TEM sample preparation of microsized LiMnO powder using an ion slicer.

The main purpose of this paper is the preparation of transmission electron microscopy (TEM) samples from the microsized powders of lithium-ion secondary batteries. To avoid artefacts during TEM sample preparation, the use of ion slicer milling for thinning and maintaining the intrinsic structure is described. Argon-ion milling techniques have been widely examined to make optimal specimens, thereby making TEM analysis more reliable.

Chitosan complements entrapment of silicon inside nitrogen doped carbon to improve and stabilize the capacity of Li-ion batteries.

A facile strategy to entrap milled silicon (m-Si) particles using nitrogen-doped-carbon (N-C@m-Si) to overcome the dramatic volume changes in Si during intercalation of lithium ions and to improve its electronic conductivity is reported here. The only natural nitrogen containing biomaterial alkaline polysaccharide, i.e.

Si Nanocrystal-Embedded SiO nanofoils: Two-Dimensional Nanotechnology-Enabled High Performance Li Storage Materials.

Silicon (Si) based materials are highly desirable to replace currently used graphite anode for lithium ion batteries. Nevertheless, its usage is still a big challenge due to poor battery performance and scale-up issue. In addition, two-dimensional (2D) architectures, which remain unresolved so far, would give them more interesting and unexpected properties.

Preparation and Characterization of the LiNiCoMnO₂ Cathode Active Material by Electrophoretic Deposition.

The electrophoretic deposition (EPD) process enables more uniform coating layers and saves time over the traditional laminating (LN) process. LiNi0.8Co0.

Surface Modification of the LiFePO Cathode for the Aqueous Rechargeable Lithium Ion Battery.

The LiFePO surface is coated with AlF via a simple chemical precipitation for aqueous rechargeable lithium ion batteries (ARLBs). During electrochemical cycling, the unfavorable side reactions between LiFePO and the aqueous electrolyte (1 M LiSO in water) leave a highly resistant passivation film, which causes a deterioration in the electrochemical performance. The coated LiFePO by 1 wt % AlF has a high discharge capacity of 132 mAh g and a highly improved cycle life, which shows 93% capacity retention even after 100 cycles, whereas the pristine LiFePO has a specific capacity of 123 mAh g and a poor capacity retention of 82%.

Progressive Assessment on the Decomposition Reaction of Na Superionic Conducting Ceramics.

The successful analysis on the microstructure of Hong-type Na superionic conducting (NASICON) ceramics revealed that it consists of several heterogeneous phases: NASICON grains with rectangular shapes, monoclinic round ZrO particles, grain boundaries, a SiO-rich vitrified phase, Na-rich amorphous particles, and pores. A dramatic microstructural evolution of NASICON ceramics was demonstrated via an in situ analysis, which showed that NASICON grains sequentially lost their original morphology and were transformed into comminuted particles (as indicated by the immersion of bulk NASICON samples into seawater at a temperature of 80 °C). The consecutive X-ray diffraction analysis represented that the significant shear stress inside NASICON ceramics caused their structural decomposition, during which HO ions occupied ceramic Na sites (predominantly along the (1̅11) and (1̅33) planes), while the original Na cations came out in the (020) plane of the NASICON ceramic crystalline structure.

Eco-friendly nitrogen-containing carbon encapsulated LiMn2O4 cathodes to enhance the electrochemical properties in rechargeable Li-ion batteries.

This study describes the synthesis of nitrogen-containing carbon (N-C) and an approach to apply the N-C material as a surface encapsulant of LiMn2O4 (LMO) cathode material. The N heteroatoms in the N-C material improve the electrochemical performance of LMO. A low-cost wet coating method was used to prepare N-C@LMO particles.

Tin phosphide-based anodes for sodium-ion batteries: synthesis via solvothermal transformation of Sn metal and phase-dependent Na storage performance.

There is a great deal of current interest in the development of rechargeable sodium (Na)-ion batteries (SIBs) for low-cost, large-scale stationary energy storage systems. For the commercial success of this technology, significant progress should be made in developing robust anode (negative electrode) materials with high capacity and long cycle life. Sn-P compounds are considered promising anode materials that have considerable potential to meet the required performance of SIBs, and they have been typically prepared by high-energy mechanical milling.

Co-intercalation of Mg(2+) and Na(+) in Na(0.69)Fe2(CN)6 as a High-Voltage Cathode for Magnesium Batteries.

Thanks to the advantages of low cost and good safety, magnesium metal batteries get the limelight as substituent for lithium ion batteries. However, the energy density of state-of-the-art magnesium batteries is not high enough because of their low operating potential; thus, it is necessary to improve the energy density by developing new high-voltage cathode materials. In this study, nanosized Berlin green Fe2(CN)6 and Prussian blue Na(0.

The High Performance of Crystal Water Containing Manganese Birnessite Cathodes for Magnesium Batteries.

Rechargeable magnesium batteries have lately received great attention for large-scale energy storage systems due to their high volumetric capacities, low materials cost, and safe characteristic. However, the bivalency of Mg(2+) ions has made it challenging to find cathode materials operating at high voltages with decent (de)intercalation kinetics. In an effort to overcome this challenge, we adopt an unconventional approach of engaging crystal water in the layered structure of Birnessite MnO2 because the crystal water can effectively screen electrostatic interactions between Mg(2+) ions and the host anions.

Environment-friendly cathodes using biopolymer chitosan with enhanced electrochemical behavior for use in lithium ion batteries.

The biopolymer chitosan has been investigated as a potential binder for the fabrication of LiFePO4 cathode electrodes in lithium ion batteries. Chitosan is compared to the conventional binder, polyvinylidene fluoride (PVDF). Dispersion of the active material, LiFePO4, and conductive agent, Super P carbon black, is tested using a viscosity analysis.

Synthesis of ordered mesoporous phenanthrenequinone-carbon via π-π interaction-dependent vapor pressure for rechargeable batteries.

The π-π interaction-dependent vapour pressure of phenanthrenequinone can be used to synthesize a phenanthrenequinone-confined ordered mesoporous carbon. Intimate contact between the insulating phenanthrenequinone and the conductive carbon framework improves the electrical conductivity. This enables a more complete redox reaction take place.

The effect of an elastic functional group in a rigid binder framework of silicon-graphite composites on their electrochemical performance.

As a means of enhancing the electrochemical performance of silicon-graphite composites, we propose a novel binder candidate that is modified by a combination of rigid and elastic functional groups on its binder framework. To provide an efficient binder that is also capable of rapid volume changes, a co-polymer binder (PAA-PAA/PMA) is synthesized by employing poly(acrylic acid) (PAA) as the main binder framework and poly(acrylic acid)-co-poly(maleic acid) (PAA/PMA) as an additional elastic polymer auxiliary. This co-polymer binder (PAA-PAA/PMA) affords a good balance of adhesive and mechanical (rigidity and elasticity) properties, which creates an excellent cycle performance with a high specific capacity (751.

SnSe alloy as a promising anode material for Na-ion batteries.

SnSe alloy is examined for the first time as an anode for Na-ion batteries, and shows excellent electrochemical performance including a high reversible capacity of 707 mA h g(-1) and stable cycle performance over 50 cycles. Upon sodiation, SnSe is changed into amorphous NaxSn nanodomains dispersed in crystalline Na2Se, and SnSe is reversibly restored after desodiation.

Hierarchical porous carbon by ultrasonic spray pyrolysis yields stable cycling in lithium-sulfur battery.

Utilizing the unparalleled theoretical capacity of sulfur reaching 1675 mAh/g, lithium-sulfur (Li-S) batteries have been counted as promising enablers of future lithium ion battery (LIB) applications requiring high energy densities. Nevertheless, most sulfur electrodes suffer from insufficient cycle lives originating from dissolution of lithium polysulfides. As a fundamental solution to this chronic shortcoming, herein, we introduce a hierarchical porous carbon structure in which meso- and macropores are surrounded by outer micropores.

Depth profile studies on nickel rich cathode material surfaces after cycling with an electrolyte containing vinylene carbonate at elevated temperature.

Lithium-ion batteries with vinylene carbonate (VC) in the electrolyte exhibit superior electrochemical and thermal behavior at elevated temperature, especially with a high Ni content in the cathode material. When VC is added to the electrolyte, polymeric species are formed on the cathode surface by a ring-opening reaction of ethylene carbonate (EC) in the electrolyte and VC, respectively. Through X-ray photoelectron spectroscopy (XPS) depth profiling, we have confirmed that these polymer layers are porous and complementary to each other.

Physical, electrochemical, and thermal properties of granulated natural graphite as anodes for Li-ion batteries.

Two different types of granulated graphites were synthesized by blending and kneading of natural graphite with pitch followed by sintering methods. The electrochemical performances of granulated graphites were investigated as anode materials for use in Li-ion batteries. The blending type granulated graphite possesses a large amount of cavities and voids, while the kneading type granulated graphite has a relatively compact microstructure, which is responsible for a high tap density.

Post oxygen treatment characteristics of coke as an anode material for Li-ion batteries.

The effect of a oxygen treatment on the electrochemical characteristics of a soft carbon anode material for Li-ion batteries was investigated. After a coke carbonization process at 1000 degrees C in an argon atmosphere, the samples were treated under a flow of oxygen gas to obtain a mild oxidation effect. After this oxygen treatment, the coke samples exhibited an improved initial coulombic efficiency and cycle performance as compared to the carbonized sample.

One-step synthesis of a sulfur-impregnated graphene cathode for lithium-sulfur batteries.

A practical route is introduced for synthesizing a sulfur-impregnated graphene composite as a promising cathode material for lithium-sulfur batteries. Sulfur particles with a size of a few microns are successfully grown in the interior spaces between randomly dispersed graphene sheets through a heterogeneous crystal growth mechanism. The proposed route not only enables the control of the particle size of active sulfur but also affords quantitative yields of composite powder in large quantities.