Electrochemical characterizations

Systematic physical and electrochemical characterizations revealed unique positive multifunction of a polymeric salen-type nickel(II) complex, poly[Ni(CH 3 -Salen)], as an additive for conventional cathodes in lithium-ion (Li-ion) batteries. Due to its promising electrochemical and mechanical properties, combined with its unique three-dimensional (3D) web-like electron-network structure, the redox-active-organometallic polymer can eliminate conductive carbon and replace a significant portion of the polyvinylidene fluoride (PVdF) binder that has been used in conventional LiFePO 4 cathodes. By replacing such electrochemically inactive components (i.e., carbon and PVdF), LiFePO 4 cathodes with poly[Ni(CH 3 -Salen)] deliver improved energy density compared with the conventional LiFePO 4 cathode. Facile electron transfer via large-area contact at polymer/LiFePO 4 interfaces significantly accelerates charge-transfer reactions and consequently improves the ratecapability of the cathodes. In addition, unlike PVdF, poly[Ni(CH 3 -Salen)] retains steady Young's modulus values after immersing in an electrolyte solvent, which enhances the mechanical integrity of the cathodes during the cycling of battery cells and thereby improves their cycle life. The unique multifunction of the poly[Ni(CH 3 -Salen)] will be of broad interest for its application in nextgeneration energy storage devices.

MesoporousL i 4 Ti 5 O 12 (LTO) thin film is an important anode materialf or lithium-ion batteries (LIBs). Mesoporous films could be prepared by self-assembly processes. A molten-salt-assisted self-assembly (MASA)p rocess is used to preparem esoporous thin films of LTOs. Clear solutions of CTAB, P123, LiNO 3 ,H NO 3 ,a nd Ti(OC 4 H 9) 4 in ethanolf orm gellike meso-ordered films upon either spin or spray coating. In the assembly process, the CTAB/P123 molar ratio of 14 is required to accommodate enough salt speciesi nt he mesophase,i nw hich the Li I /P123 ratio can be varied between molar ratios of 28 and 72. Calcination of the meso-ordered films produces transparent mesoporous spinel LTOf ilms that are abbreviateda sC xx-yyy-zzz or CAxx-yyy-zzz (C = calcined, CA = calcined-annealed, xx = Li I /P123 molarr atio, and yyy = calcination and zzz = annealing temperatures in Celsius) herein. Alls amples were characterized by using XRD, TEM, N 2-sorption, and Ramant echniques and it was found that, at all compositions, the LTOs pinel phase formed with or without an anatase phase as an impurity.E lectrochemical characterization of the films shows excellent performance at different current rates.T he CA40-350-450 samplep erformsb est amonga ll samples tested, yieldinga na verage discharge capacityo f(176 AE 1) mA hg À1 at C/2 and (139 AE 4) mA hg À1 at 50 C and keeping 92 %o fi ts initial discharge capacity upon 50 cycles at C/2.

MesoporousL i 4 Ti 5 O 12 (LTO) thin film is an important anode materialf or lithium-ion batteries (LIBs). Mesoporous films could be prepared by self-assembly processes. A molten-salt-assisted self-assembly (MASA)p rocess is used to preparem esoporous thin films of LTOs. Clear solutions of CTAB, P123, LiNO 3 ,H NO 3 ,a nd Ti(OC 4 H 9) 4 in ethanolf orm gellike meso-ordered films upon either spin or spray coating. In the assembly process, the CTAB/P123 molar ratio of 14 is required to accommodate enough salt speciesi nt he mesophase,i nw hich the Li I /P123 ratio can be varied between molar ratios of 28 and 72. Calcination of the meso-ordered films produces transparent mesoporous spinel LTOf ilms that are abbreviateda sC xx-yyy-zzz or CAxx-yyy-zzz (C = calcined, CA = calcined-annealed, xx = Li I /P123 molarr atio, and yyy = calcination and zzz = annealing temperatures in Celsius) herein. Alls amples were characterized by using XRD, TEM, N 2-sorption, and Ramant echniques and it was found that, at all compositions, the LTOs pinel phase formed with or without an anatase phase as an impurity.E lectrochemical characterization of the films shows excellent performance at different current rates.T he CA40-350-450 samplep erformsb est amonga ll samples tested, yieldinga na verage discharge capacityo f(176 AE 1) mA hg À1 at C/2 and (139 AE 4) mA hg À1 at 50 C and keeping 92 %o fi ts initial discharge capacity upon 50 cycles at C/2.

MesoporousL i 4 Ti 5 O 12 (LTO) thin film is an important anode materialf or lithium-ion batteries (LIBs). Mesoporous films could be prepared by self-assembly processes. A molten-salt-assisted self-assembly (MASA)p rocess is used to preparem esoporous thin films of LTOs. Clear solutions of CTAB, P123, LiNO 3 ,H NO 3 ,a nd Ti(OC 4 H 9 ) 4 in ethanolf orm gellike meso-ordered films upon either spin or spray coating. In the assembly process, the CTAB/P123 molar ratio of 14 is required to accommodate enough salt speciesi nt he mesophase,i nw hich the Li I /P123 ratio can be varied between molar ratios of 28 and 72. Calcination of the meso-ordered films produces transparent mesoporous spinel LTOf ilms that are abbreviateda sC xx-yyy-zzz or CAxx-yyy-zzz (C = calcined, CA = calcined-annealed, xx = Li I /P123 molarr atio, and yyy = calcination and zzz = annealing temperatures in Celsius) herein. Alls amples were characterized by using XRD, TEM, N 2 -sorption, and Ramant echniques and it was found that, at all compositions, the LTOs pinel phase formed with or without an anatase phase as an impurity.E lectrochemical characterization of the films shows excellent performance at different current rates.T he CA40-350-450 samplep erformsb est amonga ll samples tested, yieldinga na verage discharge capacityo f( 176 AE 1) mA hg À1 at C/2 and (139 AE 4) mA hg À1 at 50 C and keeping 92 %o fi ts initial discharge capacity upon 50 cycles at C/2.

MesoporousL i 4 Ti 5 O 12 (LTO) thin film is an important anode materialf or lithium-ion batteries (LIBs). Mesoporous films could be prepared by self-assembly processes. A molten-salt-assisted self-assembly (MASA)p rocess is used to preparem esoporous thin films of LTOs. Clear solutions of CTAB, P123, LiNO 3 ,H NO 3 ,a nd Ti(OC 4 H 9) 4 in ethanolf orm gellike meso-ordered films upon either spin or spray coating. In the assembly process, the CTAB/P123 molar ratio of 14 is required to accommodate enough salt speciesi nt he mesophase,i nw hich the Li I /P123 ratio can be varied between molar ratios of 28 and 72. Calcination of the meso-ordered films produces transparent mesoporous spinel LTOf ilms that are abbreviateda sC xx-yyy-zzz or CAxx-yyy-zzz (C = calcined, CA = calcined-annealed, xx = Li I /P123 molarr atio, and yyy = calcination and zzz = annealing temperatures in Celsius) herein. Alls amples were characterized by using XRD, TEM, N 2-sorption, and Ramant echniques and it was found that, at all compositions, the LTOs pinel phase formed with or without an anatase phase as an impurity.E lectrochemical characterization of the films shows excellent performance at different current rates.T he CA40-350-450 samplep erformsb est amonga ll samples tested, yieldinga na verage discharge capacityo f(176 AE 1) mA hg À1 at C/2 and (139 AE 4) mA hg À1 at 50 C and keeping 92 %o fi ts initial discharge capacity upon 50 cycles at C/2.

MesoporousL i 4 Ti 5 O 12 (LTO) thin film is an important anode materialf or lithium-ion batteries (LIBs). Mesoporous films could be prepared by self-assembly processes. A molten-salt-assisted self-assembly (MASA)p rocess is used to preparem esoporous thin films of LTOs. Clear solutions of CTAB, P123, LiNO 3 ,H NO 3 ,a nd Ti(OC 4 H 9) 4 in ethanolf orm gellike meso-ordered films upon either spin or spray coating. In the assembly process, the CTAB/P123 molar ratio of 14 is required to accommodate enough salt speciesi nt he mesophase,i nw hich the Li I /P123 ratio can be varied between molar ratios of 28 and 72. Calcination of the meso-ordered films produces transparent mesoporous spinel LTOf ilms that are abbreviateda sC xx-yyy-zzz or CAxx-yyy-zzz (C = calcined, CA = calcined-annealed, xx = Li I /P123 molarr atio, and yyy = calcination and zzz = annealing temperatures in Celsius) herein. Alls amples were characterized by using XRD, TEM, N 2-sorption, and Ramant echniques and it was found that, at all compositions, the LTOs pinel phase formed with or without an anatase phase as an impurity.E lectrochemical characterization of the films shows excellent performance at different current rates.T he CA40-350-450 samplep erformsb est amonga ll samples tested, yieldinga na verage discharge capacityo f(176 AE 1) mA hg À1 at C/2 and (139 AE 4) mA hg À1 at 50 C and keeping 92 %o fi ts initial discharge capacity upon 50 cycles at C/2.

Synthesis of new anodes is crucial for commercialization of rechargeable potassium-ion batteries (PIBs). In this work, the nitrogen-doped graphitic nanotubes (NGTs) were synthesized by solid-state reaction method. The microstructural characterization of synthesized NGTs revealed the presence of many active sites (provided by N-doping i.e. N p and N g) and tubular channels for the K + ion transport. The NGTs electrode was tested against potassium metal in the presence of carbonate based electrolytes. The NGTs revealed the maximum reversible capacity of 220 mA h g À1 at 20 mA g À1 current density. Furthermore, the cycle stability of NGTs was confirmed by cycling it for 200 times at the current density of 100 mA g À1 , where specific capacity of 81.2 mA h g À1 was retained. The excellent electrochemical properties (rate capability) and fast synthesis of NGTs highlights its possibility to be used against post-lithium metal anodes in near future.

A critical aging mechanism in lithium-ion batteries is the decomposition of the electrolyte at the negative electrode forming a solid electrolyte interphase (SEI) layer that increases impedance and consumes cyclable lithium. In contrast to the typical nanometer SEI layer generally discussed, this paper reports on the formation of a micrometer thick film on top of and within the upper part of a porous graphite electrode in a deep-cycled commercial cylindrical LiFePO 4 /graphite cell. Morphological, chemical, and electrochemical characterizations were performed by means of cross-sectional electron microscopy in combination with energy dispersive X-ray spectroscopy and focused ion-beam milling, time-of-flight secondary ion mass spectrometry, and electrochemical impedance spectroscopy (EIS) to evaluate the properties and impact of the uneven film. It is shown that the film is enriched in P−O and carbonate species but is otherwise similar in composition to the thin SEI formed on a calendar-aged electrode and clogs the pores in the electrode closest to the separator. Performance evaluation by physics-based EIS modeling supports a local porosity decrease, impeding the effective electrolyte transport in the electrode. The local variation of electrode properties implies that current distribution in the porous electrode under these cycling conditions causes inefficient material utilization and sustained uneven electrode degradation.

MesoporousL i 4 Ti 5 O 12 (LTO) thin film is an important anode materialf or lithium-ion batteries (LIBs). Mesoporous films could be prepared by self-assembly processes. A molten-salt-assisted self-assembly (MASA)p rocess is used to preparem esoporous thin films of LTOs. Clear solutions of CTAB, P123, LiNO 3 ,H NO 3 ,a nd Ti(OC 4 H 9) 4 in ethanolf orm gellike meso-ordered films upon either spin or spray coating. In the assembly process, the CTAB/P123 molar ratio of 14 is required to accommodate enough salt speciesi nt he mesophase,i nw hich the Li I /P123 ratio can be varied between molar ratios of 28 and 72. Calcination of the meso-ordered films produces transparent mesoporous spinel LTOf ilms that are abbreviateda sC xx-yyy-zzz or CAxx-yyy-zzz (C = calcined, CA = calcined-annealed, xx = Li I /P123 molarr atio, and yyy = calcination and zzz = annealing temperatures in Celsius) herein. Alls amples were characterized by using XRD, TEM, N 2-sorption, and Ramant echniques and it was found that, at all compositions, the LTOs pinel phase formed with or without an anatase phase as an impurity.E lectrochemical characterization of the films shows excellent performance at different current rates.T he CA40-350-450 samplep erformsb est amonga ll samples tested, yieldinga na verage discharge capacityo f(176 AE 1) mA hg À1 at C/2 and (139 AE 4) mA hg À1 at 50 C and keeping 92 %o fi ts initial discharge capacity upon 50 cycles at C/2.

Abstract
The [Cu(btec)0.5DMF] (H4btec= 1,2,4,5-benzenetetracarboxylate acid) was electrosynthesized on the graphite working electrode by applying catholic potential. The [Cu(btec)0.5DMF] grows on a graphite surface which results from the coordination of 1,2,4,5-benzenetetracarboxylate anions with Cu2+ cations. The electrosynthesized [Cu(btec)0.5DMF] was characterized by X-ray diffraction, scanning electron microscopy. Furthermore, POAP/Cu(btec)0.5DMF nanocomposite film electrosynthesized on the surface of the carbon paste electrode by cyclic voltammetry. Different electrochemical methods including galvanostatic charge–discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy are carried out in order to investigate the performance of the system. This work introduces new nanocomposite materials for electrochemical redox capacitors with advantages including ease synthesis, high active surface area and stability in an aqueous electrolyte.