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Title: Electrochemical intercalation of lithium-ion into carbon fibers prepared from synthetic cellulose precursor.
Creator: Kashauer, Robert Lewis., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A number of fibrous carbon materials have been investigated as intercalation host materials. Commercially available rayon fiber (synthetic cellulose) based carbon fibers were synthesized for use as anode material in lithium-ion batteries. The effects of oxidation and carbonization temperature, heating ramp rate, soak time and gaseous atmosphere during thermal treatment on the electrochemical performance of the carbon fibers were studied. Intercalation/deintercalation experiments were...
Show moreA number of fibrous carbon materials have been investigated as intercalation host materials. Commercially available rayon fiber (synthetic cellulose) based carbon fibers were synthesized for use as anode material in lithium-ion batteries. The effects of oxidation and carbonization temperature, heating ramp rate, soak time and gaseous atmosphere during thermal treatment on the electrochemical performance of the carbon fibers were studied. Intercalation/deintercalation experiments were performed to evaluate the electrochemical performance of the carbon fibers. The highest reversible capacity and lowest irreversible capacity loss were obtained for carbon fibers carbonized at 1100C at a ramp rate of 10C/min held at soak times of 1 and 5 hours. Electrolyte containing 1M LiPF6 in 70/30 v/o EC:DMC proved to be most suitable for these carbon fiber materials. The influence of electrolyte composition (solvent and salt) on the reversible and irreversible capacities as well as on the intercalation/deintercalation potential profile were also studied.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15452
Subject Headings: Carbon fibers, Lithium cells, Electrolytes
Format: Document (PDF)

Title: Effect of strain rate and temperature on the stress corrosion cracking tendency of engineering alloys in acidified seawater.
Creator: Kundalgurki, Srivatsa G., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The stress corrosion cracking (SCC) tendencies of several engineering alloys were studied in an acidified seawater environment as a function of applied strain rate and electrolyte temperature. The selected alloys included austenitic stainless steels 304L, 316L, 904L and A-286 (an iron-based superalloy at two heat treatments yielding ultimate tensile strengths of 130 and 200 ksi), Inconel 718 (220 ksi ultimate tensile strength) and Hastelloys C-22 and C-276. The slow strain rate test technique...
Show moreThe stress corrosion cracking (SCC) tendencies of several engineering alloys were studied in an acidified seawater environment as a function of applied strain rate and electrolyte temperature. The selected alloys included austenitic stainless steels 304L, 316L, 904L and A-286 (an iron-based superalloy at two heat treatments yielding ultimate tensile strengths of 130 and 200 ksi), Inconel 718 (220 ksi ultimate tensile strength) and Hastelloys C-22 and C-276. The slow strain rate test technique was used to evaluate the SCC strain rate dependency of each alloy at extension rates of 4.7 x 10^-6, 4.7 x 10^-4 and 4.7 x 10^-3 mm/sec. The effect of electrolyte temperature was evaluated at 38C and 60C at a single extension rate of 4.7 x 10^-5 mm/sec. Control specimens were tested in a laboratory air environment at an extension rate of 4.7 x 10^-5 mm/sec. Various mechanical parameters of the specimens tested in the corrosive medium were compared with those of control specimens to quantify the degree of cracking. Fractographic evidence of SCC was obtained using scanning electron microscopy (SEM). An attempt was made to correlate SCC tendency with the alloy's passivation kinetics and microstructure. Atmospheric exposure testing was performed in a simulated space shuttle launch pad environment for selected alloys.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14853
Subject Headings: Alloys--Stress corrosion, Stress corrosion, Sea-water corrosion
Format: Document (PDF)

Title: Fabrication and characterization of copper/molybdenum coatings on carbon fibers by electrodeposition.
Creator: Maucione, Luke J., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The codeposition of a smooth and uniform coating of copper and molybdenum was successfully achieved on T-650 carbon fiber. The effect of various plating parameters on the electrodeposition of copper and molybdenum such as plating bath chemistry, current density, and pulse frequency were studied. By adjusting the aforementioned variables, qualitative and quantitative analysis was conducted to evaluate the deposit smoothness, uniformity, and wetting characteristics. Qualitative analysis of the...
Show moreThe codeposition of a smooth and uniform coating of copper and molybdenum was successfully achieved on T-650 carbon fiber. The effect of various plating parameters on the electrodeposition of copper and molybdenum such as plating bath chemistry, current density, and pulse frequency were studied. By adjusting the aforementioned variables, qualitative and quantitative analysis was conducted to evaluate the deposit smoothness, uniformity, and wetting characteristics. Qualitative analysis of the deposits were made using scanning electron microscopy and energy dispersive spectroscopy. Quantitative analysis of the deposit coating was conducted using inductively coupled plasma chemical analysis, dewetting tests, X-ray diffraction, transmission electron microscopy, and auger electron spectroscopy. Based on the results, a plating line was designed and constructed for the continuous deposition of copper and molybdenum onto carbon fiber tows.
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Date Issued: 1995
PURL: http://purl.flvc.org/fcla/dt/15124
Subject Headings: Composite materials, Alloy plating, Metallic composites, Molybdenum alloys
Format: Document (PDF)

Title: CVD synthesis of carbon nanotubes as active materials for electrochemical capacitors.
Creator: Merritt, Ryan Patrick., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Results are reported on a method to synthesize multi-wall carbon Nanotubes (MWNTs) using a liquid injection chemical vapor deposition (CVD) method centered around ferrocene as the catalyst precursor. These materials were specifically targeted as active materials for electrochemical double layer capacitors (EDLCs). A parameteric study was developed to optimize material synthesis based on growth parameters, characterize physical growth properties, and evaluate the performance of the MWNTs as...
Show moreResults are reported on a method to synthesize multi-wall carbon Nanotubes (MWNTs) using a liquid injection chemical vapor deposition (CVD) method centered around ferrocene as the catalyst precursor. These materials were specifically targeted as active materials for electrochemical double layer capacitors (EDLCs). A parameteric study was developed to optimize material synthesis based on growth parameters, characterize physical growth properties, and evaluate the performance of the MWNTs as electrodes in electrochemical capacitors. Physical data includes scanning electron micrographs (SEM), transmission electron micrographs (TEM), and x-ray powder diffraction (XRD). Electrochemical performance data is given based on cyclic voltammetry (CV) and impedance spectroscopy (EIS).
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Date Issued: 2003
PURL: http://purl.flvc.org/fcla/dt/13037
Subject Headings: Chemical vapor deposition, Electric double layer, Electrolytic capacitors, Nanotubes
Format: Document (PDF)

Title: Lithium intercalation into PAN-based carbon fiber materials.
Creator: Nechev, Kamen S., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: High energy density PAN-based carbon fiber anode materials for lithium-ion type batteries were developed. Commercially available organic precursors were thermally converted to carbons. The effects of precursor material, carbonization temperature, heating ramp rate, soak time and gaseous atmosphere during the thermal treatment on the electrochemical performance of the carbon fibers were studied. In order to evaluate the electrochemical performance of the carbon fibers, test cells were assemble...
Show moreHigh energy density PAN-based carbon fiber anode materials for lithium-ion type batteries were developed. Commercially available organic precursors were thermally converted to carbons. The effects of precursor material, carbonization temperature, heating ramp rate, soak time and gaseous atmosphere during the thermal treatment on the electrochemical performance of the carbon fibers were studied. In order to evaluate the electrochemical performance of the carbon fibers, test cells were assemble using the carbon materials prepared in the laboratory and intercalation/deintercalation experiments were performed. The results indicated that the highest reversible capacity and lowest irreversible capacity loss was obtained for carbon fibers carbonized at 1100C at fast ramp rate of 26C/min. X-ray diffraction experiments revealed a relation between the capacity and the irreversible capacity loss on first cycle, and the size of the crystallites Lc. A phenomenological explanation for this behavior was developed. Using electrochemical impedance spectroscopy the diffusion coefficient of Li in the tested carbon fibers was calculated. In addition, the influence of electrolyte composition (solvent and salt) on the reversible and irreversible capacities as well as on the intercalation/deintercalation potential profile was investigated. An electrolyte containing 1M LiPF6 in EC:DEC:DMC (40:30:30 v/o) proved to be most suitable for these carbon fiber materials improving significantly their electrochemical performance. Finally, coin cells were assembled containing the carbon fiber material prepared in the laboratory. They were tested for reversible and irreversible capacity. The coin cells proved that the synthesized carbon anode materials possess high energy density and could be used in commercial applications.
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Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/12471
Subject Headings: Lithium cells, Carbon fibers, Electric batteries
Format: Document (PDF)

Title: Electrochemical impedance spectroscopy of nickel-hydrogen and silver oxide-metal hydride secondary batteries.
Creator: Nechev, Kamen S., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Full nickel-hydrogen (Ni-H2) boilerplate batteries were cycled and impedance measurements were made at different states-of-charge (SOC), electrolyte concentrations and charge/discharge rates. Experiments were conducted on cells containing new and cycled (11,000 cycles) electrodes. Additionally, an EIS study of Ni-H2 flightweight IPV satellite cells was performed. A number of experiments were conducted on silver oxide-metal hydride batteries. The interest was focused on both negative and...
Show moreFull nickel-hydrogen (Ni-H2) boilerplate batteries were cycled and impedance measurements were made at different states-of-charge (SOC), electrolyte concentrations and charge/discharge rates. Experiments were conducted on cells containing new and cycled (11,000 cycles) electrodes. Additionally, an EIS study of Ni-H2 flightweight IPV satellite cells was performed. A number of experiments were conducted on silver oxide-metal hydride batteries. The interest was focused on both negative and positive electrodes and upon the system itself. This work was preliminary and aided in describing the general performance of the battery. For analysis, the data was fitted to an equivalent electrical circuit using the Nonlinear Least Squares Method (NLSM). The correlation between theoretical and empirical data was sufficiently good.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/14958
Subject Headings: Nickel-hydrogen batteries, Electrodes, Nickel, Impedance spectroscopy, Electrochemical analysis, Electric batteries--Electrodes
Format: Document (PDF)

Title: Characterization of nickel electrodes for secondary batteries by means of electrochemical impedance spectroscopy.
Creator: Nenov, Krassimir Petrov., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: An automated procedure for integrated cycling and electrochemical impedance spectroscopy (EIS) testing of nickel sinter individualized pressure vessel electrodes for secondary nickel/hydrogen batteries was developed. Nickel electrodes from three major U.S. manufacturers were cycled under various conditions. The condition of the electrodes was monitored using both EIS and traditional electrochemical methods. In order to establish relationships between the status of the electrodes and the...
Show moreAn automated procedure for integrated cycling and electrochemical impedance spectroscopy (EIS) testing of nickel sinter individualized pressure vessel electrodes for secondary nickel/hydrogen batteries was developed. Nickel electrodes from three major U.S. manufacturers were cycled under various conditions. The condition of the electrodes was monitored using both EIS and traditional electrochemical methods. In order to establish relationships between the status of the electrodes and the acquired impedance spectra, various cycling and electrode parameters were analyzed and compared with the EIS data. Nonlinear least squares (NLS) regression was used for analysis of the impedance data. An equivalent circuit was developed which produced good correlation with the impedance data at all states-of-charge and discharge rates. Problems with the experimental procedure which limit the validity of EIS testing were discussed.
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Date Issued: 1991
PURL: http://purl.flvc.org/fcla/dt/14777
Subject Headings: Impedance spectroscopy, Electrochemical analysis, Electric batteries--Electrodes
Format: Document (PDF)

Title: Environmental cracking susceptibility of austenitic stainless steel alloys in acidified seawater.
Creator: Poulassichidis, Antonios N., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The stress corrosion cracking susceptibility of austenitic stainless steels SS304L, SS316L and SS904L was studied in an acidified seawater environment by slow strain rate testing at 24, 38 and 66$\sp\circ$C. Fractographic evidence of SCC susceptibility was obtained using scanning electron microscopy. The degree of susceptibility to SCC for each alloy in these environments is discussed based on the mechanical parameters, fractography and anodic polarization behavior. The results showed that...
Show moreThe stress corrosion cracking susceptibility of austenitic stainless steels SS304L, SS316L and SS904L was studied in an acidified seawater environment by slow strain rate testing at 24, 38 and 66$\sp\circ$C. Fractographic evidence of SCC susceptibility was obtained using scanning electron microscopy. The degree of susceptibility to SCC for each alloy in these environments is discussed based on the mechanical parameters, fractography and anodic polarization behavior. The results showed that SS904L performed better than SS304L and SS316L in the aforementioned environments.
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Date Issued: 1994
PURL: http://purl.flvc.org/fcla/dt/15071
Subject Headings: Stress corrosion, Seawater corrosion, Alloys--Stress corrosion
Format: Document (PDF)

Title: Electrochemical double-layer capacitors utilizing low surface area graphite fibers.
Creator: Zawacki, David Isaiah., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Electrochemical double-layer capacitors were constructed using low surface area carbon fibers that are commercially available. The fibers were made from polyacrylonitrile (PAN) and pitch and vary from low (LC = 14A, d002 = 3.54A) to high (LC = 169A, d002 = 3.40A) crystallinity. High energy densities (up to 7.83 Wh/kg) were obtained by electrochemically intercalating HSO4- ions between the graphene planes of the carbon fibers. The intercalation process was strongly influenced by the...
Show moreElectrochemical double-layer capacitors were constructed using low surface area carbon fibers that are commercially available. The fibers were made from polyacrylonitrile (PAN) and pitch and vary from low (LC = 14A, d002 = 3.54A) to high (LC = 169A, d002 = 3.40A) crystallinity. High energy densities (up to 7.83 Wh/kg) were obtained by electrochemically intercalating HSO4- ions between the graphene planes of the carbon fibers. The intercalation process was strongly influenced by the crystallinity of the carbon fiber and by the precursors from which the fiber was manufactured. All the pitch fibers had a higher structural order and a higher carbon content than the PAN fibers. A total of 10 capacitors were constructed. Nine of these were constructed from fibers that were electrochemically activated and one was constructed from fiber as received. 38 w/o sulfuric acid was used as the electrolyte for each of these capacitors. Performance of the capacitors decreased as the structural order and carbon content of the fibers decreased.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15427
Subject Headings: Capacitors, Electric double layer, Graphite fibers
Format: Document (PDF)

Alloys--Stress corrosion (2)	+ -
Carbon fibers (2)	+ -
Electric batteries--Electrodes (2)	+ -
Electric double layer (2)	+ -
Electrochemical analysis (2)	+ -

Impedance spectroscopy (2)	+ -
Lithium cells (2)	+ -
Stress corrosion (2)	+ -
Alloy plating (1)	+ -
Capacitors (1)	+ -
Chemical vapor deposition (1)	+ -
Composite materials (1)	+ -
Electric batteries (1)	+ -
Electrodes, Nickel (1)	+ -
Electrolytes (1)	+ -
Electrolytic capacitors (1)	+ -
Graphite fibers (1)	+ -
Metallic composites (1)	+ -
Molybdenum alloys (1)	+ -
Nanotubes (1)	+ -
Nickel-hydrogen batteries (1)	+ -
Sea-water corrosion (1)	+ -
Seawater corrosion (1)	+ -

College of Engineering and Computer Science (9)	+ -
Florida Atlantic University (9)	+ -
Nechev, Kamen S. (2)	+ -
Kashauer, Robert Lewis. (1)	+ -
Kundalgurki, Srivatsa G. (1)	+ -

Maucione, Luke J. (1)	+ -
Merritt, Ryan Patrick. (1)	+ -
Nenov, Krassimir Petrov. (1)	+ -
Poulassichidis, Antonios N. (1)	+ -
Zawacki, David Isaiah. (1)	+ -

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