Role of TiO2 Phase Composition Tuned by LiOH on The Electrochemical Performance of Dual-Phase Li4Ti5O12-TiO2 Microrod as an Anode for Lithium-Ion Battery

In this study, a dual-phase Li4Ti5O12-TiO2 microrod was successfully prepared using a modified hydrothermal method and calcination process. The stoichiometry of LiOH as precursor was varied at mol ratio of 0.9, 1.1, and 1.3, to obtain the appropriate phase composition between TiO2 and Li4Ti5O12. Results show that TiO2 content has an important role in increasing the specific capacity of electrodes. The refinement of X-ray diffraction patterns by Rietveld analysis confirm that increasing the LiOH stoichiometry suppresses the TiO2 phase. In the scanning electron microscopy images, the microrod morphology was formed after calcination with diameter sizes ranging from 142.34 to 260.62 nm and microrod lengths ranging from 5.03–7.37 μm. The 0.9 LiOH sample shows a prominent electrochemical performance with the largest specific capacity of 162.72 mAh/g and 98.75% retention capacity achieved at a rate capability test of 1 C. This finding can be attributed to the appropriate amount of TiO2 that induced the smaller crystallite size, and lower charge transfer resistance, enhancing the lithium-ion insertion/extraction process and faster diffusion kinetics.

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Preparation and Electrochemical Performance of Mg2 + Doped Li4Ti5O12 Anode Materials for Lithium-Ion Batteries

Materials Science Forum ◽

10.4028/www.scientific.net/msf.960.238 ◽

2019 ◽

Vol 960 ◽

pp. 238-243

Author(s):

Ming Wang ◽

Xue Ming Zhang ◽

Ying Bo Wang ◽

Li Li Cheng ◽

Xue Lei Wang ◽

...

Keyword(s):

Electrochemical Performance ◽

Electrochemical Impedance ◽

Solid Phase ◽

Retention Rate ◽

Specific Capacity ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

Solid Phase Reaction ◽

Phase Reaction ◽

Transfer Resistance

Spinel Li4Ti5O12 (LTO) doped with Mg2+ was synthesized by solid-phase reaction method. The Mg2+ doping quantity was 3%, 6%, 9%, and 12%, respectively. The structure and electrochemical performance of the prepared LTO composites were investigated by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and galvanostatic charge-discharge tests. It was found that the doped Mg ion did not change the structure of Li4Ti5O12, and it was evenly distributed around Li4Ti5O12. When Mg2+ doping quantity increased from 3% to 12%, the internal resistance and charge transfer resistance of the composite both decreased. The first discharge specific capacity of 6%-Mg2+ doped LTO composite was 168 mAh/g, which was close to the theoretical capacity of pure lithium titanate (175 mAh/g), and the capacity retention rate was 98% after 100 cycles.

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Improved Electrochemical Performance of 0.5Li2MnO3·0.5LiNi0.5Mn0.5O2 Cathode Materials for Lithium Ion Batteries Synthesized by Ionic-Liquid-Assisted Hydrothermal Method

Frontiers in Chemistry ◽

10.3389/fchem.2020.00729 ◽

2020 ◽

Vol 8 ◽

Author(s):

Yanhong Xiang ◽

Youliang Jiang ◽

Saiqiu Liu ◽

Jianhua Wu ◽

Zhixiong Liu ◽

...

Keyword(s):

Electron Microscopy ◽

Ionic Liquid ◽

Electrochemical Performance ◽

Hydrothermal Method ◽

Cathode Materials ◽

Electrochemical Impedance ◽

Rate Capability ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

Transfer Resistance

Well-dispersed Li-rich Mn-based 0.5Li2MnO3·0.5LiNi0.5Mn0.5O2 nanoparticles with diameter ranging from 50 to 100 nm are synthesized by a hydrothermal method in the presence of N-hexyl pyridinium tetrafluoroborate ionic liquid ([HPy][BF4]). The microstructures and electrochemical performance of the prepared cathode materials are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electrochemical measurements. The XRD results show that the sample prepared by ionic-liquid-assisted hydrothermal method exhibits a typical Li-rich Mn-based pure phase and lower cation mixing. SEM and TEM images indicate that the extent of particle agglomeration of the ionic-liquid-assisted sample is lower compared to the traditional hydrothermal sample. Electrochemical test results indicate that the materials synthesized by ionic-liquid-assisted hydrothermal method exhibit better rate capability and cyclability. Besides, electrochemical impedance spectroscopy (EIS) results suggest that the charge transfer resistance of 0.5Li2MnO3· 0.5LiNi0.5Mn0.5O2 synthesized by ionic-liquid-assisted hydrothermal method is much lower, which enhances the reaction kinetics.

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Hydrothermal synthesis MoO3@CoMoO4 hybrid as an anode material for high performance lithium rechargeable batteries

Functional Materials Letters ◽

10.1142/s1793604718501047 ◽

2019 ◽

Vol 12 (01) ◽

pp. 1850104 ◽

Cited By ~ 5

Author(s):

Jinggao Wu ◽

Qi Lai ◽

Canyu Zhong

Keyword(s):

Current Density ◽

High Performance ◽

High Current Density ◽

Rate Capability ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

Rechargeable Batteries ◽

Transfer Resistance ◽

Lithium Rechargeable Batteries ◽

One Step

MoO3@CoMoO4 hybrid is fabricated by a facile one-step hydrothermal method and is used as anode for lithium-ion battery (LIB). Compared to pristine MoO3, galvanostatic charge–discharge tests show that the hybrid electrode delivered a remarkable rate capability of 586.69[Formula: see text]mAh[Formula: see text]g[Formula: see text] at the high current density of 1000[Formula: see text]mA[Formula: see text]g[Formula: see text] and a greatly enhanced cyclic capacity of 887.36[Formula: see text]mA[Formula: see text]h[Formula: see text]g[Formula: see text] after 140 cycles at the current density of 200[Formula: see text]mA[Formula: see text]g[Formula: see text] (with capacity retention, 85.3%). The superior electrochemical properties could be ascribed to the synergistic effect of MoO3 and CoO nanostructure that results in the lower charge transfer resistance and the higher Li[Formula: see text] diffusion coefficient, thus leading to high performance Li[Formula: see text] reversibility storage.

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Electrochemical Performance of Lithium-Ion Hybrid Supercapacitors based on Activated Carbon and Nanoplatelet Li4Ti5O12 Insertion Electrode Synthesized by Nanoscission Technique

MRS Proceedings ◽

10.1557/opl.2015.280 ◽

2015 ◽

Vol 1740 ◽

Author(s):

Sandeep Singh ◽

Alok C Rastogi ◽

Fredrick Omenya ◽

M Stanley Whittingham ◽

Archit Lal ◽

...

Keyword(s):

Activated Carbon ◽

Electrochemical Performance ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

Electrode Polarization ◽

Hybrid Supercapacitor ◽

Transfer Resistance ◽

Hybrid Supercapacitors ◽

Current Change ◽

Kinetic Effects

ABSTRACTElectrochemical performance of hybrid supercapacitor (HSC) utilizing surface sculpted Li4Ti5O12 (LTO) insertion electrode having nanoplatelet-like morphology and activated carbon (AC) electrode is investigated for energy storage application. Cyclic voltammetry (CV) at variable scan rates 0.5 to 60 mV.s-1 in the 0-3.2 V range show pseusocapacitive behavior and fast rate of current change indicating rapid Faradaic kinetics. Nyquist impedance study show charge transfer resistance due to kinetic effects of electron transfer and Li+ de-intercalation process at the LTO anode. Low capacity (0.2 C-1C) charge-discharge (CD) curves show high Coulomb efficiency with marginal reduction at high 5-10 C rates due to irreversibility of adsorbed PF6 anions at the electrolyte-AC interface. Galvanostatic CD cycling tests over 50 cycles at different C-rates show decline in storage capacity due to electrode polarization effects. Reduction, broadening and shift of the Raman line at 678 cm-1 from Ti-O bonds in TiO6 octahedra after cycling indicates Li insertion reactions in functioning of hybrid supercapacitor. The hybrid supercapacitor cells have shown energy density, 29 Wh.kg-1 and power density, 350 W.kg-1.

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Graphene-Wrapped FeOOH Nanorods with Enhanced Performance as Lithium-Ion Battery Anode

NANO ◽

10.1142/s1793292021500053 ◽

2020 ◽

pp. 2150005

Author(s):

Meng Sun ◽

Zhipeng Cui ◽

Huanqing Liu ◽

Sijie Li ◽

Qingye Zhang ◽

...

Keyword(s):

High Performance ◽

Electrode Materials ◽

Electronic Conductivity ◽

Rate Capability ◽

Lithium Ion ◽

Extraction Process ◽

Hybrid Structure ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Distinctive Structure

FeOOH nanorods (NRs) wrapped by reduced graphene oxide (rGO) were fabricated using a facile solvothermal method. When used as anode materials for lithium-ion batteries (LIBs), the FeOOH NRs/rGO composites show a higher capacity (490[Formula: see text]mAh g[Formula: see text] after 100 cycles at a current density of 100[Formula: see text]mA g[Formula: see text] and better rate capability than pure FeOOH NRs. The enhanced electrochemical performance can be ascribed to the hybrid structure of FeOOH and rGO. On one hand, the introduction of rGO can improve electronic conductivity and reduce charge-transfer resistance for electrode materials. On the other hand, the distinctive structure (FeOOH NRs surrounded by flexible rGO) can effectively buffer large volume change during the Li[Formula: see text] insertion/extraction process. Our work provides a feasible strategy to obtain high-performance LIBs.

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Nanohollow Carbon for Rechargeable Batteries: Ongoing Progresses and Challenges

Nano-Micro Letters ◽

10.1007/s40820-020-00521-2 ◽

2020 ◽

Vol 12 (1) ◽

Author(s):

Jiangmin Jiang ◽

Guangdi Nie ◽

Ping Nie ◽

Zhiwei Li ◽

Zhenghui Pan ◽

...

Keyword(s):

Electrochemical Performance ◽

Carbon Nanostructures ◽

Active Sites ◽

Electrode Materials ◽

Mechanical Stability ◽

High Surface ◽

Specific Capacity ◽

Rate Capability ◽

Lithium Ion ◽

Rechargeable Batteries

AbstractAmong the various morphologies of carbon-based materials, hollow carbon nanostructures are of particular interest for energy storage. They have been widely investigated as electrode materials in different types of rechargeable batteries, owing to their high surface areas in association with the high surface-to-volume ratios, controllable pores and pore size distribution, high electrical conductivity, and excellent chemical and mechanical stability, which are beneficial for providing active sites, accelerating electrons/ions transfer, interacting with electrolytes, and giving rise to high specific capacity, rate capability, cycling ability, and overall electrochemical performance. In this overview, we look into the ongoing progresses that are being made with the nanohollow carbon materials, including nanospheres, nanopolyhedrons, and nanofibers, in relation to their applications in the main types of rechargeable batteries. The design and synthesis strategies for them and their electrochemical performance in rechargeable batteries, including lithium-ion batteries, sodium-ion batteries, potassium-ion batteries, and lithium–sulfur batteries are comprehensively reviewed and discussed, together with the challenges being faced and perspectives for them.

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Facilely Synthesized NiCo2O4/NiCo2O4 Nanofile Arrays Supported on Nickel Foam by a Hydrothermal Method and Their Excellent Performance for High-Rate Supercapacitance

Energies ◽

10.3390/en12071308 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1308 ◽

Cited By ~ 4

Author(s):

Anil Yedluri ◽

Eswar Araveeti ◽

Hee-Je Kim

Keyword(s):

Electrochemical Performance ◽

Specific Capacitance ◽

Nickel Foam ◽

Rate Capability ◽

Charge Transfer Resistance ◽

High Rate ◽

Transfer Resistance ◽

Electrons And Ions ◽

Binary Metal Oxides ◽

Hydrothermal Approach

NiCo2O4 nanoleaf arrays (NCO NLAs) and NiCo2O4/NiCO2O4 nanofile arrays (NCO/NCO NFAs) material was fabricated on flexible nickel foam (NF) using a facile hydrothermal approach. The electrochemical performance, including the specific capacitance, charge/discharge cycles, and lifecycle of the material after the hydrothermal treatment, was assessed. The morphological and structural behaviors of the NF@NCO NLAs and NF@NCO/NCO NFAs electrodes were analyzed using a range of analysis techniques. The as-obtained nanocomposite of the NF@NCO/NCO NFAs material delivered outstanding electrochemical performance, including an ultrahigh specific capacitance (Cs) of 2312 F g−1 at a current density of 2 mA cm−2, along with excellent cycling stability (98.7% capacitance retention after 5000 cycles at 5 mA cm−2). These values were higher than those of NF@NCO NLAs (Cs of 1950 F g−1 and 96.3% retention). The enhanced specific capacitance was attributed to the large electrochemical surface area, which allows for higher electrical conductivity and rapid transport between the electrons and ions as well as a much lower charge-transfer resistance and superior rate capability. These results clearly show that a combination of two types of binary metal oxides could be favorable for improving electrochemical performance and is expected to play a major role in the future development of nanofile-like composites (NF@NCO/NCO NFAs) for supercapacitor applications.

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Electrochemical Impedance Spectroscopy on the Performance Degradation of LiFePO4/Graphite Lithium-Ion Battery Due to Charge-Discharge Cycling under Different C-Rates

Energies ◽

10.3390/en12234507 ◽

2019 ◽

Vol 12 (23) ◽

pp. 4507 ◽

Cited By ~ 11

Author(s):

Yusuke Abe ◽

Natsuki Hori ◽

Seiji Kumagai

Keyword(s):

Charge Transfer ◽

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Electrochemical Impedance ◽

Specific Capacity ◽

Lithium Ion ◽

Performance Degradation ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Charge Discharge

Lithium-ion batteries (LIBs) using a LiFePO4 cathode and graphite anode were assembled in coin cell form and subjected to 1000 charge-discharge cycles at 1, 2, and 5 C at 25 °C. The performance degradation of the LIB cells under different C-rates was analyzed by electrochemical impedance spectroscopy (EIS) and scanning electron microscopy. The most severe degradation occurred at 2 C while degradation was mitigated at the highest C-rate of 5 C. EIS data of the equivalent circuit model provided information on the changes in the internal resistance. The charge-transfer resistance within all the cells increased after the cycle test, with the cell cycled at 2 C presenting the greatest increment in the charge-transfer resistance. Agglomerates were observed on the graphite anodes of the cells cycled at 2 and 5 C; these were more abundantly produced in the former cell. The lower degradation of the cell cycled at 5 C was attributed to the lowered capacity utilization of the anode. The larger cell voltage drop caused by the increased C-rate reduced the electrode potential variation allocated to the net electrochemical reactions, contributing to the charge-discharge specific capacity of the cells.

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Increasing Electrical Conductivity of Free-Standing Sulfurized Polyacrylonitrile Cathode for Lithium–Sulfur Batteries

Science of Advanced Materials ◽

10.1166/sam.2020.3789 ◽

2020 ◽

Vol 12 (10) ◽

pp. 1441-1445

Author(s):

Huihun Kim ◽

Seon-Hwa Choe ◽

Milan K. Sadan ◽

Changhyeon Kim ◽

Kwon-Koo Cho ◽

...

Keyword(s):

Electrical Conductivity ◽

Specific Capacity ◽

Rate Capability ◽

Charge Transfer Resistance ◽

Acetylene Black ◽

Free Standing ◽

Transfer Resistance ◽

Lithium Sulfur Batteries ◽

Multi Walled Carbon Nanotubes ◽

Lithium Sulfur

Sulfurized polyacrylonitrile (S-PAN) is one of the best materials for addressing some of the intrinsic drawbacks of lithium–sulfur batteries, such as the intrinsic insulating properties of sulfur and the shuttle phenomenon. Moreover, while S-PAN nanofiber composites are flexible, they still presents shortcomings, such as low rate capability, which is due to their semiconductor electrical conductivity. In this study, we prepared S-PAN webs with high electrical conductivity via electrospinning using conducting agents. Additionally, we analyzed the electrochemical properties of the S-PAN webs prepared using various conducting agents (acetylene black, Ketjen black, and multi-walled carbon nanotubes). The specific capacity of the S-PAN web prepared using acetylene black was 740 mAh g–1 at the charge rate of 5 C. The excellent rate capability of S-PAN prepared using acetylene black was attributed to its low electrical resistance and low charge transfer resistance.

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Boosting the Rate and Cycling Performance of β-LixV2O5 Nanorods for Li Ion Battery by Electrode Surface Decoration

10.26434/chemrxiv.9791540.v1 ◽

2019 ◽

Author(s):

Panpan Wang ◽

Yue Du ◽

Baoyou Zhang ◽

Yanxin Yao ◽

Yuchen Xiao ◽

...

Keyword(s):

Electrochemical Performance ◽

Current Density ◽

Electrochemical Impedance ◽

Electronic Conductivity ◽

Specific Capacity ◽

Rate Capability ◽

Lithium Ion ◽

Ex Situ ◽

Practical Application ◽

Surface Decoration

The β-phase lithium vanadium oxide bronze (β-LixV2O5) with high theoretic specific capacity up to 440 mAh g-1 is considered as promising cathode materials, however, their practical application is hindered by its poor ionic and electronic conductivity, resulting in unsatisfied cyclic stability and rate capability. Herein, we report the surface decoration of β-LixV2O5 cathode using both reduced oxide graphene and ionic conductor LaPO4, which significantly promotes the electronic transfer and Li+ diffusion rate, respectively. As a result, the rGO/LaPO4/LixV2O5 composite exhibits excellent electrochemical performance in terms of high reversible specific capacity of 275.7 mAh g-1 with high capacity retention of 84.1% after 100 cycles at a current density of 60 mA g-1, and acceptable specific capacity of 170.3 mAh g-1 at high current density of 400 mA g-1. The cycled electrode is also analyzed by electrochemical impedance spectroscopy, ex-situ X-ray diffraction and scanning electron microscope, providing further insights into the improvement of electrochemical performance. Our results provide an effective approach to boost the electrochemical properties of lithium vanadates for practical application in lithium ion batteries.

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