Aluminum Collector Research Articles

Investigation of thermodynamics performance of solar dryer equipped with double pass flat, v-corrugated, and low-e coated collectors

In this study, a solar dryer incorporating a flat plate heat exchanger to recover heat from exhaust air was investigated to explore the usability of different types of collectors in the system. Their usability was further evaluated through economic and environmental analyses. Moreover, the thermodynamic performance of the solar dryers was evaluated under two weather conditions in Nepal. Apple drying experiments were conducted for 8 hours from 09:00 to 17:00 from February to April 2023 on solar dryers and with open sun drying (OSD) in Dhulikhel, Nepal. The results showed that the low emissivity (low-e) coated aluminum collector was more efficient in terms of collector efficiency and drying rate than collectors with flat or v-corrugated GI absorbers. The average collector efficiency and drying rate were found to be 89% and 107 g/(h×m2) using the low-e coated aluminum collectors, while the values were 50% and 84 g/(h×m2) for the GI sheet collector. The results indicated a slight improvement in the performance of v-corrugated collectors, with values of 53% and 89 g/(h×m2). The drying rate for OSD was found to be 78 g/(h×m2), which was lower than for the dryers with all collectors used in this study. In terms of economic analysis, the dryer equipped with the low-e coated collector was found to be superior, with a payback time of 1.61 years compared to the dryers with flat or v-corrugated GI collectors. Reducing the thermal losses due to radiation by using the low-e coated absorber was shown to be more important than increasing the absorber area using v-corrugated GI sheets.

A spray coated high performing metal-free onion-like carbon supercapacitor for sustainable energy storage

Supercapacitors will play a crucial role in the future energy landscape due to their high power density and extended cycle stability. However, energy density tends to be relatively low, partly because of conventional heavy current collectors, also posing sustainability issues. It is crucial to integrate lightweight, flexible current collectors and environmentally friendly active materials while maintaining the performance of the supercapacitor. Here we report on a metal-free supercapacitor using a carbon paper current collector and onion like carbon (OLC). The electrodes were fabricated through a scalable and flexible spray-coating process using onion-like carbon ink. Higher capacitances were observed for the paper-based electrode (24.1 F/g, 34.9 mF/cm2) compared to 22.5 F/g (31.5 mF/cm2) for aluminium collectors at scanrates of 2.5 mV/s over a voltage window of 2.5 V. At elevated scanrates of 100 mV/s–5 V/s, the actual operating window of a supercapacitor, the paper-based electrode offers a significantly enhanced performance. Stability tests demonstrated a capacitive retention of 98 % for both electrodes after 10,000 cycles. The utilization of onion-like carbon as the active material and a paper-based current collector enables the development of a fully carbon-based supercapacitor system, without compromising its electrochemical performance. This approach introduces a metal-free OLC supercapacitor and promotes environmental sustainability by reducing the dependence on conventional metal-based components and provides a more resource-efficient solution to address the energy storage needs.

Experimental Study of a Prototype Solar Water Heater Used in Sahelian Homes

Environmentally-friendly, low-cost energy supplies are the backbone of sustainable development. Development must not only meet current needs, but must also look to the future and consider environmental issues as a challenge. Solar power as an environmentally-friendly energy source is a promising way of reducing greenhouse gas emissions. One of the most important applications of solar energy is the production of hot water using solar water heaters. These solar water heaters, which can provide between 100 and 200 l/d of hot water over a temperature range of 40-70°C., are of the separate-element and integrated-storage types. In the Saharan environment, hot water requirements are concentrated in winter. It is therefore necessary to develop efficient systems adapted to this reality. It is then necessary to develop effective systems adapted to this reality. There is a need to propose a new design to boost the solar irradiation absorbed by the collector-storage while reducing nighttime thermal losses. For greater user-friendliness and with the aim of adapting them to the Saharan environment, it is also necessary to offer solar water heaters integrated into the building and operating mainly in the winter period. The present work represents an experimental study of a solar water heater with separate elements and a simple design, in a Burkinabe climate. This is a separate element solar water heater with a capacity of 200 liters with an aluminum collector as absorber designed at the Research Institute of Applied Sciences and Technologies (IRSAT). The water in the tank forms a loop with the sensor. In the tank, donut a copper coil of a length equal to 15m with a diameter of 16mm. They use the principle of thermosyphon (cold water pressure) to circulate and store heat and are simpler and less expensive, but can only be installed in sunny countries and have limited efficiency. During the measurement period from 11:25 a.m. to 4:05 p.m., the maximum temperature of the hot water was around 57°C at 11:45 a.m., and that of the cold water was around 27°C at 12:15 p.m.. The experimental results showed acceptable thermal performance despite the simplicity of the sensor. Finally, an improvement can easily be made whether by perfecting the thermal insulation or using selective collection surfaces.

Design and performance evaluation of Front glass-covered photovoltaics-thermal hybrid system for enhanced electrical output and hot water production

Proof of concept is established for the thermal management of PV modules for the simultaneous benefit of electrical and thermal efficiency. It was achieved by designing the controlled open-loop water-based hybrid PV-T system and demonstrated for thermal management of 150W photovoltaic panel at natural solar conditions. In this integrated front glass-covered PV-T hybrid (IFG-PV-T) system, the PV panel is clipped between the front glass and rear aluminium collector without causing any permanent changes in the existing panel. The flow of water from the source tank is controlled by automated solenoid valve assembly coupled with thermocouples. The solenoid operational temperature is fixed at 40°C to controlled the PV surface temperature at an optimum range to mitigate the adverse effect on voltage and current output. The water layer thickness in the front glass box is optimized to filter the maximum infrared radiations and the collector's toughened glass feature allows the maximum light transmittance with super safety. The performance of the IFG-PV-T system has been evaluated in terms of variation in open circuit voltage, short circuit current, maximum power output, electric and thermal efficiency under the natural solar insolation for a week. Experimental investigations revealed that the open-circuit voltage is increased by ∼16.1 % with IFG-PV-T as compared to conventional PV panel. The increment can be attributed to the synergy of the front glass collector and solenoid valve operation at 40oC that regulates PV surface temperature and boost the current output. These factors have ameliorated the electrical efficiency of IFG-PV-T compared to conventional PV panel. The average thermal efficiency was 39.4 ​% wherein the IFG-PV-T system provides ∼100 ​L of hot water (38–41 ​°C) per day. The present controlled loop operation system and collector configuration have proven their significance for electrical power increment and concomitantly able to deliver moderate hot water which can be useful for any household or commercial application.

Development of electroforming technology for flexible metal substrates for high-efficiency double-sided electronic devices

In this study, we investigate a novel material that surpasses conventional concepts used for substrate materials in flexible electronic devices. Unlike traditional materials, this novel material can replace polymers with a metallic substance. This substance is capable of supporting electronic devices on both sides. Our development focuses on a metallic substrate material based on Fe-Ni. This material allows for the implementation of secondary batteries on its extremely flat opposite side through the electroforming method. The Fe (Iron)-Ni (Nickel) material produced by electroforming shows superior characteristics in terms of coefficient of thermal expansion (CTE) and mechanical properties. This superiority is due to its finer grain size, compared to Fe-Ni produced by the rolling process. Furthermore, when we use the Fe-Ni material to manufacture secondary batteries, it demonstrates equivalent or superior battery characteristics compared to the conventional aluminum (Al) collector material. During thermal shock tests, the Fe-Ni material also shows superior adhesion compared to the traditional Al collector. This advantage is attributed to Fe-Ni's low CTE. Our approach enables the implementation of secondary batteries for power generation on one side and the manufacture of electronic components for power consumption on the other. This creates a new concept for flexible substrate materials.

Morphological, Mechanical and Thermal Characteristics of PLA /<i>Cocos nucifera</i> L Husk and PLA/<i>Zea mays</i> Chaff Lignin Fibre Mats Composites

Polylactide (PLA) is a biodegradable polymer with low elongation which limits its use in some applications. The incorporation of biowaste particles has been employed to improve its properties. This work thus examines the impact of lignin particles reinforced on electrospun PLA fibre mats. Acid hydrolysis (1M of HCl at 60 and 100 oC for 2 and 4 h was used to extract lignin from Cocos nucifera L (CNHL) and Zea Mays Chaff (CCL). Lignin particles were added to molten PLA, stirred, and electrospun at 26 kV, using a static aluminum collector plate placed at 121mm from the spinneret tip. Morphological examination reveals that fibre diameter of neat PLA (9.7 µm) increased from 107 – 285 % with the additions of reinforcements. Maximum tensile strength of 1.03 MPa is recorded for PLA/CNHL 60oC /2 h. This composite maintains the highest elongation of 0.069 % compared to neat PLA (0.046 %). X-Ray diffractometer (XRD) result informs that the crystallinity of neat PLA (67.6 %) improves by 3%, with the use of CNHL 60 oC/ 2 h. Thermo gravimetric analysis (TGA) result shows that both fibre composites possess better thermal stability (380 oC) compared to reinforcing PLA fibre (319 oC).

Towards Efficient Polymeric Binders for Transition Metal Oxides-based Li-ion Battery Cathodes.

Transition metal oxide cathodes (TMOCs) such as LiNi0.8Mn0.1Co0.1O2 and LiMn1.5Ni0.5O4 have been widely employed in Li-ion batteries (LIBs) owing to superior operating voltages, high reversible capacities and relatively low cost. Nevertheless, despite significant advancements in practical application, TMOC-based LIBs face great challenges such as transition metal dissolution and volume expansion during cycling, which jeopardizes the future advance of high-voltage TMOCs. As a critical component of cathode, polymeric binder acts as a crucial part in maintaining the mechanical and ion/electron conductive integrity between active particles, carbon additives, and the aluminum collector, hence minimizing cathode pulverization during battery cycling. Moreover, Polymeric binder with specialized functions is thought to offer a new solution to enhancing the electrochemical stability of the TMOCs. Therefore, this review aims at providing a comprehensive summary of the ideal requirements, design strategies and recent progress of polymeric binders for TMOCs. Future design perspectives and promising research technologies for advanced binders for high-voltage TMOCs are introduced.

Tailoring the passivation layer on lithium metal anode and aluminum collector by regulating the solvation structure to enhance the long-term cycling of lithium metal batteries

Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) is widely employed in lithium metal batteries (LMB) owing to its capacity for efficiently mitigating the growth of lithium dendrites and enhancing the interface stability of lithium metal anodes. Unfortunately, LiTFSI frequently causes severe aluminum (Al) corrosion and leads to LMB failure. To address this issue, we conducted solvation structure design in the electrolyte using co-solvents such as 1,2-diethoxyethane, fluoroethylene carbonate and adiponitrile. Both experimental and computational evidences demonstrate that the co-solvents can regulate the solvation structure of electrolyte and promote the formation of more anion-rich internal solvation shells, ultimately enhancing the interfacial stability of Li anode and Al collector. When paired with high-loading LiFePO4 cathode, the full cell exhibits a long-term lifespan (1000 cycles) and outstanding capacity retention (86.4 %). Even the full cell with stringent conditions of NMC811 (∼4.0 mAh cm−2), 50 μm thin Li (N/P = 2.5) and the optimized electrolyte still enables to output over 110 cycles and 80.0 % capacity retention. This work provides an efficacious and innovative strategy to stabilize Li metal anode and Al current collector through solvation structure regulation.

Recovering the Cathode Material Adhered to the Collector and Separator of Spent Lithium-Ion Batteries for Recycling Purposes

Depleted Li-ion batteries (LIBs) must be recycled for environmental and sustainability reasons. Most recycling processes are dedicated to the recovery of Li, Co, Mn, and Ni present in the cathode material of LIBs. However, separating the cathode material strongly adhered to the aluminum collector and those mechanically trapped into the polymeric separator is still challenging. Processes to separate the cathode material by dissolving its aluminum collector in NaOH solution and to extract part of this material encrusted in the separator by ultrasonic cavitation and mechanical friction are presented in tests with NMC batteries on a laboratory scale. Tests of LIB discharges were also carried out in different MnO4 solution concentrations, and the related electrochemical reactions were discussed.

TOPLAYICI PLAKA MALZEME VE KALINLIĞININ ELEKTROSPUN ELYAF İNCELİĞİ ÜZERİNDEKİ ETKİSİNİN TEORİK BİR ANALİZ İLE İNCELENMESİ

The aim of this study is to examine the morphological properties of fibers produced by using metal plates of different thickness and materials as collectors in electrospinning. For this, circular shaped aluminum and copper plates of 1 mm, 5 mm, 10 mm thickness were used. The results show that much finer fibers were obtained when copper collectors are used compared to aluminum collectors. When the effect of collector thickness is analyzed, it was observed that fiber fineness increased as the collector thickness increased. In addition, it was observed that collection area of fibers on collector is much larger when aluminum collector and thinner collector is used showing that collector material and collector thickness affect fiber arrangement and interfiber spacing in electrospinning. A theoretical approach is also included in this work regarding effect of collector thickness and collector material type together with its verification in the light of experimental results.

Investigation of the corrosion behavior influence of carbon interlayer on aluminum collector in lithium-sulfur battery system

Due to the shuttle effect brought by polysulfides, the commercialization of lithium-sulfur batteries still faces significant difficulties. Carbon interlayer is introduced to enhance the electrochemical performance of lithium-sulfur batteries, while the drawback that the interlayer will reversely affect the performance of the current collector was ignored. The current collector has a significant influence and contribution to the cycle stability of lithium-sulfur batteries. In this study, we looked into the electrochemical stability and corrosion situation of standard aluminum foil collectors in lithium-sulfur batteries with carbon interlayer. The results show that the introduction of carbon interlayer into the lithium-sulfur batteries will make aluminum foil and carbon paper form an electronic conduction path and galvanic corrosion occurs, accelerating the corrosion of aluminum foil. Therefore, we propose a new corrosion model. During the cycle, the surface of the aluminum collector becomes a non-dense passivation film and lithium polysulfide terminal (ST−1). Then, under the action of the carbon interlayer, the passivation film peels off and the oxide film is attacked by the electrolyte, thiosulfate and polythionate, resulting in pitting holes and ultimately accelerating the corrosion of the aluminum foil collector. This research has some guiding significance for the commercial application of lithium-sulfur batteries.

Room temperature efficient regeneration of spent LiFePO4 by direct chemical lithiation

Herein, we report a direct recycling process of the spent LiFePO4 by direct room temperature chemical lithiation. A fine characterization of a recovered LFP cathode from a spent commercial battery demonstrates that the end of life of the battery is mainly due to the lithium loss, while the structure of the LFP cathode material is globally preserved. It is shown here that such a cathode can be efficiently recovered by direct lithiation in solution using LiI in different solvents (acetonitrile, ethanol, cyclohexane, methanol, DMSO and propan-1,2-ol) with optimized experimental parameters. The best electrochemical performance is obtained with ethanol, one of the greenest and cheapest solvents, without any additional heat treatment. More interestingly, the regeneration of LFP can be achieved directly with the material cast onto its aluminum collector, which paves the way to more efficient recycling preserving the whole electrode formulation and avoiding a new electrode casting. The chemically lithiated LFP cathode in ethanol exhibits a full reversible capacity of ∼168 mAh/g vs. Li metal with a stable coulombic efficiency exceeding 98% for 25 cycles. In addition, this recovery process produces regenerated electrodes showing good electrochemical performance also at high current density.

Improving performances of cathode-electrolyte interphase via the potentiostatic reduction of lithium bis(fluorosulfonyl)imide additive

The low concentration electrolyte shows the advantages of low viscosity and low cost, but the formation of porous and soluble organic cathode-electrolyte interphase (CEI) limits its performance. Herein, the electrochemical performance of the low concentration electrolyte of 0.45 M LiPF6‑diethyl carbonate (DEC)/ ethylene carbonate (EC) (1:1, in volume ratio) is improved by 0.05 M bis(fluorosulfonyl)imide (LiFSI) additive, aided by the antecedent process of potentiostatic reduction at a low potential of 1.5 V. Results show that LiFSI is preferentially reduced via breaking the structure of FSI− anion to form a robust LiF-rich CEI on the surface of LiFePO4 (LFP) cathode, solving the problem that it is difficult to form inorganic LiF on the cathode surface. In the subsequent cycling of LFP/Li half-battery, the as-formed CEI inhibits the corrosion of aluminum collector, suppresses the excessive decomposition of the electrolyte and improves the diffusion of Li+, resulting in a much-enhanced cycle stability of the cathode. Therefore, the cyclic performance of the LFP/Li half-battery using the modified low concentration electrolyte with the antecedent process of potentiostatic reduction is on a par with that using the standard electrolyte (1.0 M LiPF6-DEC/EC). Compared with the traditional electrolyte engineering of constructing a LiF-rich CEI by the direct oxidation defluorination of fluorinated anions, this strategy needs a lower reaction energy and can play a positive role at a lower reaction potential. This work provides an effective way to construct LiF-rich CEI which helps to improve the performance of low concentration electrolytes.

A comparative study of high density Vertically Aligned Carbon Nanotubes grown onto different grades of aluminum – Application to supercapacitors

Vertically aligned carbon nanotubes (VACNT) have received extensive attention as electrode materials for supercapacitors owing to their superior features: no formatting or binder needed, anisotropy. They can be obtained by aerosol-assisted Catalytic Chemical Vapor Deposition (CCVD), a cost-effective and roll-to-roll compatible process, directly onto aluminum current collectors by lowering their growth temperature. In this paper, a comparative study of high density VACNT grown onto different grades of aluminum collectors is performed. Influence on electrochemical performances of carpet thickness up to 170 μm and VACNT volumetric density ranging from 70 to 350 mg/cm3 is evaluated. VACNT electrodes exhibit high areal capacitance up to 360 mF/cm2 and 25 F/cm3 and average gravimetric capacitance is 45 F/g. At high scan rate volumetric density has low impact while increasing height of VACNT limit performances. Symmetrical supercapacitor based on VACNT/Al electrodes assembled in coin-cell exhibits high energy and power density with high potential difference of 2.7 V and great energy retention capacity (90% at 13 A/g). Such results outline the benefits of the VACNT growth process directly applicable to aluminum current collector meeting industrial requirements (high purity and thin thickness) and exhibit the huge potentialities of such electrode to realize in supercapacitor applications.

Hybridization of Mesoporous Carbon and Iron Oxide for Better Mitigation of Polysulfide Shuttling in Li-S Batteries

With a higher theoretical capacity, lithium-sulfur (Li-S) batteries have been considered as promising candidates for next-generation batteries. Due to the non-conducting nature of sulfur, however, lithium-sulfur batteries tend to exhibit poor performance at a high current rate (C-rate).Here we demonstrate that Fe3O4, synthesized from precursor iron (III) acetylacetonate (AAI), and mesoporous carbon material, Ketjen Black (KB), can be synergistically combined to enhance the electrochemical performance of lithium-sulfur batteries substantially. Instead of adding commercial magnetite particles into Li-S cathodes, iron oxides are synthesized and imbedded into KB from a precursor, AAI, through thermal treatments in air and Ar. The sulfur, then, is incorporated into iron oxides/KB hybrids by melting at an elevated temperature. With air-controlled electrospray as the processing method, sulfur embedded iron oxides/KB, poly(acrylic acid), and rGO sheets are mixed and directly deposited onto the carbon-coated aluminum collector, to employ as the Li-S battery cathode. X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS) studies confirm that Fe3O4 and iron carbide (Fe3C) are synthesized from the precursor, AAI, embedded in mesoporous carbon materials, and reducing the charge transfer resistance of batteries. The rate-capability tests show that systems with KB/Fe3O4 can achieve enhanced performance compared to batteries without iron oxides, especially at high C-rates. With 14 wt % of solid materials as iron oxides and iron carbide, batteries exhibit 750 mAh/g at 2C discharge/charge rates, which is 83% higher compared to systems without iron oxides. However, incorporated via 250 °C for 0.5 hr in air and 850 °C for 2 hr in Ar, the composite of KB/Fe3O4/Fe3C induces irreversible side reactions during the initial charging process, which causes a huge difference in capacity between the first and the second cycle. To achieve an optimal status with improved rate capability and acceptable initial charging time, we modify the thermal treatments and thus increase the proportion of Fe3O4 in the mixture. According to the postmortem analysis, cathodes with iron oxides can interact with soluble polysulfides strongly and alleviate the polysulfide shuttle effect significantly, compared with those without Fe3O4. Such enhanced rate capability by KB/Fe3O4 (synthesized) over KB only or KB/Fe3O4 (commercial) systems suggests that the incorporation of iron oxides can play an important role in improving the electrical conductivity of cathode and mitigating polysulfide shuttle effect. Figure 1

Atomisation of nanometre-scaled jasmine flower extracts using electrospray method

The present work demonstrated the application of a non-thermal technique to solidify nanometre-scaled atomised droplet using electrostatic atomiser or electrospray. The droplets were prepared in an aqueous solution, and consisted of bioactive compounds extracted from jasmine flower. The jasmine flower extracts were electrosprayed at various concentrations of 5, 15, and 25 wt%, with the working distances between the needle’s tip to an aluminium collector being 10, 20, and 30 cm. During the process, the water evaporation rate decreased from 2.02 to 1.02 nm3/s when the distance was increased from 10 to 30 cm at 5 wt% concentration. The same decreasing evaporation rate pattern was also observed when the concentration was increased from 5 to 25 wt%. On the contrary, increasing droplet fission numbers were observed as the distance was increased from 10 to 30 cm (i.e., from 7 to 406 at 25 wt% concentration) due to the electrostatic charge increment per unit area as the water left the droplet surface. Therefore, water evaporation and droplet fission number are important for solidifying the compounds when the droplets have exceeded their Rayleigh limit.

Electrospun nanofibrous yarn based piezoresistive flexible strain sensor for human motion detection and speech recognition

This work reports the development of highly sensitive Piezoresistive flexible strain sensor for human motion detection and speech recognition. Initially, a conductive polymer composite (CPC) solution comprising of thermoplastic polyurethane and Carbon Nanoparticles was prepared using Dimethylformamide as solvent and Chloroform as dispersant with the composition of 50% v/v. The solution was heated to a temperature of 60°C for evaporation of the solvent until it contained 13.5% w/v solvent for steady electrospinning. In this way, the CPC solution was used to develop Electrospun Nanofibrous Yarns (ENFYs) by applying a potential difference of 40 KV between the electrospinning needle and Aluminum collector. A cotton fabric was wrapped on the Aluminum collector to allow twisting of the deposited electrospun nanofibers. This novel collector configuration resulted in the formation of nanofibrous yarns due to the whirling action of the advancing jet of CPC solution. The cotton fabric on the collector facilitated twisting of fibers by allowing them to roll over the fabric. The fabricated ENFY sensors showed remarkable stretchability up to 102% strain while achieving a gauge factor of 70 at 100% strain. Long-term usage necessitates repeatability, which was demonstrated by cyclic loading at a crosshead speed of 40 mm/min for up to 1000 cycles using a custom-developed linear actuator, with no signs of fracture. ENFY strain sensor was attached to different parts of human body such as finger, fist, elbow, knee and ankle and was found capable of measuring and observing angle, position and frequency of motion. Owing to its ultrasensitive behavior, the developed sensor was able to measure heart rate as well. When the developed sensor was attached to Adam’s apple for speech recognition it showed remarkable response towards different utterances and breathing and gulping actions with clearly distinguishable signals. These results demonstrate that the developed novel ENFY flexible strain sensor can be employed for proprioceptive sensing and speech recognition for human-machine interaction, soft robotics and wearable devices etc.

Revisiting the corrosion mechanism of LiFSI based electrolytes in lithium metal batteries

Lithium bis(fluorosulfonyl)imide (LiFSI), regarded as one of the most promising alternative of lithium hexafluorophosphate (LiPF6), seriously weakens the electrochemical performance of lithium metal batteries at high voltages, due to its extreme corrosion in nonaqueous electrolyte towards some components of the batteries. Though studies have shown that the aluminum (Al) collector will be corroded in LiFSI electrolytes, few attentions have been paid to the corrosion of steel components of lithium metal batteries, the corrosion intensity of which is much more severe than that of Al. Herein, by comparing the electrochemical corrosion behaviors of Al foil and stainless steel (SS) in LiFSI electrolytes, the corrosion products were characterized and analyzed, and the corrosion mechanism of SS was further proposed. Based on the corrosion mechanism, a strategy to inhibit the corrosion by using high concentration electrolyte (HCE) was also proposed. Moreover, introduction of 1,1,2,2-tetrafluoroethyl 2,2,2-trifluoroethyl ether into HCE, forming a localized high concentration electrolyte (LHCE), which not only addresses the viscosity and wettability issues of HCE but also inhibits the corrosion in conventional concentration electrolyte. As a result, Li||LiCoO2 coin cells using HCE and LHCE show excellent cycling stability with capacity fading rates of 0.53% and 0.26% per cycle, respectively, at 1 C (1 C = 180 mAh g − 1) between 3 – 4.45 V. The same corrosion inhibition regular also has been proved in pouch cells.

Synergistic effect of ultrasonication and sulfate radical on recovering cobalt and lithium from the spent lithium-ion battery

Ultrasonication has been mechanically applied widely in the recycling of spent lithium-ion (SLI) batteries while its influence on chemical pathways has barely been reported. In this study, ultrasonication and sulfate radicals were used in a coupling system to obtain efficient recoveries of Co and Li from SLI batteries. The synergistic effect of ultrasonication and sulfate radicals on recycling was quantitatively analysed by significance analysis and surface responses in a central composite design. The employment of persulfate significantly affected the whole recycling process during the sonication. Factors including acoustic time, operating powers, and temperature all had a significant effect on the recoveries of Co and Li. The maximum recovery efficiencies of Co and Li of 97.33% and 99.25%, respectively, and the minimum loss rate of Al of 4.13% were simultaneously obtained by the fitting predictor. The optimal combination of factors for the sonication system included an acoustic time (min) of 5.5, an operating power (W) of 168, a temperature (°C) of 86, and a ratio of cathode foil to S-solution (mg/mL) of 1:60. A moiety of cathode active material was directly separated from the aluminium collector by sulfate radical-related reactions. Co and Li cations dissolved from LiCoO2 by carbon dioxide radicals were reprecipitated by excess oxalate. The research demonstrated the positively synergistic influence caused by ultrasonication and sulfate radicals on achieving efficient recoveries of Co and Li from SLI batteries, explicitly expanding the technical choices for the recycling procedure.

The effect of collector parameters on nanofiber yarns produced by electro yarn spinning machine with conical collector

In this work, electrospun yarns were produced by a nanofiber yarn spinning machine with a conical collector. In the first part, two different polymers (PAN and PVDF-HFP) were used in nanofiber yarn spinning with two different types of conical collector which are made of stainless steel and aluminium. In the second part, four different types of aluminium collector having different wall thickness and surface properties were used. For all yarns produced, the effect of different parameters has been analyzed in terms of fibre fineness distribution, yarn fineness and yarn linear density, yarn strength and breaking elongation. The results show that yarns produced by using aluminium collector are finer and have higher strength compare to the ones produced by stainless steel collector while PVDF-HFP nanofiber yarns are finer and have higher tensile strength compare to PAN. The results also show that yarns get coarser while fibres get finer as the collector wall thickness is increased in general.