Highly Anisotropic Thermal Transport in LiCoO2

<div>LiCoO2 is the prototype cathode in lithium ion batteries. It adopts a crystal structure with alternating Li+ and CoO2- layers along the hexagonal <0001> axis. It is well established that ionic and electronic conduction is highly anisotropic; however, little is known regarding heat transport. We analyse the phonon dispersion and lifetimes of LiCoO2 using anharmonic lattice dynamics based on quantum chemical force constants. Around room temperature, the thermal conductivity in the hexagonal ab plane of the layered cathode is ≈ 6 times higher than that along the c axis based on the phonon Boltzmann transport. The low thermal conductivity (< 10Wm-1K-1) originates from a combination of short phonon lifetimes associated with anharmonic interactions between the octahedral face-sharing CoO2- networks, as well as grain boundary scattering. The impact on heat management and thermal processes in lithium ion batteries based on layered positive electrodes is discussed.</div>

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Highly Anisotropic Thermal Transport in LiCoO2

10.26434/chemrxiv.8874404.v1 ◽

2019 ◽

Author(s):

Hui Yang ◽

Jia-Yue Yang ◽

Christopher Savory ◽

Jonathan Skelton ◽

Benjamin Morgan ◽

...

Keyword(s):

Thermal Conductivity ◽

Lithium Ion Batteries ◽

Phonon Dispersion ◽

Lithium Ion ◽

Boltzmann Transport ◽

Heat Management ◽

Positive Electrodes ◽

Anharmonic Lattice ◽

Anharmonic Interactions ◽

The Impact

<div>LiCoO2 is the prototype cathode in lithium ion batteries. It adopts a crystal structure with alternating Li+ and CoO2- layers along the hexagonal <0001> axis. It is well established that ionic and electronic conduction is highly anisotropic; however, little is known regarding heat transport. We analyse the phonon dispersion and lifetimes of LiCoO2 using anharmonic lattice dynamics based on quantum chemical force constants. Around room temperature, the thermal conductivity in the hexagonal ab plane of the layered cathode is ≈ 6 times higher than that along the c axis based on the phonon Boltzmann transport. The low thermal conductivity (< 10Wm-1K-1) originates from a combination of short phonon lifetimes associated with anharmonic interactions between the octahedral face-sharing CoO2- networks, as well as grain boundary scattering. The impact on heat management and thermal processes in lithium ion batteries based on layered positive electrodes is discussed.</div>

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Advances of 2nd Life Applications for Lithium Ion Batteries from Electric Vehicles Based on Energy Demand

Sustainability ◽

10.3390/su13105726 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5726

Author(s):

Aleksandra Wewer ◽

Pinar Bilge ◽

Franz Dietrich

Keyword(s):

Life Cycle ◽

Lithium Ion Batteries ◽

Electric Vehicles ◽

Energy Demand ◽

Lithium Ion ◽

Life Cycles ◽

Future Research ◽

Research Areas ◽

Study Results ◽

The Impact

Electromobility is a new approach to the reduction of CO2 emissions and the deceleration of global warming. Its environmental impacts are often compared to traditional mobility solutions based on gasoline or diesel engines. The comparison pertains mostly to the single life cycle of a battery. The impact of multiple life cycles remains an important, and yet unanswered, question. The aim of this paper is to demonstrate advances of 2nd life applications for lithium ion batteries from electric vehicles based on their energy demand. Therefore, it highlights the limitations of a conventional life cycle analysis (LCA) and presents a supplementary method of analysis by providing the design and results of a meta study on the environmental impact of lithium ion batteries. The study focuses on energy demand, and investigates its total impact for different cases considering 2nd life applications such as (C1) material recycling, (C2) repurposing and (C3) reuse. Required reprocessing methods such as remanufacturing of batteries lie at the basis of these 2nd life applications. Batteries are used in their 2nd lives for stationary energy storage (C2, repurpose) and electric vehicles (C3, reuse). The study results confirm that both of these 2nd life applications require less energy than the recycling of batteries at the end of their first life and the production of new batteries. The paper concludes by identifying future research areas in order to generate precise forecasts for 2nd life applications and their industrial dissemination.

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The origin of impedance rise in Ni-Rich positive electrodes for lithium-ion batteries

Journal of Power Sources ◽

10.1016/j.jpowsour.2021.229885 ◽

2021 ◽

Vol 498 ◽

pp. 229885

Author(s):

Rung-Chuan Lee ◽

Joseph Franklin ◽

Chixia Tian ◽

Dennis Nordlund ◽

Marca Doeff ◽

...

Keyword(s):

Lithium Ion Batteries ◽

Lithium Ion ◽

Positive Electrodes

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Strain Engineering of Thermal Conductivity of Two-Dimensional MoS2 and h-BN

MRS Advances ◽

10.1557/adv.2016.488 ◽

2016 ◽

Vol 1 (32) ◽

pp. 2297-2302 ◽

Cited By ~ 1

Author(s):

Xiaonan Wang ◽

Alireza Tabarraei

Keyword(s):

Thermal Conductivity ◽

Tensile Strain ◽

Phonon Dispersion ◽

Hexagonal Boron Nitride ◽

Three Dimensional ◽

Strain Engineering ◽

Normal Strain ◽

Dynamics Modeling ◽

Molecular Dynamics Modeling ◽

The Impact

ABSTRACTWe have used reverse nonequlibrium molecular dynamics modeling to study the impact of uniaxial stretching on the thermal conductivity of monolayer molybdenum disulfide (MoS2) and hexagonal boron nitride (h-BN). Our results predict an anomalous response of the thermal conductivity of these materials to normal strain. Thermal conductivity of h-BN increases under a tensile strain whereas thermal conductivity of MoS2 remains fairly constant. These are in striking contrast to the impact of tensile strain on the thermal conductivity of three dimensional materials whose thermal conductivity decreases under tensile strain. We investigate the mechanism responsible for this unexpected behavior by studying the impact of tensile strain on the phonon dispersion curves and group velocities of these materials.

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A conductive thin layer on prepared positive electrodes by vapour reaction printing for high-performance lithium-ion batteries

Journal of Materials Chemistry A ◽

10.1039/c7ta05591a ◽

2017 ◽

Vol 5 (40) ◽

pp. 21214-21222 ◽

Cited By ~ 9

Author(s):

Jinhyeok Ahn ◽

Sukeun Yoon ◽

Seul Gi Jung ◽

Jin-Heong Yim ◽

Kuk Young Cho

Keyword(s):

Electrochemical Performance ◽

Thin Layer ◽

Lithium Ion Batteries ◽

High Performance ◽

Lithium Ion ◽

Positive Electrodes ◽

Pedot Layer

By covering prepared electrodes with a PEDOT layer via VRP, the electrodes exhibited improved electrochemical performance compared to bare electrodes.

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