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In this study, newly designed cathode material LiFeP 1-x Si x O 4 , with silicon mixed in LiFePO 4 is investigated using the density functional theory. Its most optimized structure is the olivine structure of the Pnma space group. Bonding length show the anti-site defect which hinders Li diffusivity is prevented in the LiFeP 1-x Si x O 4. Lithium migration energy barriers in the (010) path of LiFeP 1-x Si x O 4 (x = 0, 0.5, and 1) are calculated by using nudged elastic band calculations, and the average values are determined as 0.180, 0.245, and 0.280 eV for LiFePO 4 , LiFeP 0.5 Si 0.5 O 4 , and LiFeSiO 4 , respectively. This signifies that the Li ionic diffusivity is degraded thermodynamically, which is contrary to that indicates by the calculated bonding length, however, the difference is negligibly small. Furthermore, the intercalation voltage increases up to 4.97 V, depending on the Si ratio to P, and is much higher than that of the pristine cathode materials LiFePO 4 (∼3.47 V) enabling voltage optimization by Si substitution. The energy density is proportional to the intercalation voltage, hence the energy density is increased, respectively. Finally, the Total density of states show that the electronic conductivity of LiFeP 1-x Si x O 4 (x = 0–1) is better than that of LiFePO 4. • Novel cathode material LiFeP 1-x Si x O 4 is detail designed using ab-initio study. • Optimized LiFeP 1-x Si x O 4 crystal structure is olivine structure Pnma space group. • LiFeP 1-x Si x O 4 cathode material diminishes anti-site defect and enhances electronic conductivity. • LiFeP 1-x Si x O 4 cathode material overcome low intercalation voltage and control the voltage. • LiFeP 1-x Si x O 4 cathode material improves volumetric energy density. [ABSTRACT FROM AUTHOR]

Solid Electrolyte: Strategies to Address the Safety of All Solid-State Batteries Additionally, they provide insights into the significant challenges and solutions pertaining to solid electrolytes, in terms of ionic conductivity, moisture stability, and interfacial stability. B Solid Elctrolytes b In article number 2300074, Janghyuk Moon, Min-Sik Park, Jung Ho Kim and co-workers offer an overview of solid electrolytes by categorizing them into oxide-based, sulfide-based, and polymer-based types. [Extracted from the article]

Interface Design Considering Intrinsic Properties of Dielectric Materials to Minimize Space-Charge Layer Effect between Oxide Cathode and Sulfide Solid Electrolyte in All-Solid-State Batteries (Adv. Keywords: all-solid-state batteries; dielectric materials; interface engineering; space-charge-layer; strontium titanate; sulfide-based all solid electrolytes EN all-solid-state batteries dielectric materials interface engineering space-charge-layer strontium titanate sulfide-based all solid electrolytes 1 1 1 10/13/22 20221006 NES 221006 B All-Solid-State Batteries b In article number 2201208, Woosuk Cho, Ki Jae Kim, and co-workers reveal the action mechanism of dielectric materials on the space-charge-layer (SCL) in sulfide-based all-solid-state batteries (ASSBs). All-solid-state batteries, dielectric materials, interface engineering, space-charge-layer, strontium titanate, sulfide-based all solid electrolytes. [Extracted from the article]

Despite their potential for achieving high energy density, anode-free batteries (AFBs) suffer from poor cycling stability caused by uncontrollable Li-metal deposition. To improve the reversibility of Li by physically preventing Li dendrite growth and minimizing the side reaction area between Li and the free solvent, two representative salts, lithium bis(fluorosulfonyl)imide (LiFSI) forming a robust/conductive LiF-based solid electrolyte interphase (SEI) layer, and LiNO 3 altering the deposited Li morphology from dendritic to spherical, are widely used as salts for electrolyte. However, the depletion of LiNO 3 by continuous consumption during cycling is a problem due to its low solubility. Thus, here, we report the use of high-concentration dual-salt electrolyte consisting of LiFSI and LiNO 3 for AFBs to circumvent these issues. Experimental and theoretical studies reveal that electrolytes with high-concentration LiNO 3 (up to 2 M) can be prepared by suppressing the agglomeration of LiNO 3 in 1,2-dimethoxyethane (DME) in the presence of LiFSI. Because of the densely packed Li without dendrite, the formation of a protective SEI layer, and the alleviation of electrolyte oxidation as well as Al corrosion, the AFBs with this electrolyte achieve good cycling performance by reversible operation of Li. This work demonstrates the importance of electrolyte engineering for highly stable AFBs. Image 1 • A dual-salt electrolyte with high LiNO 3 content is prepared for anode-free batteries. • Enhanced solubility of LiNO 3 is understood via experimental and theoretical studies. • Dendrite-free Li and protective SEI layers are characterized by ex-/in-situ analyses. • Cell containing electrolyte shows improved electrochemical performance. [ABSTRACT FROM AUTHOR]

The true potential of Mg–S batteries is not yet realized despite its great advantages in material cost and safety. This is due to the lethargic reaction kinetics involved in the dissociation of Mg polysulfide (MgPS) on the cathode. Herein, we propose nitrogen–doped mesoporous carbon (N d MC) materials with suitable nitrogen content and surface moieties that can be utilized as catalytic hosts to enhance polysulfide fragmentation and electron access to the redox active sites in Mg–S batteries. In controlled N d MC, the surface nitrogen atoms located at the pyridinic positions can strongly bind MgPS and accelerate the reduction of MgPS to MgS, while the graphitic wall structure facilitates facile electron transport to the reaction sites. This synergic effect enables the composite electrode made of tuned N d MC and sulfur to exhibit an enhanced reversible capacity and good cycling capacity retention in Mg–S batteries. This study offers a new strategy for improving the performance of Mg–S batteries by fine-tuning the structural properties of the carbon hosts. [Display omitted] • N-doped graphitic mesoporous carbon is utilized as a host for S 8 imbibition. • Suitable surface moiety and wall structure of carbon host is proposed. • The pyridinic-N stronly binds MgPS and accelerates its dissociation. • Synergic effect enables an enhanced performance for Mg–S batteries. [ABSTRACT FROM AUTHOR]

Lithium metal (Li) is an ideal anode for designing high-energy Li metal batteries (LMBs) due to its high specific capacity (3860 mAh g−1) and lowest electrochemical potential. However, the practical use of Li is currently impeded by uncontrollable dendritic growth during repeated Li plating and stripping, causing serious safety hazards such as electrical short circuits. To regulate Li growth behavior, various solid electrolyte interfaces (SEIs) have been explored. Despite intensive efforts, further understanding of the dendritic growth mechanism is still required. In this respect, herein, we clarify the origin and growth mechanism of Li dendrites by evaluating the critical role of an artificial SEI using a finite element method. Based on our theoretical study, we suggest that the relatively low ionic conductivity of the SEI layer is responsible for facilitating the growth of Li dendrites and the growth can be effectively suppressed by employing an artificial SEI with a higher ionic conductivity. The high-conductivity artificial SEI regulates local current distributions, directly affecting the growth of Li dendrites as determined by measuring the current density, exchange current density, and geometry. Our findings provide new insight into the design of artificial SEIs for improving the cycling performance of advanced LMBs. [Display omitted] • Li dendrite growth in Li-metal batteries was probed using a finite element method. • The effects of natural and artificial SEIs on Li growth morphology were studied. • Nonuniform current density at electrolyte-electrode interface caused dendrite growth. • Dendrite growth was suppressed by a high-ionic-conductivity artificial SEI. • The results help secure the stable cycling of Li-metal anodes in Li-metal batteries. [ABSTRACT FROM AUTHOR]