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Highlights FGN-182 electrolytes exhibit highly reversible Li plating/stripping with an average Coulombic efficiency reaching up to 99.56% determined from Auerbach’s test. The gas-evolution process of LiNO3 in high-voltage lithium cobalt oxide (LCO) cathodes is revealed by in situ differential electrochemical mass spectrometry. Pouch cells equipped with high-loading LCO (3 mAh cm−2) cathodes, ultrathin Li chips (25 μm), and lean electrolytes (5 g Ah−1) using optimized electrolyte (FGN-182 + 1%HTCN) demonstrate outstanding cycling performance.

Highlights: FGN-182 electrolytes exhibit highly reversible Li plating/stripping with an average Coulombic efficiency reaching up to 99.56% determined from Auerbach's test. The gas-evolution process of LiNO3 in high-voltage lithium cobalt oxide (LCO) cathodes is revealed by in situ differential electrochemical mass spectrometry. Pouch cells equipped with high-loading LCO (3 mAh cm−2) cathodes, ultrathin Li chips (25 μm), and lean electrolytes (5 g Ah−1) using optimized electrolyte (FGN-182 + 1%HTCN) demonstrate outstanding cycling performance. The lithium (Li) metal anode is widely regarded as an ideal anode material for high-energy-density batteries. However, uncontrolled Li dendrite growth often leads to unfavorable interfaces and low Coulombic efficiency (CE), limiting its broader application. Herein, an ether-based electrolyte (termed FGN-182) is formulated, exhibiting ultra-stable Li metal anodes through the incorporation of LiFSI and LiNO3 as dual salts. The synergistic effect of the dual salts facilitates the formation of a highly robust SEI film with fast Li+ transport kinetics. Notably, Li||Cu half cells exhibit an average CE reaching up to 99.56%. In particular, pouch cells equipped with high-loading lithium cobalt oxide (LCO, 3 mAh cm−2) cathodes, ultrathin Li chips (25 μm), and lean electrolytes (5 g Ah−1) demonstrate outstanding cycling performance, retaining 80% capacity after 125 cycles. To address the gas issue in the cathode under high voltage, cathode additives 1,3,6-tricyanohexane is incorporated with FGN-182; the resulting high-voltage LCO||Li (4.4 V) pouch cells can cycle steadily over 93 cycles. This study demonstrates that, even with the use of ether-based electrolytes, it is possible to simultaneously achieve significant improvements in both high Li utilization and electrolyte tolerance to high voltage by exploring appropriate functional additives for both the cathode and anode. [ABSTRACT FROM AUTHOR]

While lithium metal is highly desired as a next-generation battery material due to its theoretically highest capacity and lowest electrode potential, its practical application has been impeded by stability issues such as dendrite formation and short cycle life. Ongoing research aims to enhance the stability of lithium metal batteries for commercialization. Among the studies, research on N-based electrolyte additives, which can stabilize the solid electrolyte interface (SEI) layer and provide stability to the lithium metal surface, holds great promise. The NO3− anion in the N-based electrolyte additive causes the SEI layer on the lithium metal surface to contain compounds such as Li3N and Li2O, which not only facilitates the conduction of Li+ ions in the SEI layer but also increases its mechanical strength. However, due to challenges with the solubility of N-based electrolyte additives in carbonate-based electrolytes, extensive research has been conducted on electrolytes based on ethers. Nonetheless, the low oxidative stability of ether-based electrolytes hinders their practical application. Hence, a strategy is needed to incorporate N-based electrolyte additives into carbonate-based electrolytes. In this review, we address the challenges of lithium metal batteries and propose practical approaches for the application and development of N-based electrolyte additives. [ABSTRACT FROM AUTHOR]

Tuning the solid electrolyte interphase (SEI) formation in dual‐ion batteries is important for improving their long‐term stability. In this context, salt additives have gained importance which can sacrificially undergo reduction thereby protecting the working salt. Herein, we have considered dual salt electrolyte models of LiNO3 additive with LiPF6 and LiFSI salt to carry out ab initio molecular dynamics (AIMD) simulations and witness the evolution of SEI layer. Various contact ion pair and solvent separated ion pair models of the dual salt electrolytes have been considered to further understand the role played by solvation shells of the ions. The small size and quicker diffusion of anions through the electrolyte results in its decomposition at the electrode surface irrespective of the anion being in contact ion pair or solvated by solvent molecules. Overall, along with underlining the role of salt additives in SEI formation, this detailed study also provides insights regarding the factors beyond solvation characteristics of salt that determines the SEI growth process. [ABSTRACT FROM AUTHOR]

While lithium metal is highly desired as a next-generation battery material due to its theoretically highest capacity and lowest electrode potential, its practical application has been impeded by stability issues such as dendrite formation and short cycle life. Ongoing research aims to enhance the stability of lithium metal batteries for commercialization. Among the studies, research on N-based electrolyte additives, which can stabilize the solid electrolyte interface (SEI) layer and provide stability to the lithium metal surface, holds great promise. The NO3− anion in the N-based electrolyte additive causes the SEI layer on the lithium metal surface to contain compounds such as Li3N and Li2O, which not only facilitates the conduction of Li+ ions in the SEI layer but also increases its mechanical strength. However, due to challenges with the solubility of N-based electrolyte additives in carbonate-based electrolytes, extensive research has been conducted on electrolytes based on ethers. Nonetheless, the low oxidative stability of ether-based electrolytes hinders their practical application. Hence, a strategy is needed to incorporate N-based electrolyte additives into carbonate-based electrolytes. In this review, we address the challenges of lithium metal batteries and propose practical approaches for the application and development of N-based electrolyte additives.

Electrochemical energy storage devices have gained considerable attention recently, with “water-in-salt” electrolytes emerging as a leading contender for use in lithium-ion batteries, and supercapacitors. Herein, the lithium nitrate (LiNO3) was then introduced as an inexpensive “water-in-salt” electrolyte (explored from low to super-concentrated conditions) for fabricating the coin cell supercapacitors instead of conventional lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The transition of electrolyte properties from “salt-in-water” to “water-in-salt” e.g., viscosity, ionic conductivity, density, pH, wettability, and surface tension are demonstrated. Specifically, the 20 m LiNO3 exhibits a significantly lower viscosity (4.99 ± 0.05 cP) that is approximately 6.4 times lower than the 21 m LiTFSI (32 cP). Moreover, the LiNO3 also provides high ionic conductivity (100.6 ± 0.12 mS cm−1), which is 12.6 times higher than the LiTFSI (8 mS cm−1). The fabrication of the supercapacitor using these electrolytes in the coin cell level was then discussed, highlighted on the electrode composition and current collector-which to the best of our knowledge. The use of highly concentrated LiNO3 in conjunction with an appropriate current collector and electrode composition represents an important step forward in the development of practical supercapacitors. The as-fabricated carbon-based supercapacitor using 20 m LiNO3 exhibits a broad electrochemical stability window range of up to 2.2 V with exceptional rate capability and remarkable cyclic stability. Thus, this work will establish practical aspects of the LiNO3 as a “water-in-salt” electrolyte instead of using high-cost LiTFSI. The successful implementation of these simple techniques provides a promising path toward commercializing next-generation energy storage devices.

The Belgian reactor 1 fuel cladding is made of aluminium. If disposed of in a geological disposal repository, aluminium could come into contact with ordinary Portland cement and is going to corrode to form hydrogen gas and aluminium hydroxide. In this study, the long‐term corrosion was evaluated by electrochemical impedance spectroscopy on metal embedded in cement paste immersed in saturated calcium hydroxide solution under anaerobic conditions. Mass transfer effects were investigated by embedding aluminium in cement paste with two different porosities. LiNO3 was also added to the systems to study its corrosion inhibiting effect. After high initial values, the corrosion rate rapidly declined to reach a steady state after a few days. After ~100 days, the corrosion rate was the lowest when cement paste possessing a low porosity with the addition of LiNO3 was used and the highest when cement paste with high porosity without LiNO3 was used. Finally, scanning electron microscopy–energy X‐ray dispersive spectroscopy revealed that the corrosion product layer was thicker than expected by electrochemical impedance spectroscopy measurements, while it is only composed of aluminium and oxygen. Aluminium was found to diffuse into the cement paste close to this corrosion product layer. [ABSTRACT FROM AUTHOR]

Phosphate-based electrolyte propels the advanced battery system with high safety. Unfortunately, restricted by poor electrochemical stability, it is difficult to be compatible with advanced lithium metal anodes and Ni-rich cathodes. To alleviate these issues, the study has developed a phosphate-based localized high-concentration electrolyte with a nitrate-driven solvation structure, and the nitrate-derived N-rich inorganic interface shows excellent performance in stabilizing the LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode interface and modulating the lithium deposition morphology on the anode. The results show that the Li|| NCM811 cell has exceptional long-cycle stability of >80% capacity retention after 800 cycles at 4.3 V, 1 C. A more prominent capacity retention rate of 93.3% after 200 cycles can be reached with the high voltage of 4.5 V. While being compatible with the phosphate-based electrolyte with good flame retardancy and the good electrochemical stability of Ni-rich lithium metal battery (LMBs) systems, the present work expands the construction of anion-rich solvation structures, which is expected to promote the development of the high-performance LMBs with safety., (© 2024 Wiley‐VCH GmbH.)

Lithium metal is one of the most promising anode candidates for high‐energy‐density rechargeable batteries. However, uncontrolled lithium dendrites and other safety issues limit their practical applications. In this work, solid polymer electrolytes based on ethylene oxide and propylene oxide random copolymer (P(EO/PO)) and lithium bis(fluorosulfonyl)imide (LiFSI) with lithium nitrate (LiNO3) electrolyte additive are prepared. The LiNO3 is expected to form stable and adequate solid electrolyte interphase (SEI) layer to regulate the lithium deposition and limit lithium dendrites during cycles. As the results, it is cleared that the addition of LiNO3 to P(EO/PO)‐LiFSI‐based electrolyte effectively reduces the lithium/electrolyte interface resistance, decreases the polarization voltage during charging and discharging, and improves the cycle stability. [ABSTRACT FROM AUTHOR]

LiNO3 is a widely used salt‐additive that markedly improves the stability of ether‐based electrolytes at a Li metal anode but is generally regarded as incompatible with alkyl carbonates. Here we find that contrary to common wisdom, cyclic carbonate solvents such as ethylene carbonate can dissolve up to 0.7 M LiNO3 without any additives, largely improving the anode reversibility. We demonstrate the significance of our findings by upgrading various state‐of‐the‐art carbonate electrolytes with LiNO3, which provides large improvements in batteries composed of thin lithium (50 μm) anode and high voltage cathodes. Capacity retentions of 90.5 % after 600 cycles and 92.5 % after 200 cycles are reported for LiNi0.6Mn0.2Co0.2O2 (2 mAh cm−2, 0.5 C) and LiNi0.8Mn0.1Co0.1O2 cathode (4 mAh cm−2, 0.2 C), respectively. 1 Ah pouch cells (≈300 Wh kg−1) retain more than 87.9 % after 100 cycles at 0.5 C. This work illustrates that reforming traditional carbonate electrolytes provides a scalable, cost‐effective approach towards practical LMBs. [ABSTRACT FROM AUTHOR]

Abstract A robust solid-electrolyte interphase (SEI) enabled by electrolyte additive is a promising approach to stabilize Li anode and improve Li cycling efficiency. However, the self-sacrificial nature of SEI forming additives limits their capability to stabilize Li anode for long-term cycling. Herein, we demonstrate nanocapsules made from metal–organic frameworks for sustained release of LiNO3 as surface passivation additive in commercial carbonate-based electrolyte. The nanocapsules can offer over 10 times more LiNO3 than the solubility of LiNO3. Continuous supply of LiNO3 by nanocapsules forms a nitride-rich SEI layer on Li anode and persistently remedies SEI during prolonged cycling. As a result, lifespan of thin Li anode in 50 μm, which experiences drastic volume change and repeated SEI formation during cycling, has been notably improved. By pairing with an industry-level thick LiCoO2 cathode, practical Li-metal full cell demonstrates a remarkable capacity retention of 90% after 240 cycles, in contrast to fast capacity drop after 60 cycles in LiNO3 saturated electrolyte.

Lithium metal batteries (LMBs) must have both long cycle life and calendar life to be commercially viable. However, "trial and error" methodologies remain prevalent in contemporary research endeavors to identify favorable electrolytes. Here, a guiding principle for the selection of solvents for LMBs is proposed, which aims to achieve high Coulombic efficiency while minimizing the corrosion. For the first time, this study reveals that the dipole moment and orientation of solvent molecules have significant impacts on lithium metal reversibility and corrosion. Solvents with high dipole moments are more likely to adsorb onto lithium metal surfaces, which also influence the solid electrolyte interphase. Using this principle, the use of LiNO 3 is demonstrated as the sole salt in LiNi 0.8 Co 0.1 Mn 0.1 O 2 /Li cells can achieve excellent cycling stability. Overall, this work bridges the molecular structure of solvents to the reversibility and corrosion of lithium metal, and these concepts can be extended to other metal-based batteries., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Uncontrolled side reactions between lithium metal and organic electrolytes seriously deteriorates the stability of corresponding battery due to the non-uniform Li+ deposition. Using lithium nitrate (LiNO 3) as an additive can adjust the components in solid-electrolyte-interphase (SEI) for optimizing of lithium metal interface. However, the low solubility and rapid consumption of LiNO 3 in ester-based electrolytes limit its further application. Herein, a kind of suspension electrolyte containing micron-sized LiNO 3 particles is reported to realize a full gradient compensation against the consumption of NO 3 −. Benefiting from the uniformly dispersion of LiNO 3 particles, a SEI layer containing even-distributed Li 3 N and LiN x O y with high content is constructed that promotes the rapid and uniform plating of Li+. Consequently, the Li/Cu batteries present a polarization of only 15–20 mV, and exhibit a consistent performance for 230 cycles with the CE of 98.1%, which is 4 times than that of conventional carbonate electrolytes. In addition, the cycling life of the assembled Li/NCM811 batteries can be extended to 260 cycles with a high capacity retention of 82.4 %. A kind of suspension electrolyte containing micron-sized LiNO 3 particles is reported to realize a full gradient compensation against the consumption of NO 3 −. Benefiting from the uniformly dispersion of LiNO 3 particles, a SEI layer containing even-distributed Li 3 N and LiN x O y with high content is constructed that promotes the rapid and uniform plating of Li+. [Display omitted] • Suspension electrolyte brings a full gradient compensation of NO 3 − against the consumption on Li metal surface. • The full gradient compensation of NO 3 − promotes the uniform formation of Li 3 N and LiN x O y in SEI. • The Li + conductivity of SEI is significantly enhanced, reducing the polarization of Li/Cu batteries to only 15–20 mV. • High performance is achieved with 260 cycles in Li/NCM811 batteries at a high capacity retention of 82.4 %. [ABSTRACT FROM AUTHOR]

Given its exceptional theoretical energy density (over 2000 Wh kg -1 ), lithium||carbon fluoride (Li||CF x ) battery has garnered global attention. N-methylpyrrolidone (NMP)-based electrolyte is regarded as one promising candidate for tremendously enhancing the energy density of Li||CF x battery, provided self-discharge challenges can be resolved. This study successfully achieves a low self-discharge (LSD) and desirable electrochemical performance in Li||CF x batteries at high temperatures by utilizing NMP as the solvent and incorporating additional ingredients, including vinylene carbonate additive, as well as the dual-salt systems formed by LiBF 4 with three different Li salts, namely lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, and LiNO 3 . The experimental results unfold that the proposed methods not only minimize aluminum current collector corrosion, but also effectively passivate the Li metal anode. Among them, LiNO 3 exhibits the most pronounced effect that achieves an energy density of ≈2400 Wh kg -1 at a current density of 10 mA g -1 at 30 °C, nearly 0% capacity-fade rate after 300 h of storage at 60 °C, and the capability to maintain a stable open-circuit voltage over 4000 h. This work provides a distinctive perspective on how to realize both high energy density and LSD rates at high temperature of Li||CF x battery., (© 2023 Wiley‐VCH GmbH.)

Energy crisis and environmental pollution are the major problems faced by all the people at present time. It is time to switch over to biopolymer electrolyte-based batteries instead of synthetic due to its high cost and not being environmentally green. Biopolymer membranes have been prepared using 1 g K-carrageenan with different molar mass percentages of LiNO3 by solution casting technique using double-distilled water as a solvent. Prepared biopolymer electrolyte membranes are characterized by XRD, FTIR, DSC, and AC impedance techniques. XRD confirms the amorphous nature of the biopolymer membranes. FTIR reveals the complexation formed between 1 g K-carrageenan and LiNO3. It has been found from DSC analysis that glass transition temperature of the biopolymer membrane 1 g K-carrageenan with LiNO3 decreases due to the addition of salt compared to the pure biopolymer 1 g K-carrageenan. Biopolymer membrane 1 g K-carrageenan with 0.65 wt% of LiNO3 has got the highest ionic conductivity of 1.89 × 10−3 S cm−1. Transference number analysis has been done by Wagner's polarization method and Bruce and Vincent method. Electrochemical stability has been studied by linear sweep voltammetry. The highest conducting biopolymer membrane (1 g K-carrageenan with 0.65 wt% of LiNO3) is electrochemically stable up to 3.2 V. Lithium ion conducting battery has been constructed using the highest conducting biopolymer membrane and its performance has been analyzed. [ABSTRACT FROM AUTHOR]

SiO x /graphite anodes have attracted considerable attention in recent years due to their high specific capacity. Unfortunately, a thick solid-electrolyte-interface, which is produced by the decomposition of carbonate-based electrolytes, impedes the diffusion of lithium ions and significantly limits the rate performance of this interesting anode for practical applications. In this work, a LiNO 3 additive was introduced during the preparation of an anode electrode paste. The results of SEM, ex and in situ XRD and XPS showed that LiNO 3 decomposed into LiN x O y and Li 3 N, which deposited on the anode surface during the first discharge process. Due to the high ionic conductivity of LiN x O y and Li 3 N, the rate performance of the SiO x /graphite anode was significantly improved, showing a specific capacity nearly three times higher than that without the additive. In addition, the decomposition of the electrolyte during cycling was also suppressed by the LiN x O y and Li 3 N inorganic salts because of their low electronic conductivity and superior robustness. Our approach is facile and easy to scale up, which will be of great significance for the commercialization of SiO x /graphite anodes. Image 1 • LiNO 3 is added to SiO x /graphite paste. • LiNO 3 decomposes into LiN x O y and Li 3 N in the first cycle. • Rate performance of SiO x /graphite anode is significantly improved. [ABSTRACT FROM AUTHOR]

High‐performance lithium‐metal batteries are achieved by using a glyme‐based electrolyte enhanced with a LiNO3 additive and a LiFePO4 cathode. An optimal electrolyte formulation is selected upon detailed analysis of the electrochemical properties of various solutions formed by dissolving respectively lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and lithium bis(pentafluoroethanesulfonyl)imide (LiBETI) either in diethylene glycol dimethyl ether or in triethylene glycol dimethyl ether and by adding LiNO3. A thorough investigation shows evidence of efficient ionic transport, a wide stability window, low reactivity with lithium metal, and cathode/electrolyte interphase characteristics that are strongly dependent on the glyme chain length. The best Li/LiFePO4 battery delivers 154 mAh g−1 at C/3 (1 C=170 mA g−1) without any decay after 200 cycles. Tests at 1 C and 5 C show initial capacities of about 150 and 140 mAh g−1, a retention exceeding 70 % after 500 cycles, and suitable electrode/electrolyte interphases evolution. [ABSTRACT FROM AUTHOR]

Highlights: Nanocapsules made from metal–organic frameworks were designed for sustained release of additive (LiNO3) to passivate Li anode in commercial carbonate-based electrolyte. The nanocapsules with continuous supply of LiNO3 formed a nitride-rich solid electrolyte interphase layer on Li anode and persistently remedied the interphase during prolonged cycling. The practical Li-metal full cell delivered a prolonged lifespan with 90% capacity retention after 240 cycles which has been hardly achieved in commercial electrolyte.A robust solid-electrolyte interphase (SEI) enabled by electrolyte additive is a promising approach to stabilize Li anode and improve Li cycling efficiency. However, the self-sacrificial nature of SEI forming additives limits their capability to stabilize Li anode for long-term cycling. Herein, we demonstrate nanocapsules made from metal–organic frameworks for sustained release of LiNO3 as surface passivation additive in commercial carbonate-based electrolyte. The nanocapsules can offer over 10 times more LiNO3 than the solubility of LiNO3. Continuous supply of LiNO3 by nanocapsules forms a nitride-rich SEI layer on Li anode and persistently remedies SEI during prolonged cycling. As a result, lifespan of thin Li anode in 50 μm, which experiences drastic volume change and repeated SEI formation during cycling, has been notably improved. By pairing with an industry-level thick LiCoO2 cathode, practical Li-metal full cell demonstrates a remarkable capacity retention of 90% after 240 cycles, in contrast to fast capacity drop after 60 cycles in LiNO3 saturated electrolyte. [ABSTRACT FROM AUTHOR]

The sulfurized polyacrylonitrile (SPAN) cathode presents an excellent potential for achieving high energy density in lithium-sulfur batteries (LSBs). However, this cathode can only operate efficiently in the presence of a lithium metal anode (LMA)-unfriendly carbonic ester-based electrolyte. The challenge lies in enabling the SPAN cathode to function effectively with an LMA-friendly ether-based electrolyte. In this study, we have successfully designed a custom ether-based electrolyte by dissolving LiNO 3 in diethylene glycol dimethyl ether, supplemented with a few Li bisfluorosulfonimide additives. As anticipated, this specially formulated electrolyte exhibits remarkable compatibility with both LMA and the SPAN cathode. The resulting Li|SPAN cell exhibits impressive performance, achieving a high capacity of 1430 and 1066 mAh g−1 at 0.5 and 6 C, respectively, and maintaining long-term stability with 80 % capacity retention after 1000 cycles at 2 C. Our findings demonstrate that this designed ether-based electrolyte plays a pivotal role in facilitating the formation of a stable and highly conductive interfacial layer between both the anode and cathode, leading to enhanced LSB performance. [Display omitted] [ABSTRACT FROM AUTHOR]

For ever-growing energy demand, it is the imperative of time to develop advanced electrolyte materials which are compatible with Li + ion mobility in Lithium based batteries. In this study, polyvinyl alcohol (PVA)-LiNO3-Formamide (PLF) membrane complex has been developed for cost effective and mass fabrication of Li ion based energy storage devices. Improved Li + ion conducting PVA based polymer electrolytes in seven different PVA and LiNO3 blend compositions were prepared and characterized. Incorporation of Formamide (0.5 g) as plasticizer in the PVA-LiNO3 polymer matrix leads to a remarkable improvement in ionic conductivity (4.18 × 10−4 Scm−1) for a 0.27 g of LiNO 3 concentration at ambient temperature. Improvement in Li conductivity is due to change in crystalline nature as a consequence of PVA O-H---O intra/inter molecular H-bonding destabilization. Investigation on the trend of activation energy as a function of dopant concentration indicates that the activation energy decreases up to 0.27 g of LiNO 3. Lowest activation energy 0.21 eV is observed for this concentration. More interestingly, improved Lithium Transference Number (LITN) of 0.437 is obtained through Bruce-Vincent approach for the plasticized optimum conducting membrane (PLF4–0.27 g LiNO 3 concentration) which is better than that of the commercially available Li batteries. Underlying molecular level interactions in the models of PVA and its complexes were explored using M05-2×/6–31 + G (d,f) levels of theory and NCI analysis. From the least interaction energy of PVA-Formamide complex, it is inferred that metal-Oxygen coordination contributes much for the stabilization of PVA-LiNO 3 -Formamide, PVA-LiNO 3 , Formamide-LiNO 3 complexes. [Display omitted] • A hydrophilic PVA based Lithium ion conducting membrane has been prepared to develop cost effective energy storage device with environment friendly approach • Formamide has been considered as a plasticizing agent which improved the ionic conductivity in the membrane as this system has not been used before as a plasticizer in solid state electrolyte membrane. • Non-covalent forces involved in the molecular complexes were explored through electronic structure calculations and IGM analysis. [ABSTRACT FROM AUTHOR]

In this paper, we report a facile method for the in situ deposition of a thin solid electrolyte layer on the surface of anode materials, which can significantly improve the rate capability and reduce the time for reaching capacity maximum. The thin solid electrolyte layer (∼8 nm) is formed by adding a small amount of LiNO 3 into the anode materials; the added LiNO 3 decomposes irreversibly into Li 3 N and LiN x O y on the surface of the anode materials during the first cycle, facilitating fast diffusion of lithium ions and limiting the formation of the surface electrolyte interface films. This is verified by adding LiNO 3 into graphite half-cells which shows a fast activation process at high current density: in particular, the charge capacity reaches its maximum after only ∼30 and ∼40 cycles at 170 and 340 mA g−1, respectively, compared to ∼50 and ∼80 cycles for the graphite half-cell. Furthermore, the LiNO 3 additive results in high capacity retention at high C-rates, with a value of 82.4% at 680 mA g−1, compared with 22.4% for the graphite half-cell. The facile and low-cost method reported here is expected to be readily applicable to other electrode materials for high-performance lithium-ion batteries. Image 1 • A thin solid electrolyte layer is in situ deposited via introducing LiNO 3 additive. • The LiNO 3 additive decomposes irreversibly into Li 3 N and LiN x O y. • The LiNiO 3 additive results in high capacity retention at high C-rates. [ABSTRACT FROM AUTHOR]

Developing electrolytes qualified for high-voltage (>4 V vs Li/Li+) conditions is of great significance for high-energy density Li-metal batteries (LMBs). Carbonate-based electrolytes possess high oxidation stability, whereas the uneven Li deposition, low Coulombic efficiency (CE) and poor anodic stability of such electrolytes severely impede the practical application in high-voltage LMBs. Herein, a 1.8 M lithium bis(trifluoromethanesulphonyl)imide (LiTFSI)-carbonate electrolyte with high compatibility with both Li anode and high-voltage cathode is designed. LiNO 3 is introduced into the electrolyte as an additive with the assistance of CuF 2 cosolvent, which efficiently enables robust and conductive interfaces at both anode and cathode sides. As a consequence, an average CE of 98.0% is achieved for Li||Cu half-cell at 1 mA cm−2. Li||LiNi 0.8 Co 0.1 Mn 0.1 O 2 full cell fabricated with cathode areal capacity of 2.4 mAh cm−2 and 5× excess Li achieves a high capacity retention of 80.7% after 200 cycles with cut-off voltage of 4.3 V. This work provides a facile and effective approach to improve the application of carbonate-based electrolytes in high-voltage LMBs. [ABSTRACT FROM AUTHOR]

A stable solid electrolyte interphase (SEI) plays a vital role in the cyclic stability and Coulombic efficiency (CE) of high-performance lithium-sulfur (Li-S) batteries. It is recognized that the LiNO 3 additive can stabilize the SEI of the lithium electrode. However, the exact mechanism of the LiNO 3 additive on the SEI of the lithium electrode remains unclear. In this work, we first revealed the mediation mechanism of LiNO 3 additive on the dynamic evolution of the SEI on a lithium anode surface through in situ Fourier transform infrared (FTIR) spectroscopy and ab initio molecular dynamics (AIMD) methods. The FTIR and AIMD results directly proved that LiNO 3 can accelerate the reduction of lithium bis(trifluoromethyl sulfonyl)imide (LiTFSI) into small molecules rich in Li 2 O on lithium anode, thus forming a compact and stable SEI after immersing in the LiNO 3 -containing electrolyte. Moreover, the decomposition of LiTFSI and the solvent is hindered in the subsequent lithium deposition stripping process due to the stable SEI, thus leading to higher Coulombic efficiency and long-term cyclic stability. In addition, an ROSO 2 Li-like intermediate is also observed during the lithium deposition process while decomposing or diffusing away during the lithium stripping process, maintaining a dynamic formation/dissolution equilibrium of the SEI. This research provides a new insight into understanding the role of LiNO 3 in stabilizing lithium electrode. [ABSTRACT FROM AUTHOR]

With the pursuit of high energy and power density, the fast-charging capability of lithium-metal batteries has progressively been the primary focus of attention. To prevent the formation of lithium dendrites during fast charging, the ideal solid electrolyte interphase should be capable of concurrent fast Li + transport and uniform nucleation sites; however, its construction in a facile manner remains a challenge. Here, as Al 3+ has a higher charge and Al metal is lithiophilic, we tuned the Li + solvation structure by introducing LiNO 3 and aluminum ethoxide together, resulting in the dissolution of LiNO 3 and the simultaneous generation of fast ionic conductor and lithiophilic sites. Consequently, our approach facilitated the deposition of lithium metal in a uniform and chunky way, even at a high current density. As a result, the Coulombic efficiency of the Li||Cu cell increased to over 99%. Moreover, the Li||LiFePO 4 full cell demonstrated significantly enhanced cycling performance with a remarkable capacity retention of 94.5% at 4 C, far superior to the 46.1% capacity retention observed with the base electrolyte.

Lithium metal batteries (LMBs) are expected to upgrade their energy density to meet the growing battery market demand; however, intractable lithium dendrites and prominent electrode-electrolyte interface problems have been the stumbling block to their practical applications. Electrolytes play a crucial role in LMBs and are directly involved in the establishment of the electrode-electrolyte interface. In particular, low-concentration electrolytes (LCEs) can significantly save electrolyte costs, but the interface issue is more noteworthy. Here, multifunctional acetamide ( N -methyl- N -(trimethylsilyl)-trifluoroacetamide, MTA) and lithium nitrate (LiNO 3 ) additives were introduced together to enhance the performance of LMBs in LCEs. The MTA additive effectively removes the trace water and corrosive HF from the electrolyte, thus suppressing lithium salt decomposition and enhancing the stability of LCEs. Moreover, the MTA additive can construct an inorganic-rich interphase layer on the cathode/anode surface to protect the electrode. Especially, MTA can cooperate with LiNO 3 additive to suppress lithium dendrites and reduce interfacial impedance, thus effectively enhancing lithium metal anode stability. Benefiting from the introduction of MTA and LiNO 3 additives in the LCEs, the Li||NMC811 metal battery still has a capacity of 110 mA h g -1 after 500 cycles at room temperature, while the reference batteries have failed. The rate capacity and high temperature (50 °C) performance of the Li||NCM811 batteries have also been significantly improved. Significantly, this research explores a cost-effective method of using multifunctional additives to enhance LMBs' stability in LCEs.

[Display omitted] • A 17 μm solid polymer electrolyte (SPE) is prepared by in-situ polymerization. • TMP enhances the ionic conductivity and widens the electrochemical window. • LiNO 3 boosts the Li+ conductivity by weakening the interaction between Li+ and EO groups/TMP. • The SPE enables both Li||Li and LCO||Li cells work at 25 °C. The poor interfacial contact and notorious instability issues between solid electrolyte and electrodes seriously handicap the practical applications of solid-state lithium metal batteries (LMBs). In-situ polymerization is a considerable choice to upgrade the interfacial transport properties by directly curing the liquid precursor inside the cell. Herein, a ∼ 17 μm poly(ethylene glycol) methyl ether methacrylate (PEGMEA) based solid polymer electrolyte (SPE) is prepared by this method. Trimethyl phosphate (TMP) and LiNO 3 are introduced to promote the ion transport as well as enhance the electrodes/electrolyte interfacial stability. Interestingly, although LiNO 3 increases the electrolyte's glass transition temperature thus hinders the anion transport, while higher Li+ conductivity is obtained due to the weakened interaction between Li+ and its ligands, ethylene oxide (EO) and TMP. The optimal electrolyte (PTLiN1) shows an acceptable ionic conductivity of 1.2 × 10-4 S cm−1 at 55°C and lithium ion transference number (t L i + ) of 0.46, which enables the Li||Li symmetric cells to run stability within 1500 h (0.2 mA cm−2, 0.4 mAh cm−2) at 55°C and 1000 h (0.1 mA cm−2, 0.2 mAh cm−2) at 25°C. Meanwhile, the LiFePO 4 ||Li cell with PTLiN1 shows superior long cycle lifetime with a high capacity retention of 88.4% over 300 cycles at 0.5 C. The cells coupled with LiCoO 2 can even work stably under room temperature in the voltage range of 3.0 ∼ 4.3 V. Pouch cells based on PTLiN1 are also prepared and show outstanding flexibility and high security, which provides new idea for the development of economical and convenient solid-state batteries. [ABSTRACT FROM AUTHOR]

Anode-free lithium metal batteries (AFLMBs) consisting of the copper current collector, carbonated-based electrolytes, and Ni-rich cathodes can be considered potential candidates for coming-generation energy storage devices. However, the capacity fade of Ni-rich (NMC811) cathode is very fast in carbonate electrolyte. It is essential to find way to increase the lithium inventory on the cathode side so that the issue of short cycle life associated with limited lithium can be addressed for AFLMBs. Here, we introduce lithium nitrate (LiNO 3) as a cathode additive to modify the Ni-rich cathode. The additive is supposed to supply lithium inventory to compensate irreversible lithium loss and simultaneously result in the formation of stable solid electrolyte interphase (SEI) layers on the plated lithium surface. Interestingly in our AFLMBs configuration, we observe that the LiNO 3 decomposes during the high voltage operation and strongly favors formation of a good solid-electrolyte interphase (LiF and Li 3 N) and cathodic-electrolyte interphase (CEI). The result also demonstrates that the cell with lithium nitrate additive exhibits much better Coulombic efficiency (CE) (97.69% after 30 cycles) compared to the cell with no additive (89.25% after 30 cycles). This work provides a new approach to extend the cycle life of anode-free lithium metal batteries. • Develop a composite cathode with LiNO 3 additive and tested in anode free battery. • LiNO 3 increases Coulombic efficiency and cycle life by supplying Li to the anode. • Stable and inorganic-rich SEI and CEI are formed by the decomposition of LiNO 3. • LiNO 3 additive enables smooth lithium deposition when compared to bare one. • The additive helps realize high-voltage Cu.||NMC(811) cell design. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we exploit the use of a Li2S8-containing electrolyte based on a non-flammable TEGDME in a semi-liquid lithium cell, characterized by a configuration usually employed in conventional lithium ion batteries. The cell, using a sulfur-free, Super P carbon electrode shows a capacity varying from 430 mAh g−1 s to 700 mAh g−1 S. The cycling tests show that the stability of the cell is strongly affected by the voltage cutoff directly controlling the electrochemical process, in particular the polysulfide shuttle reaction. In this respect, XPS measurement shows the deposition of Li2S2 salt at the lithium electrode surface as the cell voltage cutoff is enlarged, thus suggesting that the use of the reduced voltage and capacity regimes may lead to higher stability. Under the best control regime, the 2 V cell delivers a capacity of 530 mAh g−1 S, with extremely low polarization and cycling stability extended up to 100 charge–discharge cycles. Furthermore, we demonstrate that enhanced performances may be effectively reached by adding LiNO3 salt to the electrolyte solution to form a stable, protective SEI film on the lithium surface, thus avoiding the shuttle process and increasing the cell efficiency, even under a full voltage cutoff range, i.e. extending from 1 V to 3 V. [Copyright &y& Elsevier]

Abstract: Aim of this study intends analyzing the effects of lithium additives on fresh and hardened cement mortars. In this study, mortar specimens were prepared by adding four types of additives (Li2SO4, LiNO3, Li2CO3 and LiBr) to the mixing water of the cement at 0.5%, 1%, 1.5%, 2%, 2.5% and 3% proportions by weight. The Alkali-silica reaction (ASR) of these mixtures was explored. The effects of Li2SO4, LiNO3, Li2CO3 and LİBr, which are used to control ASR induced expansion, on expansion and mechanical properties were determined. ASTM C 1260 experiment standard was used to find out the reactivity of aggregate and cement mixtures. In this experimental study, the morphology and the chemical composition of specimens exposed to ASR effect was examined by means of scanning electron microscope (SEM) and Energy Dispersive Spectroscopy (EDS). Fourteen-day readings conducted in the experimental study showed that the average maximum length change of the reference mortar bar was 0.34%, whereas the lowest average length change was 0.023% of the mortar bar with 3% Li2CO3 additive. Among the mortars that had undergone ASR, mortars containing 3% LiNO3 experienced the least strength loss. As observed in the SEM image, EDX done on dense and wide ASR cracked areas pointed to high ratios of calcium oxide and silica oxide. [Copyright &y& Elsevier]

Abstract: In this work we study the effect of LiNO3 on the Li anode and sulfur cathode, respectively, of Li/S battery by using a Li/Li symmetric cell and a liquid Li/Li2S9 cell. On the Li anode, LiNO3 participates in the formation of a stable passivation film, and the resulting passivation film grows infinitely with the consumption of LiNO3. The passivation film formed with LiNO3 is known to effectively suppress the redox shuttle of the dissolved lithium polysulfides on Li anode. On the cathode, LiNO3 undergoes a large and irreversible reduction starting at 1.6V in the first discharge, and the irreversible reduction disappears in the subsequent cycles. Moreover, the insoluble reduction products of LiNO3 on the cathode adversely affect the redox reversibility of sulfur cathode. These results indicate that both the Li anode and sulfur cathode consume LiNO3, and that the best benefit of LiNO3 to Li/S battery occurs at the potentials higher than 1.6V. By limiting the irreversible reduction of LiNO3 on the cathode, we have shown that the Li/S cell with a 0.2m LiNO3 as the co-salt can provide a stable capacity of ∼500mAhg−1. [Copyright &y& Elsevier]

Abstract: Based on the available experimental information, the AgNO3–LiNO3–NaNO3 ternary system and its low order AgNO3–LiNO3, AgNO3–NaNO3 and LiNO3–NaNO3 binary systems are thermodynamically assessed using the Calphad method. A set of parameters describing the Gibbs energies of the different phases is presented. Ternary parameters are necessary to describe the liquid phase in a neutral species model where each nitrate is treated as a constituent. Calculated phase diagrams and thermodynamical functions for the three limiting binary systems show good agreement with experimental data. In the ternary AgNO3–LiNO3–NaNO3 system we have calculated two vertical sections which are in reasonable agreement with the reported experimental data. Also, several isothermal sections are calculated. [Copyright &y& Elsevier]

Abstract: The Hückel equation used in this study to correlate the experimental activities of dilute alkali metal nitrate solutions up to a molality of about 1.5mol·kg−1 contains two parameters being dependent on the electrolyte: B [that is related closely to the ion-size parameter (a∗) in the Debye–Hückel equation] and b 1 (this parameter is the coefficient of the linear term with respect to the molality and this coefficient is related to hydration numbers of the ions of the electrolyte). In more concentrated solutions up to a molality of 7mol·kg−1, an extended Hückel equation was used, and it contains additionally a quadratic term with respect to the molality and the coefficient of this term is parameter b 2. All parameter values for the Hückel equations of LiNO3, NaNO3, and KNO3 were determined from the isopiestic data measured by Robinson for solutions of these salts against KCl solutions [J. Am. Chem. Soc. 57 (1935) 1165]. In these estimations, the Hückel parameters determined recently for KCl solutions [J. Chem. Eng. Data 54 (2009) 208] were used. The Hückel parameters for RbNO3 and CsNO3 were determined from the reported osmotic coefficients of Robinson [J. Am. Chem. Soc. 59 (1937) 84]. The resulting parameter values were tested with the vapour pressure and isopiestic data existing in the literature for alkali metal nitrate solutions. These data support well the recommended Hückel parameters up to a molality of 7.0mol·kg−1 for LiNO3 and NaNO3, up to 4.5mol·kg−1 for RbNO3, up to 3.5mol·kg−1 for KNO3, and up to 1.4mol·kg−1 for CsNO3 solutions. Reliable activity and osmotic coefficients of alkali metal nitrate solutions can, therefore, be calculated by using the new Hückel equations, and they have been tabulated at rounded molalities. The activity and osmotic coefficients obtained from these equations were compared to the values suggested by Robinson and Stokes [Electrolyte Solutions, second ed., Butterworths Scientific Publications, London, 1959], to those calculated by using the Pitzer equations with the parameter values of Pitzer and Mayorga [J. Phys. Chem. 77 (1973) 2300], and to those calculated by using the extended Hückel equation of Hamer and Wu [J. Phys. Chem. Ref. Data 1 (1972) 1047]. [Copyright &y& Elsevier]

Abstract: Different aqueous-based electrolytes have been tested in order to improve the electrochemical performance of hybrid (asymmetric) carbon/MnO2 electrochemical capacitor (EC). Chloride and bromide aqueous solutions lead to the formation of Cl2 and Br2 respectively upon oxidation of the corresponding salt, thus limiting the useful electrochemical window of the MnO2 electrode and producing gas evolution (in the case of chloride salts) detrimental to the cycling ability of an hybrid device. For sulfate and nitrate salts, MnO2 electrode exhibits a 20% increase in capacitance when lithium is used as the cation compared to sodium or potassium salts, probably due to partial lithium intercalation in the tunnels of α-MnO2 structure. The higher ionic conductivity and solubility of LiNO3 has led to the investigation of this electrolyte in carbon/MnO2 supercapacitor compared to standard hybrid cell using K2SO4. A lower resistance increase was evidenced when the temperature was decreased down to −10°C. Long term cycling ability of carbon/MnO2 supercapacitor was also evidenced with 5M LiNO3 electrolyte. [Copyright &y& Elsevier]

[Display omitted] • Low charge transfer activation energy is realized with the Li 3 N/LiF SEI layer. • Stable cycle performance with dendrite-free Li is abled in Li/Cu and Li/Li cells. • Outstanding cyclability is demonstrated in full cells using LiNi 0.8 Co 0.1 Mn 0.1 O 2. Li dendrite growth and poor Coulombic efficiency still prevent the practical use of Li metal anodes. Here, we report a stable solid electrolyte interphase (SEI) layer consisting of Li 3 N and LiF by employing lithium nitrate (LiNO 3) in carbonate electrolytes for the improved cycle performance with dendrite-free Li deposition for Li metal anodes. We demonstrate that the lower charge transfer activation energy is realized with the Li 3 N-rich SEI layer and LiF-rich SEI layer in carbonate electrolytes. With the Li 3 N and LiF composite SEI layer, outstanding improvements are achieved in that the very low charge transfer activation energy of 46.64 KJ mol−1 and stable electrochemical performances with dendrite-free Li deposition. With those benefits, the Li || Cu cell shows stable cyclability with high Coulombic efficiency of ∼ 97% at a current density of 0.5 mA cm−2 with a capacity of 0.5 mAh cm−2 over 200 cycles, and Li can be densely plated with lower porosity of 10.1 % with a plated Li of 2 mAh cm−2. Finally, the outstanding cyclability is demonstrated in full cells consisting of LiNi 0.8 Co 0.1 Mn 0.1 O 2 as a cathode and thin Li metal electrode with a thickness of 20 μm in lean electrolytes of 8 μL mAh−1. [ABSTRACT FROM AUTHOR]

Recently, silicon suboxide (SiO) attracts much attention as a promising anode material for high energy density lithium-ion batteries due to its high specific capacity. However, the active particle pulverization together with repeated rupture/reconstruction of the solid electrolyte interphase (SEI) film upon lithiation/delithiation process has been a critical issue that deteriorates the electrode cycling stability and therefore impedes its deployment in commercial batteries. To address this challenge, herein, vinylene carbonate (VC) and lithium nitrate (LiNO 3) are employed as synergistic additives to improve the electrode-electrolyte interface property. To circumvent the low solubility in carbonate solvent, LiNO 3 is incorporated directly into the electrode while VC still into the electrolyte solution. The synergistic addition of LiNO 3 and VC enhances the electrode reaction kinetics and improves significantly the cycling stability of the SiO anode. The SiO electrode with simultaneous addition of LiNO 3 and VC delivers a high reversible capacity of 1062.3 mA h g−1 and an excellent cycling performance with 94.5% capacity retention and 99.80% Coulombic efficiency for 160 cycles, demonstrating the superior effectiveness of VC and LiNO 3 in modulating the interface chemistry and structure of SiO anode. [Display omitted] • VC and LiNO 3 as electrolyte and electrode additives construct durable SEI film. • High capacity and excellent cycling stability are achieved for submicro-SiO. • The synergistic mechanism of VC and LiNO 3 additives is elucidated. [ABSTRACT FROM AUTHOR]

Through orthogonal experiment, a new type of LiClO4-LiNO3-LiBr eutectic salt with optimum mole ratio of n(LiClO4): n(LiNO3): n(LiBr) = 1.6:3.8:1.0 was prepared. The poly(lithium acrylate-acrylonitrile)/LiClO4-LiNO3-LiBr solid polymer electrolytes were prepared with poly (lithium acrylate-acrylonitrile) and LiClO4-LiNO3-LiBr eutectic salts. The effect of LiClO4-LiNO3-LiBr eutectic salts content on the conductivity of solid polymer electrolytes was studied by alternating current impedance method, and the structures of eutectic salts and solid polymer electrolytes were characterized by differential thermal analysis, infrared spectroscopy and X-ray diffractometry. The results show that the room temperature conductivity of LiClO4-LiNO3-LiBr eutectic salts reaches 3.11×10?4 S · cm?1. The poly (lithium acrylate-acrylonitrile)/LiClO4-LiNO3-LiBr solid polymer electrolytes possess the highest room temperature conductivity at 70% LiClO4-LiNO3-LiBr eutectic salts content, and exhibit lower glass transition temperature of 75 °C compared with that of poly(lithium acrylate-acrylonitrile) of 105 °C. A complex may be formed in the solid polymer electrolytes from the differential thermal analysis and infrared spectroscopy analysis. X-ray diffraction results show that the poly(lithium acrylate-acrylonitrile) can suppress the crystallization of eutectic salts in this system. [ABSTRACT FROM AUTHOR]