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Abstract: Lithium (Li) metal is considered as the “holy grail” anode for high energy density batteries, but its applications in rechargeable Li metal batteries are still hindered by the formation of Li dendrites and low coulombic efficiency for Li plating/stripping. An effective strategy to stabilize Li metal is to embed a Li metal anode in a three‐dimensional (3D) current collector. Here, a highly porous 3D Ni substrate is reported to effectively stabilize a Li metal anode. By using a galvanostatic intermittent titration technique combined with scanning electron microscopy, the underlying mechanism of the improved stability of the Li metal anode is revealed. It is clearly demonstrated that the porous 3D Ni substrate can effectively suppress the formation of “dead” Li and support the generation of a dense surface passivation layer, while a highly porous “dead” Li layer is accumulated on the two‐dimensional (2D) Li metal, which eventually limits mass transport. X‐ray photoelectron spectroscopy results further reveal the compositional differences in the solid‐electrolyte interphase layer formed on the Li metal embedded in the porous 3D Ni substrate and the 2D Li metal substrate. These results indicate that the use of 3D conductive host is critical for the long‐term stability of Li metal batteries. [ABSTRACT FROM AUTHOR]

Significant progress has been made toward overcoming fundamental challenges in developing a silicon (Si) anode for lithium-ion batteries (LIBs). However, much less work has been reported on design and failure analysis of these batteries for practical applications. In this work, we analyzed the main factors that affect the performance of a Si anode and the energy density of pouch cells using micron-sized, nanoporous Si coated by pitch-derived carbon (p-Si/C). The volumetric energy density of the Si anode depends heavily on these factors, such as the loading of p-Si/C in the anode, the calendering density of the anode, the first-cycle coulombic efficiency, and the capacity density of the anode. The effects of other factors on the cycling performance were also revealed by postmortem analysis of cycled anodes. We found that a stable p-Si/C electrode structure is critical to avoid the disintegration of the anode structural integrity and lithium plating and enable long-term cycling. Moreover, prelithiation of Si anodes increases energy density, while the degree of prelithiation is another factor to balance with the cycle life of Si-based full cells. We propose pathways and strategies for adoption of micron-sized p-Si/C anodes in LIBs for their practical applications. • Factors affecting the performance of Si-based full cells have been investigated. • Corrosion of the Si surface largely contributes to capacity loss at early stage. • Destruction of Si anode is the main reason for the capacity loss at the late stages. • Prelithiation of Si anodes is found to worsen cycling stability if not optimized. • Pathways and strategies for adoption of Si anodes have been proposed. [ABSTRACT FROM AUTHOR]

The unstable interface of lithium metal in high energy density Li sulfur (Li–S) batteries raises concerns of poor cycling, low efficiency and safety issues, which may be addressed by using intercalation types of anode. Herein, a new prototype of Li-ion sulfur battery with high performance has been demonstrated by coupling a graphite anode with a sulfur cathode (2 mA h cm−2) after successfully addressing the interface issue of graphite in an ether based electrolyte. [ABSTRACT FROM AUTHOR]

High energy and cost-effective lithium sulfur (Li-S) battery technology has been vigorously revisited in recent years due to the urgent need of advanced energy storage technologies for green transportation and large-scale energy storage applications. However, the market penetration of Li-S batteries has been plagued due to the gap in scientific knowledge between the fundamental research and the real application need. Here, a facile and effective approach to integrate commercial carbon nanoparticles into microsized secondary ones for application in high loading sulfur electrodes is proposed The slurry with the integrated particles is easily cast into electrode laminates with practically usable mass loadings. Uniform and crack-free coating with high loading of 2-8 mg cm−2 sulfur are successfully achieved. Based on the obtained thick electrodes, the dependence of areal specific capacity on mass loading, factors influencing electrode performance, and measures used to address the existing issues are studied and discussed. [ABSTRACT FROM AUTHOR]

Due to the limited oxidation stability (<4 V) of ether oxygen in its polymer structure, polyethylene oxide (PEO)‐based polymer electrolytes are not compatible with high‐voltage (>4 V) cathodes, thus hinder further increases in the energy density of lithium (Li) metal batteries (LMBs). Here, a new type of polymer‐in‐"quasi‐ionic liquid" electrolyte is designed, which reduces the electron density on ethereal oxygens in PEO and ether solvent molecules, induces the formation of stable interfacial layers on both surfaces of the LiNi1/3Mn1/3Co1/3O2 (NMC) cathode and the Li metal anode in Li||NMC batteries, and results in a capacity retention of 88.4%, 86.7%, and 79.2% after 300 cycles with a charge cutoff voltage of 4.2, 4.3, and 4.4 V for the LMBs, respectively. Therefore, the use of "quasi‐ionic liquids" is a promising approach to design new polymer electrolytes for high‐voltage and high‐specific‐energy LMBs. [ABSTRACT FROM AUTHOR]

As electronic devices continue to become smaller, their energy sources (i.e., batteries) also need to be smaller. Typically, energy densities of batteries decrease as the battery size decreases due to the relative increase of parasitic weight such as packaging materials. In addition, the sealing methods in conventional batteries are difficult to apply to microbatteries. In this work, we developed a facile sealing method for microbatteries. The method employs a dual-sealing concept: a first rubber barrier temporally confines the organic electrolytes and a second adhesive barrier forms a hermetic seal with the battery case. With this innovative sealing approach, excellent shelf life and operation life of the batteries have been demonstrated. A minimal amount of packing materials is employed resulting in high energy densities. [ABSTRACT FROM AUTHOR]

Batteries employing lithium chemistry have been intensively investigated because of their high energy attributes which may be deployed for vehicle electrification and large-scale energy storage applications. Another important direction of battery research for micro-electronics, however, is relatively less discussed in the field but growing fast in recent years. This paper reviews chemistry and electrochemistry in different microbatteries along with their cell designs to meet the goals of their various applications. The state-of-the-art knowledge and recent progress of microbatteries for emerging micro-electronic devices may shed light on the future development of microbatteries towards high energy density and flexible design. [ABSTRACT FROM AUTHOR]