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1.
Data Brief ; 52: 109798, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38076480

ABSTRACT

The data reported here was prepared to study the effects of calendering process on NMC622 cathodes using a 3-3-2 full factorial design of experiments. The data set consists of 18 unique combinations of calender roll temperature (85 °C, 120 °C, or 145 °C), electrode porosity (30%, 35%, or 40%), and electrode mass loading (120 g/m² or 180 g/m²). The reported physical characteristics of the electrodes include thickness, coating weight, maximum tensile strength, and density. The electrochemical performances of the electrodes were obtained by testing coin cells. In this context, 54 half-cells were produced, 3 per each calendering experiment to ensure repeatability and reliability of the results. The responses of interest included, charge energy capacity at C/2, C/5, discharge energy capacity at C/20, C/5, C/2, C, 2C, 5C, 10C, gravimetric capacity (charge at C/2, C/5, discharge at C/20, C/5, C/2, C, 2C, 5C, 10C), volumetric capacity (charge at C/2, C/5, discharge at C/20, C/5, C/2, C, 2C, 5C, 10C), rate performance (5C:0.2C), area specific impedance (at 10% to 90% state of charge (SoC) in 10 breakpoints), long-term cycling capacity (charge at C/5 for 50 cycles, discharge at C/2 for 50 cycles), long-term cycling degradation (at C/2 during 50 cycles of charge and discharge), and cycling columbic efficiency (50 cycles of C/2 charge and discharge). The details of the experimental design that has led to this data as well as comprehensive statistical analysis, and machine learning-based models can be found in the recently published manuscripts by Hidalgo et al. and Faraji-Niri et al. [1,2].

2.
Phys Chem Chem Phys ; 24(48): 29999-30009, 2022 Dec 14.
Article in English | MEDLINE | ID: mdl-36472147

ABSTRACT

Join counting, a standard technique in spatial autocorrelation analysis, has been used to quantify the clustering of carbon, fluorine and sodium in cross-sectioned anode and cathode samples. The sample preparation and EDS mapping steps are sufficiently fast for every coating from two Design of Experiment (DoE) test matrices to be characterised. The results show two types of heterogeneity in material distribution; gradients across the coating from the current collector to the surface, and clustering. In the cathode samples, the carbon is more clustered than the fluorine, implying that the conductive carbon component is less well distributed than the binder. The results are correlated with input parameters systematically varied in the DoE e.g. coating blade gap, coating speed, and other output parameters e.g. coat weight, and electrochemical resistance.

3.
Data Brief ; 40: 107720, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34988274

ABSTRACT

Megtec Systems pilot-plant scale continuous convective coater. The data was generated as part of an experimental design involving the following coating-drying process variables and ranges: comma bar gap, 80-140 µm; web speed, 0.5-1.5 m/min; coating ratio, 110-150%; drying temperature, 85-110 °C and drying air speed, 5-15 m/s. The manufacturing data include pre-calendered coating thickness, mass loading dry and wet, pre-calendered porosity, spatial autocorrelation and join counting (SAJC) Z-score for carbon and for fluorine, cell thickness, coating weight and porosity of 15 different electrode coatings and 45 half-coin cells. The electrochemical data was obtained at 25 °C in a Maccor 4000 series battery cycler and consists of charge and discharge capacities at C/20, C/5, C/2, 1C, 2C, 5C and 10C C-rates. Discharge gravimetric and volumetric capacities, rate performance (at 5C:0.2C) and first cycle loss data is also reported. Details of the experimental design and a comprehensive analysis of the data can be found in the co-submitted manuscript (Román-Ramírez et al., 2021). Additional collected data not used in Román-Ramírez et al. (2021) is reported in the present manuscript and include visual observations of coating defects, rheological properties of the electrode slurries (solid content, viscosity, coating shear rate and viscosity at coating shear rate), room temperature and room humidity during the coatings and first cycle loss of the coin cells. Raw and analyzed data is made available. The reported data can be used to extend the analysis reported in Román-Ramírez et al. (2021), and for the comparison of relevant data obtained at different manufacturing scales.

4.
Technol Innov ; 22(1): 65-73, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-34707797

ABSTRACT

Clinicians and staff of the Department of Veterans Affairs Health Care System (VA), who provide services to veterans, have invented many devices and methods for improving veterans' lives. However, translating those inventions to the market has been a challenge due to limited collaboration between the clinical inventors and the scientists, researchers, and engineers who can produce the prototypes necessary for licensing the technology. The VA Technology Transfer Program office and the Human Engineering Research Laboratories, a research laboratory with experience with developing prototypes and licensing technology, jointly developed a program called the Technology Transfer Assistance Project (TTAP) to bridge the gap between clinical inventors and prototypes ready for licensing. This paper describes TTAP and provides examples of the first inventions that were developed or enhanced through TTAP.

5.
Technol Innov ; 22: 173-179, 2021 Dec 15.
Article in English | MEDLINE | ID: mdl-35096277

ABSTRACT

The COVID-19 pandemic stressed healthcare systems all over the world. Two primary challenges that healthcare systems faced were a shortage of personal protective equipment and the need for new technologies to handle infection prevention for staff and patients. The Department of Veteran's Affairs (VA) Technology Transfer Program responded by prioritizing the development of innovations in the Technology Transfer Assistance Project which addressed the pandemic. This paper describes several innovations that addressed the needs of the VA healthcare system during the pandemic and how they were rapidly developed.

6.
Sci Rep ; 8(1): 1386, 2018 01 23.
Article in English | MEDLINE | ID: mdl-29362384

ABSTRACT

Silicon-Few Layer Graphene (Si-FLG) composite electrodes are investigated using a scalable electrode manufacturing method. A comprehensive study on the electrochemical performance and the impedance response is measured using electrochemical impedance spectroscopy. The study demonstrates that the incorporation of few-layer graphene (FLG) results in significant improvement in terms of cyclability, electrode resistance and diffusion properties. Additionally, the diffusion impedance responses that occur during the phase changes in silicon is elucidated through Staircase Potentio Electrochemical Impedance Spectroscopy (SPEIS): a more comprehensive and straightforward approach than previous state-of-charge based diffusion studies.

7.
Disabil Rehabil Assist Technol ; 12(8): 843-851, 2017 11.
Article in English | MEDLINE | ID: mdl-28129705

ABSTRACT

Purpose of state: The aims of this study were to develop a Wheelchair Maintenance Training Programme (WMTP) as a tool for clinicians to teach wheelchair users (and caregivers when applicable) in a group setting to perform basic maintenance at home in the USA and to develop a Wheelchair Maintenance Training Questionnaire (WMT-Q) to evaluate wheelchair maintenance knowledge in clinicians, manual and power wheelchair users. METHODS: The WMTP and WMT-Q were developed through an iterative process. RESULTS: A convenience sample of clinicians (n = 17), manual wheelchair (n ∞ 5), power wheelchair users (n = 4) and caregivers (n = 4) provided feedback on the training programme. A convenience sample of clinicians (n = 38), manual wheelchair (n = 25), and power wheelchair users (n = 30) answered the WMT-Q throughout different phases of development. The subscores of the WMT-Q achieved a reliability that ranged between ICC(3,1) = 0.48 to ICC(3,1) = 0.89. The WMTP and WMT-Q were implemented with 15 clinicians who received in-person training in the USA using the materials developed and showed a significant increase in all except one of the WMT-Q subscores after the WMTP (p < 0.007). CONCLUSION: The WMTP will continue to be revised as it is further implemented. The WMT-Q is an acceptable instrument to measure pre- and post-training maintenance knowledge. Implications for Rehabilitation The Wheelchair Maintenance Training Program can be used to educate rehabilitation clinicians and technicians to improve wheelchair service and delivery to end users. This training complements the World Health Organization basic wheelchair service curriculum, which only includes training of the clinicians, but does not include detailed information to train wheelchair users and caregivers. This training program offers a time efficient method for providing education to end users in a group setting that may mitigate adverse consequences resulting from wheelchair breakdown. This training program has significant potential for impact among wheelchair users in areas where access to repair services is limited.


Subject(s)
Disabled Persons/rehabilitation , Health Personnel/education , Maintenance/methods , Patient Education as Topic/methods , Wheelchairs , Caregivers , Electric Power Supplies , Health Personnel/standards , Humans , Inservice Training , Knowledge , Patient Education as Topic/standards , Reproducibility of Results
8.
Phys Chem Chem Phys ; 18(44): 30677-30685, 2016 Nov 09.
Article in English | MEDLINE | ID: mdl-27790666

ABSTRACT

Hybrid anode materials consisting of micro-sized silicon (Si) particles interconnected with few-layer graphene (FLG) nanoplatelets and sodium-neutralized poly(acrylic acid) as a binder were evaluated for Li-ion batteries. The hybrid film has demonstrated a reversible discharge capacity of ∼1800 mA h g-1 with a capacity retention of 97% after 200 cycles. The superior electrochemical properties of the hybrid anodes are attributed to a durable, hierarchical conductive network formed between Si particles and the multi-scale carbon additives, with enhanced cohesion by the functional polymer binder. Furthermore, improved solid electrolyte interphase (SEI) stability is achieved from the electrolyte additives, due to the formation of a kinetically stable film on the surface of the Si.

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