Battery simulation blocks for PathSim

Documentation • PathSim Homepage • GitHub

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PathSim-Batt extends the PathSim simulation framework with battery cell blocks backed by PyBaMM. All blocks follow the standard PathSim interface and can be wired into any simulation diagram.

Install

pip install pathsim-batt

Quick start

import pybamm
from pathsim import Connection, Simulation
from pathsim.blocks import Constant
from pathsim.solvers import ESDIRK43
from pathsim_batt import CellElectrothermal

cell = CellElectrothermal(initial_soc=1.0)   # defaults: SPMe + Chen2020
I_src = Constant(5.0)                         # 5 A discharge
T_src = Constant(298.15)                      # 25 °C ambient

sim = Simulation(
    blocks=[I_src, T_src, cell],
    connections=[Connection(I_src, cell["I"]), Connection(T_src, cell["T_amb"])],
    dt=1.0,
    Solver=ESDIRK43,
)
sim.run(3600)
print(f"V = {cell.outputs[0]:.3f} V  T = {cell.outputs[1]:.1f} K  SOC = {cell.outputs[3]:.3f}")

Choosing a block

Two decisions determine the right block: thermal ownership and integration strategy.

Block	Thermal	Strategy	Use when
CellElectrothermal	PyBaMM (internal)	Monolithic ODE	Single cell, coupled electro-thermal, ODE model
CellElectrical + LumpedThermal	PathSim (external)	Monolithic ODE	Pack-level, custom cooling, ODE model
CellCoSimElectrothermal	PyBaMM (internal)	Co-simulation	DAE models (DFN, lead_acid.Full), mixed solvers
CellCoSimElectrical + LumpedThermal	PathSim (external)	Co-simulation	DAE models with external thermal network

LumpedThermal is a single-node thermal block (mass, Cp, UA, T0) that receives Q_dot from a CellElectrical block and feeds back cell temperature.

PyBaMM model compatibility

Thermal sub-model and heat-source options are injected automatically — pass the bare model class with no options=.

PyBaMM model	Default parameter set	CellElectrical	CellElectrothermal	CellCoSimElectrical	CellCoSimElectrothermal
lithium_ion.SPM	Chen2020	✅	✅	✅	✅
lithium_ion.SPMe	Chen2020	✅	✅	✅	✅
lithium_ion.DFN	Chen2020	❌ DAE	❌ DAE	✅	✅
lead_acid.LOQS	Sulzer2019	✅	✅	✅ ¹	✅ ¹
lead_acid.Full	Sulzer2019	❌ DAE	❌ DAE	✅	✅
equivalent_circuit.Thevenin	ECM_Example	✅	✅	✅ ²	✅ ²

¹ Pass pybamm_solver=pybamm.CasadiSolver(mode="safe") — the default IDAKLUSolver requires a Jacobian that ODE models do not provide.

² initial_soc=1.0 fails because PyBaMM requires event values to be strictly positive at t=0; the "Maximum SoC" event is zero exactly at full charge. Any value below 1.0 (e.g. initial_soc=0.99) works.

import pybamm
from pathsim_batt import CellElectrothermal, CellCoSimElectrical

# Custom chemistry / parameter set
cell = CellElectrothermal(
    model=pybamm.lithium_ion.SPMe(),
    parameter_values=pybamm.ParameterValues("Mohtat2020"),
)

# Lead-acid via co-simulation (DAE model)
cell = CellCoSimElectrical(
    model=pybamm.lead_acid.Full(),
    parameter_values=pybamm.ParameterValues("Sulzer2019"),
    dt=1.0,
)

# Equivalent circuit model
cell = CellElectrical(
    model=pybamm.equivalent_circuit.Thevenin(),
    parameter_values=pybamm.ParameterValues("ECM_Example"),
    initial_soc=0.9,
)

License

MIT