bluuebunny/crossref_metadata_2025_split huggingface dataset:
Technical and Economic Analysis of Pemfcs and DMFCs for Material Handling Applications
Authors: Metzger Nathaniel , Li Xianglin 
Published: December 2020

There has been tremendous growth in the material handling industry partially driven by the fast-growing logistics industry. As the major transport equipment, forklift trucks powered by internal combustion engine and petroleum-driven fuels such as gasoline, diesel, or liquefied petroleum gas (propane) historically dominate the forklift industry. Within the 850,000 total forklifts in use across the United States, there are only more than 20,000 forklifts driven by fuel cells. Based on available forklift deployment data between 2004 and 2014, it is estimated that only about 6% of fuel-cell forklifts are driven by DMFC. DMFC-driven forklifts have huge growth potentials due to its low infrastructure cost, low fuel cost, and easy handling of liquid methanol. As a result, the research team will analyze the technical and economic feasibility of DMFCs as the next generation power source for the material handling industry.
Preliminary analyses have compared the life cycle cost (LCC) of PEMFC forklifts and DMFC forklifts. The analyses include the cost of fuel cell components, balance of plant (BOP), system assembly, fuel cost, performance of the fuel cell, as well as the average operating conditions of Class I, II, and III forklifts. If the hydrogen price is assumed to be $8/kg, the min LCC ($36,682) of the PEM fuel cell is reached at a moderate current density (533 mA/cm2). Due to the high price of hydrogen, the fuel cost over the lifetime ($26,415 or 72%) is counted for the majority of LCC while the cost of infrastructure and fuel cell installation ($10,267 or 28%) makes up the rest of LCC. The LCC of PEM fuel cell is very sensitive to the hydrogen price. When the hydrogen price varies between $4/kg and $12/kg, the LCC changes between $23,079 and $49,691.
The min LCC ($43,308) of the DMFC is reached at a similar current density (591 mA/cm2). Even though DMFC has much lower efficiency (27%) at the min LCC than PEM fuel cell (60%), the fuel cost of DMFC over lifetime ($17,273) is lower than that of the PEM fuel cell because hydrogen price is at least an order of magnitude higher than methanol price per heating value. Since DMFC uses much more PGM catalyst than PEM fuel cell to generate the same amount of power, DMFC’s installation cost accounts for the majority (60%) of DMFC’s LCC. Comparisons between the LCCs of DMFC and PEMFC indicate that DMFC could be a more economic feasible technology than PEMFC for Class I and II forklifts in relatively small warehouses with less than a dozen forklifts and/or if the hydrogen price is high (>$10/kg).
Effect of Pt Solution Concentration during Direct Preparation of Core–Shell Pt Cathode in MEA Catalyst Layer for PEFC
Authors: Fukunaga Hiroshi , Tsuji Masayasu , Ito Yu , Takimoto Daisuke , Sugimoto Wataru 
Published: December 2020

Core-shell catalyst, which consists of thin Pt shell on non-Pt metal core, has been attracting attention as a low-Pt catalyst for polymer electrolyte fuel cell (PEFC). Typically, it is synthesized by using Cu-underpotential deposition (Cu-UPD) followed by surface limited redox replacement (SLRR). However, since this method is normally performed on a rotating disk electrode, it can only be prepared on a microgram scale. We have been developing a novel method to overcome this problem by directly performing Cu-UPD and SLRR to the catalyst layer made from the core material. Using this method, the reaction area is increased since the reaction occurs on particles in the three-dimensional network. In our previous study, we have reported that a Pd@Pt/C catalyst layer prepared by this method shows higher mass activity than conventional Pt/C. However, deposition at the surface of the catalyst layer appeared to be larger than in the interior of the layer. In this study, the effect of Pt ion solution concentration on the Pt deposition behavior was studied to develop highly active low-Pt catalyst layer by this novel method.
Pd/C was used to fabricate a catalyst layer made of core material. Cu-UPD and SLRR was performed twice on this catalyst layer. In the SLRR process, Pt ion solution with various concentration was used. When a high concentration solution was used, large deposition at the surface was apparent. On the other hand, when a low concentration solution was used, the deposition at the surface was suppressed but the amount of Pt deposition was insufficient. By using both the low and high concentration solution, metallic luster caused by the large depositon of Pt was not observed, and a sufficient amount of Pt was deposited. The performance of a MEA prepared by this catalyst layer showed higher performance than that prepared by the previously reported method.
Characterization of Sulfonylated Poly(styrene) Based Proton Exchange Membranes for Fuel Cells
Authors: Dueerkop Dennis , Zalewski Laura , Schmiemann Achim 
Published: December 2020

The change from an energy industry based on fossil fuels to an energy industry based on renewable energy sources is a global challenge. For this reason, dynamic storage systems are needed to be developed for fluctuating wind and solar energy. Water electrolysis and fuel cells are important energy converters that offer the possibility of using hydrogen as an energy carrier. Generally, good thermal-oxidative stability and high proton conductivity are expected for membranes in fuel cells [1].
As an alternative to perfluorosulfonic acid based membranes, hydro-carbon based proton exchange membranes may reduce stack costs. This assumption motivates us to synthesize and investigate polymer membranes whose proton conductor is cross-linked sulfonated sulfonylated poly(styrene) (ssPS). The advantage of ssPS in contrast to sulfonated polystyrene is the stability of the sulfonic acid group at temperatures around 100°C [2]. Disadvantages of ssPS are the water solubility at high degrees of sulfonation (ion exchange capacity of about 3,5 mmol/g) and poor film formation properties.
According to this, the proton conductor must be cross-linked during synthesis and embedded in a nonpolar polymer matrix during the membrane production.
Our investigations show that ssPS (non-cross-linked) has a similar thermal-oxidative stability as Nafion® (examined by thermal analysis/oxidative induced temperature (OIT)) [3]. The cross-linking of ssPS with divinylbenzene mixtures leads to a less good thermal-oxidative stability. Furthermore, our results show that the water uptake can be adjusted by varying the amount of cross-linker. In addition, the proton exchange membranes show conductivities in the range of Nafion® 117 at room temperature.
The presentation will show the development of a new proton exchange membrane and its characterization. To discuss the membranes quality, the focus is on ion exchange capacity (stability at 90°C), thermal-oxidative stability (differential scanning calorimetry), water uptake and electrical resistance as a function of temperature up to 90°C.
This work is supported by the Federal Ministry of Education and Research (BMBF).
[1] J.A.Kerres, A.Katzfuß, A.Chromik, V.Atanasov, J. Appl. Polym. Sci. 2014 , 131 , 39889.
[2] H.Widdecke, M.Dettmer, W.Reith, Patent DE4425216C2, 2003.
[3] G.W.Ehrenstein, G.Riedel, P.Trawiel, Thermal analysis of plastics, Hanser Verlag, 2004.
Influence of Oxygen Vacancy on Pseudocapacitance of La0.8Sr0.2CoO3-δ
Authors: Lannelongue Pierre , Abdollahifar Mozaffar , Wu Nae-Lih (Nick) 
Published: December 2020

Since the discovery of the charge storage mechanism involving a charge compensation by anion that can happen for some pseudocapacitive materials, oxides from the perovskite family have been intensively studied during the past five years, such as LaMO3-δ (M = Mn, Fe, Co, Ni). The oxygen vacancy present in some perovskites naturally becomes the center of this new mechanism. Indeed, the vacancies are suggested to host oxygen/hydroxyl ions to compensate the oxidation of the transition metal, and to release these ions during the reduction. Interestingly, there has not been any report dedicated to reveal the correlation between the oxygen vacancy with the pseudocapacitance of these materials.
We propose here the study of the influence of the oxygen stoichiometry of the perovskite La0.8Sr0.2CoO3-δ, written as LSC82, used as pseudocapacitive electrode material. LSC82 has been prepared by a urea-nitrate combustion method, and then calcined at 850°C. Materials having different oxygen stoichiometries were obtained by different cooling rates. Electrochemical tests were performed on LSC82 based electrodes in 5M LiNO3 electrolyte to reveal the correlation between the oxygen stoichiometry and pseudocapacitve performance. The oxidation states of Co and the oxygen vacancies content in the various prepared LSC82 have been determined by various technics such iodometric titration, X-ray Absorption Spectroscopy and X-ray Photoelectron Spectroscopy. By associating electrochemical tests with spectroscopic technics, it is possible to connect oxygen vacancies content with electrochemical performances.
Understanding the role of oxygen vacancies could give new lead to improving the performances of such materials.
All-Solid-State Al – Graphene Hybrid Supercapacitor
Authors: Tak Yongsug , Seon Eunbin , Kim Isak 
Published: December 2020

With the recent growth of interest in wearable electronics, gel electrolytes or solid electrolytes of energy conversion devices such as batteries and capacitors have been actively studied. All-solid-state supercapacitor has advantages such as high power density, outstanding mechanical stability, and long cycle life. However, the low energy density of supercapacitor makes it difficult to replace the battery. Therefore, a hybrid supercapacitor combining a battery and a supercapacitor has been significantly attracted.
In this study, aluminum as a battery electrode and graphene as a capacitor electrode were hybridized in a cell and ethyl acrylate and ionic liquid were used to make a polymer gel electrolyte. Aluminum has high energy density due to three-electron reaction and can be considered as a promising battery type electrode of a hybrid supercapacitor. Conversely, graphene is appropriate for capacitor type electrodes owing to its large specific surface area (~2675 m2 g-1) and high theoretical capacity (550 F g-1 ). With the increase of charge/discharge cycling, the dissolution and deposition reactions of aluminum were repeated and the contact of the aluminum anode and gel electrolyte decreases, which can result in a decrease in capacitance and cycle stability. Two strategic approaches were applied to improve the cell performance and charging-discharging behaviors were investigated with the variations of aluminum surface morphology. Firstly, aluminum metal was electropolished to remove the surface oxide film and applied as an anode. Secondly, thin aluminum metal film was prepared with electroplating and tested as an anode. Electrochemical Impedance Spectroscopy (EIS) was used to characterize the gel electrolyte and to measure the contact resistance between electrolyte and the surface-treated aluminum. SEM and XRD were used to analyze the aluminum surface structure.
(Battery Division Postdoctoral Associate Research Award Address Sponsored by MTI Corporation and the Jiang Family Foundation) Li Plating During Fast Charge: Detection and Prevention
Authors: Rodrigues Marco-Tulio , Abraham Daniel P. 
Published: December 2020

Enabling fast charge of lithium-ion batteries is an essential step towards the wider adoption of electric vehicles. A key challenge is that high charging currents can promote several aging mechanisms, including lithium plating on the graphite anode. There is research suggesting that the deposition of metallic lithium favors further Li plating in a self-reinforcing loop, which can eventually lead to sudden cell failure.[1] Hence, detecting Li deposition during the early stages and developing electrochemical cycling protocols that avoid plating conditions are crucial to enabling fast-charge.
In this talk we will discuss two approaches to investigate Li deposition. The first one is through detection. Our group has demonstrated that plated Li can intensify the Raman signal of its surrounding SEI, which then serves as an indirect marker for the presence of Li nuclei.[2] The sensitivity of this technique enables the study of where Li will tend to plate, and how this deposition evolves spatially over the course of many cycles. The second approach is through the use of a reference electrode, which can be used to estimate electrode potentials during fast charging.[3] This capability supports the development of fast-charging protocols that optimize time utilization while steering the cells away from Li plating conditions. Examples of such cycling protocols will be discussed during the presentation.

References

[1] X.-G. Yang, Y. Leng, G. Zhang, S. Ge, C.-Y. Wang, Journal of Power Sources, 360, 28-40 (2017)
[2] M.-T. F. Rodrigues, V. A. Maroni, D. J. Gosztola, K. P. C. Yao, K. Kalaga, I. A. Shkrob, and D. P. Abraham, ACS Applied Energy Materials, 2 (1), 873-881 (2019)
[3] M.-T. F. Rodrigues, K. Kalaga, S. E. Trask, D. W. Dees, I. A. Shkrob, and D. P. Abraham, Journal of The Electrochemical Society, 166 (6), A996-A1003 (2019)

Acknowledgements:
We are grateful to the U.S. DOE Office of Vehicle Technology Extreme Fast Charge Cell Evaluation of Lithium-Ion Batteries (XCEL) Program managed by Samuel Gillard. This document has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357.
Analysis of the Impact of Fast Charging on Aging for Smartphone Cells: A Case Study Using Synchrotron Based Techniques
Authors: Besli Muenir Mustafa , Subbaraman Anantharaman , Ramezan Pour Safaei Farshad , Metzger Michael , Ravi Nikhil , Johnston Christina , Christensen Jake , Kuppan Saravanan 
Published: December 2020

With the rapid market increase of consumer electronic devices such as smartphones and tablets, the performance of lithium-ion batteries (LIBs) in such devices becomes an important factor. In particular, fast charging, longer lasting batteries and safety are primary concerns for consumers. Lithium cobalt oxide (LCO) is a common cathode material for these applications, and in smartphone applications with 1-2 cycles a day, LCO has been proven to be a good cathode with its high cycle life.1,2 However, besides offering high cycling stability and power density for mobile consumer applications, another requirement for LIBs utilized in smartphones and other portable electronic devices is the capability of fast charging, without a detrimental impact on the cycling stability. Different fast charging profiles can lead to various extents of degradation within the full cell. Consequently, strategies are needed to avoid or mitigate any negative impact of fast charging on battery capacity, power degradation and cycle life.
In this work, we employed extensive synchrotron-based characterization methods on smartphone batteries (LCO/graphite), offering new insight into the various degradation mechanisms during fast charging. Specifically we focus on an in-house developed fast-charging profile based on a physics-based battery model and compare it with the fast charging profile provided by the OEM. We reveal how lithium plating occurring on the anode side during fast charging is ‘mirrored’ on the cathode side leading to inactive cathode areas that only participate partly in lithium intercalation. While no morphological changes were observed in the cathode opposing the plating sides on the anode, in-situ hard XAS spectroscopy shows that deactivated spots on the cathode are not as redox active anymore, and synchrotron micro XRD shows significant changes in the lattice d-spacing value. We conclude that a fast charging strategy derived from a physics-based model drastically reduces capacity fade and rate of impedance rise in a LCO/graphite smartphone cell as used in this work.

References

1 L. Wang, J. Ma, C. Wang, X. Yu, R. Liu, F. Jiang, X. Sun, A. Du, X. Zhou and G. Cui, Adv. Sci., 2019, 6,
1900355.
2 M. S. Whittingham, Chem. Rev., 2004, 104, 4271–4302.
(Invited) Demystifying the Electrode/Electrolyte Interface in Carbon-Based Electrochemical Capacitors with Specs Technique and Electrochemical Dilatometry
Authors: Fic Krzysztof , Galek Przemyslaw , Menzel Jakub , Bujewska Paulina , Donne Scott W 
Published: December 2020

It is often said that the highly developed surface area of electrode materials ensures high capacitance, power and energy in electrochemical capacitors. However, the real ‘efficiency’ of the surface exploited in charge storage remains unknown. Recently, it turned out that the Step Potential Electrochemical Spectroscopy (SPECS) technique can be a useful tool for determining it.
The SPECS technique allows for the comprehensive analysis of the total current output and evaluation of the capacitive, redox and other components. Together with the physicochemical data from nitrogen and CO2 adsorption techniques, we aim at the determination of the real electrode/electrolyte interface surface.
Based on the knowledge gained to date, we assume that the efficiency of the interface ‘exploitation’ depends on many factors: pore size distribution, wettability of the electrode material by electrolyte, as well as the size of the ions. Thus, inappropriate selection of one of these parameters can aggravate the device performance, even if the excellent carbon material is applied as electrode component.
The paper will provide the results from SPECS correlated with the physicochemical properties of carbon materials. It appears that the electrochemically accessible surface does not exceed 30% of the values estimated by N2 or CO2adsorption. The results will be supported by the recent findings from electrochemical dilatometry experiments.
Carbon Supported PtRu-Ni Ternary Nanoparticles with a PtRu Rich Shell Using a Polydopamine Protective Coating As CO Tolerant Electrocatalyst
Authors: Lee Hojin , Kim Hansung 
Published: December 2020

Carbon supported PtRu-Ni/C catalysts with a Ni-rich core structure are prepared through high temperature treatment of as-prepared polyol PtRu/C catalysts. It is well acknowledged that in conventional PtRu alloys, Ru prevents the adsorption of carbon monoxide on Pt surface via bifunctional mechanism. Also, the ligand effect is known to alter the electron structure of Pt for increased CO tolerance. In this work, the optimal Ni amount is determined for enhanced high resistance to carbon monoxide poisoning. The diffusion of Ni into the core of the catalysts is conducted by controlling the temperature during heat treatment. The as-prepared polyol PtRu/C catalysts have carbonized polydopamine layer on the surface, which prevents particle segregation during high temperature heat treatment. The carbon layer also partakes the role of transferring Ni particles into the core of the catalyst. When compared to using without protective coating method to directly fabricate PtRu-Ni/C catalysts, this method is far more superior. In general, Ni species on the surface is easily to be dissolved in acidic medium in PEMFC. But, PtRu-Ni/C with protective coating, in which Ni species is located inside the bulk of nanoparticles, would prevent it from dissolution in acidic medium while keeping the interaction between Ni and surface Pt.
In this study, Energy-dispersive X-ray spectroscopic line scan profile confirm that the PtRu-Ni/C catalyst has a Ni-rich core and PtRu-rich shell structure. From polymer electrolyte membrane fuel cell tests using CO containing H2 gas, the core-shell structured PtRu-Ni/C alloy formed by protective coating method is demonstrated to have higher tolerance to CO poisoning than PtRu/C catalysts synthesized by polyol method.
Synthesis and Electrocatalytic Activity of Pt-Ni Nanowire
Authors: Iguchi Yoshimi , Li Tianchi , Kato Masaru , Yagi Ichizo 
Published: December 2020

Polymer electrolyte fuel cells (PEFCs) are known as sustainable devices and can produce the electricity with no emission of CO2 gas. The oxygen reduction reaction (ORR) occurs at the cathodes in PEFCs and platinum nanoparticles (NPs) are generally used as an ORR catalyst. Pt on the surface of the catalysts can be oxidatively dissolved under catalytic conditions and then their ORR activity decreases.[1, 2] Because alloying and nanostructuring are known to improve the tolerance of the catalyst to the oxidative dissolution[3], we have studied Pt-Ni nanowires (NWs) as an ORR catalyst.[4] NWs can be expected to show stronger interactions between the Pt surfaces and carbon supports than NPs.[5, 6] However, there is a lack of detailed researches on the durability of NWs.
In this research, we synthesized Pt-Ni NWs, conducted an accelerating durability test (ADT) for the ORR activity and investigated the effect of the ADT on the electronic states of NWs by ex situ X-ray photoelectron spectroscopy (XPS) and in situ Pt L3-edge X-ray absorption spectroscopy (XAS). We also characterized NWs by scanning transmission microscopy (STEM), inductively coupled plasma mass spectrometry (ICP-MS) and powder X-ray diffraction (pXRD). Cyclic and linear sweep voltammograms of NWs showed that the mass activity of the NWs was higher than that of NPs. Interestingly, the mass activity of the NWs increases after the ADT whereas the activity of typical NPs decreases.[7] XPS peaks of the NW catalyst in the Pt 4f region were shifted to the higher binding energy after the ADT, compared to those before the ADT. This result suggests that the d-band center of the surface Pt of the NWs were downshifted after the ADT.[8]
In situ Pt L3-edge XAS revealed that the potential dependence of the intensity of the NW catalyst in the white line region after the ADT is smaller than that of before the ADT. This result suggests that the formation of Pt oxide was suppressed after the ADT,[1] leading to the improvement of the mass activity.

References

[1] K. Nagasawa, et al., J. Am. Chem. Soc., 137, 12856 (2015).
[2] H. Nejc, et al., Acc. Chem. Res., 49, 2015 (2016).
[3] L. Robner et al., ACS Catal.,
9, 2018 (2019).
[4] L. Xhikun, et al., RSC Adv., 10, 6287 (2020).
[5] I. Stephens, et
al., Science, 354, 1378 (2016).
[6] M. Li, et al., Science, 354, 1414 (2016).
[7] G. Mingxing, et al., ACS Catal., 9, 4488 (2019).
[8] M. Wakisaka, et al., J. Phys. Chem. B, 110, 23489 (2006).

Acknowledgements

This work was supported by NEDO.