The oxygen vacancy in Li-ion battery cathode materials

Oxygen vacancies can promote Li-ion diffusion, reduce the charge transfer resistance, and improve the capacity and rate performance of Li-ion batteries. However, oxygen vacancies can also lead to accelerated degradation of the cathode material structure, and lead to phase transition etc.

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Modelling the Impedance Response of Graded LiFePO4 Cathodes for Li-Ion Batteries

Journal of The Electrochemical Society ◽

10.1149/1945-7111/ac48c6 ◽

2022 ◽

Author(s):

Ross Drummond ◽

Chuan Cheng ◽

Patrick Grant ◽

Stephen Duncan

Keyword(s):

Electrochemical Impedance ◽

Current Collector ◽

Charge Transfer Resistance ◽

Type Model ◽

Li Ion Batteries ◽

Li Ion Battery ◽

Transfer Resistance ◽

Electrode Current ◽

Degradation Rates ◽

Li Ion

Abstract Graded electrodes for Li-ion batteries aim to exploit controlled variations in local electrode microstructure to improve overall battery performance, including reduced degradation rates and increased capacity at high discharge rates. However, the mechanisms by which grading might deliver performance benefit, and under what conditions, are not yet fully understood. A Li-ion battery electrochemical model (a modified Doyle-Fuller-Newman type model capable of generating impedance functions) is developed in which local microstructural changes are captured in order to understand why and when graded electrodes can offer performance benefits. Model predictions are evaluated against experimental electrochemical impedance data obtained from electrodes with micro-scale, controlled variations in microstructure. A region locally enriched with carbon at the electrode/current collector interface is shown to significantly reduce the overpotential distribution across the thickness of a LiFePO$_4$-based Li-ion battery cathode, resulting in a lower charge transfer resistance and impedance. The insights gained from the LiFePO$_4$-based electrodes are generalised to wider design principles for both uniform and graded Li-ion battery electrodes.

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Ti3Si0.75Al0.25C2 Nanosheets as Promising Anode Material for Li-Ion Batteries

Nanomaterials ◽

10.3390/nano11123449 ◽

2021 ◽

Vol 11 (12) ◽

pp. 3449

Author(s):

Jianguang Xu ◽

Qiang Wang ◽

Boman Li ◽

Wei Yao ◽

Meng He

Keyword(s):

Anode Materials ◽

High Capacity ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

Rate Performance ◽

Li Ion Batteries ◽

Transfer Resistance ◽

Li Ion ◽

Enhanced Electrochemical Performance ◽

Small Charge

Herein we report that novel two-dimensional (2D) Ti3Si0.75Al0.25C2 (TSAC) nanosheets, obtained by sonically exfoliating their bulk counterpart in alcohol, performs promising electrochemical activities in a reversible lithiation and delithiation procedure. The as-exfoliated 2D TSAC nanosheets show significantly enhanced lithium-ion uptake capability in comparison with their bulk counterpart, with a high capacity of ≈350 mAh g−1 at 200 mA g−1, high cycling stability and excellent rate performance (150 mAh g−1 after 200 cycles at 8000 mA g−1). The enhanced electrochemical performance of TSAC nanosheets is mainly a result of their fast Li-ion transport, large surface area and small charge transfer resistance. The discovery in this work highlights the uniqueness of a family of 2D layered MAX materials, such as Ti3GeC2, Ti3SnC2 and Ti2SC, which will likely be the promising choices as anode materials for lithium-ion batteries (LIBs).

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Layered-spinel capped nanotube assembled 3D Li-rich hierarchitectures for high performance Li-ion battery cathodes

Journal of Materials Chemistry A ◽

10.1039/c6ta05676h ◽

2016 ◽

Vol 4 (47) ◽

pp. 18416-18425 ◽

Cited By ~ 41

Author(s):

Fu-Da Yu ◽

Lan-Fang Que ◽

Zhen-Bo Wang ◽

Yin Zhang ◽

Yuan Xue ◽

...

Keyword(s):

High Performance ◽

Diffusion Rate ◽

Li Ion Batteries ◽

Li Ion Battery ◽

Cycle Stability ◽

Ion Diffusion ◽

Irreversible Capacity ◽

Capacity Loss ◽

Li Ion ◽

Resultant Material

We report an effective approach to fabricate layered-spinel capped nanotube assembled 3D Li-rich hierarchitectures as a cathode material for Li-ion batteries. The resultant material exhibits a reduced first-cycle irreversible capacity loss, rapid Li-ion diffusion rate and excellent cycle stability.

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A novel nanosphere-in-nanotube iron phosphide Li-ion battery anode displaying a long cycle life, recoverable rate-performance, and temperature tolerance

Nanoscale ◽

10.1039/d1nr05294b ◽

2021 ◽

Vol 13 (37) ◽

pp. 15624-15630

Author(s):

Jinyun Liu ◽

Ting Zhou ◽

Yan Wang ◽

Tianli Han ◽

Chaoquan Hu ◽

...

Keyword(s):

Temperature Tolerance ◽

Cycle Life ◽

Rate Performance ◽

Li Ion Batteries ◽

Li Ion Battery ◽

Iron Phosphide ◽

One Dimensional ◽

Long Cycle Life ◽

Li Ion ◽

Battery Anode

A novel nanosphere-confined one-dimensional yolk–shell anode is developed for Li-ion batteries.

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LiMn1.5Ni0.25Fe0.2M0.05O4 Nanoparticles as a Cathode Material for Rechargeable Li-Ion Batteries

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.835.149 ◽

2020 ◽

Vol 835 ◽

pp. 149-154

Author(s):

Haitham A. Abdellatif ◽

Mostafa M.M. Sanad ◽

Elsayed M. Elnaggar ◽

Mohamed M. Rashad ◽

Gamal M. El-Kady

Keyword(s):

Annealing Temperature ◽

Sol Gel ◽

Combustion Method ◽

Xrd Analysis ◽

Charge Transfer Resistance ◽

Li Ion Batteries ◽

Transfer Resistance ◽

Auto Combustion ◽

Li Ion ◽

Kinetic Diffusion

New series of spinel LiNi0.25Fe0.2Mˊ0.05Mn1.5O4 (Mˊ = Cu, Mg or Zn) cathode materials have been purposefully tailored using sol-gel auto-combustion method at low annealing temperature ~ 700°C for 3 h. The XRD analysis showed that all substituted (LNFMO-Mˊ) samples are comported with the main structure of undoped (LNFMO) with crystalline disordered spinel Fd-3m structure. TEM images revealed the octahedron-shape like morphology for the particles and the LNFMO-Zn sample has the widest particle size distribution. EIS spectra evidenced that a typical one semicircle (LNFMO-Mg) was revealed for each cell, suggesting the absence of ionic conductivity contribution. The values of charge transfer resistance (Rct) were equal to 9.3, 6.7, 6.0 and 4.4 kΩ for LNFMO, LNFMO-Cu, LNFMO-Mg indicating that the Zn-doped sample has the fastest kinetic diffusion rate and lowest activation energy of conduction.

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Preparation and Properties of Polytriphenylamine/Multi-Walled Carbon Nanotube Composite as a Cathode Material for Li-Ion Batteries

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.1512 ◽

2011 ◽

Vol 335-336 ◽

pp. 1512-1515

Author(s):

Chang Su ◽

Yin Peng Ye ◽

Xi Dan Bu ◽

Li Huan Xu ◽

Cheng Zhang

Keyword(s):

Carbon Nanotube ◽

Cathode Material ◽

Composite Cathode ◽

Charge Transfer Resistance ◽

Li Ion Batteries ◽

Multiwalled Carbon ◽

Transfer Resistance ◽

Multi Walled Carbon Nanotube ◽

Li Ion ◽

Carbon Nanotube Composite

A composite of polytriphenylamine (PTPAn) and multiwalled carbon nanotube (CNT) was prepared and tested as a cathode material in the Li-ion battery. To research the crucial role and effect of CNT in the above composite electrode, a comparing cathode of PTPAn mechanically mixed with super-p carbon was prepared and tested in the similar Li-ion batteries. The results indicate that due to good resiliency and loosing structure of the composite, PTPAn/CNT composite cathode exhibits lower charge transfer resistance (Rct), higher discharge capacity and cycle stability than those of PTPAn+super-p electrode.

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Formulation of a New Type of Electrolytes for LiNi1/3Co1/3Mn1/3O2 Cathodes Working in an Ultra-Low Temperature Range

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.455-456.258 ◽

2012 ◽

Vol 455-456 ◽

pp. 258-264 ◽

Cited By ~ 8

Author(s):

Chun Wei Yang ◽

Yong Huan Ren ◽

Bo Rong Wu ◽

Feng Wu

Keyword(s):

Ionic Conductivity ◽

Low Temperature ◽

Ethylene Carbonate ◽

Charge Transfer Resistance ◽

Li Ion Batteries ◽

Transfer Resistance ◽

Temperature Performance ◽

New Type ◽

Li Ion ◽

Low Temperature Performance

A new type of electrolytes for low temperature operation of Li-ion batteries was formulated in this work. Instead of LiPF6, LiBF4 and LiODFB were used to form this new type of electrolytes, although LiPF6 is the mostly chosen solute in the state-of-the-art Li-ion electrolytes. It was found although a LiBF4-based electrolyte had a lower ionic conductivity than that of a LiODFB-based electrolyte, a LiODFB-based electrolyte demonstrated improved low temperature performance. In particular, at-30°C, a Li-ion cell with 1M LiODFB dissolved in a 1:2:5 (wt.) propylene carbonate (PC)/ethylene carbonate (EC)/ethyl methyl carbonate (EMC) mixed solvent delivered 86% of the capacity obtained at 20°C. Furthermore, the cells with a LiODFB-based electrolyte showed lower polarization at-30°C. The above results suggest that beside the ionic conductivity of an electrolyte as a limitation to the low temperature operation of Li-ion batteries, there was interface impedance having effect on it. Analysis of cell impedance revealed that reduced charge-transfer resistance by using LiODFB resulted in improved low temperature performance of Li-ion batteries.

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Research on metallic chalcogen-functionalized monolayer-puckered V2CX2 (X = S, Se, and Te) as promising Li-ion battery anode materials

Materials Chemistry Frontiers ◽

10.1039/d1qm00422k ◽

2021 ◽

Author(s):

Chunmei Tang ◽

Xiaoxu Wang ◽

Shengli Zhang

Keyword(s):

Surface Area ◽

Anode Materials ◽

Large Surface Area ◽

Two Dimensional ◽

Li Ion Batteries ◽

Li Ion Battery ◽

Li Ion ◽

Battery Anode

Two-dimensional MXene nanomaterials are promising anode materials for Li-ion batteries (LIBs) due to their excellent conductivity, large surface area, and high Li capability.

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