The method we introduced in 1992 for measuring hardness and elastic modulus by instrumented indentation techniques has widely been adopted and used in the characterization of small-scale mechanical behavior. Since its original development, the method has undergone numerous refinements and changes brought about by improvements to testing equipment and techniques as well as from advances in our understanding of the mechanics of elastic–plastic contact. Here, we review our current understanding of the mechanics governing elastic–plastic indentation as they pertain to load and depth-sensing indentation testing of monolithic materials and provide an update of how we now implement the method to make the most accurate mechanical property measurements. The limitations of the method are also discussed.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0884291400085800

Measurement of hardness and elastic modulus by instrumented indentation: Advances in understanding and refinements to methodology

Li-ion battery materials: present and future

The lithium metal battery is strongly considered to be one of the most promising candidates for high-energy-density energy storage devices in our modern and technology-based society. However, uncontrollable lithium dendrite growth induces poor cycling efficiency and severe safety concerns, dragging lithium metal batteries out of practical applications. This review presents a comprehensive overview of the lithium metal anode and its dendritic lithium growth. First, the working principles and technical challenges of a lithium metal anode are underscored. Specific attention is paid to the mechanistic understandings and quantitative models for solid electrolyte interphase (SEI) formation, lithium dendrite nucleation, and growth. On the basis of previous theoretical understanding and analysis, recently proposed strategies to suppress dendrite growth of lithium metal anode and some other metal anodes are reviewed. A section dedicated to the potential of full-cell lithium metal batteries for practical applicatio...

Toward Safe Lithium Metal Anode in Rechargeable Batteries: A Review.

Graphene has attracted tremendous research interest in recent years, owing to its exceptional properties. The scaled-up and reliable production of graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (rGO), offers a wide range of possibilities to synthesize graphene-based functional materials for various applications. This critical review presents and discusses the current development of graphene-based composites. After introduction of the synthesis methods for graphene and its derivatives as well as their properties, we focus on the description of various methods to synthesize graphene-based composites, especially those with functional polymers and inorganic nanostructures. Particular emphasis is placed on strategies for the optimization of composite properties. Lastly, the advantages of graphene-based composites in applications such as the Li-ion batteries, supercapacitors, fuel cells, photovoltaic devices, photocatalysis, as well as Raman enhancement are described (279 references).

/pdf/graphene-based-composites-540z2xd3o0.pdf

Graphene-based composites

A review of shape memory alloy research, applications and opportunities

Cycling stability is central to implementing silicon (Si) anodes in next-generation high-energy lithium-ion batteries. However, challenges remain due to the lack of effective strategies to enhance ...

Spatial Molecular Layer Deposition of Ultrathin Polyamide To Stabilize Silicon Anodes in Lithium-Ion Batteries

Preparation and characterization of amorphous and crystalline LaNi5 thin film electrodes

A belt for a continuously variable transmission (CVT) includes at least one continuous band supported against a contact face in a slot formed in each of a plurality of transverse elements of the CVT. The band has a surface positioned against the contact face. This surface is coated with chromium nitride by physical vapor deposition to reduce wear.

CVT belt with chromium nitride coating

Stacked-cup type multiwall carbon nanotubes (MWCNTs) were synthesized by floating catalyst chemical vapor deposition methods. The materials were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Electrochemical measurements showed that the stacked-cup-type MWCNTs as lithium-ion battery anode materials delivered a stable capacity of ~310 mAh g−1 at a rate of C/2 to 300 cycles. Furthermore, the materials were very stable and the coulombic efficiency exceeded 99.9 % over more than 300 cycles. Stable materials structure and the solid electrolyte interphase films were the main reasons for the durable cycling behavior, as confirmed by ex situ TEM and Raman spectroscopy, as well as electrochemical impedance spectroscopy (EIS). The results indicated that the stacked-cup-type MWCNTs produced in this work are candidate materials for lithium-ion battery anodes.

Stacked-cup-type MWCNTs as highly stable lithium-ion battery anodes

Composite electrodes consisting of cathode particles and an ion-conducting phase can address the limited ion accessibility of the cathode in high-energy all-solid-state lithium batteries. In this Letter, we discuss the microstructure–conductivity relationship in an electronic–ionic composite with a focus on lithium ion conductivity. This study is the first step toward further understanding of electrochemical reactions in all solid multiphase systems.

/pdf/charge-transport-in-electronic-ionic-composites-41qdq77hbg.pdf

Yang-Tse Cheng

Papers

Spatial Molecular Layer Deposition of Ultrathin Polyamide To Stabilize Silicon Anodes in Lithium-Ion Batteries

Preparation and characterization of amorphous and crystalline LaNi5 thin film electrodes

CVT belt with chromium nitride coating

Stacked-cup-type MWCNTs as highly stable lithium-ion battery anodes

Charge Transport in Electronic-Ionic Composites.