scholarly journals Overcoming Practical Barriers in Reconditioning Li-Polymer Batteries

2020 ◽  
Vol 71 (4) ◽  
pp. 366-372
Author(s):  
Ioana-Alina Ciobotaru ◽  
Florin-Mihai Benga ◽  
Irina-Elena Ciobotaru ◽  
Danut-Ionel Vaireanu

Abstract. In this paper, two case studies regarding the application of a reconditioning procedure of aged lithium-polymer batteries used to power a notebook and a tablet are presented. The parameters measured in the evaluating the performance of the reconditioned rechargeable batteries are the charging/discharging capacity and the internal resistance. The results obtained indicate a high degree of reconditioning of the investigated batteries, expressed as a reconditioning coefficient, calculated on the basis of the measured nominal capacities after applying the reconditioning procedure with respect to the initial one.

2018 ◽  
Vol 69 (4) ◽  
pp. 851-853
Author(s):  
Florin Mihai Benga ◽  
Danut Ionel Vaireanu ◽  
Ioana Alina Ciobotaru ◽  
Irina Elena Ciobotaru

This paper introduces a method of reconditioning lithium-polymer batteries which are no longer performing as expected. The reconditioning process consists of consecutive charging/discharging steps at controlled currents and is followed by an evaluation procedure, in order to determine the actual performances of the reconditioned batteries. For the evaluation of the characteristics of the Li-polymer batteries, one has measured the charging capacity, the discharging capacity and the internal resistance. However, after the reconditioning stage, one must look for a new application for these batteries, as the reconditioned batteries are seldom behaving as the new ones to be used for the same initial designated application. We manufactured and tested a cold jump-start system, particularly useful in the case of cars flat batteries or cars batteries starting failure. The advantages of this system consist in their reduced mass and volume and a very powerful starting current, comparable to that of high capacity lead acid batteries, the system being able to act as multiple starting aids.


Author(s):  
Tehila Kalagy

For about a decade, ultra-Orthodox and Bedouin women have been applying to higher education academic institutions in Israel in order to study despite bans from their conservative communities. Academic studies instill learning and culture, create an encounter with knowledge for the individual and thus carry a high degree of threat to the rigid conservative enclave. This article examines how conservative societies cope with the wheels of change as the process of higher education for women expands. The case studies in this article are 60 educated women from Jewish ultra-Orthodox society and from Negev Bedouin groups in Israel. As shown by the findings, a theoretical flow model based on three parameters emerges: value-constraint-maneuver. In summary, it appears that this model reflects the development of a new conservative female model that combines traditional values with contemporary indicators.


2018 ◽  
Vol 29 (2) ◽  
pp. 202
Author(s):  
Ott Karulin

In this article the popular is defined with the tools of field theory by Pierre Bourdieu, that is as production with high degree of outer-field economic capital (measured with the number of visits per production). It is also claimed that on some conditions these productions do not lower the degree of autonomy of the field since theatre manages to convert the economic capital to symbolic capital (nominations for annual awards give evidence of the latter). Such a production is called the Full Game. Based on the comparable data of new productions made in Estonia from 2010 to 2015 (1199 in total) the article will introduce a possible methodology of how to calculate the popular in theatre that considers both the number of visits per production in a year and the use of seating capacity. Following that methodology, there were only sixty-one produc­tions during the chosen period that could be titled popular in a sense that they have a very high degree of outer-field success (these productions are visited 2,4 times more often than the average number of visits per production in one calendar year and have the attendance rate of 95% and higher). Taking into account also the inner-field specific consecration (whether they have been nominated for annual theatre awards), only twenty-three popular productions – among them just one comedy, one musical and one operetta – remain in the list of what I have called the Full Game. That is two per cent of all the new productions of the respective time period.The list of Full Games suggests that the specific theatre, where the production is per­formed plays a significant role for a production to become popular. Only four theatres have had more than one Full Game in 2010–15 in Estonia and two of them – Theatre NO99 and Tallinn City Theatre – are used as case studies to find possible strategies of being popular without loosing specific consecration.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ahmed Metwaly ◽  
Ali ElKattan ◽  
Menatalla Kaoud

PurposeThe purpose of the presented research paper is to explore the different aspects of crowdsourcing and its evolution over time. Supported by three different case studies, the research focuses on the different factors that affect crowdsourcing for open innovation. Moreover, the findings give us a proposed managerial framework to be considered when adopting crowdsourcing in addition to factors that proved its huge effect on crowdsourcing activities.Design/methodology/approachA qualitative research approach for this research was the most convenient. It focuses on providing an in-depth understanding of the phenomena. Qualitative research represents the views and perspectives of the participants in a study besides it is driven by a desire to explain these events, through existing or emerging concepts (Yin, 2016). Adopting a case study research method that investigates a contemporary phenomenon (the “case”) in depth and within its real-world context, especially when the boundaries between phenomenon and context may not be evident (Yin, 2018) as in crowdsourcing based business model for open innovation.FindingsThe researchers presented the benefits and challenges when considering crowdsourcing establishing a managerial framework for open innovation. Additionally, the researchers identified the different factors that highly affect crowdsourcing proposing a model that can be used for adopting crowdsourcing. The research also presented insights about how crowdsourcing was introduced in the Egyptian market and how it evolved through the years.Research limitations/implicationsThe study had some limitations to be considered in the following work. Company X used crowdsourcing within a high degree of limitations and confidentially consequently, restricting the effects and results of crowdsourcing. Another limitation was that the study has been only qualitative, and the addition of the quantitative approach will numerically support the findings. Moreover, the research depended on the businesses only as of the source of information and neglected the crowd sample.Practical implicationsThe main aim of this study was to address the lack of research evidence on what it means to adopt crowdsourcing for open innovation in Egyptian firms. The authors have done so by adopting three case studies which enabled them to directly observe and report on the daily work of trust CEOs, with special attention to the practices. Whereby, these executives made themselves knowledgeable for all practical purposes, as dictated by their specific job. Accordingly, the first major contribution of the present research is that it provides much-needed empirical data on the actual practices of crowdsourcing in three Egyptian, yet international companies. Moreover, the results could be used as a guideline when considering crowdsourcing activities highlighting the advantages and disadvantages of such activities.Originality/valueThe paper discusses different perspectives of crowdsourcing presenting a new categorization for its types. Moreover, how these types have been used especially in the Egyptian market. On the other hand, the paper investigated and documented three different sized companies' experiences utilizing crowdsourcing for innovation. The collected information was used to suggest a new model by which companies can avoid the difficulties others had. Moreover, the research highlighted the benefits and challenges of using crowdsourcing for open innovation.


2016 ◽  
Vol 3 ◽  
pp. 100-112 ◽  
Author(s):  
Mitchell Healey ◽  
Julian Lee

Abstract: Powering implantable devices in human body with a glucose based fuel cell (GFC) offers an alternative to non-rechargeable batteries that typically require routine invasive surgery. There are three main approaches for GFCs to oxidise glucose. Enzymatic Fuel Cells are selective and have a high reaction rate but are unstable as the proteins can denature giving the cell a short lifespan. Microbial Fuel Cells use microbes to break down glucose to produce electrons. However they possess the danger of cell leakages that can introduce the microbes to the patient and risk possible infection. Abiotic Fuel Cells employ inorganic catalysts, typically a noble metal alloy or metallic carbon to oxidise and reduce glucose and oxygen respectively. Abiotic is the safest and most stable of the three but possesses the lowest output due to the electrodes inability to target glucose specifically. This meta-study investigates for Abiotic Glucose Fuel Cell being the most viable candidate of the three for possible use in autonomous medical devices. We will assess current abiotic fuel cells on the thermodynamic parameters of output voltage, current/current density, power density and efficiency. The kinetic parameters of internal resistance and rate at which membranes transport electrons will also be assessed. Operational parameters of lifespan and overall architecture will also be assessed to further understand the conditions and materials these cells were produced.Keywords: Glucose; Fuel Cell; Meta-study; Enzymatic; Microbial; Abiotic; Implantable Devices


2014 ◽  
Vol 46 (5) ◽  
pp. 265-269
Author(s):  
Bob Little

Purpose – The purpose of this paper is to outline an unusual – and online-based – approach to sales and negotiation training and coaching. Design/methodology/approach – Interviews with organisations involved, augmented with case studies. Findings – The “Learn, Implement, Support” method of developing sales and negotiating skills is effective. It combats, cost effectively, the criticism that 30 per cent of all learning is forgotten within 30 days of receiving training unless it is reinforced in a practical way. Practical implications – Organisations of all sizes – not just global multinationals – can now increase productivity and profitability from the online delivery of relevant learning materials, followed immediately by virtual coaching and support for a period of at least 12 months. Social implications – People can learn how to sell products and services more effectively and efficiently, via online-delivered learning and coaching, which contains a high degree of video. Originality/value – Organisations of all sizes – not just global multinationals – can now experience and benefit from the knowledge, skills and experience of a master-performer in the fields of sales and negotiation, thanks to the advent of a system of online learning delivery followed by virtual coaching.


2015 ◽  
Vol 15 (10) ◽  
pp. 7611-7614 ◽  
Author(s):  
Seongwoo Ryu ◽  
Byung Gon Kim ◽  
Jang Wook Choi ◽  
Haeshin Lee

Lithium oxygen batteries are one of the next generation rechargeable batteries. High energy density of lithium oxygen batteries have been considered as a very attractive power option for electric vehicles and many other electronic devices. However, they still faced substantial challenges such as short cycle life, large voltage hysteresis, low gravimetric and volumetric power. Here we developed a highly aligned CNT structured sheet for favorable lithium oxygen cathode electrodes. We fabricated highly oriented CNT sheets by rolling vertically aligned CNT arrays. Highly oriented CNT sheets provide excellent electrical conductivity with favorable mesoporous structure for cathode electrode. As a result, the CNT sheet performed maximum discharging capacity of 1810 mA/gc. We found that electrical conductivity and pore distribution plays important rolls for improving performance in lithium oxygen batteries. This study suggests new strategies of designing highly efficient porous carbon electrodes for lithium oxygen batteries.


Author(s):  
Tehila Kalagy

For about a decade, ultra-Orthodox and Bedouin women have been applying to higher education academic institutions in Israel in order to study despite bans from their conservative communities. Academic studies instill learning and culture, create an encounter with knowledge for the individual and thus carry a high degree of threat to the rigid conservative enclave. This article examines how conservative societies cope with the wheels of change as the process of higher education for women expands. The case studies in this article are 60 educated women from Jewish ultra-Orthodox society and from Negev Bedouin groups in Israel. As shown by the findings, a theoretical flow model based on three parameters emerges: value-constraint-maneuver. In summary, it appears that this model reflects the development of a new conservative female model that combines traditional values with contemporary indicators.


1931 ◽  
Vol 4 (2) ◽  
pp. 264-272
Author(s):  
J. McGavack ◽  
J. S. Rumbold

Abstract The pH of latex has been determined at various concentrations of ammonia (1) by the use of indicators, and (2) by the application of the glass electrode. The two curves thus obtained were comparable but not identical. It is shown that the glass electrode gives results reproducible with a high degree of accuracy up to pH 9.5 and a fair degree of accuracy up to pH 11.0. Above pH 11.0 it is necessary to calibrate each electrode. An ordinary galvanometer allowed measurement of the e. m. f. to 1 millivolt. The assymetry of the glass was so small as to be negligible. This paper covers the work done so far in these laboratories on the development of an accurate and rapid method for determining the pH of latex. From a practical viewpoint one of the most troublesome features of the direct use of a hydrogen electrode is the deposition of a film of rubber on the platinum, which by increasing the internal resistance of the cell, so reduces the sensitivity of the null point instrument that after a few determinations the apparatus must become inoperative. A more serious objection to this electrode is the uncertainty attached to measurements made in solutions containing proteins.


Sign in / Sign up

Export Citation Format

Share Document