breaking change and/or the corresponding diffusivity parameter not updating. Improved the deprecated translation around BPX. (#4176)
• Fixed a bug where a factor of electrode surface area to volume ratio is missing in the rhs of the LeadingOrderDifferential conductivity model (#4139)
• Fixes the breaking changes caused by #3624, specifically enables the deprecated parameter electrode diffusivity to be used by ParameterValues.update({name:value}) and Solver.solve(inputs={name:value}). Fixes parameter translation from old name to new name, with corrected tests. (#4072
• Set the remove_independent_variables_from_rhs to False by default, and moved the option from Discretisation.process_model to Discretisation.__init__. This fixes a bug related to the discharge capacity, but may make the simulation slower in some cases. To set the option to True, use Simulation(..., discretisation_kwargs={"remove_independent_variables_from_rhs": True}). (#4020)
• Fixed a bug where independent variables were removed from models even if they appeared in events (#4019)
• Fix bug with upwind and downwind schemes producing the wrong discretised system (#3979)
• Allow evaluation of an Interpolant object with a number (#3932)
• Added scale to dead lithium variable (#3919)
• plot_voltage_components now works even if the time does not start at 0 (#3915)
• Fixed bug where separator porosity was used in calculation instead of transport efficiency (#3905)
• Initial voltage can now match upper or lower cut-offs exactly (#3842)
• Fixed a bug where 1+1D and 2+1D models would not work with voltage or power controlled experiments(#3829)
• Update IDAKLU solver to fail gracefully when a variable is requested that was not in the solves output_variables list (#3803)
• Updated _steps_util.py to throw a specific exception when drive cycle starts at t>0 (#3756)
• Updated plot_voltage_components.py to support both Simulation and Solution objects. Added new methods in both Simulation and Solution classes for allow the syntax simulation.plot_voltage_components and solution.plot_voltage_components. Updated test_plot_voltage_components.py to reflect these changes (#3723).
• The SEI thickness decreased at some intervals when the 'electron-migration limited' model was used. It has been corrected (#3622)
• Allow input parameters in ESOH model (#3921)
• Use casadi MX.interpn_linear function instead of plugin to fix casadi_interpolant_linear.dll not found on Windows (#4077)

Optimizations

• Sped up initialization of a ProcessedVariable by making the internal xarray.DataArray initialization lazy (only gets created if interpolation is needed) (#3862)

Breaking changes

• Functions that are created using pybamm.Function(function_object, children) can no longer be differentiated symbolically (e.g. to compute the Jacobian). This should affect no users, since function derivatives for all "standard" functions are explicitly implemented (#4196)
• Removed data files under pybamm/input and released them in a separate repository upstream at pybamm-data. Note that data files under pybamm/input/parameters have not been removed. (#4098)
• Removed check_model argument from Simulation.solve. To change the check_model option, use Simulation(..., discretisation_kwargs={"check_model": False}). (#4020)
• Removed multiple Docker images. Here on, a single Docker image tagged pybamm/pybamm:latest will be provided with both solvers (IDAKLU and JAX) pre-installed. (#3992)
• Removed support for Python 3.8 (#3961)
• Renamed "ocp_soc_0_dimensional" to "ocp_soc_0" and "ocp_soc_100_dimensional" to "ocp_soc_100" (#3942)
• The ODES solver was removed due to compatibility issues. Users should use IDAKLU, Casadi, or JAX instead. (#3932)
• Integrated the [pandas] extra into the core PyBaMM package, deprecating the pybamm[pandas] optional dependency. Pandas is now a required dependency and will be installed upon installing PyBaMM (#3892)
• Renamed "have_optional_dependency" to "import_optional_dependency" (#3866)
• Integrated the [latexify] extra into the core PyBaMM package, deprecating the pybamm[latexify] set of optional dependencies. SymPy is now a required dependency and will be installed upon installing PyBaMM (#3848)
• Renamed "testing" argument for plots to "show_plot" and flipped its meaning (show_plot=True is now the default and shows the plot) (#3842)
• Dropped support for BPX version 0.3.0 and below (#3414)
• The function get_spatial_var in `pybamm.Qui...

v24.5rc2

Features

• Added new parameters "f{pref]Initial inner SEI on cracks thickness [m]" and "f{pref]Initial outer SEI on cracks thickness [m]", instead of hardcoding these to L_inner_0 / 10000 and L_outer_0 / 10000. (#4168)
• Added pybamm.DataLoader class to fetch data files from pybamm-data and store it under local cache. (#4098)
• Added time as an option for Experiment.termination. Now allows solving up to a user-specified time while also allowing different cycles and steps in an experiment to be handled normally. (#4073)
• Added plot_thermal_components to plot the contributions to the total heat generation in a battery (#4021)
• Added functions for normal probability density function (pybamm.normal_pdf) and cumulative distribution function (pybamm.normal_cdf) (#3999)
• "Basic" models are now compatible with experiments (#3995)
• Updates multiprocess Pool in BaseSolver.solve() to be constructed with context fork. Adds small example for multiprocess inputs. (#3974)
• Lithium plating now works on composite electrodes (#3919)
• Added lithium plating parameters to Ecker2015 and Ecker2015_graphite_halfcell parameter sets (#3919)
• Added custom experiment steps (#3835)
• MSMR open-circuit voltage model now depends on the temperature (#3832)
• Added support for macOS arm64 (M-series) platforms. (#3789)
• Added the ability to specify a custom solver tolerance in get_initial_stoichiometries and related functions (#3714)
• Modified step function to take an array of time t_eval as an argument and deprecated use of npts. (#3627)
• Renamed "electrode diffusivity" to "particle diffusivity" as a non-breaking change with a deprecation warning (#3624)
• Add support for BPX version 0.4.0 which allows for blended electrodes and user-defined parameters in BPX(#3414)
• Added by_submodel feature in print_parameter_info method to allow users to print parameters and types of submodels in a tabular and readable format (#3628)
• Added WyciskOpenCircuitPotential for differential capacity hysteresis state open-circuit potential submodel (#3593)
• Transport efficiency submodel has new options from the literature relating to different tortuosity factor models and also a new option called "tortuosity factor" for specifying the value or function directly as parameters (#3437)
• Heat of mixing source term can now be included into thermal models (#2837)

Bug Fixes

• Fixed bug where passing deprecated electrode diffusivity parameter resulted in a breaking change and/or the corresponding diffusivity parameter not updating. Improved the deprecated translation around BPX. (#4176)
• Fixed a bug where a factor of electrode surface area to volume ratio is missing in the rhs of the LeadingOrderDifferential conductivity model (#4139)
• Fixes the breaking changes caused by #3624, specifically enables the deprecated parameter electrode diffusivity to be used by ParameterValues.update({name:value}) and Solver.solve(inputs={name:value}). Fixes parameter translation from old name to new name, with corrected tests. (#4072
• Set the remove_independent_variables_from_rhs to False by default, and moved the option from Discretisation.process_model to Discretisation.__init__. This fixes a bug related to the discharge capacity, but may make the simulation slower in some cases. To set the option to True, use Simulation(..., discretisation_kwargs={"remove_independent_variables_from_rhs": True}). (#4020)
• Fixed a bug where independent variables were removed from models even if they appeared in events (#4019)
• Fix bug with upwind and downwind schemes producing the wrong discretised system (#3979)
• Allow evaluation of an Interpolant object with a number (#3932)
• Added scale to dead lithium variable (#3919)
• plot_voltage_components now works even if the time does not start at 0 (#3915)
• Fixed bug where separator porosity was used in calculation instead of transport efficiency (#3905)
• Initial voltage can now match upper or lower cut-offs exactly (#3842)
• Fixed a bug where 1+1D and 2+1D models would not work with voltage or power controlled experiments(#3829)
• Update IDAKLU solver to fail gracefully when a variable is requested that was not in the solves output_variables list (#3803)
• Updated _steps_util.py to throw a specific exception when drive cycle starts at t>0 (#3756)
• Updated plot_voltage_components.py to support both Simulation and Solution objects. Added new methods in both Simulation and Solution classes for allow the syntax simulation.plot_voltage_components and solution.plot_voltage_components. Updated test_plot_voltage_components.py to reflect these changes (#3723).
• The SEI thickness decreased at some intervals when the 'electron-migration limited' model was used. It has been corrected (#3622)
• Allow input parameters in ESOH model (#3921)
• Use casadi MX.interpn_linear function instead of plugin to fix casadi_interpolant_linear.dll not found on Windows (#4077)

Optimizations

• Sped up initialization of a ProcessedVariable by making the internal xarray.DataArray initialization lazy (only gets created if interpolation is needed) (#3862)

Breaking changes

• Functions that are created using pybamm.Function(function_object, children) can no longer be differentiated symbolically (e.g. to compute the Jacobian). This should affect no users, since function derivatives for all "standard" functions are explicitly implemented (#4196)
• Removed data files under pybamm/input and released them in a separate repository upstream at pybamm-data. Note that data files under pybamm/input/parameters have not been removed. (#4098)
• Removed check_model argument from Simulation.solve. To change the check_model option, use Simulation(..., discretisation_kwargs={"check_model": False}). (#4020)
• Removed multiple Docker images. Here on, a single Docker image tagged pybamm/pybamm:latest will be provided with both solvers (IDAKLU and JAX) pre-installed. (#3992)
• Removed support for Python 3.8 (#3961)
• Renamed "ocp_soc_0_dimensional" to "ocp_soc_0" and "ocp_soc_100_dimensional" to "ocp_soc_100" (#3942)
• The ODES solver was removed due to compatibility issues. Users should use IDAKLU, Casadi, or JAX instead. (#3932)
• Integrated the [pandas] extra into the core PyBaMM package, deprecating the pybamm[pandas] optional dependency. Pandas is now a required dependency and will be installed upon installing PyBaMM (#3892)
• Renamed "have_optional_dependency" to "import_optional_dependency" (#3866)
• Integrated the [latexify] extra into the core PyBaMM package, deprecating the pybamm[latexify] set of optional dependencies. SymPy is now a required dependency and will be installed upon installing PyBaMM (#3848)
• Renamed "testing" argument for plots to "show_plot" and flipped its meaning (show_plot=True is now the default and shows the plot) (#3842)
• Dropped support for BPX version 0.3.0 and below (#3414)

v24.5rc1

Features

• Added functionality to pass in arbitrary functions of time as the argument for a (pybamm.step). (#4222)
• Added new parameters "f{pref]Initial inner SEI on cracks thickness [m]" and "f{pref]Initial outer SEI on cracks thickness [m]", instead of hardcoding these to L_inner_0 / 10000 and L_outer_0 / 10000. (#4168)
• Added pybamm.DataLoader class to fetch data files from pybamm-data and store it under local cache. (#4098)
• Added time as an option for Experiment.termination. Now allows solving up to a user-specified time while also allowing different cycles and steps in an experiment to be handled normally. (#4073)
• Added plot_thermal_components to plot the contributions to the total heat generation in a battery (#4021)
• Added functions for normal probability density function (pybamm.normal_pdf) and cumulative distribution function (pybamm.normal_cdf) (#3999)
• "Basic" models are now compatible with experiments (#3995)
• Updates multiprocess Pool in BaseSolver.solve() to be constructed with context fork. Adds small example for multiprocess inputs. (#3974)
• Lithium plating now works on composite electrodes (#3919)
• Added lithium plating parameters to Ecker2015 and Ecker2015_graphite_halfcell parameter sets (#3919)
• Added custom experiment steps (#3835)
• MSMR open-circuit voltage model now depends on the temperature (#3832)
• Added support for macOS arm64 (M-series) platforms. (#3789)
• Added the ability to specify a custom solver tolerance in get_initial_stoichiometries and related functions (#3714)
• Modified step function to take an array of time t_eval as an argument and deprecated use of npts. (#3627)
• Renamed "electrode diffusivity" to "particle diffusivity" as a non-breaking change with a deprecation warning (#3624)
• Add support for BPX version 0.4.0 which allows for blended electrodes and user-defined parameters in BPX(#3414)
• Added by_submodel feature in print_parameter_info method to allow users to print parameters and types of submodels in a tabular and readable format (#3628)
• Added WyciskOpenCircuitPotential for differential capacity hysteresis state open-circuit potential submodel (#3593)
• Transport efficiency submodel has new options from the literature relating to different tortuosity factor models and also a new option called "tortuosity factor" for specifying the value or function directly as parameters (#3437)
• Heat of mixing source term can now be included into thermal models (#2837)

Bug Fixes

• Fixed bug where passing deprecated electrode diffusivity parameter resulted in a breaking change and/or the corresponding diffusivity parameter not updating. Improved the deprecated translation around BPX. (#4176)
• Fixed a bug where a factor of electrode surface area to volume ratio is missing in the rhs of the LeadingOrderDifferential conductivity model (#4139)
• Fixes the breaking changes caused by #3624, specifically enables the deprecated parameter electrode diffusivity to be used by ParameterValues.update({name:value}) and Solver.solve(inputs={name:value}). Fixes parameter translation from old name to new name, with corrected tests. (#4072
• Set the remove_independent_variables_from_rhs to False by default, and moved the option from Discretisation.process_model to Discretisation.__init__. This fixes a bug related to the discharge capacity, but may make the simulation slower in some cases. To set the option to True, use Simulation(..., discretisation_kwargs={"remove_independent_variables_from_rhs": True}). (#4020)
• Fixed a bug where independent variables were removed from models even if they appeared in events (#4019)
• Fix bug with upwind and downwind schemes producing the wrong discretised system (#3979)
• Allow evaluation of an Interpolant object with a number (#3932)
• Added scale to dead lithium variable (#3919)
• plot_voltage_components now works even if the time does not start at 0 (#3915)
• Fixed bug where separator porosity was used in calculation instead of transport efficiency (#3905)
• Initial voltage can now match upper or lower cut-offs exactly (#3842)
• Fixed a bug where 1+1D and 2+1D models would not work with voltage or power controlled experiments(#3829)
• Update IDAKLU solver to fail gracefully when a variable is requested that was not in the solves output_variables list (#3803)
• Updated _steps_util.py to throw a specific exception when drive cycle starts at t>0 (#3756)
• Updated plot_voltage_components.py to support both Simulation and Solution objects. Added new methods in both Simulation and Solution classes for allow the syntax simulation.plot_voltage_components and solution.plot_voltage_components. Updated test_plot_voltage_components.py to reflect these changes (#3723).
• The SEI thickness decreased at some intervals when the 'electron-migration limited' model was used. It has been corrected (#3622)
• Allow input parameters in ESOH model (#3921)
• Use casadi MX.interpn_linear function instead of plugin to fix casadi_interpolant_linear.dll not found on Windows (#4077)

Optimizations

• Sped up initialization of a ProcessedVariable by making the internal xarray.DataArray initialization lazy (only gets created if interpolation is needed) (#3862)

Breaking changes

• Functions that are created using pybamm.Function(function_object, children) can no longer be differentiated symbolically (e.g. to compute the Jacobian). This should affect no users, since function derivatives for all "standard" functions are explicitly implemented (#4196)
• Removed data files under pybamm/input and released them in a separate repository upstream at pybamm-data. Note that data files under pybamm/input/parameters have not been removed. (#4098)
• Removed check_model argument from Simulation.solve. To change the check_model option, use Simulation(..., discretisation_kwargs={"check_model": False}). (#4020)
• Removed multiple Docker images. Here on, a single Docker image tagged pybamm/pybamm:latest will be provided with both solvers (IDAKLU and JAX) pre-installed. (#3992)
• Removed support for Python 3.8 (#3961)
• Renamed "ocp_soc_0_dimensional" to "ocp_soc_0" and "ocp_soc_100_dimensional" to "ocp_soc_100" (#3942)
• The ODES solver was removed due to compatibility issues. Users should use IDAKLU, Casadi, or JAX instead. (#3932)
• Integrated the [pandas] extra into the core PyBaMM package, deprecating the pybamm[pandas] optional dependency. Pandas is now a required dependency and will be installed upon installing PyBaMM (#3892)
• Renamed "have_optional_dependency" to "import_optional_dependency" (#3866)
• Integrated the [latexify] extra into the core PyBaMM package, deprecating the pybamm[latexify] set of optional dependencies. SymPy is now a required dependency and will be installed upon installing PyBaMM (#3848)
• Renamed "testing" argument for plots to "show_plot" and flipped its meaning (show_plot=True is now the default and shows the plot) (#3842)
• Dropped support for BPX version 0.3.0 and below ([#3414](https://github.com/pybamm-team/PyBaMM/pull/...

v24.5rc0

Features

• Added new parameters "f{pref]Initial inner SEI on cracks thickness [m]" and "f{pref]Initial outer SEI on cracks thickness [m]", instead of hardcoding these to L_inner_0 / 10000 and L_outer_0 / 10000. (#4168)
• Added pybamm.DataLoader class to fetch data files from pybamm-data and store it under local cache. (#4098)
• Added time as an option for Experiment.termination. Now allows solving up to a user-specified time while also allowing different cycles and steps in an experiment to be handled normally. (#4073)
• Added plot_thermal_components to plot the contributions to the total heat generation in a battery (#4021)
• Added functions for normal probability density function (pybamm.normal_pdf) and cumulative distribution function (pybamm.normal_cdf) (#3999)
• "Basic" models are now compatible with experiments (#3995)
• Updates multiprocess Pool in BaseSolver.solve() to be constructed with context fork. Adds small example for multiprocess inputs. (#3974)
• Lithium plating now works on composite electrodes (#3919)
• Added lithium plating parameters to Ecker2015 and Ecker2015_graphite_halfcell parameter sets (#3919)
• Added custom experiment steps (#3835)
• MSMR open-circuit voltage model now depends on the temperature (#3832)
• Added support for macOS arm64 (M-series) platforms. (#3789)
• Added the ability to specify a custom solver tolerance in get_initial_stoichiometries and related functions (#3714)
• Modified step function to take an array of time t_eval as an argument and deprecated use of npts. (#3627)
• Renamed "electrode diffusivity" to "particle diffusivity" as a non-breaking change with a deprecation warning (#3624)
• Add support for BPX version 0.4.0 which allows for blended electrodes and user-defined parameters in BPX(#3414)
• Added by_submodel feature in print_parameter_info method to allow users to print parameters and types of submodels in a tabular and readable format (#3628)
• Added WyciskOpenCircuitPotential for differential capacity hysteresis state open-circuit potential submodel (#3593)
• Transport efficiency submodel has new options from the literature relating to different tortuosity factor models and also a new option called "tortuosity factor" for specifying the value or function directly as parameters (#3437)
• Heat of mixing source term can now be included into thermal models (#2837)

Bug Fixes

• Fixed bug where passing deprecated electrode diffusivity parameter resulted in a breaking change and/or the corresponding diffusivity parameter not updating. Improved the deprecated translation around BPX. (#4176)
• Fixed a bug where a factor of electrode surface area to volume ratio is missing in the rhs of the LeadingOrderDifferential conductivity model (#4139)
• Fixes the breaking changes caused by #3624, specifically enables the deprecated parameter electrode diffusivity to be used by ParameterValues.update({name:value}) and Solver.solve(inputs={name:value}). Fixes parameter translation from old name to new name, with corrected tests. (#4072
• Set the remove_independent_variables_from_rhs to False by default, and moved the option from Discretisation.process_model to Discretisation.__init__. This fixes a bug related to the discharge capacity, but may make the simulation slower in some cases. To set the option to True, use Simulation(..., discretisation_kwargs={"remove_independent_variables_from_rhs": True}). (#4020)
• Fixed a bug where independent variables were removed from models even if they appeared in events (#4019)
• Fix bug with upwind and downwind schemes producing the wrong discretised system (#3979)
• Allow evaluation of an Interpolant object with a number (#3932)
• Added scale to dead lithium variable (#3919)
• plot_voltage_components now works even if the time does not start at 0 (#3915)
• Fixed bug where separator porosity was used in calculation instead of transport efficiency (#3905)
• Initial voltage can now match upper or lower cut-offs exactly (#3842)
• Fixed a bug where 1+1D and 2+1D models would not work with voltage or power controlled experiments(#3829)
• Update IDAKLU solver to fail gracefully when a variable is requested that was not in the solves output_variables list (#3803)
• Updated _steps_util.py to throw a specific exception when drive cycle starts at t>0 (#3756)
• Updated plot_voltage_components.py to support both Simulation and Solution objects. Added new methods in both Simulation and Solution classes for allow the syntax simulation.plot_voltage_components and solution.plot_voltage_components. Updated test_plot_voltage_components.py to reflect these changes (#3723).
• The SEI thickness decreased at some intervals when the 'electron-migration limited' model was used. It has been corrected (#3622)
• Allow input parameters in ESOH model (#3921)
• Use casadi MX.interpn_linear function instead of plugin to fix casadi_interpolant_linear.dll not found on Windows (#4077)

Optimizations

• Sped up initialization of a ProcessedVariable by making the internal xarray.DataArray initialization lazy (only gets created if interpolation is needed) (#3862)

Breaking changes

• Functions that are created using pybamm.Function(function_object, children) can no longer be differentiated symbolically (e.g. to compute the Jacobian). This should affect no users, since function derivatives for all "standard" functions are explicitly implemented (#4196)
• Removed data files under pybamm/input and released them in a separate repository upstream at pybamm-data. Note that data files under pybamm/input/parameters have not been removed. (#4098)
• Removed check_model argument from Simulation.solve. To change the check_model option, use Simulation(..., discretisation_kwargs={"check_model": False}). (#4020)
• Removed multiple Docker images. Here on, a single Docker image tagged pybamm/pybamm:latest will be provided with both solvers (IDAKLU and JAX) pre-installed. (#3992)
• Removed support for Python 3.8 (#3961)
• Renamed "ocp_soc_0_dimensional" to "ocp_soc_0" and "ocp_soc_100_dimensional" to "ocp_soc_100" (#3942)
• The ODES solver was removed due to compatibility issues. Users should use IDAKLU, Casadi, or JAX instead. (#3932)
• Integrated the [pandas] extra into the core PyBaMM package, deprecating the pybamm[pandas] optional dependency. Pandas is now a required dependency and will be installed upon installing PyBaMM (#3892)
• Renamed "have_optional_dependency" to "import_optional_dependency" (#3866)
• Integrated the [latexify] extra into the core PyBaMM package, deprecating the pybamm[latexify] set of optional dependencies. SymPy is now a required dependency and will be installed upon installing PyBaMM (#3848)
• Renamed "testing" argument for plots to "show_plot" and flipped its meaning (show_plot=True is now the default and shows the plot) (#3842)
• Dropped support for BPX version 0.3.0 and below (#3414)

v24.1

Features

• The pybamm_install_odes command now includes support for macOS systems and can be used to set up SUNDIALS and install the scikits.odes solver on macOS (#3417, #3706)
• Added support for Python 3.12 (#3531)
• Added method to get QuickPlot axes by variable (#3596)
• Added custom experiment terminations (#3596)
• Mechanical parameters are now a function of stoichiometry and temperature (#3576)
• Added a new unary operator, EvaluateAt, that evaluates a spatial variable at a given position (#3573)
• Added a method, insert_reference_electrode, to pybamm.lithium_ion.BaseModel that insert a reference electrode to measure the electrolyte potential at a given position in space and adds new variables that mimic a 3E cell setup. (#3573)
• Serialisation added so models can be written to/read from JSON (#3397)
• Added a get_parameter_info method for models and modified "print_parameter_info" functionality to extract all parameters and their type in a tabular and readable format (#3584)
• Mechanical parameters are now a function of stoichiometry and temperature (#3576)

Bug fixes

• Fixed a bug that lead to a ShapeError when specifying "Ambient temperature [K]" as an Interpolant with an isothermal model (#3761)
• Fixed a bug where if the first step(s) in a cycle are skipped then the cycle solution started from the model's initial conditions instead of from the last state of the previous cycle (#3708)
• Fixed a bug where the lumped thermal model conflates cell volume with electrode volume (#3707)
• Reverted a change to the coupled degradation example notebook that caused it to be unstable for large numbers of cycles (#3691)
• Fixed a bug where simulations using the CasADi-based solvers would fail randomly with the half-cell model (#3494)
• Fixed bug that made identical Experiment steps with different end times crash (#3516)
• Fixed bug in calculation of theoretical energy that made it very slow (#3506)
• The irreversible plating model now increments f"{Domain} dead lithium concentration [mol.m-3]", not f"{Domain} lithium plating concentration [mol.m-3]" as it did previously. (#3485)

Optimizations

• Updated jax and jaxlib to the latest available versions and added Windows (Python 3.9+) support for the Jax solver (#3550)

Breaking changes

• The parameters GeometricParameters.A_cooling and GeometricParameters.V_cell are now automatically computed from the electrode heights, widths and thicknesses if the "cell geometry" option is "pouch" and from the parameters "Cell cooling surface area [m2]" and "Cell volume [m3]", respectively, otherwise. When using the lumped thermal model we recommend using the "arbitrary" cell geometry and specifying the parameters "Cell cooling surface area [m2]", "Cell volume [m3]" and "Total heat transfer coefficient [W.m-2.K-1]" directly. (#3707)
• Dropped support for the [jax] extra, i.e., the Jax solver when running on Python 3.8. The Jax solver is now available on Python 3.9 and above (#3550)

v24.1rc2

Bug fixes

• Fixed a bug that lead to a ShapeError when specifying "Ambient temperature [K]" as an Interpolant with an isothermal model (#3761)

v24.1rc1

Bug fixes

• Fixed a bug where if the first step(s) in a cycle are skipped then the cycle solution started from the model's initial conditions instead of from the last state of the previous cycle (#3708)
• Fixed a bug where the lumped thermal model conflates cell volume with electrode volume (#3707)

v24.1rc0

Features

• The pybamm_install_odes command now includes support for macOS systems and can be used to set up SUNDIALS and install the scikits.odes solver on macOS (#3417)
• Added support for Python 3.12 (#3531)
• Added method to get QuickPlot axes by variable (#3596)
• Added custom experiment terminations (#3596)
• Mechanical parameters are now a function of stoichiometry and temperature (#3576)
• Added a new unary operator, EvaluateAt, that evaluates a spatial variable at a given position (#3573)
• Added a method, insert_reference_electrode, to pybamm.lithium_ion.BaseModel that insert a reference electrode to measure the electrolyte potential at a given position in space and adds new variables that mimic a 3E cell setup. (#3573)
• Serialisation added so models can be written to/read from JSON (#3397)
• Added a get_parameter_info method for models and modified "print_parameter_info" functionality to extract all parameters and their type in a tabular and readable format (#3584)
• Mechanical parameters are now a function of stoichiometry and temperature (#3576)

Bug fixes

• Reverted a change to the coupled degradation example notebook that caused it to be unstable for large numbers of cycles (#3691)
• Fixed a bug where simulations using the CasADi-based solvers would fail randomly with the half-cell model (#3494)
• Fixed bug that made identical Experiment steps with different end times crash (#3516)
• Fixed bug in calculation of theoretical energy that made it very slow (#3506)
• The irreversible plating model now increments f"{Domain} dead lithium concentration [mol.m-3]", not f"{Domain} lithium plating concentration [mol.m-3]" as it did previously. (#3485)

Optimizations

• Updated jax and jaxlib to the latest available versions and added Windows (Python 3.9+) support for the Jax solver (#3550)

Breaking changes

• Dropped support for the [jax] extra, i.e., the Jax solver when running on Python 3.8. The Jax solver is now available on Python 3.9 and above (#3550)

v23.9

Features

• The parameter "Ambient temperature [K]" can now be given as a function of position (y,z) and time t. The "edge" and "current collector" heat transfer coefficient parameters can also depend on (y,z) (#3257)
• Spherical and cylindrical shell domains can now be solved with any boundary conditions (#3237)
• Processed variables now get the spatial variables automatically, allowing plotting of more generic models (#3234)
• Numpy functions now work with PyBaMM symbols (e.g. np.exp(pybamm.Symbol("a")) returns pybamm.Exp(pybamm.Symbol("a"))). This means that parameter functions can be specified using numpy functions instead of pybamm functions. Additionally, combining numpy arrays with pybamm objects now works (the numpy array is converted to a pybamm array) (#3205)
• Half-cell models where graphite - or other negative electrode material of choice - is treated as the positive electrode (#3198)
• Degradation mechanisms SEI, SEI on cracks and lithium plating can be made to work on the positive electrode by specifying the relevant options as a 2-tuple. If a tuple is not given and working electrode is set to both, they will be applied on the negative electrode only. (#3198)
• Added an example notebook to demonstrate how to use half-cell models (#3198)
• Added option to use an empirical hysteresis model for the diffusivity and exchange-current density (#3194)
• Double-layer capacity can now be provided as a function of temperature (#3174)
• pybamm_install_jax is deprecated. It is now replaced with pip install pybamm[jax] (#3163)
• Implement the MSMR model (#3116)
• Added new example notebook rpt-experiment to demonstrate how to set up degradation experiments with RPTs (#2851)

Bug fixes

• Fixed a bug where the JaxSolver would fails when using GPU support with no input parameters (#3423)
• Make pybamm importable with minimal dependencies (#3044, #3475)
• Fixed a bug where supplying an initial soc did not work with half cell models (#3456)
• Fixed a bug where empty lists passed to QuickPlot resulted in an IndexError and did not return a meaningful error message (#3359)
• Fixed a bug where there was a missing thermal conductivity in the thermal pouch cell models (#3330)
• Fixed a bug that caused incorrect results of “{Domain} electrode thickness change [m]” due to the absence of dimension for the variable electrode_thickness_change(#3329).
• Fixed a bug that occured in check_ys_are_not_too_large when trying to reference y-slice where the referenced variable was not a pybamm.StateVector (#3313
• Fixed a bug with _Heaviside._evaluate_for_shape which meant some expressions involving heaviside function and subtractions did not work (#3306)
• Attributes of pybamm.Simulation objects (models, parameter values, geometries, choice of solver, and output variables) are now private and as such cannot be edited in-place after the simulation has been created (#3267
• Fixed bug causing incorrect activation energies using create_from_bpx() (#3242)
• Fixed a bug where the "basic" lithium-ion models gave incorrect results when using nonlinear particle diffusivity (#3207)
• Particle size distributions now work with SPMe and NewmanTobias models (#3207)
• Attempting to set working electrode to negative now triggers an OptionError. Instead, set it to positive and use what would normally be the negative electrode as the positive electrode. (#3198)
• Fix to simulate c_rate steps with drive cycles (#3186)
• Always save last cycle in experiment, to fix issues with starting_solution and last_state (#3177)
• Fix simulations with starting_solution to work with start_time experiments (#3177)
• Fix SEI Example Notebook (#3166)
• Thevenin() model is now constructed with standard variables: Time [s], Time [min], Time [h] (#3143)
• Error generated when invalid parameter values are passed (#3132)
• Parameters in Prada2013 have been updated to better match those given in the paper, which is a 2.3 Ah cell, instead of the mix-and-match with the 1.1 Ah cell from Lain2019 (#3096)
• The OneDimensionalX thermal model has been updated to account for edge/tab cooling and account for the current collector volumetric heat capacity. It now gives the correct behaviour compared with a lumped model with the correct total heat transfer coefficient and surface area for cooling. (#3042)

Optimizations

• Improved how steps are processed in simulations to reduce memory usage (#3261)
• Added parameter list support to JAX solver, permitting multithreading / GPU execution (#3121)

Breaking changes

• The parameter "Exchange-current density for lithium plating [A.m-2]" has been renamed to "Exchange-current density for lithium metal electrode [A.m-2]" when referring to the lithium plating reaction on the surface of a lithium metal electrode (#3445)
• Dropped support for i686 (32-bit) architectures on GNU/Linux distributions (#3412)
• The class pybamm.thermal.OneDimensionalX has been moved to pybamm.thermal.pouch_cell.OneDimensionalX to reflect the fact that the model formulation implicitly assumes a pouch cell geometry (#3257)
• The "lumped" thermal option now always used the parameters "Cell cooling surface area [m2]", "Cell volume [m3]" and "Total heat transfer coefficient [W.m-2.K-1]" to compute the cell cooling regardless of the chosen "cell geometry" option. The user must now specify the correct values for these parameters instead of them being calculated based on e.g. a pouch cell. An OptionWarning is raised to let users know to update their parameters (#3257)
• Numpy functions now work with PyBaMM symbols (e.g. np.exp(pybamm.Symbol("a")) returns pybamm.Exp(pybamm.Symbol("a"))). This means that parameter functions can be specified using numpy functions instead of pybamm functions. Additionally, combining numpy arrays with pybamm objects now works (the numpy array is converted to a pybamm array) (#3205)
• The SEI, SEI on cracks and lithium plating submodels can now be used on either electrode, which means the __init__ functions for the relevant classes now have domain as a required argument (#3198)
• Likewise, the names of all variables corresponding to those submodels now have domains. For example, instead of SEI thickness [m], use Negative SEI thickness [m] or Positive SEI thickness [m]. (#3198)
• If options["working electrode"] == "both" and either SEI, SEI on cracks or lithium plating are not provided as tuples, they are automatically made into tuples. This directly modifies extra_options, not default_options to ensure the other changes to default_options still happen when required. (#3198)
• Added option to use an empirical hysteresis model for the diffusivity and exchange-current density (#3194)
• Double-layer capacity can now be provided as a function of temperature (#3174)
• pybamm_install_jax is deprecated. It is now replaced with pip install pybamm[jax] (#3163)
• PyBaMM now has optional dependencies that can be installed with the pattern pip install pybamm[option] e.g. pybamm[plot] (#3044, #3475)