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A slurry-coated sheet-style Si-based anode is developed for use in all-solid-state Li-ion batteries. Inexpensive, mixed-conducting polyacrylonitrile (PAN) is utilized as both binder and conductive additive, enabling Si-rich electrodes (70 wt%) to attain large reversible capacities ∼1,500 mAh g−1 (Si) at 1 C rates (>3 mA cm−2 ). Cross sectional analysis of a discharged all-solid-state halfcell indicates that the Si-PAN anode achieves the largest volumetric specific capacity ever reported for a Li-ion electrode (>1500 mAh cm−3 ). Ex situ Raman spectroscopic studies reveal that the anodes’ reversibility is attributed to the preservation of small tetrahedrally coordinated clusters within their Si nanoparticles upon discharge. We therefore argue that careful lithiation limitations should be implemented in all Si-based Li-ion anodes to preserve this local tetrahedral atomic structure. The slurry-coated sheetstyle Si-PAN anodes have been successfully cycled in all-solid-state full-cells against high-voltage nickel-rich NMC 811 composite cathodes to encourage future commercialization of similar sheet-style all-solid-state designs. [ABSTRACT FROM AUTHOR]

High capacity all-solid-state Li-ion battery anodes were prepared using an industrially scalable solution coating process. Employing commercially available polyacrylonitrile as amixed conducting binder, we have demonstrated stable cycling, high capacity electrodes with large mass loadings of tin active material. This is, to our knowledge, the first time a high capacity lithium-alloying material has been utilized in a slurry-coated sheet-style all-solid-state Li-ion battery anode. Optimization of this new electrode architecture resulted in a sheet-style anode capable of retaining an electrode specific capacity of 643.5 mAh/g after 100 charge-discharge cycles at a 0.1C rate. We believe that this work represents a step forward for slurry-coated electrodes intended for use with sulfide solid electrolytes and that the continued development of these high capacity sheet-style anodes will be critical to the commercialization of the all-solid-state Li-ion battery. [ABSTRACT FROM AUTHOR]

This study demonstrates the application of Si/C composite fibers as anode materials for all-solid-state lithium-ion batteries. Using polyacrylonitrile as the carbon precursor, Si/C fibers were prepared through electrospinning and subsequent heat-treating processes. To investigate the correlation between fiber diameter and electrochemical performance, we prepared three electrodes (A, B, C), containing Si/C fibers with ~2 μm, ~1 μm and ~0.1 μm diameters, respectively. Our results revealed that although the composition of all three electrodes was nearly the same, the Si/C fiber based electrodes exhibited better capacity retention when their fiber diameters were smaller. Normalized to the total mass of electrode composite, the solid-state half-cell prepared with the smallest diameter (~0.1 μm) Si/C fibers achieved a reversible specific capacity of ~700 mAh g-1 (normalized to electrode mass) over 70 cycles. We believe that this report can serve as an informative approach toward the utilization of electrospun Si/C fibers as anode materials for all-solid-state lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The full electrochemical utilization of a crude micron-silicon anode is enabled by a simple and scalable cyclized-polyacrylonitrile (cPAN) electrode architecture paired with an innovative room temperature ionic liquid (RTIL) electrolyte. Field emission scanning electron microscopy, transmission electron microscopy and electron energy loss spectroscopy show that the resilient cPAN coating mechanically contains the cycling-induced expansion, contraction and fragmentation of the oversized silicon particles while an electrochemically robust solid-electrolyte interphase (SEI) layer prevents the perpetuation of irreversible side reactions. Prolonged electrochemical cycling data demonstrates unprecedented performance in both half-cell and full-cell configurations. Implementation of the micron-silicon anode constitutes a significant development in the evolution of safe and commercially-viable high-performance lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Herein we investigate the nanostructural evolution of Silicon-Titanium-Nickel (Si-Ti-Ni) ternary alloy material synthesized by melt spinning process for advanced lithium-ion battery anode. The synthesized material was found to have nano-Silicon particles dispersed in the Ti4Ni4Si7 (STN) alloy buffering matrix and was characterized by X-ray diffraction (XRD), High resolution- transmission electron microscope (HR-TEM), Scanning transmission electron microscopes - energy dispersive X-ray spectrometer (STEM-EDS), and electrochemical performance test. The role of STN matrix is to accommodate the volume expansion stresses of the dispersed Si nanoparticles. However, an interesting behavior was observed during cycling. The Si nanoparticles were observed to form interconnection channels growing through the weak STN matrix cracks and evolving to a network isolating the STN matrix into small puddles. This unique nanostructural evolution of Si particles and isolation of the STN matrix failing to offer significant buffering effect to the grown Si network eventually accelerates more volume expansions during cycling due to less mechanical confinement and leads to performance degradation and poor cycle stability. [ABSTRACT FROM AUTHOR]

Pure tin (Sn) metal nano-powder is investigated as a high capacity negative electrode for rechargeable all-solid-state Li-ion batteries. Sn is used to form a fully dense network intertwining with solid electrolyte negating necessary conductive additive. Galvanostatic cycling of the Sn composite electrode delivers a reversible capacity 800 mAh g-1 of Sn with a constant coulombic efficiency over 99.2%. We report on the effect of pressure and rate upon the delithiation mechanics, drawing correlations between Sn volume increase factors and stress accumulation over the course of Sn-Li phase transformations. Due to the fabricated electrode microstructure, we are able to operate the cell at ambient pressure conditions - the next step toward commercialization of the solid-state battery. We believe that this initial work provides new opportunities to study the electrochemical expansion of Sn with the inclusion of rigid electrolyte particles. [ABSTRACT FROM AUTHOR]

In order to address the poor energy density of bulk all-solid-state lithium-ion batteries a new composite electrode preparation method is proposed. This study demonstrates the concurrent synthesis of the FeS2 active material and a glass electrolyte which is similar to the (100-x)P2S5:xLi2S system of glass electrolytes. This is accomplished through the successive mechanochemical and thermal treatments of Fe2P, S, and Li2S. The composite electrode's ionic conductivity of 5.46 x 10-5 S cm-1 at 6°C and specific energy of 1.2 Wh g-1 versus a lithium metal anode suggest that this method may provide a more intimate solid-solid interracial contact between active material and glass electrolyte. The results of this study provide a completely new perspective on the preparation of all-solid-state composite electrodes. [ABSTRACT FROM AUTHOR]

In this paper we demonstrate an all-solid-state Li-ion battery with a specific energy of 225 mWh g-1 based upon the combined mass of both the composite anode and cathode. To realize this full cell, we pair an iron sulfide and sulfur composite cathode with a Si-based anode. The anode active material is a Si-Ti-Ni alloy with good ionic and electronic conductivity that attains a stable specific capacity of 400 mAh g-1 based upon the total mass of the composite anode. To our knowledge, this is the highest stable Si-based all-solid-state anode specific capacity reported to date. To utilize both a lithium free anode and cathode, we adopt a pre-lithiation technique involving stabilized lithium metal powder. This is the first time that this technique has been demonstrated in an all-solid-state battery. [ABSTRACT FROM AUTHOR]

Cycle stability of solid-state lithium batteries (SSLBs) using a LiCoO2 cathode is improved by atomic layer deposition (ALD) on active material powder with Al2O3. SSLBs with LiCoO2/Li3.15Ge0.15P0.85S4/77.5Li2S-22.5P2S5/Li structure were constructed and tested by charge-discharge cycling at a current density of 45 μA cm-2 with a voltage window of 3.3 ~ 4.3 V (vs. Li/Li+). Capacity degradation during cycling is suppressed dramatically by employing Al2O3 ALD-coated LiCoO2 in the composite cathode. Whereas only 70% of capacity retention is achieved for uncoated LiCoO2 after 25 cycles, 90% of capacity retention is observed for LiCoO2 with ALD Al2O3 layers. Electrochemical impedance spectroscopy (EIS) and transmission electron microscopy (TEM) studies show that the presence of ALD Al2O3 layers on the surface of LiCoO2 reduces interfacial resistance development between LiCoO2 and solid state electrolyte (SSE) during cycling. [ABSTRACT FROM AUTHOR]

The effects of grain size and pattern geometry on the etching rate were investigated by using our invented pattern, and each pattern has a same height of electrodeposits regardless of pattern size after electroplating. It was found out that the logarithmic value of the etching rate is inversely linear with the pattern width at self-annealed specimen. In other words, as the pattern width decreases, the etching rate increases exponentially. Such tendency of the etching rate is owing to the result that the interfacial energies of pattern surface and grain boundary per unit volume increase by the decrease of pattern width. In contrast, the as-deposited sample shows a flat etching rate for pattern sizes. In addition, at the narrow patterns with a pattern width of below 220 nm, the etching rate in the nanocrystalline structure of the as-deposited sample is lower than in the grain grown structure of the self-annealed sample. It can be surmised that the stresses caused by interfacial energies may be relaxed by the nanocrystalline structure in the as-deposited sample. [ABSTRACT FROM AUTHOR]

A correction to the article "Tin Networked Electrode Providing Enhanced Volumetric Capacity and Pressureless Operation for All-Solid-State Li-Ion Batteries" published in the "Journal of the Electrochemical Society" is presented.