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1.
Sensors (Basel) ; 24(12)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38931568

RESUMO

Accurate determination of the number and location of immature small yellow peaches is crucial for bagging, thinning, and estimating yield in modern orchards. However, traditional methods have faced challenges in accurately distinguishing immature yellow peaches due to their resemblance to leaves and susceptibility to variations in shooting angles and distance. To address these issues, we proposed an improved target-detection model (EMA-YOLO) based on YOLOv8. Firstly, the sample space was enhanced algorithmically to improve the diversity of samples. Secondly, an EMA attention-mechanism module was introduced to encode global information; this module could further aggregate pixel-level features through dimensional interaction and strengthen small-target-detection capability by incorporating a 160 × 160 detection head. Finally, EIoU was utilized as a loss function to reduce the incidence of missed detections and false detections of the target small yellow peaches under the condition of high density of yellow peaches. Experimental results show that compared with the original YOLOv8n model, the EMA-YOLO model improves mAP by 4.2%, Furthermore, compared with SDD, Objectbox, YOLOv5n, and YOLOv7n, this model's mAP was improved by 30.1%, 14.2%,15.6%, and 7.2%, respectively. In addition, the EMA-YOLO model achieved good results under different conditions of illumination and shooting distance and significantly reduced the number of missed detections. Therefore, this method can provide technical support for smart management of yellow-peach orchards.

2.
Angew Chem Int Ed Engl ; 63(28): e202403607, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38659136

RESUMO

Alkaline zinc-ferricyanide flow batteries are efficiency and economical as energy storage solutions. However, they suffer from low energy density and short calendar life. The strongly alkaline conditions (3 mol L-1 OH-) reduce the solubility of ferri/ferro-cyanide (normally only 0.4 mol L-1 at 25 °C) and induce the formation of zinc dendrites at the anode. Here, we report a new zinc-ferricyanide flow battery based on a mild alkalescent (pH 12) electrolyte. Using a chelating agent to rearrange ferri/ferro-cyanide ion-solvent interactions and improve salt dissociation, we increased the solubility of ferri/ferro-cyanide to 1.7 mol L-1 and prevented zinc dendrites. Our battery has an energy density of ~74 Wh L-1 catholyte at 60 °C and remains stable for 1800 cycles (1800 hours) at 0 °C and for >1400 cycles (2300 hours) at 25 °C. An alkalescent zinc-ferricyanide cell stack built using this alkalescent electrolyte stably delivers 608 W of power for ~40 days.

3.
Adv Mater ; 35(7): e2209390, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36444512

RESUMO

Achieving net-zero emissions requires low-cost and reliable energy storage devices that are essential to deploy renewables. Alkaline zinc-based flow batteries such as alkaline zinc-iron (or nickel) flow batteries are well suited for energy storage because of their high safety, high efficiency, and low cost. Nevertheless, their energy density is limited by the low solubility of ferro/ferricyanide and the limited areal capacity of sintered nickel electrodes. Here, combining the electrochemical reaction with the chemical reaction of ferro/ferricyanide couple in a homemade nickel electrode, an alkaline zinc-iron/nickel hybrid flow battery with a high energy density of 208.9 Wh L-1 and an energy efficiency of 84.7% at a high current density of 80 mA cm-2 is reported. The reversible chemical reactions between dual couples are proven to stabilize the nickel electrode by promoting the activation of the nickel electrode and further preventing the formation of γ-NiOOH. A kW-scale stack is demonstrated by the integration of ferro/ferricyanide couple with nickel electrode, delivering a coulombic efficiency of 98% and an energy efficiency of 89% at 40 mA cm-2 . This work demonstrates a promising pathway for constructing and upscaling flow batteries with high energy density and low cost.

4.
Innovation (Camb) ; 2(4): 100180, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34877561

RESUMO

Global development has been heavily reliant on the overexploitation of natural resources since the Industrial Revolution. With the extensive use of fossil fuels, deforestation, and other forms of land-use change, anthropogenic activities have contributed to the ever-increasing concentrations of greenhouse gases (GHGs) in the atmosphere, causing global climate change. In response to the worsening global climate change, achieving carbon neutrality by 2050 is the most pressing task on the planet. To this end, it is of utmost importance and a significant challenge to reform the current production systems to reduce GHG emissions and promote the capture of CO2 from the atmosphere. Herein, we review innovative technologies that offer solutions achieving carbon (C) neutrality and sustainable development, including those for renewable energy production, food system transformation, waste valorization, C sink conservation, and C-negative manufacturing. The wealth of knowledge disseminated in this review could inspire the global community and drive the further development of innovative technologies to mitigate climate change and sustainably support human activities.

5.
Phys Chem Chem Phys ; 23(46): 26070-26084, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34787128

RESUMO

Zinc-bromine batteries (ZBBs) receive wide attention in distributed energy storage because of the advantages of high theoretical energy density and low cost. However, their large-scale application is still confronted with some obstacles. Therefore, in-depth research and advancement on the structure, electrolyte, anode, cathode and membrane are of great significance and impendency. Herein, we review the past and present investigations on ZBBs, discuss the key problems and technical challenges, and propose perspectives for the future, with the focus on materials and chemistry. This perspective would provide valuable information on further development of ZBBs.

6.
J Am Chem Soc ; 143(33): 13135-13144, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34313429

RESUMO

Zinc-based batteries are promising for use as energy storage devices owing to their low cost and high energy density. However, zinc chemistry commonly encounters serious dendrite issues, especially at high areal capacities and current densities, limiting their application. Herein, we propose a novel membrane featuring ordered undulating stripes called "Turing patterns", which can effectively suppress zinc dendrites and improve ion conductivity. The crests and troughs in the Turing membrane can effectively adjust the Zn(OH)42- distribution and provide more zinc deposition space. The coordinated Cu ions during membrane formation can interact with Zn(OH)42-, further smoothing zinc deposition. Even at a high current density of 80 mA·cm-2, the Turing membrane enables an alkaline zinc-iron flow battery (AZIFB) to work stably with an ultrahigh areal capacity of 160 mA·h·cm-2 for approximately 110 cycles, showing an energy efficiency of 90.10%, which is by far the highest value ever reported among zinc-based batteries with such a high current density. This paper provides valid access to zinc-based batteries with high areal capacities based on membrane design and promotes their advancement.

7.
Nat Commun ; 12(1): 3409, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099700

RESUMO

Membranes with fast and selective ions transport are highly demanded for energy storage devices. Layered double hydroxides (LDHs), bearing uniform interlayer galleries and abundant hydroxyl groups covalently bonded within two-dimensional (2D) host layers, make them superb candidates for high-performance membranes. However, related research on LDHs for ions separation is quite rare, especially the deep-going study on ions transport behavior in LDHs. Here, we report a LDHs-based composite membrane with fast and selective ions transport for flow battery application. The hydroxide ions transport through LDHs via vehicular (standard diffusion) & Grotthuss (proton hopping) mechanisms is uncovered. The LDHs-based membrane enables an alkaline zinc-based flow battery to operate at 200 mA cm-2, along with an energy efficiency of 82.36% for 400 cycles. This study offers an in-depth understanding of ions transport in LDHs and further inspires their applications in other energy-related devices.

8.
ACS Appl Mater Interfaces ; 12(46): 51573-51580, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33156620

RESUMO

Alkaline zinc-iron flow batteries (AZIFBs) are a very promising candidate for electrochemical energy storage. The electrolyte plays an important role in determining the energy density and reliability of a battery. The substantial water migration through a membrane during cycling is one of the critical issues that affect the reliability and performance of an AZIFB. In this work, it has been proven that the reason for water migration in AZIFBs is the synergetic effect of concentration gradient, different ionic strengths of negolyte and posolyte, and the electric field. To address the issue of water migration in AZIFBs, a series of additives are employed and the effects of additives on the water transfer behavior and electrochemical performance of AZIFBs are investigated in detail. The results indicate that all investigated additives can suppress water migration through a polybenzimidazole membrane because of the shrunken gap of osmotic pressure and ionic strength between negolyte and posolyte. Moreover, organic additives such as glucose can decrease battery performance because of the increased polarizability of the electrode, whereas inorganic additives such as Na2SO4 demonstrate no distinct effect on battery performance. Specifically, an AZIFB that employs Na2SO4 as an additive in the negative electrolyte can afford a Coulombic efficiency of ∼99% and a voltage efficiency of ∼88% for 120 cycles at 80 mA cm-2, together with a good effect for inhibiting water migration behavior. This paper presents an effective way to suppress water migration and increase the reliability of AZIFBs.

9.
ACS Appl Mater Interfaces ; 12(43): 48533-48541, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33063988

RESUMO

Aqueous organic-based flow batteries are increasingly receiving attention owing to their appealing traits of high safety and low cost. An economic and high-performance membrane is always regarded as the heart of the batteries. Here, we introduce a cost-effective, homemade porous membrane with high performance for alkaline quinone-based flow batteries. The membrane is constituted by highly stable poly(ether sulfone) (PES) and sulfonated poly(ether ether ketone) (SPEEK) that serves dual functions of (1) adjusting the membrane microstructure and (2) endowing the membrane with a charge trait. Benefiting from the well-tuned structure and charge property of the membrane, a high ion selectivity and transport of OH- with much higher mobility serving as the primary charge-balancing ion can be realized. By employing alkaline alizarin red (ARS)/ferro-ferricyanide flow battery as the platform, a battery delivers a coulombic efficiency (CE) of 98.28% and an energy efficiency (EE) of 85.81% at 40 mA cm-2, which is higher than that of the battery with a Nafion 212 membrane (CE ∼ 99.19%, EE ∼ 84.60%), however, with much lower cost. The successful application of homemade porous membrane may provide a new strategy to engineer and fabricate membranes with high efficiency for alkaline quinone-based flow batteries and further decrease the batteries' cost.

10.
Angew Chem Int Ed Engl ; 59(17): 6715-6719, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32022372

RESUMO

The capability to maintain a constant system temperature is vital in nature, since it endows the system with enhanced lifetime. This trait also works for zinc-based batteries, because their cycle-life is limited by notorious zinc dendrite/accumulation, which are highly affected by the inhomogeneous distribution of temperature on electrode and relatively low mechanical strength of membrane. Herein, boron nitride nanosheets (BNNSs) with high mechanical strength serving as heat-porter are introduced onto a porous substrate to enable uniform deposition of zinc and further a zinc-based flow battery with long-cycle life. The results indicate that BNNSs can effectively adjust the deposited zinc from needle-like to French fries-like morphology, thus affording the battery with a stable performance for nearly 500 cycles at 80 mA cm-2 . Most importantly, an energy efficiency of above 80 % can be obtained even at 200 mA cm-2 , which is by far the highest value ever reported among zinc-based flow batteries.

11.
Adv Mater ; 31(50): e1902025, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31475411

RESUMO

Zinc-based flow batteries (ZFBs) are well suitable for stationary energy storage applications because of their high energy density and low-cost advantages. Nevertheless, their wide application is still confronted with challenges, which are mainly from advanced materials. Therefore, research on advanced materials for ZFBs in terms of electrodes, membranes, and electrolytes as well as their chemistries are of the utmost importance. Herein, the focus is on the scientific understandings of the fundamental design of these advanced materials and their chemistries in relation to the battery performance. The principles of using different materials in different ZFB technologies, the functions and structure of the materials, and further material improvements are discussed in detail. Finally, the challenges and prospects of ZFBs are summarized as well. This review provides valuable instruction on how to design and develop new materials as well as new chemistries for ZFBs.

12.
iScience ; 3: 40-49, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-30428329

RESUMO

Alkaline zinc-iron flow battery is a promising technology for electrochemical energy storage. In this study, we present a high-performance alkaline zinc-iron flow battery in combination with a self-made, low-cost membrane with high mechanical stability and a 3D porous carbon felt electrode. The membrane could provide high hydroxyl ion conductivity while resisting zinc dendrites well owing to its high mechanical stability. The 3D porous carbon felt could serve as a guidance for the zinc stripping/plating, which can effectively suppress zinc dendrite/accumulation as well. Thus this battery demonstrates a coulombic efficiency of 99.5% and an energy efficiency of 82.8% at 160 mA cm?2, which is the highest value among recently reported flow battery systems. The battery can stably run for more than 500 cycles, showing very good stability. Most importantly, the practicability of this battery is confirmed by assembling a kilowatt cell stack with capital cost under $90/kWh.

13.
Nat Commun ; 9(1): 3731, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30213938

RESUMO

Alkaline zinc-based flow batteries are regarded to be among the best choices for electric energy storage. Nevertheless, application is challenged by the issue of zinc dendrite/accumulation. Here, we report a negatively charged nanoporous membrane for a dendrite-free alkaline zinc-based flow battery with long cycle life. Free of zinc dendrite/accumulation, stable performance is afforded for ∼240 cycles at current densities ranging from 80 to 160 mA cm-2 using the negatively charged nanoporous membrane. Furthermore, 8 h and 7 h plating/stripping processes at 40 mA cm-2 yield an average energy efficiency of 91.92% and an areal discharge capacity above 130 mAh cm-2. A peak power density of 1056 mW cm-2 is achieved at 1040 mA cm-2. This study may provide an effective way to address the issue of zinc dendrite/accumulation for zinc-based batteries and accelerate the advancement of these batteries.

14.
Chem Commun (Camb) ; 54(55): 7570-7588, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29876555

RESUMO

Flow batteries, aqueous flow batteries in particular, are the most promising candidates for stationary energy storage to realize the wide utilization of renewable energy sources. To meet the requirement of large-scale energy storage, there has been a growing interest in aqueous flow batteries, especially in novel redox couples and flow-type systems. However, the development of aqueous flow battery technologies is at an early stage and their performance can be further improved. As a key component of a flow battery, the membrane has a significant effect on battery performance. Currently, the membranes used in aqueous flow battery technologies are very limited. In this feature article, we first cover the application of porous membranes in vanadium flow battery technology, and then the membranes in most recently reported aqueous flow battery systems. Meanwhile, we hope that this feature article will inspire more efforts to design and prepare membranes with outstanding performance and stability, and then accelerate the development of flow batteries for large scale energy storage applications.

15.
Chem Soc Rev ; 46(8): 2199-2236, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28288217

RESUMO

Secondary batteries have received huge attention due to their attractive features in applications of large-scale energy storage and portable electronic devices, as well as electrical vehicles. In a secondary battery, a membrane plays the role of separating the anode and cathode to prevent the occurrence of a short circuit, while allowing the transport of charge carriers to achieve a complete circuit. The properties of a membrane will largely determine the performance of a battery. In this article, we review the research and development progress of porous membranes in secondary battery technologies, such as lithium-based batteries together with flow batteries. The preparation methods as well as the required properties of porous membranes in different secondary battery technologies will be elucidated thoroughly and deeply. Most importantly, this review will mainly focus on the optimization and modification of porous membranes in different secondary battery systems. And various modifications on commercial porous membranes along with novel membrane materials are widely discussed and summarized. This review will help to optimize the membrane material for different secondary batteries, and favor the understanding of the preparation-structure-performance relationship of porous membranes in different secondary batteries. Therefore, this review will provide an extensive, comprehensive and professional reference to design and construct high-performance porous membranes.

16.
Angew Chem Int Ed Engl ; 55(9): 3058-62, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26822866

RESUMO

Zeolites are crystalline microporous aluminosilicates with periodic arrangements of cages and well-defined channels, which make them very suitable for separating ions of different sizes, and thus also for use in battery applications. Herein, an ultra-thin ZSM-35 zeolite flake was introduced onto a poly(ether sulfone) based porous membrane. The pore size of the zeolite (ca. 0.5 nm) is intermediary between that of hydrated vanadium ions (>0.6 nm) and protons (<0.24 nm). The resultant membrane can thus be used to perfectly separate vanadium ions and protons, making this technology useful in vanadium flow batteries (VFB). A VFB with a zeolite-coated membrane exhibits a columbic efficiency of >99 % and an energy efficiency of >81 % at 200 mA cm(-2), which is by far the highest value ever reported. These convincing results indicate that zeolite-coated membranes are promising in battery applications.

17.
ACS Appl Mater Interfaces ; 7(34): 19446-54, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26284752

RESUMO

The stability of hydrocarbon ion exchange membranes is one of the critical issues for a flow battery. However, the degradation mechanism of ion exchange membranes has been rarely investigated especially for anion exchange membranes. Here, the degradation mechanism of polysulfone based anion exchange membranes, carrying pyridine ion exchange groups, under vanadium flow battery (VFB) medium was investigated in detail. We find that sp(2) hybrid orbital interactions between pyridinic-nitrogen in 4,4'-bipyridine and benzylic carbon disrupt the charge state balance of pristine chloromethylated polysulfone. This difference in electronegativity inversely induces an electrophilic carbon center in the benzene ring, which can be attacked by the lone pair electron on the vanadium(V) oxygen species, further leading to the degradation of polymer backbone, while leaving the 4,4'-bipyridine ion exchange groups stable. This work represents a step toward design and construction of alternative type of chemically stable hydrocarbon ion exchange membranes for VFB.

18.
Sci Rep ; 5: 8255, 2015 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-25653104

RESUMO

Separators with high reliability and security are in urgent demand for the advancement of high performance lithium ion batteries. Here, we present a new and practical porous membrane with three-dimension (3D) heat-resistant skeleton and high curvature pore structure as a promising separator candidate to facilitate advances in battery safety and performances beyond those obtained from the conventional separators. The unique material properties combining with the well-developed structural characteristics enable the 3D porous skeleton to own several favorable properties, including superior thermal stability, good wettability with liquid electrolyte, high ion conductivity and internal short-circuit protection function, etc. which give rise to acceptable battery performances. Considering the simply and cost-effective preparation process, the porous membrane is deemed to be an interesting direction for the future lithium ion battery separator.

19.
Phys Chem Chem Phys ; 16(37): 19841-7, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25135611

RESUMO

The degradation mechanism of hydrocarbon ion exchange membranes under vanadium flow battery (VFB) medium was investigated and clarified for the first time. This work will be highly beneficial for improving the chemical stability of hydrocarbon ion exchange membranes, which is one of the most challenging issues for VFB application.

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