Publications by authors named "Poramane Chiochan"

We preconcentrate 2 M LiTFSI in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide inside a nanoporous alumina (AlO) layer as a so-called concentrated lithium semi-solid layer on a Cu current collector for anode-free Li-metal NMC90 batteries. This concept lowers the activation energy for lithium-ion transport and reduces the nucleation overpotential, enhancing the cycling stability.

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There is a controversial issue based on the particle cracking of the Ni-rich layered oxide cathode materials whether it occurs at the primary particles or the grain boundary. Herein, we found that the microcracking of NMC811 does not occur at single crystalline primary particles even abused at a severe upper cell voltage of 4.7 V having a lot of gas evolution since the single-crystal NMC811 has superior mechanical stability.

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The safety of Li-ion batteries is one of the most important factors, if not the most, determining their practical applications. We have found that free carbonate-based solvent molecules in the hybrid electrolyte system can cause severe safety concerns. Mixing ionic liquids with a carbonate-based solvent as the co-solvent at a fixed salt concentration of 1 M LiPF can lead to free carbonate-based molecules causing poor charge storage performance and safety concerns.

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The microstructure of the electrodes in lithium-ion batteries (LIBs) strongly affects their gravimetric and volumetric energy and power as well as their cycle life. Especially, the effect of the microstructure in the case of next-generation Ni-rich cathode materials has not yet been investigated. A comprehensive understanding of the calendering process is therefore necessary to find an optimal level of the electrode microstructure that can enhance lithium-ion transportation, minimize plastic deformation, and improve conductivity.

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Scalable aqueous-based supercapacitors are ideal as future energy storage technologies due to their great safety, low cost, and environmental friendliness. However, the corrosion of metal current collectors e.g.

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Transport phenomena and the solvation structure of lithium ions (Li) and hexafluorophosphate anions (PF) in electrolytes with different fluoroethylene carbonate (FEC) concentrations as well as the electrochemical performance and safety of Ni-rich Li-ion battery cells at the 18650 cylindrical cell level are investigated. We have found that the electrolyte with an optimized FEC concentration (25% v/v) can effectively enhance the transport property in terms of the Li transference number and contact ion pair (CIP) ratio leading to high performance and safety of practical 18650 cylindrical LIBs.

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A modified hydrolysed polyethylene with polyaniline was used as a dual functional interlayer/separator for high-performance lithium-sulphur batteries (LSBs) to reduce the migration of soluble polysulphide intermediates. Also, the sulphur cathode was encapsulated with carbon nanoparticles with a S@C core-shell structure using a solvent-free coating process. The chemical interaction between the imine group of the quinoid ring in the PANI structure and the polysulphides reducing the shuttle effect as well as the high electrical conductivity and less volume change of the carbon encapsulated sulphur can provide high-performance Li-S@C core-shell batteries.

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Manganese oxide nanoparticles decorated on 3D reduced graphene oxide aerogels (3D MnO /rGO) for neutral electrochemical capacitors were successfully produced by a rapid microwave reduction process within 20 s. The symmetric electrochemical capacitor of 3D MnO /rGO (Mn 3.0 at%) storing charges both electric double layer capacitance (EDLC) and pseudocapacitance mechanisms exhibits a specific capacitance of 240 F g as compared with 190 F g of that using the bare 3D rGO at 0.

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We design the Janus-like interlayer with two different functional faces for suppressing the shuttle of soluble lithium polysulfides (LPSs) in lithium-sulfur batteries (LSBs). At the front face, the conductive functionalized carbon fiber paper (f-CFP) having oxygen-containing groups i.e.

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Oxidized carbon nanosheets (OCNs), produced from black carbon nanospheres and used as a conductive additive in the supercapacitor electrodes of MnO2 nanorods, can significantly improve the charge-storage performance of the symmetric MnO2-nanorod supercapacitors with a maximum specific energy of 64 W h kg(-1) and power of 3870 W kg(-1). An optimum material composition of the supercapacitor electrode finely tuned is 60 : 30 : 10 wt% of MnO2 : OCN : PVDF, respectively. Interestingly, after 5000 charge/discharge cycles, the oxidation numbers of Mn at the positive and negative electrodes of the as-fabricated supercapacitor are +3.

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