ScipySolver

The ScipySolver wraps scipy.integrate.solve_ivp to solve ODE-only battery models. It is the simplest solver and requires no additional compiled dependencies.

pybamm.ScipySolver wraps scipy.integrate.solve_ivp and is the easiest way to get started when your model produces a pure ODE system.

ScipySolver does not support DAE (differential-algebraic) models. Most lithium-ion models (SPM, SPMe, DFN) include algebraic equations and require CasadiSolver or IDAKLUSolver.

Constructor

pybamm.ScipySolver(
    method="BDF",
    rtol=1e-6,
    atol=1e-6,
    extrap_tol=None,
    on_extrapolation=None,
    extra_options=None,
)

method · str · default: "\"BDF\""

Integration method passed to solve_ivp. Supported values:

Method	Description
"BDF"	Implicit BDF (default); good for stiff problems
"RK45"	Explicit Runge-Kutta 4(5); non-stiff problems
"RK23"	Explicit Runge-Kutta 2(3)
"DOP853"	Explicit Runge-Kutta of order 8
"Radau"	Implicit Runge-Kutta (Radau IIA); stiff
"LSODA"	Automatic stiff/non-stiff switching

rtol · float · default: "1e-6"

Relative tolerance.

atol · float · default: "1e-6"

Absolute tolerance.

extrap_tol · float | None · default: "0"

Tolerance for detecting extrapolation beyond the solved interval.

on_extrapolation · str · default: "\"warn\""

Behaviour on extrapolation: "warn", "error", or "ignore".

extra_options · dict | None · default: "{}"

Additional keyword arguments forwarded to solve_ivp (e.g. {"max_step": 10}).

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Examples

Basic ODE solve

import pybamm

# SPM with "reformulated" option produces a pure ODE
model = pybamm.lithium_ion.SPM()

param = pybamm.ParameterValues("Chen2020")
solver = pybamm.ScipySolver(method="BDF")

sim = pybamm.Simulation(model, parameter_values=param, solver=solver)
sol = sim.solve([0, 3600])
print(sol["Terminal voltage [V]"].entries[-1])

Sensitivity analysis is not supported by ScipySolver. Use IDAKLUSolver if you need parameter sensitivities.