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The development of fast‐charging lithium‐ion batteries with high energy density is hindered by the sluggish Li+ transport and substantial polarization within graphite electrodes. Herein, this study proposes that the integrated design of liquid electrolyte and solid electrolyte, a dual‐phase electrolyte (DP‐electrolyte), can facilitate Li+ transport within a thick electrode. A 3D Li3PS4 (LPS) network is constructed within the graphite electrode to form the LPS/graphite electrode. This is achieved through the in situ conversion of the P4S16 into the LPS, a process introduced during the slurry processing. Both experimental findings and simulation outcomes indicate that this design mitigates the concentration polarization due to the improved Li+ transport capability with an overall high Li+ transference number within the electrode. With a high capacity of ≈3.1 mAh cm−2 attributed to the graphite electrode, the LiNi0.6Co0.2Mn0.2O2 (NCM622)||LPS/graphite cells demonstrate superior fast‐charging capability (4 C, 15 min, charging to ≈87.7%) and stable cycling performance (4 C, 700 cycles, ≈80% capacity retention). Furthermore, they exhibit commendable low‐temperature performance. The Ah‐level pouch cell achieves 87.5% recharge in 15 min with an energy density of ≈221.5 Wh kg−1. This work offers an alternative avenue for the advancement of fast‐charging lithium‐ion batteries with practical high energy density. [ABSTRACT FROM AUTHOR]

The uneven electrochemical reactions of lithium (Li) metal anode is one of the main reasons that hinder its application in rechargeable high energy density batteries. Great progress has been achieved in homogenizing electrochemical reactions of Li metal anode in lab‐scale coin cells, however, it cannot be directly applied to pouch cells, where undesirable defects or side reactions are significantly aggravated. With carbonate electrolyte, multi‐layered negative and positive electrodes (8 × 11 cm), 1.2 Ah sulfurized polyacrylonitrile (SPAN)||Li pouch cell lost all its capacity after 40 cycles under a current of 600 mA, although its counterpart with coin cell configuration showed much higher capacity retention of 94% under the same test condition. Severe corrosion with uneven, porous, dendritic Li deposits is observed for pristine Li electrode in a pouch cell, especially in the near‐tap and the central regions with close connection with the current collector due to the locally amplified current densities. In contrast, Li/Li–Sn alloy composite electrode displays uniform and dense Li plating behavior over the entire test area with significantly suppressed parasitic reactions and gas evolution. As such, a 1.2 Ah SPAN||Li/Li–Sn cell displays much higher capacity retention than SPAN||Li cell (87% for 100 cycles vs. 0 for 40 cycles). [ABSTRACT FROM AUTHOR]

Probabilistic methods are increasingly used to quantify the effect of uncertainties on slope stability assessment. The shear strength reduction method can be used for slope stability analysis without prior assumption on the shape of the failure surfaces, and hence is an attractive method for slope stability analysis. Since it is computationally more demanding than limit equilibrium methods, reliability analysis based on the shear strength reduction method is often considered as computationally challenging. In this paper, an importance sampling method is suggested to conduct system reliability analysis of soil slopes based on the shear strength reduction method. In the suggested method, the design points are first identified using a response surface method. Then, a sampling function is constructed centred at the design points. An efficient method is used to identify the failure samples based on the shear strength reduction method. Results from two illustrative examples show that the suggested importance sampling method is an effective and robust tool for system reliability analysis of soil slopes. [ABSTRACT FROM AUTHOR]

The huge volume expansion/contraction of silicon (Si) during the lithium (Li) insertion/extraction process, which can lead to cracking and pulverization, poses a substantial impediment to its practical implementation in lithium-ion batteries (LIBs). The development of low-strain Si-based composite materials is imperative to address the challenges associated with Si anodes. In this study, we have engineered a TiSi 2 interface on the surface of Si particles via a high-temperature calcination process, followed by the introduction of an outermost carbon (C) shell, leading to the construction of a low-strain and highly stable Si@TiSi 2 @NC composite. The robust TiSi 2 interface not only enhances electrical and ionic transport but also, more critically, significantly mitigates particle cracking by restraining the stress/strain induced by volumetric variations, thus alleviating pulverization during the lithiation/delithiation process. As a result, the as-fabricated Si@TiSi 2 @NC electrode exhibits a high initial reversible capacity (2172.7 mAh g -1 at 0.2 A g -1 ), superior rate performance (1198.4 mAh g -1 at 2.0 A g -1 ), and excellent long-term cycling stability (847.0 mAh g -1 after 1000 cycles at 2.0 A g -1 ). Upon pairing with LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622), the assembled Si@TiSi 2 @NC||NCM622 pouch-type full cell exhibits exceptional cycling stability, retaining 90.1% of its capacity after 160 cycles at 0.5 C.