scholarly journals Use of Natural Graphite for an Energy Storage Device

2018 ◽  
Vol 1 (1) ◽  
pp. 52
Author(s):  
P. D. D Dilhani ◽  
K. S. Perera ◽  
K. P. Vidanapathirana ◽  
K. Vignarooban

<p><em>Ever growing high concerns over use of safe and low cost devices have provided a substantial attention on natural materials. As such natural graphite which has been deeply integrated into numerous applications is being received a consideration to be used for electrochemical devices. The main objective of this study is to explore the suitability of Sri Lankan natural graphite to serve in electrochemical double layer capacitors (EDLCs). In order to uplift the safety of the device, a gel polymer electrolyte was used instead of a liquid electrolyte. Two identical electrodes were consisted with Sri Lankan natural graphite as the active material and polyvinylidenefluoride as the binder. To prepare the electrolyte, polyvinylidenefluoride co hexafluoropropylene and magnesium perchlorate were used as the polymer and the salt respectively. Cyclic voltammetry test results show that single electrode specific capacitance is depending on the potential window. The percentage reduction of capacitance with continuous cycling was about 28%. Nyquist plot of EDLC further confirm the capacitive nature at low frequency.</em><em></em></p>

2021 ◽  
Author(s):  
Dinithi S. K. Rajaguru ◽  
Kamal Vidanapathirana ◽  
Kumudu S. Perera

Abstract The scientific focus has been directed through the production and application of ‘wonder material- graphene’ after its discovery in 2004. But the mass production cost has become a huge disadvantage towards commercializing graphene based manufactures. As alternative low cost material, exfoliated graphite (EG) has emerged to be a novel nanostructured carbon material with a potential for electrochemical energy storage device applications owed to its unique characteristics similar to graphene. In this study a series of EG samples were prepared by a surfactant mediated liquid phase exfoliation method by changing the exfoliation time. Electrochemical double layer capacitors (EDLCs) were fabricated using different EG samples as an electrode material and a gel polymer electrolyte (GPE). They were characterized by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and galvanostatic charge discharge (GCD) techniques. EDLC having EG electrodes of 10 h exfoliation time showed the highest results with single electrode specific capacitance (Csc) of 4.12 F g− 1, single electrode specific discharge capacitance (Csd) of 1.10 F g− 1 and relaxation time of 0.22 s from CV, GCD and EIS respectively.


Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2760 ◽  
Author(s):  
Mao-Chia Huang ◽  
Cheng-Hsien Yang ◽  
Chien-Chih Chiang ◽  
Sheng-Cheng Chiu ◽  
Yun-Feng Chen ◽  
...  

In recent years, novel Al secondary batteries with Al anodes, natural graphite cathodes, and ionic liquid electrolytes have received more attention. However, most research on Al secondary batteries used lower graphite loading (<8 mg/cm2), which will inhibit the batteries from commercialization in the future. Here, we prepared Al secondary batteries using Al anode, low-cost natural graphite cathode, and cheaper ionic liquid electrolyte. The effects of loading (7–12 mg/cm2) on performance were investigated. Based on our observations, graphite-based Al secondary batteries (GABs) using 10 mg/cm2 graphite electrodes had better performance of 82 mAh/g and 6.5 Wh/L at a current density of 100 mA/g. Moreover, the 10 mg/cm2 GABs showed a long life of 250 charge–discharge cycles with a high coulombic efficiency of 98% and excellent performance rate up to 1000 mA/g.


Author(s):  
Zhidong Liu ◽  
Xiaohang Wang ◽  
Zhiyuan Liu ◽  
Shuqing Zhang ◽  
Zichuan Lv ◽  
...  

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Persona Paolo ◽  
Valeri Ilaria ◽  
Zarantonello Francesco ◽  
Forin Edoardo ◽  
Sella Nicolò ◽  
...  

Abstract Background During COVID-19 pandemic, optimization of the diagnostic resources is essential. Lung Ultrasound (LUS) is a rapid, easy-to-perform, low cost tool which allows bedside investigation of patients with COVID-19 pneumonia. We aimed to investigate the typical ultrasound patterns of COVID-19 pneumonia and their evolution at different stages of the disease. Methods We performed LUS in twenty-eight consecutive COVID-19 patients at both admission to and discharge from one of the Padua University Hospital Intensive Care Units (ICU). LUS was performed using a low frequency probe on six different areas per each hemithorax. A specific pattern for each area was assigned, depending on the prevalence of A-lines (A), non-coalescent B-lines (B1), coalescent B-lines (B2), consolidations (C). A LUS score (LUSS) was calculated after assigning to each area a defined pattern. Results Out of 28 patients, 18 survived, were stabilized and then referred to other units. The prevalence of C pattern was 58.9% on admission and 61.3% at discharge. Type B2 (19.3%) and B1 (6.5%) patterns were found in 25.8% of the videos recorded on admission and 27.1% (17.3% B2; 9.8% B1) on discharge. The A pattern was prevalent in the anterosuperior regions and was present in 15.2% of videos on admission and 11.6% at discharge. The median LUSS on admission was 27.5 [21–32.25], while on discharge was 31 [17.5–32.75] and 30.5 [27–32.75] in respectively survived and non-survived patients. On admission the median LUSS was equally distributed on the right hemithorax (13; 10.75–16) and the left hemithorax (15; 10.75–17). Conclusions LUS collected in COVID-19 patients with acute respiratory failure at ICU admission and discharge appears to be characterized by predominantly lateral and posterior non-translobar C pattern and B2 pattern. The calculated LUSS remained elevated at discharge without significant difference from admission in both groups of survived and non-survived patients.


RSC Advances ◽  
2017 ◽  
Vol 7 (51) ◽  
pp. 32288-32293 ◽  
Author(s):  
Chen Wang ◽  
Junfeng Li ◽  
Handong Jiao ◽  
Jiguo Tu ◽  
Shuqiang Jiao

A novel Al-ion battery based on an Al alloy anode, pyrolytic graphite paper cathode, and low-cost AlCl3–urea liquid analogue electrolyte was successfully established. The present Al alloy/PG battery can afford a capacity as high as 105 mA h g−1.


Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3721 ◽  
Author(s):  
Usman Rashid ◽  
Imran Niazi ◽  
Nada Signal ◽  
Denise Taylor

Texas Instruments ADS1299 is an attractive choice for low cost electroencephalography (EEG) devices owing to its low power consumption and low input referred noise. To date, there have been no rigorous evaluations of its performance. In this EEG experimental study we evaluated the performance of the ADS1299 against a high quality laboratory-based system. Two self-paced lower limb motor tasks were performed by 22 healthy participants. Recorded power across delta, theta, alpha, and beta EEG bands, the power ratio across the motor tasks, pre-movement noise, and signal-to-noise ratio were obtained for evaluation. The amplitude and time of the negative peak in the movement-related cortical potentials (MRCPs) extracted from the EEG data were also obtained. Using linear mixed models, no statistically significant differences (p > 0.05) were found in any of these measures across the two systems. These findings were further supported by evaluation of cosine similarity, waveform differences, and topographic maps. There were statistically significant differences in MRCPs across the motor tasks in both systems. We conclude that the performance of the ADS1299 in combination with wet Ag/AgCl electrodes is analogous to that of a laboratory-based system in a low frequency (<40 Hz) EEG recording.


Sign in / Sign up

Export Citation Format

Share Document