The Distribution Function of Differential Capacity as a new tool for analyzing the capacitive properties of Lithium-Ion batteries

Due to the toxic and flammable problems of organic electrolytes, the study on concentrated aqueous system for lithium-ion batteries (LIBs) has attracted wide attention. In this paper, by molecular dynamics simulations, the CH3COOLi aqueous system is considered as the potential concentrated aqueous system for LIBs, and all the variations of the microstructure of the aqueous system from dilution to concentration are analyzed. The details of microstructure are discussed, especially the interactions concerning anions. Among them, the first peak of RDF (radial distribution function) between the Li[Formula: see text] ion and the oxygen atom in CH3COOLi is 2.9[Formula: see text]Å, which does not change from dilution to concentration. This RDF information further indicates that when the concentration increases, the microstructures of small components formed by any two clusters do not change much, but at the same time, the spatial structures constructed by many small components are gradually built up from a broader perspective.

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Влияние диффузионных барьеров на емкостные свойства композитных анодов состава Si-CuSi-Cu

Письма в журнал технической физики ◽

10.21883/pjtf.2020.19.50034.18389 ◽

2020 ◽

Vol 46 (19) ◽

pp. 3

Author(s):

Э.Ю. Бучин ◽

А.А. Мироненко ◽

В.В. Наумов ◽

А.С. Рудый

Keyword(s):

Lithium Ion Batteries ◽

Network Structure ◽

Effective Diffusion ◽

Lithium Ion ◽

Diffusion Barriers ◽

Liquid Lithium ◽

Lithium Ions ◽

Initial Stage ◽

Capacitive Properties ◽

Anode Films

As an anode material for liquid lithium-ion batteries, film structures consisting of several identical modules [Co(x)/a-Si(100)/Cu(70)], where the value of x varied from 2 to 10 nm, have been studied. It is shown that relatively thick cobalt layers are effective diffusion barriers for silicon and copper atoms, as well as lithium ions. This leads to a decrease in the capacitive properties of the studied films. Thin cobalt layers (less than 3 nm) with a network structure, on the contrary, contribute to an increase in the capacitive properties of anode films. This is due to a more uniform distribution in their volume of drift channels of lithium ions, which are formed at the initial stage of electrode cycling.

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Pair Distribution Function Analysis and Solid State NMR Studies of Silicon Electrodes for Lithium Ion Batteries: Understanding the (De)lithiation Mechanisms

Journal of the American Chemical Society ◽

10.1021/ja108085d ◽

2011 ◽

Vol 133 (3) ◽

pp. 503-512 ◽

Cited By ~ 253

Author(s):

Baris Key ◽

Mathieu Morcrette ◽

Jean-Marie Tarascon ◽

Clare P. Grey

Keyword(s):

Distribution Function ◽

Solid State ◽

Lithium Ion Batteries ◽

Solid State Nmr ◽

Pair Distribution Function ◽

Function Analysis ◽

Lithium Ion ◽

Nmr Studies

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Determination of the Differential Capacity of Lithium-Ion Batteries by the Deconvolution of Electrochemical Impedance Spectra

Energies ◽

10.3390/en13040915 ◽

2020 ◽

Vol 13 (4) ◽

pp. 915

Author(s):

Dongxu Guo ◽

Geng Yang ◽

Guangjin Zhao ◽

Mengchao Yi ◽

Xuning Feng ◽

...

Keyword(s):

Lithium Ion Batteries ◽

Diffusion Processes ◽

Electrochemical Impedance ◽

Estimation Method ◽

Lithium Ion ◽

Joint Estimation ◽

Frequency Resolution ◽

Differential Capacity ◽

Model Free ◽

Incremental Capacity

Electrochemical impedance spectroscopy (EIS) is a powerful tool for investigating electrochemical systems, such as lithium-ion batteries or fuel cells, given its high frequency resolution. The distribution of relaxation times (DRT) method offers a model-free approach for a deeper understanding of EIS data. However, in lithium-ion batteries, the differential capacity caused by diffusion processes is non-negligible and cannot be decomposed by the DRT method, which limits the applicability of the DRT method to lithium-ion batteries. In this study, a joint estimation method with Tikhonov regularization is proposed to estimate the differential capacity and the DRT simultaneously. Moreover, the equivalence of the differential capacity and the incremental capacity is proven. Different types of commercial lithium-ion batteries are tested to validate the joint estimation method and to verify the equivalence. The differential capacity is shown to be a promising approach to the evaluation of the state-of-health (SOH) of lithium-ion batteries based on its equivalence with the incremental capacity.

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