Python Battery Mathematical Modelling (PyBaMM)

Features

• create_from_bpx/create_from_bpx_obj now apply a BPX State Initial state-of-charge via set_initial_state (supporting blended electrodes and validated to lie in [0, 1]) instead of ignoring it. (#5616)
• The parameter "Contact resistance [Ohm]" can now be a function of the volume-averaged cell temperature (in addition to a constant), and works with all thermal options. The accompanying documentation now clarifies that this represents a lumped series resistance rather than a true contact resistance (BPX#130); the name is retained to avoid a breaking change. (#5604)

Bug fixes

• Fixed BPX import leaving interpolated-table OCP hysteresis branches (OCP (lithiation) [V], OCP (delithiation) [V]) as raw data tuples instead of usable expression-tree objects. Remaining FloatFunctionTable placeholders are now converted generically, so new BPX table parameters no longer need a hand-maintained conversion list. (#5610)
• RegulariseSqrtAndPower no longer regularises state-independent bases, fixing corrupted small rate constants in exchange-current density functions. (#5600)
• Fixed Serialise.load_custom_model leaving a loaded lithium-ion model's cached param built from default options instead of the restored ones, so a model loaded with non-default options (e.g. composite "particle phases") had parameters inconsistent with its options. (#5599)
• Fixed BatteryModelOptions letting two invalid MSMR option sets pass validation and then crash during parameter construction with invalid literal for int() with base 10: 'none'; both now raise a clear OptionError. The all-or-nothing MSMR check now detects MSMR inside a per-electrode tuple (e.g. "open-circuit potential": ("MSMR", "single")), and an MSMR model must set "number of MSMR reactions" to a positive integer rather than the default "none". (#5599)
• Fixed Serialise.serialise_custom_model not recording a custom model's discretisation recipe (geometry, var_pts, submesh_types, spatial_methods), so a custom model reloaded via the BaseModel fallback (when its defining package is unavailable) was no longer discretisable. (#5609)