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1.
J Pediatr Intensive Care ; 13(1): 80-86, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38571987

RESUMO

The aim of this study was to describe renal chloride metabolism following cardiopulmonary bypass (CPB) surgery in pediatric patients. A prospective observational trial in a tertiary pediatric intensive care unit (PICU) with 20 recruited patients younger than 2 years following CPB surgery was conducted. Urinary electrolytes, plasma urea, electrolytes, creatinine, and arterial blood gases were collected preoperatively, on admission to PICU and at standardized intervals thereafter. The urinary and plasma strong ion differences (SID) were calculated from these results at each time point. Fluid input and output and electrolyte and drug administration were also recorded. Median chloride administration was 67.7 mmol/kg over the first 24 hours. Urinary chloride (mmol/L; median interquartile range [IQR]) was 30 (19, 52) prior to surgery, 15 (15, 65) on admission, and remained below baseline until 24 hours. Plasma chloride (mmol/L; median [IQR]) was 105 (98, 107) prior to surgery and 101 (101, 106) on admission to PICU. It then increased from baseline, but remained within normal limits, for the remainder of the study. The urinary SID increased from 49.8 (19.1, 87.2) preoperatively to a maximum of 122.7 (92.5, 151.8) at 6 hours, and remained elevated until 48 hours. Plasma and urinary chloride concentrations were not associated with the development of acute kidney injury. Urinary chloride excretion is impaired after CPB. The urinary SID increase associated with the decrease in chloride excretion suggests impaired production and/or excretion of ammonium by the nephron following CPB, with gradual recovery postoperatively.

2.
Adv Mater ; : e2314120, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578406

RESUMO

Solid polymer electrolytes (SPEs) for lithium metal batteries have garnered considerable interests owing to their low cost, flexibility, lightweight, and favorable interfacial compatibility with battery electrodes. Their soft mechanical nature compared to solid inorganic electrolytes give them a large advantage to be used in low pressure solid-state lithium metal batteries (SSLMBs), which can avoid the cost and weight of the pressure cages. However, the application of SPEs has been hindered by their relatively low ionic conductivity. In addressing this limitation, enormous efforts have been devoted to the experimental investigation and theoretical calculations/simulation of new polymer classes. Recently, metal-organic frameworks (MOFs) have been shown to be effective in enhancing ion transport in SPEs. However, the mechanisms in enhancing Li+ conductivity have rarely been systematically and comprehensively analyzed. Therefore, this review provides an in-depth summary of the mechanisms of MOF-enhanced Li+ transport in MSPEs in terms of polymer, MOF, MOF/polymer interface (MPI) and solid electrolyte interface (SEI) aspects, respectively. Moreover, the understanding of Li+ conduction mechanisms through employing advanced characterization tools, theoretical calculations and simulations are also reviewed in this review. Finally, the main challenges in developing MSPEs are deeply analyzed and the corresponding future research directions are also proposed. This article is protected by copyright. All rights reserved.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38600661

RESUMO

High-voltage resistant quasi-solid-state polymer electrolytes (QSPEs) are promising for enhancing the energy density of lithium-metal batteries in practice. However, side reactions occurring at the interfaces between the anodes or cathodes and QSPEs considerably reduce the lifespan of high-voltage LMBs. In this study, a copolymer of vinyl ethylene carbonate (VEC) and poly(ethylene glycol) diacrylate (PEGDA) was used as the framework, with a cellulose membrane (CE) as the supporting layer. Based on density functional theory calculations, 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI), an ionic liquid, was screened because of its lowest unoccupied molecular orbital energy level as a modifying agent for the in situ P(VECx-EGy)/Pyrz/LiTFSI@CE QSPEs synthesis. Pyr14+, with a lithiophobic alkyl chain, forms a dense positive ion shielding layer on the protruding tips of deposited lithium, facilitating uniform and smooth lithium deposition. Pyr14TFSI assists in constructing a stable solid electrolyte interphase (SEI) layer on the Li surface enriched with LiF, Li3N, and RCOOLi. The modulation of lithium deposition behavior on the anode by Pyr14TFSI ensures stable Li plating/stripping for >1500 h. A Li-Cu cell exhibits stable cycling for >200 cycles at a current density of 0.05 mA cm-2, with an average Coulombic efficiency of 92.7%. In situ polymerization ensures that P(VECx-EGy)/Pyrz/LiTFSI@CE QSPEs exhibit excellent interface compatibility with the anode and the cathode. The CR2032 button cell Li|P(VEC1-EG0.06)/Pyr0.4/LiTFSI@CE|LiCoO2 demonstrates stable cycling with a negligible capacity decay of 0.083% per cycle for >390 cycles at 25 °C and 0.2 C when using a high-voltage LiCoO2 (4.45 V) cathode. Furthermore, a 7.1 mAh pouch cell achieves stable charge-discharge cycles, confirming the pronounced stability of the as-fabricated QSPE at the interfaces of the high-voltage LiCoO2 cathode and Li anode.

4.
Nano Lett ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592099

RESUMO

The nature of ion-ion interactions in electrolytes confined to nanoscale pores has important implications for energy storage and separation technologies. However, the physical effects dictating the structure of nanoconfined electrolytes remain debated. Here we employ machine-learning-based molecular dynamics simulations to investigate ion-ion interactions with density functional theory level accuracy in a prototypical confined electrolyte, aqueous NaCl within graphene slit pores. We find that the free energy of ion pairing in highly confined electrolytes deviates substantially from that in bulk solutions, observing a decrease in contact ion pairing but an increase in solvent-separated ion pairing. These changes arise from an interplay of ion solvation effects and graphene's electronic structure. Notably, the behavior observed from our first-principles-level simulations is not reproduced even qualitatively with the classical force fields conventionally used to model these systems. The insight provided in this work opens new avenues for predicting and controlling the structure of nanoconfined electrolytes.

5.
Pan Afr Med J ; 47: 37, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586073

RESUMO

Introduction: type 2 Diabetes mellitus is a chronic metabolic disease with devastating effects on patients and results in numerous healthcare challenges in terms of its management and the cost burden among the affected. Successful management involves maintaining optimal glycemic control to prevent complications, with adherence to antidiabetic medications playing a crucial role in achieving this objective. Additionally, maintaining a healthy electrolyte balance is key for overall well-being and physiological function. However, the correlation between glycated hemoglobin and electrolyte balance remains under investigated, particularly in patients with suboptimal adherence. The aim of this research was to study the relationship between glycated hemoglobin and electrolytes among diabetic patients with poor adherence to antidiabetic medications. Methods: this study was conducted at Samburu County Referral Hospital in Samburu County, Kenya. We employed a descriptive cross-sectional design focusing on adult diabetic patients aged 18 years and above who had visited the diabetic clinic over a three-month period. To evaluate their adherence levels, we employed a Morisky Medication Adherence Scale-8. Seventy-two diabetic patients who got adherence level scores of < 6 were categorized as having low adherence and their blood samples were collected for measuring glycated hemoglobin levels and electrolytes levels particularly potassium, sodium, calcium, magnesium, phosphorus and chloride. Relationship between electrolytes and glycated hemoglobin among diabetic patients with poor adherence to antidiabetics was determined using Karl Pearson correlation. Results: among the study participants, the lowest hemoglobin A1C (HbA1c) level recorded was 5.1% while the highest was 15.0% and the majority (41.7%) fell within the HbA1c range of 5-7%. A high proportion of individuals (58.3%) with poor adherence to antidiabetics had elevated HbA1c levels, indicating poor glycemic control. The correlations observed between glycated hemoglobin and electrolytes which included magnesium, sodium, chloride, calcium and phosphorus was r= -0.07, -0.32, -0.05 -0.24 and -0.04 respectively. Conclusion: this study concluded that there is a relationship between electrolytes and glycated hemoglobin among diabetic patients with poor adherence to antidiabetics. A statistically significant negative correlation was observed between glycated hemoglobin and calcium level (r=-0.2398 P ≤0.05) and also sodium (r=-0.31369 P≤0.05). A negative correlation (P≥0.05) was observed between phosphorus, magnesium, chloride and potassium with HbA1c levels though not statistically significant.


Assuntos
Diabetes Mellitus Tipo 2 , Adulto , Humanos , Hemoglobinas Glicadas , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Estudos Transversais , Cálcio , Magnésio , Cloretos/uso terapêutico , Glicemia/metabolismo , Hipoglicemiantes/uso terapêutico , Eletrólitos , Sódio , Potássio , Fósforo
6.
Angew Chem Int Ed Engl ; : e202400091, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644754

RESUMO

Poly(ethylene oxide) (PEO)-based composite solid electrolytes (CSEs) are promising to accelerate commercialization of solid-state lithium metal batteries (SSLMBs). Nonetheless, this is hindered by the CSEs' limited ion conductivity at room temperature. Here, we propose design, synthesis, and application of the bioinspired neuron-like nanofillers for PEO-based CSEs. The neuron-like superhydrophobic nanofillers are synthesized by controllably grafting silicone nanofilaments onto montmorillonite nanosheets. Compared to various reported fillers, the nanofillers can greatly improve ionic conductivity (4.9 × 10-4 S cm-1, 30 °C), Li+ transference number (0.63), oxidation stability (5.3 V) and mechanical properties of the PEO-based CSEs because of the following facts. The distinctive neuron-like structure and the resulting synaptic-like connections establish numerous long-distance continuous channels over various directions in the PEO-based CSEs for fast and uniform Li+ transport. Consequently, the assembled SSLMBs with the CSEs and LiFePO4 or NCM811 cathodes display superior cycling stability over a wide temperature range of 50 °C to 0 °C. Surprisingly, the pouch batteries with the large-scale prepared CSEs kept working after being repeatedly bent, folded, cut or even punched in air. We believe that design of neuron-like nanofillers is a viable approach to produce CSEs with high room temperature ionic conductivity for SSLMBs.

7.
Adv Sci (Weinh) ; : e2402343, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572506

RESUMO

Rechargeable Zn-air batteries (ZABs) are considered highly competitive technologies for meeting the energy demands of the next generation, whether for energy storage or portable power. However, their practical application is hindered by critical challenges such as low voltage, CO2 poisoning at the cathode, low power density, and poor charging efficiency Herein, a rechargeable hybrid alkali/acid Zn-air battery (h-RZAB) that effectively separates the discharge process in an acidic environment from the charging process in an alkaline environment, utilizing oxygen reduction reaction (ORR) and glycerol oxidation reaction (GOR) respectively is reported. Compared to previously reported ZABs, this proof-of-concept device demonstrates impressive performance, exhibiting a high power density of 562.7 mW cm-2 and a high operating voltage during discharging. Moreover, the battery requires a significantly reduced charging voltage due to the concurrent utilization of biomass-derived glycerol, resulting in practical and cost-effective advantages. The decoupled system offers great flexibility for intermittently generated renewable power sources and presents cost advantages over traditional ZABs. As a result, this technology holds significant promise in opening avenues for the future development of renewable energy-compatible electrochemical devices.

8.
Adv Sci (Weinh) ; : e2310005, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572525

RESUMO

Inferior air stability is a primary barrier for large-scale applications of garnet electrolytes in energy storage systems. Herein, a deeply hydrated hydrogarnet electrolyte generated by a simple ion-exchange-induced phase transition from conventional garnet, realizing a record-long air stability of more than two years when exposed to ambient air is proposed. Benefited from the elimination of air-sensitive lithium ions at 96 h/48e sites and unobstructed lithium conduction path along tetragonal sites (12a) and vacancies (12b), the hydrogarnet electrolyte exhibits intrinsic air stability and comparable ion conductivity to that of traditional garnet. Moreover, the unique properties of hydrogarnet pave the way for a brand-new aqueous route to prepare lithium metal stable composite electrolyte on a large-scale, with high ionic conductivity (8.04 × 10-4 S cm-1), wide electrochemical windows (4.95 V), and a high lithium transference number (0.43). When applied in solid-state lithium batteries (SSLBs), the batteries present impressive capacity and cycle life (164 mAh g-1 with capacity retention of 89.6% after 180 cycles at 1.0C under 50 °C). This work not only designs a new sort of hydrogarnet electrolyte, which is stable to both air and lithium metal but also provides an eco-friendly and large-scale fabrication route for SSLBs.

9.
Angew Chem Int Ed Engl ; : e202403050, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579168

RESUMO

Unstable Zn interface with serious detrimental parasitic side-reactions and uncontrollable Zn dendrites severely plagues the practical application of aqueous zinc-ion batteries. The interface stability was closely related to the electrolyte configuration and Zn2+ depositional behavior. In this work, a unique Zn-ion anchoring strategy is originally proposed to manipulate the coordination structure of solvated Zn-ions and guide the Zn-ion depositional behavior. Specifically, the amphoteric charged ion additives (denoted as DM), which act as zinc-ion anchors, can tightly absorb on the Zn surface to guide the uniform zinc-ion distribution by using its positively charged -NR4+ groups. While the negatively charged -SO3- groups of DM on the other hand, reduces the active water molecules within solvation sheaths of Zn-ions. Benefiting from the special synergistic effect, Zn metal exhibits highly ordered and compact (002) Zn deposition and negligible side-reactions. As a result, the advanced Zn||Zn symmetric cell delivers extraordinarily 7000 hours long lifespan (0.25 mAh cm-2, 0.25 mAh cm-2). Additionally, based on this strategy, the NH4V4O10llZn pouch-cell with low negative/positive capacity ratio (N/P ratio=2.98) maintains 80.4% capacity retention for 180 cycles. A more practical 4 cm*4 cm sized pouch-cell could be steadily cycled in a high output capacity of 37.0 mAh over 50 cycles.

10.
Nanomicro Lett ; 16(1): 172, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619762

RESUMO

Solid-state batteries are commonly acknowledged as the forthcoming evolution in energy storage technologies. Recent development progress for these rechargeable batteries has notably accelerated their trajectory toward achieving commercial feasibility. In particular, all-solid-state lithium-sulfur batteries (ASSLSBs) that rely on lithium-sulfur reversible redox processes exhibit immense potential as an energy storage system, surpassing conventional lithium-ion batteries. This can be attributed predominantly to their exceptional energy density, extended operational lifespan, and heightened safety attributes. Despite these advantages, the adoption of ASSLSBs in the commercial sector has been sluggish. To expedite research and development in this particular area, this article provides a thorough review of the current state of ASSLSBs. We delve into an in-depth analysis of the rationale behind transitioning to ASSLSBs, explore the fundamental scientific principles involved, and provide a comprehensive evaluation of the main challenges faced by ASSLSBs. We suggest that future research in this field should prioritize plummeting the presence of inactive substances, adopting electrodes with optimum performance, minimizing interfacial resistance, and designing a scalable fabrication approach to facilitate the commercialization of ASSLSBs.

11.
Adv Mater ; : e2400970, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623832

RESUMO

The lignin derived ultrathin all-solid composite polymer electrolyte (CPE) with a thickness of only 13.2 µm, which possess 3D nanofiber ionic bridge networks composed of single-ion lignin-based lithium salt (L-Li) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) as the framework, and poly(ethylene oxide)/lithium bis(trifluoromethanesulfonyl)imide (PEO/LiTFSI) as the filler, is obtained through electrospinning/spraying and hot-pressing. t. The Li-symmetric cell assembled with the CPE can stably cycle more than 6000 h under 0.5 mA cm-2 with little Li dendrites growth. Moreover, the assembled Li||CPE||LiFePO4 cells can stably cycle over 700 cycles at 0.2 C with a super high initial discharge capacity of 158.5 mAh g-1 at room temperature, and a favorable capacity of 123 mAh g-1 at -20 °C for 250 cycles. The excellent electrochemical performance is mainly attributed to the reason that the nanofiber ionic bridge network can afford uniformly dispersed single-ion L-Li through electrospinning, which synergizes with the LiTFSI well dispersed in PEO to form abundant and efficient 3D Li+ transfer channels. The ultrathin CPE induces uniform deposition of Li+ at the interface, and effectively inhibit the lithium dendrites. This work provides a promising strategy to achieve ultrathin biobased electrolytes for solid-state lithium ion batteries.

12.
Angew Chem Int Ed Engl ; : e202400032, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653713

RESUMO

Gel-state polymer electrolytes with superior mechanical properties, self-healing abilities and high Li+ transference numbers can be obtained by in situ polymerization of monomers with hydrogen-bonding moieties. However, it is overlooked that the active hydrogen atoms in hydrogen-bond donors experience displacement reactions with lithium metal in lithium metal batteries (LMBs), leading to corrosion of the lithium metal. Herein, it is discovered that the addition of hydrogen-bond acceptors to hydrogen-bond-rich gel-state electrolytes modulates the chemical activity of the active hydrogen atoms via the formation of hydrogen-bonded intermolecular interactions. The characterizations reveal that the added hydrogen-bond acceptors encapsulate the active hydrogen atoms to suppress the interfacial chemical corrosions of lithium metals, thereby enhancing the chemical stability of the polymer structure and interphase. With the employment of this strategy, a 1.1 Ah LiNi0.8Co0.1Mn0.1O2/Li metal pouch cell achieves stable cycling with 96.3% capacity retention at 100 cycles. This new approach indicates a feasible path for achieving in situ polymerization of highly stable gel-state-based LMBs.

13.
Adv Mater ; : e2401284, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38574258

RESUMO

The development of solid-state electrolytes (SSEs) with outstanding comprehensive performance is currently a critical challenge for achieving high energy density and safer solid-state batteries (SSBs). In this study, a strategy of nano-confined in situ solidification is proposed to create a novel category of molten guest-mediated metal-organic frameworks, named MGM-MOFs. By embedding the newly developed molten crystalline organic electrolyte (ML20) into the nanocages of anionic MOF-OH, MGM-MOF-OH, characterized by multi-modal supramolecular interaction sites and continuous negative electrostatic environments within nano-channels, is achieved. These nanochannels promote ion transport through the successive hopping of Li+ between neighbored negative electrostatic environments and suppress anion movement through the chemical constraint of the hydroxyl-functionalized pore wall. This results in remarkable Li+ conductivity of 7.1 × 10-4 S cm-1 and high Li+ transference number of 0.81. Leveraging these advantages, the SSBs assembled with MGM-MOF-OH exhibit impressive cycle stability and a high specific energy density of 410.5 Wh kganode + cathode + electrolyte -1 under constrained conditions and various working temperatures. Unlike flammable traditional MOFs, MGM-MOF-OH demonstrates high robustness under various harsh conditions, including ignition, high voltage, and extended to humidity.

14.
Adv Mater ; : e2401486, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607186

RESUMO

Aqueous electrolytes and related aqueous rechargeable batteries own unique advantage on safety and environmental friendliness, but coupling high energy density Li-metal batteries with aqueous electrolyte still represent challenging and not yet reported. Here, this work makes a breakthrough in "high-voltage aqueous Li-metal batteries" (HVALMBs) by adopting a brilliant hybrid-electrolytes strategy. Concentrated ternary-salts ether-based electrolyte (CTE) acts as the anolyte to ensure the stability and reversibility of Li-metal plating/stripping. Eco-friendly water-in-salt (WiS) electrolyte acts as catholyte to support the healthy operation of high-voltage cathodes. Most importantly, the aqueous catholyte and non-aqueous anolyte are isolated in each independent chamber without any crosstalk. Aqueous catholyte permeation toward Li anode can be completely prohibited without proton-induced corrosion, which is enabled by the introduction of under-liquid dual super-lyophobic membrane-based separator, which can realize the segregation of the most effective immiscible electrolytes with a surface tension difference as small as 6 mJ m-2. As a result, the aqueous electrolyte can be successfully coupled with Li-metal anode and achieve the fabrication of HVALMBs (hybrid-electrolytes system), which presents long-term cycle stability with a capacity retention of 81.0% after 300 cycles (LiNi0.8Mn0.1Co0.1O2 || Li (limited) cell) and high energy density (682 Wh kg-1).

15.
Nanotechnology ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640910

RESUMO

Lithium-ion batteries (LIBs) has extensively utilized in electric vehicles and portable electronics due to their high energy density and prolonged lifespan. However, the current commercial LIBs are plagued by relatively low energy density. High-entropy materials with multiple components have emerged as an efficient strategic approach for developing novel materials that effectively improve the overall performance of LIBs. This article provides a comprehensive review the recent advancements in rational design of innovative high-entropy materials for LIBs, as well as the exceptional lithium ion storage mechanism for high-entropy electrodes and considerable ionic conductivity for high-entropy electrolytes. This review also analyses the prominent effects of individual components on the high-entropy materials' exceptional capacity, considerable structural stability, rapid lithium ion diffusion, and excellent ionic conductivity. Furthermore, this review presents the synthesis methods and their influence on the morphology and properties of high-entropy materials. Ultimately, the remaining challenges and future research directions are outlined, aimed at developing more effective high-entropy materials and improving the overall electrochemical performance of LIBs. .

16.
Adv Sci (Weinh) ; : e2401739, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641888

RESUMO

This review article discusses the hidden or often overlooked negative issues of large-capacity cathodes, high-voltage systems, concentrated electrolytes, and reversible lithium metal electrodes in high-energy-density lithium batteries and provides some feasible solutions that can realize the construction of realistic rechargeable batteries with higher energy densities. Similar objective discussion of the negative aspects of lithium-air batteries, multi-valent shuttles, anion shuttles, sulfur cathode systems, and all-solid ceramic batteries can help fabricate more realistic batteries.

17.
Carbohydr Polym ; 335: 122075, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616096

RESUMO

Polyethylene oxide (PEO) solid electrolytes, acknowledged for their safety advantages over liquid counterparts, confront inherent challenges, including low ionic conductivity, restricted lithium ion migration, and mechanical fragility, notably pronounced in lithium­sulfur batteries due to the polysulfide shuttling phenomenon. To address these limitations, we integrate a quaternary ammonium cation-modified cellulose (QACC) nanofiber, electrospun with cellulose acetate (CA) from recycled cigarette filters, into the PEO electrolyte matrix. The nitrogen atom within the quaternary ammonium group exhibits a pronounced affinity for polysulfide compounds, effectively curtailing polysulfide migration. Concurrently, Lewis acid-base interactions between quaternary ammonium groups and lithium salt anions facilitate the release of additional Li+, achieving a lithium-ion transference number 1.5 times higher than its pure PEO counterpart. Furthermore, the introduction of a larger trifluoromethanesulfonimide (TFSI) group on the QACC macromolecule (TFSI-QACC) disrupts the ordered arrangement of PEO macromolecules, resulting in a noteworthy enhancement in ionic conductivity, reaching 2.07 × 10-4 S cm-1 at 60 °C, thus addressing the challenge of low PEO electrolyte conductivity. Moreover, the nanofiber enhances the mechanical strength of the PEO electrolyte from 0.49 to 7.50 MPa, mitigating safety concerns related to lithium dendrites puncturing the electrolyte. Consequently, the composite PEO demonstrates exemplary performance in lithium symmetrical batteries, enduring 500 h of continuous operation and completing 100 cycles at both room and elevated temperatures. This integrated approach, transitioning from waste to wealth, adeptly addresses a spectrum of challenges in the efficiency of solid-state electrolytes, holding considerable promise for advancing lithium­sulfur battery technology.

18.
Small ; : e2309735, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618655

RESUMO

Solid oxide fuel cells (SOFCs) are paving the way to clean energy conversion, relying on efficient oxygen-ion conductors with high ionic conductivity coupled with a negligible electronic contribution. Doped rare earth aluminates are promising candidates for SOFC electrolytes due to their high ionic conductivity. However, they often suffer from p-type electronic conductivity at operating temperatures above 500 °C under oxidizing conditions caused by the incorporation of oxygen into the lattice. High entropy materials are a new class of materials conceptualized to be stable at higher temperatures due to their high configurational entropy. Introducing this concept to rare earth aluminates can be a promising approach to stabilize the lattice by shifting the stoichiometric point of the oxides to higher oxygen activities, and thereby, reducing the p-type electronic conductivity in the relevant oxygen partial pressure range. In this study, the high entropy oxide (Gd,La,Nd,Pr,Sm)AlO3 is synthesized and doped with Ca. The Ca-doped (Gd,La,Nd,Pr,Sm)AlO3 compounds exhibit a higher ionic conductivity than most of the corresponding Ca-doped rare earth aluminates accompanied by a reduction of the p-type electronic conductivity contribution typically observed under oxidizing conditions. In light of these findings, this study introduces high entropy aluminates as a promising candidate for SOFC electrolytes.

19.
Small ; : e2402086, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607305

RESUMO

Lithophobic Li2CO3/LiOH contaminants and high-resistance lithium-deficient phases produced from the exposure of garnet electrolyte to air leads to a decrease in electrolyte ion transfer ability. Additionally, garnet electrolyte grain boundaries (GBs) with narrow bandgap and high electron conductivity are potential channels for current leakage, which accelerate Li dendrites generation, ultimately leading to short-circuiting of all-solid-state batteries (ASSBs). Herein, a stably lithiophilic Li2ZO3 is in situ constructed at garnet electrolyte surface and GBs by interfacial modification with ZrO2 and Li2CO3 (Z+C) co-sintering to eliminate the detrimental contaminants and lithium-deficient phases. The Li2ZO3 formed on the modified electrolyte (LLZTO-(Z+C)) surface effectively improves the interfacial compatibility and air stability of the electrolyte. Li2ZO3 formed at GBs broadens the energy bandgaps of LLZTO-(Z+C) and significantly inhibits lithium dendrite generation. More Li+ transport paths found in LLZTO-Z+C by first-principles calculations increase Li+ conductivity from 1.04×10-4 to 7.45×10-4 S cm-1. Eventually, the Li|LLZTO-(Z+C)|Li symmetric cell maintains stable cycling for over 2000 h at 0.8 mA cm-2. The capacity retention of LiFePO4|LLZTO-(Z+C)|Li battery retains 70.5% after 5800 ultralong cycles at 4 C. This work provides a potential solution to simultaneously enhance the air stability and modulate chemical characteristics of the garnet electrolyte surface and GBs for ASSBs.

20.
ACS Appl Mater Interfaces ; 16(15): 19014-19025, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38573769

RESUMO

Rechargeable magnesium batteries (RMBs) are one of the most promising "post-lithium" battery technologies, but the electrochemical performance is still far from expectation due to the sluggish reaction kinetics of divalent Mg2+ ions. Herein, we report a low-cost, high-performance Mg-organic battery based on the combination of a fluorinated alkoxyaluminate electrolyte and a carbonyl polymer cathode material. First, the one-pot synthesized Mg[Al(HFIP)4]2 (HFIP = hexafluoro-2-propanol) is proved superior to the Mg[B(HFIP)4]2 analogue in both Mg anode compatibility and electrochemical window, as the electrolyte salt in the G2-DME (G2 = diethylene glycol dimethyl ether; DME = 1,2-dimethoxyethane) mixture solvent. Second, a simple wet grinding method is proposed to effectively improve the dispersion uniformity of the poly(benzoquinone-pyrrole) (PBQPy) active material in the cathode. Third, the elaborate Mg-PBQPy battery exhibits superior electrochemical performance within 0.4-3.0 V, including a high reversible capacity of 197 mA h g-1, a high average discharge voltage of 1.6 V, and a high capacity retention of 71% after 500 cycles. Finally, based on various electrochemical analysis and ex situ characterization results, we propose a general microscopic structure evolution model to reveal the electrochemical behaviors of carbonyl polymer cathode in RMBs, including the swelling of polymer active material, trapping of Mg2+ ions, and reversible redox reaction.

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