1C/1C showing higher cycle life than 0.5C/0.5C

[sths008]

I am running 1C/1C charge-discharge and 0.5C/0.5C using various lithium ion models. All models are showing 1C/1C with higher cycling life than 0.5C/0.5C. Here is an example of what I am doing.

import pybamm as pb
param = pb.ParameterValues("OKane2022")

model = pb.lithium_ion.DFN(
{
"SEI": "ec reaction limited",
"SEI film resistance": "distributed",
"SEI porosity change": "true",
"lithium plating": "irreversible",
"lithium plating porosity change": "true",
}
)

experiment = pb.Experiment(
[
(
"Discharge at 1 C until 2.85 V",
"Rest for 5 minutes",
"Charge at 1 C until 4.15 V",
"Hold at 4.15 V until C/10",
"Rest for 5 minutes",

    )
]
* 500,termination = "90% capacity"

)

solver = pb.CasadiSolver(
mode="safe",
dt_max=0.01,
max_step_decrease_count=15,
rtol=1e-6,
atol=1e-6,
extra_options_setup={"max_num_steps": 10000, "print_stats": False},
perturb_algebraic_initial_conditions=True,
)

sim = pb.Simulation(model, experiment=experiment, parameter_values=param, solver=solver)
sim.solve()

I have uninstalled pybamm and reinstalled it but I am still getting this wrong results. I am using version 24.1.

I would appreciate if someone could help me with this issue.

[valentinsulzer]

Depending on the SEI model you use calendar aging may be dominating in which case higher C-rate means less time per cycle. It looks like slower degradation when plotted vs cycle number but is faster (or the same) when plotted vs time. See #3220

Additionally, temperature plays an important role, so try with the thermal model activated. Higher C-rate means higher temperature so faster SEI growth.