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Benefiting from high energy density of ultrahigh-nickel cathode materials and good safety of PEO-based electrolytes, PEO-based ultrahigh-nickel solid-state lithium batteries (SLMBs) are considered to be new-generation energy storage devices. However, the incompatibility of ultrahigh-nickel cathode materials and PEO-based electrolytes is the main challenge due to serious interfacial side reactions. Therefore, the modification of the cathode/electrolyte interface is crucial. Herein, the residual lithium on the surface of LiNi0.9Co0.06Mn0.04O2 is utilized to construct an interfacial coating layer by reacting with H3BO3. The in situ formed xLi2O-B2O3 coating layer (LBO1-NCM) with high ionic conductivity can be regulated with different crystal structures during the sintering process. Besides, an all-solid-state three-electrode cell is fabricated, which verifies that the xLi2O-B2O3 coating can effectively stabilize the interface. Astonishingly, uneven Li anode deposition is observed in SLMBs, which is caused by the breakage of PEO molecular chains due to the strong oxidation of the cathode, while this crosstalk is also suppressed by the xLi2O-B2O3 coating layer. Consequently, Li|PEO|LBO1-NCM achieves a substantially improved electrochemical performance, exhibiting 90.5% of capacity retention after 100 cycles for the coin cell and 80.3% of capacity retention after 200 cycles for the pouch cell. Apparently, the targeted modification of interfaces should be paid as much attention as electrolyte optimization in SLMBs.
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The matching of poly(ethylene oxide) (PEO)-based electrolytes with ultrahigh-nickel cathode materials is crucial for designing new-generation high-energy-density solid-state lithium metal batteries (SLMBs), but it is limited by serious interfacial side reactions between PEO and ultrahigh-nickel materials. Here, a high-concentration electrolyte (HCE) interface with a customized Li+ solvation sheath is constructed between the cathode and the electrolyte. It induces the formation of an anion-regulated robust cathode/electrolyte interface (CEI), reduces the unstable free-state solvent, and finally achieves the compatibility of PEO-based electrolytes with ultrahigh-nickel cathode materials. Meanwhile, the corrosion of the Al current collector caused by lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) ions is prevented by lithium difluoro(oxalato)borate (LiDFOB) ions. The synergistic effect of the double lithium salt is achieved by a well-tailored ratio of TFSI- and DFOB- in the first solvation sheath of Li+. Compared with reported PEO-based SLMBs matched with ultrahigh-nickel (Ni ≥ 90%) cathodes, the SLMB in this work delivers a high discharge specific capacity of 216.4 mAh g-1 (0.1C) even at room temperature. This work points out a direction to optimize the cathode/electrolyte interface.
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Because of the high specific capacity and low cost, Ni-rich layered oxide (NRLO) cathodes are one of the most promising cathode candidates for the next high-energy-density lithium-ion batteries. However, they face structure and interface instability challenges, especially the battery safety risk caused by using an intrinsic flammable organic liquid electrolyte. In this regard, a solid electrolyte with high safety is of great significance to promote the development of energy storage. Among them, sulfide electrolytes are considered to be the most potential substitutes for liquid electrolytes because of their high ionic conductivity and good processing properties. Nevertheless, the interfacial incompatibility between the sulfide electrolyte and NRLO cathode is the critical challenge for high-performance sulfide all-solid-state lithium batteries (ASSLBs). In this review, we summarize the problems of the Ni-rich cathode/sulfide solid electrolyte interface and the strategies to improve the interface stability. On the basis of these insights, we highlight the scientific problems and technological challenges that need to be resolved urgently and propose several potential directions to further improve the interface stability. The objective of this study is to provide a comprehensive understanding and insightful recommendations for the enhancement of the sulfide ASSLBs with NRLO cathode.
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The ether-based electrolytes show excellent performance on anodes in sodium-ion batteries (SIBs), but they still show poor compatibility with the cathodes. Here, ether electrolytes with NaBF4 as the main salt or additive were applied in NFM//HC full cells and showed enhanced performance than the electrolyte with NaPF6. Then, BF4- was found to have a stronger interaction with Na+, which could reduce the solvation of Na+ with the solvent, thus inducing the formation of the cathode electrolyte interface (CEI) and solid electrolyte interface (SEI) layers rich in inorganic species. Moreover, the morphology, structure, composition, and solubility of CEI and SEI were explored, concluding that NaBF4 could induce more stable CEI and SEI layers rich in B-containing species and inorganics. This work proposes using NaBF4 as the main salt or additive to improve the performance of ether electrolytes in NFM//HC full cells, which provides a strategy to improve the compatibility of ether-based electrolytes and cathodes.
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Low-cost and high-efficiency non-precious metal-based oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) bifunctional catalysts are the key to promoting the commercial application of metal-air batteries. Herein, a highly efficient catalyst of Fe0.18Co0.82 alloy anchoring on the nitrogen-doped porous carbon hollow sphere (FexCo1-x/N-C) is intelligently designed by spray pyrolysis (SP). The zinc in the SP-derived metal oxides and metal-organic framework volatilize at high temperature to construct a hierarchical porous structure with abundant defects and fully exposes the FeCo nanoparticles which uniformly anchor on the carbon substrate. In this structure, the coexistence of Fe0.18Co0.82 alloy and binary metal active sites (Fe-Nx/Co-Nx) guarantees the Fe0.2Co0.8/N-C catalyst exhibiting an excellent half-wave potential (E1/2 â 0.84 V) superior to 20% Pt/C for ORR and a suppressed overpotential (280 mV) than RuO2 for OER. Assembled rechargeable Zn-air battery (RZAB) demonstrates a promising specific capacity of 807.02 mAh g-1, peak power density of 159.08 mW cm-2 and durability without electrolyte circulation (550 h). This work proposes the design concept of utilizing an oxide core to in situ consume the porous carbon shell for anchoring metal active sites and construct defects, which benefits from spray pyrolysis in achieving precise control of the alloy structure and mass preparation.
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Lithium (Li) metal is regarded as a potential candidate for the next generation of lithium secondary batteries, but it has poor cycling stability with the broadly used carbonate-based electrolytes due to the uncontrollable dendritic growth and low Coulombic efficiency (CE). LiNO3 is an effective additive and its limited solubility (<800 ppm) in carbonate-based electrolytes is still a challenge, as reported. Herein, using BF3 (Lewis acid) is proposed to enhance the solubility of LiNO3 in carbonate-based electrolytes. The dissolved NO3 - can be involved in the first solvation shell of Li+, reducing the coordination number of PF6 - and EC (ethylene carbonate). In addition, the NO3 - is proved to be preferentially reduced on Li metal by differential electrochemical mass spectrometry so that the decomposition of PF6 - and EC is suppressed. Therefore, a SEI layer containing Li3N can be obtained, which exhibits high lithium-ion conductivity, achieving even and dense Li deposits. Consequently, the CE of Li||Cu cell with BF3/LiNO3 can be increased to 98.07%. Moreover, the capacity retention of Li||LiFePO4 with a low N/P ratio (3:1) is as high as 90% after 300 cycles (≈1500 h). This work paved a new way for incorporating LiNO3 into carbonate-based electrolytes and high-performance lithium metal batteries.
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This cohort study compares the use and outcomes of high-sensitivity cardiac troponin assay vs conventional troponin assay in transgender adults.
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Síndrome Coronariana Aguda , Infarto do Miocárdio , Pessoas Transgênero , Masculino , Feminino , Humanos , Síndrome Coronariana Aguda/diagnóstico , Biomarcadores , TroponinaRESUMO
Ether-based electrolytes exhibit excellent performance when applied in different anode materials of sodium ion batteries (SIBs), but their exploration on cathode material is deficient and the degradation mechanism is still undiscovered. Herein, various battery systems with different operation voltage ranges are designed to explore the electrochemical performance of ether electrolyte. It is found for the first time that the deterioration mechanism of ether electrolyte is closely related to the "redox shuttle" between cathode and low-potential anode. The "shuttle" is discovered to occur when the potential of anodes is below 0.57 V, and the gas products coming from "shuttle" intermediates are revealed by differential electrochemical mass spectrometry (DEMS). Moreover, effective inhibition strategies by protecting low-potential anodes are proposed and verified; ethylene carbonate (EC) is found to be very effective as an additive by forming an inorganics-rich solid electrolyte interphase (SEI) on low-potential anodes, thereby suppressing the deterioration of ether electrolytes. This work reveals the failure mechanism of ether-based electrolytes applied in SIBs and proposes effective strategies to suppress the "shuttle," which provides a valuable guidance for advancing the application of ether-based electrolytes in SIBs.
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Highly uniformly dense garnet type solid-state electrolyte plays a significant role in determining the performance of solid-state lithium batteries. Herein, a rational powder-covering sintering strategy is proposed and demonstrated, in which narrow-particle-size-distribution fine powder and uniform sintering temperature distribution are considered as very significant factors. It is suggested that powder materials with wider particle size distribution dramatically decrease the densified level of electrolytes. Slow temperature elevating rate and the overhead structure of bearing table are found to be beneficial to uniform densification. Moreover, the uniform densification process of sintering solid-state electrolyte is studied both microscopically and macroscopically, which can be divided into three phases according to the grain growing evolution and linear shrinkage patterns. The ionic conductivity of the as-prepared Li6.4 La3 Zr1.4 Ta0.6 O12 (LLZTO) garnet electrolyte is determined to be 0.73 mS cm-1 at 303 K with an activation energy of 0.37 eV. The Li/LLZTO/Li symmetric cell exhibits a small interfacial impedance of 8.49 Ω cm2 and a high apparent critical current density of 2.15 mA cm-2 and also can be cycled for 1000 h continuously without short-circuit. Such results indicate the good feasibility of as-proposed sintering strategy to prepare uniformly dense garnet type solid-state electrolytes for solid-state lithium batteries.
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The Ni-rich layered cathode material LiNi0.8Co0.1Mn0.1O2 (NCM811) with high specific capacity and acceptable rate performance is one of the key cathode materials for high-energy-density lithium-ion batteries. Coprecipitation, the widely utilized method in the precursor synthesis of NCM811 materials, however, suffers long synthetic processes and challenges in uniform element distribution. The spray pyrolysis method is able to prepare oxide precursors in seconds where all transition-metal elements are well distributed, but the difficulty of lithium distribution will also arise when the lithium salts are added in the subsequent sintering process. Herein, a fresh one-step spray pyrolysis approach is proposed for preparing high-performance NCM811 cathode materials by synthesizing lithium-contained precursors in which all elements are well distributed at a molecular level. The precursors with folded morphology and exceptional uniformity are successfully obtained at a low pyrolysis temperature of 300 °C by an acetate system. Furthermore, the final products commendably inherit the folded morphology of the precursors and exhibit excellent cyclic retentions of 94.6% and 88.8% after 100 and 200 cycles at 1 C (1 C = 200 mA g-1), respectively.
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Nickel-rich layered oxides LiNi x Co y Mn1- x - y O2 (x ≥ 0.8) have been recognized as the preferred cathode materials to develop lithium-ion batteries with high energy density (>300 Wh kg-1). However, the poor cycling stability and rate capability stemming from intergranular cracks and sluggish kinetics hinder their commercialization. To address such issues, a multi-scale boron penetration strategy is designed and applied on the polycrystalline LiNi0.83Co0.11Mn0.06O2 particles that are pre-treated with pore construction. The lithium-ion conductive lithium borate in grain gaps functions as the grain binder that can bear the strain/stress from anisotropic contraction/expansion, and provides more pathways for lithium-ion diffusion. As a result, the intergranular cracks are ameliorated and the lithium-ion diffusion kinetics is improved. Moreover, the coating layer separates the sensitive cathode surface and electrolyte, helping to suppress the parasitic reactions and related gas evolution. In addition, the enhanced structural stability is acquired by strong B-O bonds with trace boron doping. As a result, the boron-modified sample with an optimized boron content of 0.5% (B5-NCM) exhibits a higher initial discharge capacity of 205.5 mAh g-1 at 0.1C (1C = 200 mA g-1) and improved capacity retention of 81.7% after 100 cycles at 1C. Furthermore, the rate performance is distinctly enhanced by high lithium-ion conductive LBO (175.6 mAh g-1 for B5-NCM and 154.6 mAh g-1 for B0-NCM at 5C).
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Owing to the interacted anion and cation redox dynamics in Li2 MnO3 , the high energy density can be obtained for lithium-rich manganese-based layered transition metal (TM) oxide [Li1.2 Ni0.2 Mn0.6 O2 , LNMO]. However, irreversible migration of Mn ions and oxygen release during highly de-lithiation can destroy its layered structure, leading to voltage and capacity decline. Herein, non-TM antimony (Sb) is pinned to the TM layer of LNMO by a facile sol-gel method. High-resolution ex and in situ characterization technologies manifest that the introduction of trace Sb inhibits the migration of Mn ions, forming a more stable structure. Sb can impressively adjust the Mn-O interaction between anions and cations, beneficial to decrease the energy level of Mn 3d and O 2p orbitals and expand their band gap according to the theoretical calculation results. As a result, the discharge specific capacity and the energy density for SbLi1.2 [Ni0.2 Mn0.6 ]O2 (SLNMO) reaches as high as 301 mAh g-1 and 1019.6 Wh kg-1 at 0.1 C, respectively. Moreover, the voltage decay is reduced by 419.8 mV compared with LNMO. The regulative interaction between Mn 3d and isolated O 2p bands provides an accurate guidance for solving electrochemical performance deficiencies of lithium-rich manganese-based cathode oxide.
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Single-crystal nickel-rich cathode materials (SC-NRCMs) are the most promising candidates for next-generation power batteries which enable longer driving range and reliable safety. In this review, the outstanding advantages of SC-NRCMs are discussed systematically in aspects of structural and thermal stabilities. Particularly, the intergranular-crack-free morphology exhibits superior cycling performance and negligible parasitic reactions even under severe conditions. Besides, various synthetic methods are summarized and the relation between precursor, sintering process, and final single-crystal products are revealed, providing a full view of synthetic methods. Then, challenges of SC-NRCMs in fields of kinetics of lithium diffusion and the one particularly occurred at high voltage (intragranular cracks and aggravated parasitic reactions) are discussed. The corresponding mechanism and modifications are also referred. Through this review, it is aimed to highlight the magical morphology of SC-NRCMs for application perspective and provide a reference for following researchers.
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BACKGROUND: Pre-existing pulmonary hypertension is associated with poor outcomes after transcatheter mitral valve repair (TMVr) for mitral regurgitation (MR). However, the impact of an immediate change in mean pulmonary artery pressure (ΔmPAP) following TMVr on outcomes is unknown. METHODS: Patients who underwent TMVr from December 2015 to February 18, 2020 at our institution for symptomatic 3-4+ MR and who had invasive hemodynamics measured immediately pre- and post-TMVR were included. Multivariate Cox regression analysis was performed to examine the association of ΔmPAP (post-TMVr - pre-TMVr mPAP) with the primary endpoint of heart failure (HF) readmission at 1 year. Secondary endpoints included all-cause mortality and the composite endpoint of HF readmission or all-cause mortality at 1 year. RESULTS: Among 55 patients, 55% were men, mean age was 72 ± 14.2 years, and mean ΔmPAP was -1.4 ± 8.2 mm Hg. Overall, HF readmission occurred in 14 (25%), death in 10 (18%), and the composite endpoint in 20 (36%) patients. In multivariable analyses, higher ΔmPAP was significantly associated with HF readmission (hazard ratio (HR) = 1.10, 95% confidence interval (CI): 1.00 - 1.21; P = 0.04). ΔmPAP was not associated with death (HR = 1.04, 95% CI: 0.96 - 1.14; P = 0.33), though there was a numerical but statistically non-significant trend towards the composite endpoint (HR = 1.06, 95% CI: 1.00 - 1.13; P = 0.06) driven by HF readmission. CONCLUSION: Higher ΔmPAP immediately following TMVr was associated with increased HF readmission at 1 year. Larger prospective studies are needed to validate these data and further explore the utility of ΔmPAP as a novel hemodynamic parameter to predict post-TMVR outcomes.
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For conventional polycrystalline Ni-rich cathode material consisting of numerous primary particles in disordered orientation, the crystal anisotropy in charge/discharge process results in the poor rate capability and rapid capacity degradation. In this work, highly-dispersed submicron single-crystal LiNi0.8 Co0.15 Al0.05 O2 (SC-NCA) cathode is efficiently prepared by spray pyrolysis (SP) technique followed by a simple solid-state lithiation reaction. Porous Ni0.8 Co0.15 Al0.05 Ox precursor prepared via SP exhibits high chemical activity for lithiation reaction, enabling the fabrication of single-crystal cathode at a relatively low temperature. In this way, the contradiction between high crystallinity and cation disordering is well balanced. The resulted optimized SC-NCA shows polyhedral single-crystal morphology with moderate grain size (≈1 µm), which are beneficial to shortening the Li+ diffusion path and improving the structural stability. As cathode for lithium ion batteries, SC-NCA delivers a high discharge capacity of 202 and 140 mAh g-1 at 0.1 and 10 C, respectively, and maintains superior capacity retention of 161 mAh g-1 after 200 cycles at 1C. No micro-crack is observed in the cycled SC-NCA particles, indicating such single-crystal morphology can greatly relieve the anisotropic micro-strain. This effective, continuous and adaptable strategy for preparing single-crystal Ni-rich cathode without any additive may accelerate their practical application.
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Low-cost, scalable energy storage is the key to continuing growth of renewable energy technologies. Here a battery with sedimentary slurry electrode (SSE) is proposed. Through the conversion of discrete particles between sedimentary and suspending types, it not only inherits the advantages of semi-solid flow cell but also exhibits high energy density and stable conductive network. Given an example, the zinc SSE (ZSSE) delivers a large discharge capacity of 479.2 mAh g-1 at 10 mA cm-2. More importantly, by renewal of the slurry per 20 cycles, it can run for 112 and 75 cycles before falling below 80% of designed capacity under 10 mA cm-2 (20% DODZn) and 25 mA cm-2 (25% DODZn), respectively. The lost capacity after cycles is able to recover after slurry renewal and the end-of-life SSE can be easily reused by re-formation. The concept of SSE brands a new way for electrochemical energy storage.
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BACKGROUND: The effect of phase-change material blood containers on the quality of stored red blood cells (RBCs) transported in the Qinghai-Tibet Plateau remains to be studied. STUDY DESIGN AND METHODS: RBCs stored in a phase-change material blood container were transported from Chengdu to Tibet and then back to Chengdu. The detection time points were the 1st day of fresh-collected RBCs (group 1), the 14th day of resting refrigerated storage (group 2), and the 14th day of plateau transportation under refrigerated storage in the container (group 3). RBC counts, hemoglobin (HGB) content, free hemoglobin (FHb) content, blood biochemical indexes, hemorheologic indexes and 2,3-DPG content were detected. RESULTS: Compared with group 2, RBC counts and HGB were decreased, and the mean corpuscular volume (MCV), FHb and K+ content were increased in group 3. The glucose consumption and lactic acid production were significantly increased in groups 2 and 3. Compared with group 2, the 2,3-DPG content and whole blood viscosity were decreased in group 3. After resting refrigerated storage and plateau transportation, the RBC quality still met the national standard (GB18469-2012 whole blood and component blood quality requirements). CONCLUSION: The phase-change material blood container can be maintained at a constant temperature under plateau environmental conditions, ensuring that the quality of the stored RBCs is compliant with GB18469-2012 whole blood and component blood quality requirements.
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Preservação de Sangue/instrumentação , Eritrócitos/química , Manejo de Espécimes/instrumentação , Meios de Transporte , 2,3-Difosfoglicerato/sangue , Contagem de Eritrócitos , Glucose/metabolismo , Sistema Hematopoético/metabolismo , Hemoglobinas/metabolismo , Humanos , Ácido Láctico/sangue , TibetRESUMO
Novel triclinic LiV(PO4)0.9F1.3, characterized through its crystal lattice expansion, ultrafine primary particle size and uniform carbon coating, was designed and fabricated through regulating the PO4/F ratio. It exhibited excellent electrochemical performance, maintaining 105 mA h g-1 at 50C and 92.9% capacity retention after 500 cycles at 10C due to its superior structural stability, greater charge transfer properties, enhanced electronic conductivity and fast Li+ diffusion kinetics.
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Functional nanostructured materials have attracted great attention over the past several decades owing to their unique physical and chemical properties, while their applications have been proven to be advantageous not only in fundamental scientific areas, but also in many technological fields. Spray pyrolysis (SP), which is particularly facile, effective, highly scalable and suitable for on-line continuous production, offers significant potential for the rational design and synthesis of various functional nanostructured materials with tailorable composition and morphology. In this review, we summarize the recent progress in various functional nanostructured materials synthesized by SP and their potential applications in energy storage and conversion. After a brief introduction to the equipment, components, and working principles of the SP technique, we thoroughly describe the guidelines and strategies for designing particles with controlled morphology, composition, and interior architecture, including hollow structures, dense spheres, yolk-shell structures, core-shell structures, nanoplates, nanorods, nanowires, thin films, and various nanocomposites. Thereafter, we demonstrate their suitability for a wide range of energy storage and conversion applications, including electrode materials for rechargeable batteries, supercapacitors, highly active catalysts for hydrogen production, carbon dioxide reduction and fuel cells, and photoelectric materials for solar cells. Finally, the potential advantages and challenges of SP for the preparation of nanostructured materials are particularly emphasized and discussed, and several perspectives on future research and development directions of SP are highlighted. We expect that this continuous, one-pot, and controllable synthetic technology can serve as a reference for preparing various advanced functional materials for broader applications.
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A facile and large-scale fluidized bed reaction route was introduced for the first time to prepare crystalline embedded amorphous silicon nanoparticles with an average size of 50 nm as anode materials for lithium-ion batteries. By increasing the operating potential to control the electrochemically active degree, the resulting sample showed excellent cycle stability with a high capacity retention of 94.7% after 200 cycles at 1 A g-1 in the voltage range of 0.12-2.00 V.