Creating own library for a lithium ion cell

[mlnsai]

Hi Team,

I can see inbuilt cell libraries such as LGM50 (Chen2020), Enertech Cell (Ai2020) etc.

Can i create such library for a cell of my choice? (Let's say i have the manufacturing facility and i can measure/find out any parameter)

So, if i want to create a similar library for a new battery and run simulations on that. What all parameters do i require apart from "parameters" in "input" folder?

I have gone through all the parameters the code takes from "cell", "electrolyte", "positive electrode", "negative electrode", "sei", "separator", "lithium plating".

Apart from these do i require any additional parameters to make my own library of a cell?

Is it possible at all?

Thanks in advance.

[brosaplanella]

We recently reformatted the parameter structure, so this solution applies to PyBaMM 22.10 onwards. You can define your parameters directly as a dictionary, as shown in this notebook (section Using pre-defined models in PyBaMM). Note that you can also define them as a separate file (following one of the examples here) and then import them in your main script.

[PaulKranefeld]

Thank you for your help. I have not installed the package before and did that now. That worked when i executed pip install . in the cell_parameters directory but not in the working_directory (error here was: ERROR: Directory '.' is not installable. Neither 'setup.py' nor 'pyproject.toml' found.. When i run the pybamm_simulation.py now i get the following error: cannot import name 'parameters_test' from 'cell_parameters'

Edit: Is it possible that i did a mistake within the structure of the package? Do I have to place the setup.py file in the working directory and outside of the package?

[PaulKranefeld]

I now succesfully installed the package cell_parameters with parameters_test in it and it appears in site_packages within my virtual environement. Pybamm still does not recognize it if i do this:

import pybamm
import cell_parameters

model = pybamm.lithium_ion.DFN(options, name="Test", build=False)
params = pybamm.ParameterValues("parameters_test")

FileNotFoundError: Could not find parameter parameters_test.
Can someone help me?

[awadell1]

It should be pybamm_parameter_set, not pybamm_parameter_sets

from setuptools import setup

setup(
    # ...,
    entry_points = {
        "pybamm_parameter_set": [
            "parameters_test = cell_parameters.parameters_test:get_parameter_values"
        ]
    }
)

🤦‍♂️ Apologies for the issue, fixing the docs now

[PaulKranefeld]

Now it works like a charm! Thank you for your help.

[alexisfortini]

Hello, I was wondering if I could get some help with adding a parameter set. I have reviewed the documentation and this post but I am still having trouble.

These are the steps I took:

1. Set up a package in my current working directory (where parameters_test.py is a copy of Chen2020.py)

working_directory
  ├──pybamm_simulation.py   
  └──cell_parameters
       ├── setup.py  
       └── src
            └── cell_parameters
                 └── parameters_test.py

2. Added content to setup.py file to create the entry point

from setuptools import setup

setup(
    # ...,
    entry_points = {
        "pybamm_parameter_set": [
            "parameters_test = cell_parameters.parameters_test:get_parameter_values"
        ]
    }
)

3. Ran pip install -e . from working_directory/cell_parameters. Now I can see a new folder cell_parameters.egg-info has been created in working_directory/src

4. Ran the pybamm_simulation.py simulation file. Line 2 successfully added the __pycache__ folder to working_directory/src/cell_parameters, but I get FileNotFoundError: Could not find parameter parameters_test. If you have a developer install, try re-installing pybamm (e.g. `pip install -e .`) to expose recently-added parameter entry points. from line 5

import pybamm
from cell_parameters.src.cell_parameters import parameters_test

model = pybamm.lithium_ion.DFN(options, name="test", build=False)
params = pybamm.ParameterValues("parameters_test")

Where did I make a mistake? Thanks in advance for your help!

[valentinsulzer]

Try "pybamm_parameter_sets" as the entry point instead of "pybamm_parameter_set"

[alexisfortini]

Thanks for your quick response. I was able to successfully add my own parameter set with a few changes to my code. Here are the steps I took in case anyone else needs help:

1. Set up a package in my current working directory (where parameters_test.py is a copy of Chen2020.py)

working_directory
  ├──pybamm_simulation.py
  ├──setup.py   
  └──cell_parameters
       └── parameters_test.py

2. Added content to setup.py file to create the entry point

from setuptools import setup

setup(
    # ...,
    entry_points = {
        "pybamm_parameter_sets": [
            "parameters_test = cell_parameters.parameters_test:get_parameter_values"
        ]
    }
)

3. Ran pip install -e . from working_directory. Now I can see a new folder cell_parameters.egg-info has been created in working_directory

4. Ran the pybamm_simulation.py simulation file. Now I can see a new folder __pycache__ has been created in working_directory/cell_parameters, parameters_test is now included in pybamm.parameter_sets, and the model runs successfully.

import pybamm
from cell_parameters import parameters_test

print(list(pybamm.parameter_sets))

model = pybamm.lithium_ion.DFN()
chemistry = pybamm.parameter_sets.parameters_test
params = pybamm.ParameterValues(chemistry)
sim = pybamm.Simulation(model)
sim.solve([0, 3600])
sim.plot()

Thank you again for your help Dr. Sulzer!

[mlnsai]

Hey @alexisfortini and @valentinsulzer , I am trying to follow your steps but I am unable to find any setup.py file to add my own entry point. Can you help me in adding my own parameter set? Here are the steps i followed.

1. Copied the "Chen2020.py" file contents to "Test.py" within the "\pybamm\input\parameters\lithium_ion" directory within my system.
2. Updated "all = ['Ai2020', 'Chen2020', 'Chen2020_composite', 'Ecker2015',
   'Ecker2015_graphite_halfcell', 'MSMR_example_set', 'Marquis2019',
   'Mohtat2020', 'NCA_Kim2011', 'OKane2022',
   'OKane2022_graphite_SiOx_halfcell', 'ORegan2022', 'Prada2013',
   'Ramadass2004', 'Test', 'Xu2019']
   " code in init.py file within "\pybamm\input\parameters\lithium_ion" same path.
3. Ran sample code to get the error " raise ValueError(
   ValueError: 'Test' is not a valid parameter set. Parameter set must be one of:
   Ai2020
   Chayambuka2022
   Chen2020
   Chen2020_composite
   ECM_Example
   Ecker2015
   Ecker2015_graphite_halfcell
   MSMR_Example
   Marquis2019
   Mohtat2020
   NCA_Kim2011
   OKane2022
   OKane2022_graphite_SiOx_halfcell
   ORegan2022
   Prada2013
   Ramadass2004
   Sulzer2019
   Xu2019"

Can you please help me in adding the Test.py parameter set? I am using 25.1.1 version of Pybamm. Thanks in advance

@valentinsulzer @alexisfortini