TLM

[privasr]

Hi! Thanks for such a nice work with this software, I would like to suggest the incorporation of a model I'm trying to use to fit my data, the Transition Line Model, based on https://iopscience.iop.org/article/10.1149/1945-7111/ac49ce/meta, and https://doi.org/10.1016/j.jpowsour.2016.10.090

I have rewritten the TLMQ code, to adapt it to this model

`
def TLM(p, f):
"""Transmission-line model as defined in Eq. 1 of [1]

Notes
-----
.. math::

    Z = \\sqrt{\\frac{R_{d}}{Z_{S}}} \\coth \\sqrt{R_{d}Z_{S}}


[1] Julian Ascolani-Yael et al 2022 J. Electrochem. Soc
https://iopscience.iop.org/article/10.1149/1945-7111/ac49ce/meta`_.
"""
omega = 2 * np.pi * np.array(f)
Rd, Rs, Qs, gamma = p[0], p[1], p[2], p[3]
Zs = (1/Rs) + (Qs * (1j * omega) ** gamma)
Z = np.sqrt(Rd / Zs) / np.tanh(np.sqrt(Rd * Zs))
return Z`