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Nationa Medical Commission (NMC) had recently undertook the revision of Undergraduate CBME curriculum. the Authors were involved in Psychiatry curriculum revision. In this paper,authors explain the process of revision, the rationale behind the changes made and make specific suggestions for the better implementation of the revised curriculum. [ABSTRACT FROM AUTHOR]

State‐of‐the‐art ternary layered oxide cathode active materials in Li‐ion batteries (LIBs) consist of polycrystalline (PC), i.e., micron‐sized secondary particles, which in turn consist of numerous nanosized primary particles. Recent approaches to develop single crystals (SCs), i.e., single and separated micron‐sized primary particles, appear promising in terms of cycle life given their mechanical stability. However, a direct and systematic ("fair") comparison of SC with PC in LIB cell application remains a challenge due to both differences on material level and state‐of‐charge (SoC), as SCs typically have slightly lower delithiation capacities/Li+ extraction ratios. In this work, PC and SC Li[Ni0.8Mn0.1Co0.1]O2 (NMC811) are synthesized with comparable bulk and surface characteristics from identical self‐synthesized precursors. Indeed, the cycle life of SCs is not only superior, when conventionally charged to equal upper cutoff voltage (UCV), as shown in NMC||Li and NMC||graphite cells, but also after adjusting UCVs to similar SoCs, where bigger SCs counterintuitively have even a better rate performance and cycle life. [ABSTRACT FROM AUTHOR]

Summary: Over a long time, different methods of frequency compensation of multistage amplifiers have been exploited for improvement in the behavior of stabilizing. In the present paper, the step‐by‐step conversion process of the dual active capacitive feedback compensation (DACFC) three‐stage amplifier into the nested Miller compensation (NMC) three‐stage amplifier is presented by a systematic approach and signal flow graphs (SFGs) based on the graph theory rules in graph domain. Also, according to graph rules, the conversion of the multiple feedback amplifier NMC into the multiple feedback amplifier DACFC is investigated in detail in the graph domain. During the conversion process, the difference in the gain‐bandwidth product (GBW) in the two mentioned case study's amplifiers is examined in terms of the graph at the system level. The elimination of two branches in one step of the conversion process of the SFG of the NMC into the SFG of the DACFC leads to a significant improvement in the behavior of GBW. This paper also conducts verification of the design of conventional NMC and DACFC amplifier circuits in HSPICE using 0.35‐μm CMOS technology and compares the circuit simulation results to SFG simulation results. In order to show the correctness of the idea, they are redesigned in HSPICE using 0.18‐μm CMOS technology, and appropriate results are obtained. [ABSTRACT FROM AUTHOR]

Background: The Family Adoption Program (FAP), newly mandated by National Medical Commission for all MBBS students aims to provide an experiential learning opportunity for them towards community-based health care. This study was conducted to assess the profile of the MBBS students, their perception and of the families adopted by them on FAP. Materials and Methods: A cross-sectional study was conducted in 2023 including 100 medical students of Rajiv Gandhi Medical College. After sensitization to the FAP proforma, each student was allotted five families for adoption from the Lokmanya Nagar located in the outskirts of Thane city. Students recorded details of families in the proforma. Feedback and perception on FAP from the families as well as from students were collected. The data was analyzed using Microsoft Excel. ꭓ2 test was applied. Results: Out of 100 students, 48% students were males and 52% were females. 96% students were in the age group of 17-20 years and 4% were of aged >20 years. 98% of the medical students were told by the adopted families that FAP is a good initiative. All the students mentioned in the feedback, FAP will help to develop leadership skill among them, will help to enhance the health of the adopted families and will surely improve the communication skill of the Indian Medical Graduates which will be useful for their professional growth. Conclusions: All students were delighted and gratified with this program and the same was mentioned by them in the feedback. FAP will create a significant difference in medical education and will definitely help to promote health of the adopted families.

Ceramic saggars of mullite‐cordierite are currently used to produce cathode powders for lithium‐ion batteries. Strong interactions occur between the LiNi0.8Mn0.1Co0.1O2 (NMC) precursor in the temperature range of calcination (750–1000°C) leading to corrosion and formation of cracks in the saggar. The frequent failure of saggar causes a lot of waste, which could be reduced by choosing corrosion‐resistant materials. To understand the corrosion mechanism in the system MgO–Al2O3–SiO2, the materials MgO, Al2O3, MgAl2O4, and SiC (instead of SiO2) were embedded in premixed NMC precursor and calcined at T = 780°C for 50, 100, 150 and 200 h. The formed phases were determined by phase and microstructure analysis. Finally, the formation of LiAlO2 and Li5AlO4 is associated with a lower growth rate of the corrosion layer compared with Li4SiO4, while MgO is inert. The reactivity with NMC can be ordered as follows: SiO2 > Al2O3 > MgO. [ABSTRACT FROM AUTHOR]

Policy decisions shape strategies which in turn influence the outcome. The expected outcome of medical education in India is to produce an MBBS graduate of first contact. Are we able to do so or are we failing in that and what are the reasons behind our failure Is it a failure on part of the regulatory body to align with the expected outcome using a continuity of approach or a willingness to accept transitory as the process to achieve the objective? [ABSTRACT FROM AUTHOR]

Lithium Nickel Manganese Cobalt Oxides (NMC) are one of the most used cathode materials in lithium-ion batteries, and they will become more relevant in the following years due to their potential in electric vehicles. Unfortunately, this material experiences microcracking during the battery operation due to the volume variations, which is detrimental to the battery performance and limits the lifetime of the electrodes. Thus, understanding mechanical degradation is fundamental for the development of advanced batteries with improved capacity and limited degradation. In this work, we propose a chemo-mechanical model, including a stochastic phase-field fracture approach, to design structurally stable NMC electrodes. We include the degradation in the mechanical and chemical contributions. The heterogeneous NMC microstructure is considered by representing the material's tensile strength with a Weibull distribution function, which allows to represent complex and non-deterministic crack patterns.We use our model to provide a comprehensive analysis of mechanical degradation in NMC111 electrodes, including the effect of particle size, C-rate, and depth of charge and discharge. Then, we analyze the influence of the electrode composition (namely, Ni content) on the structural integrity. We use this information to provide design guides for functionally-graded electrodes with high capacity and limited degradation.

State‐of‐the‐art ternary layered oxide cathode active materials in Li‐ion batteries (LIBs) consist of polycrystalline (PC), i.e., micron‐sized secondary particles, which in turn consist of numerous nanosized primary particles. Recent approaches to develop single crystals (SCs), i.e., single and separated micron‐sized primary particles, appear promising in terms of cycle life given their mechanical stability. However, a direct and systematic (“fair”) comparison of SC with PC in LIB cell application remains a challenge due to both differences on material level and state‐of‐charge (SoC), as SCs typically have slightly lower delithiation capacities/Li+ extraction ratios. In this work, PC and SC Li[Ni0.8Mn0.1Co0.1]O2 (NMC811) are synthesized with comparable bulk and surface characteristics from identical self‐synthesized precursors. Indeed, the cycle life of SCs is not only superior, when conventionally charged to equal upper cutoff voltage (UCV), as shown in NMC||Li and NMC||graphite cells, but also after adjusting UCVs to similar SoCs, where bigger SCs counterintuitively have even a better rate performance and cycle life.

Policy decisions shape strategies which in turn influence the outcome. The expected outcome of medical education in India is to produce an MBBS graduate of first contact. Are we able to do so or are we failing in that and what are the reasons behind our failure Is it a failure on part of the regulatory body to align with the expected outcome using a continuity of approach or a willingness to accept transitory as the process to achieve the objective?

This paper examines the environmental impacts of Li-NMC batteries throughout their life cycle using life cycle assessment with OpenLCA software V1.11.0 and data from the Ecoinvent database and manufacturers. Results show that the most significant environmental impact occurs during battery mining and production phase (76.93 %), followed by battery use phase (17.13 %), and battery pyrometallurgical recycling (2.32 %). The battery mining and production phase is also the most energy-intensive (67.76 %), followed by battery pyrometallurgical recycling (23.27 %) and hydrometallurgical processes (8.023 %). The battery carbon footprint is calculated at 189.357 kg CO2-eq/kWh, with manufacturing and mining phases dominating energy consumption (67.76 %). The battery estimated cost payback period is approximately 5.7 years when the calculations were done using the banks' tariff and about 9 years when the hotel's tariff was applied, while for household usage, the cost payback period was estimated to be 17.5 years.

Battery electric vehicles (BEVs) are being considered as a replacement technology for diesel vehicles in underground mining of mineral resources. However, many issues related to BEVs in industrial applications still require more detailed research. One significant topic is the heat load—BEVs' heat emission into the working environment during regular operation. This paper provides an overview of the thermal behavior of NMC and LFP Li-ion cells tested under various conditions, which is an important step in determining the overall heat load of BEVs. The surface temperature of three NMC and one LFP 18650 Li-ion cells was monitored during charging and discharging at four different rates, at constant ambient temperatures of 30 °C and 40 °C. The main results pertain to the cell's thermal behavior during charging and discharging, highlighting the distinctive temperature profiles of NMC and LFP cells.

It is imperative that a sustainable approach to the recycling of lithium-ion batteries (LIBs)—in particular the spent NMC cathodes—which reach their end-of-life (EOL) is realized as 11 million metric tonnes are expected to reach EOL by 2030. The current recycling processes based on pyrometallurgy and hydrometallurgy are not fully sustainable options as they recover only the value metals. By contrast direct recycling that aims in regenerating EOL LIB cathodes without breaking down the active compound’s crystal structure offers the most sustainable option. In this paper the direct recycling of NMC cathodes is investigated in combination with their upcycling. Upcycling is going to be in growing demand since the first generation NMC 111 cathode chemistries evolve to higher energy/nickel-rich formulations. In this work, the baseline is established for direct recycling of low and high nickel NMC cathodes by analyzing the three key steps of chemical delithiation of pristine NMC cathode material, hydrothermal relithiation (4M LiOH for 4 h at 220 °C), and annealing (4 h at 850 °C) in order to set the ground for investigating the upcycling of NMC 111 to NMC 622. Upcycling is affected via the co-addition of pre-calculated excess NiSO4 and Li2CO3 salts during annealing, following the hydrothermal relithiation step. Use of NiSO4 that is commonly used as p-CAM provides a lower cost alternative to Ni(OH)2 as Ni source. Characterization revealed the upcycled material to have been endowed with the typical α-NaFeO2 layered structure and have surface morphology and composition similar to pristine NMC material. The upcycled NMC 622 cathode yielded good cycling stability (91.5% retention after 100 cycles) and >99% Coulombic efficiency albeit with certain polarization loss justifying further optimization studies.

This paper provides a comprehensive exploration of float current analysis in lithium-ion batteries, a promising new testing method to assess calendar aging. Float currents are defined as the steady-state trickle charge current after a transient part. In the literature, a correlation to capacity loss was reported. Assuming the float current compensates for the voltage decay over time and is linked to calendar aging, effects from voltage slippery must be considered. The dU/dQ analysis suggests solely a loss of active lithium. Therefore, we investigate the solid electrolyte interphase (SEI) growth as the general aging mechanism to explain the origin of float currents. Our results show that the voltage slippery theory holds true within the low to middle test voltage ranges. However, the theory's explanatory power begins to diminish at higher voltage ranges, suggesting the existence of additional, yet unidentified, factors influencing the float current. A shuttle reaction or lithiation of the cathode by electrolyte decomposition are the most promising alternative aging mechanisms at high voltages. The paper proposes a unique voltage slippery model to check for correlations between aging mechanisms, the float current test and the check-up test. For a better understanding, test strategies are proposed to verify/falsify the aging mechanisms beyond SEI. [ABSTRACT FROM AUTHOR]

Introduction : Early clinical exposure (ECE) is a new teaching method introduced in the first year of medical school to bridge the gap between pre-clinical and clinical subjects. The impact of ECE on learning anatomy has not been extensively studied. Objectives: To examine the perceptions of first-year medical undergraduates towards ECE in learning anatomy. Methods: 197 first-year MBBS students who attended 30 hours of ECE sessions were surveyed through a Google form with closed and open-ended questions. Categorical data was represented by frequency and percentage, and continuous variables by mean ± SD. Results: 94.6% of the respondents agreed that ECE was an interesting method of learning anatomy compared to traditional lectures, while 5.4% disagreed. 95.1% of students agreed that ECE motivated them to read more on the topics covered, while 4.9% felt ECE showed no impact on their motivation to study. Students strongly believed that ECE helped them understand the topics taught in Anatomy better (36.5%, n=72), retain information (35.5%, n=70), correlate with clinical scenarios (48.2%, n=95) 95.6% students opined that the frequency of ECE sessions should be increased and incorporated along with regular lectures in Anatomy. Conclusion: ECE sessions were well appreciated and accepted by students. ECE helps in understanding concepts in anatomy better, makes correlation with clinical aspects easier, and retaining information learned through ECE sessions is possible. ECE may serve as a great tool in imparting quality medical education.

Background: Foundation course is an integral part of MBBS course and curriculum introduced by the National Medical Commission (NMC) that is cogently grounded to bridge conceptual and contextual gap of medical education placed at beginning of curriculum. Objective: This feedback evaluation was conducted on the First year 2019 MBBS students as a part of the foundation course program promulgated by the NMC to get candid reflection. Methods: An unlinked anonymous self-administered pretested open-ended questionnaire on feedback of content and outcome was used on internalization of 169 First year MBBS students regarding the month-long foundation course. Qualitative responses were analyzed on ‘overall impression’ on the course; ‘best’, ‘worst’ and ‘unnecessary’ parts of the course; lastly open question on ‘How the Foundation course could have been better?. Results: Overall agreement on positive aspects was felt on schedule, facilitators, language of teaching, extracurricular activities. Best parts of the course were visits to the departments of College & Hospital including emergency and health centres, Basic Life Support, Immunization, History of Medicine, Taekwondo, Co-curricular physical activities, Communication, Interaction and Dedication of teachers, Cardiopulmonary resuscitation (CPR). Worst parts were Sports, Yoga, language class, strict 75% attendance. Unnecessary parts were Sports, Yoga, English compulsory class; Music, Computer. On ‘How the Course could have been better’ general comments was addition of subject specific classes and flexible attendance. Conclusions: This feedback analysis deduced acceptance and effectiveness of the course for undergraduate students to help them cope with stressful active professional learning later.

Background: Electives have been introduced under CBME for undergraduate Medical students. Objective: To identify the perceptions of faculty members in understanding the elective module of NMC. Methodology: A cross sectional study was done among the 60 ACME PARTICIPANTS of a nodal center for a period of one week. the data was collected using a predesigned, pre-tested questionnaire under the following areas -What measures can be taken to provide out of the institution experiences in electives and the anticipated difficulties in that process?? Who are the stakeholders involved in implementing electives and what are their roles and responsibilities at institute level: how elective students assessment can be done and what are the eligibility criteria for a preceptor under elective? Quantitative data was analysed and expressed in percentages and proportions, qualitative data was grouped under themes and subthemes Results: For providing the out of the institution experiences a total of 38 external institutions were enlisted by the participants, and they have opined that -apart from identifying external institutions and external preceptor, MOU has to be established with external institutions and elective module has to be developed in liaison with external preceptor. INSTITUTIONAL ELECTIVE COMMITTEE {IELCT} model proposed for the roles and responsibilities, a preceptor should be a regular faculty: Assistant professors with more than 2 years experience; who have undergone CISP, BCBR; with desired leadership and communication skills should be considered. Availability of experienced, motivated preceptors, students preference for easy/similar electives, safety of students during outside electives are the challenges identified. Conclusion: as preparation for electives is in the nascent stage in most of institutions we need to be more flexible in the initial few years and each stakeholder should put efforts as per their roles and responsibilities streamline and make electives as student-friendly as possible

Background: Community engagement in medical education gives the students an insight into the living conditions of the public and how they influence their health. Community Medicine department accomplish this through field practice and family health studies. The Family Adoption Programme (FAP), newly mandated for all medical undergraduate students, brings its own set of challenges and opportunities. Family Adoption Programme aims to provide an experiential learning opportunity to Indian medical graduates towards community-based health care and thereby equity in health Objectives: 1. To study the perceptions of Phase I MBBS Students on Family Adoption Program. 2. To determine the output of FAP implementation in MBBS curriculum. Methodology: A Cross-sectional study was conducted between August to November 2023 including 1st year MBBS students of MKCG Medical College, Berhampur, Odisha. A brief orientation was conducted by Dept. of Community Medicine on needs and competencies of FAP as recommended by the National Medical Commission(NMC). Students were sensitized to the FAP proforma prepared by the department. Periodic FAP visits for students in 4 groups was planned & conducted along with their assigned mentors at the selected nearby village. During these visits, students interacted with the families and details regarding health profile of the family were documented. Students perception & feedback was taken by Questionnaire using Google Form. A total 250 students were enrolled in FAP and 172 submitted their feedback. Data was analyzed using appropriate statistical tests and software. Results: The study included 172 1st year MBBS students with age range of 18-26 years & mean age of 20.58± 1.315 years. Among them, 66.9% were males & 33.1% were females.66.9% of students responded that FAP was a very good experience.55.2% of study participants were satisfied with their adopted family. Most of the students were interested to be a part of such activity throughout the professional years. Conclusion: Implementation of FAP requires meticulous planning, intersectoral co-ordination, good sensitization and training activities

The use of batteries in modern electronic devices and electric cars is becoming increasingly important. Batteries with high energy density, high rate and cycle capability, as well as operational safety, are in high demand today. The cathode of a lithium-ion battery is a part that significantly affects the performance of the battery. LiNiMnCoO2 (NMC) cathode, especially in the composition of LiNi0.8Mn0.1Co0.1O2 (NMC811), has high specific capacity but not high thermal and electrical conductivity stability. To improve the temperature stability and performance of the battery, conductive elements such as graphene can be added. The addition of graphene can increase battery performance due to its high electrical conductivity characteristics. In this study, the addition of graphene on NMC cathode through a simple solid-state technique along with direct mixing was shown to improve the cathode characteristics. The addition of graphene on the NMC cathode also proved to be capable of improving the cycle stability and rate capability. The retention capacity is 95.83 %, higher than that of the cathode without graphene modification, which is 92.27 % after 100 cycles with 1C current, and comparable to the capability of commercial batteries. The ability to work under rapid charge and discharge conditions was also well demonstrated with a capacity drop of 5.44 % over 200 cycles at a charge and discharge current of 5C. The addition of graphene was also shown to improve the safe use of NMC batteries. With the test at 5C current, the highest temperature of the battery was 46.52 °C, which is still considered safe for the operation of lithium ion-based batteries at high currents. In this research, the use of a simple solid-state method to mix the graphene with NMC811 cathode is proven to be able to produce lithium-ion batteries with superior performance. This offers ease in terms for use in large-scale production of cathode preparation that can produce high-performance cathodes.

The demand for lithium-ion batteries (LIBs) has skyrocketed due to the fast-growing global electric vehicle (EV) market. The Ni-rich cathode materials are considered the most relevant next-generation positive-electrode materials for LIBs as they offer low cost and high energy density materials. However, by increasing Ni content in the cathode materials, the materials suffer from poor cycle ability, rate capability and thermal stability. Therefore, this review article focuses on recent advances in the controlled synthesis of lithium nickel manganese cobalt oxide (NMC). This work highlights the advantages and challenges associated with each synthesis method that has been used to produce Ni-rich materials. The crystallography and morphology obtained are discussed, as the performance of LIBs is highly dependent on these properties. To address the drawbacks of Ni-rich cathode materials, certain modifications such as ion doping, and surface coating have been pursued. The correlation between the synthesized and modified NMC materials with their electrochemical performances is summarized. Several gaps, challenges and guidelines are elucidated here in order to provide insights for facilitating research in high-performance cathode for lithium-ion batteries. Factors that govern the formation of nickel-rich layered cathode such as pH, reaction and calcination temperatures have been outlined and discussed.

Background: National Medical Commission (NMC) in their recent notification included the Family Adoption Program (FAP) in the undergraduate medical curriculum to provide a learning opportunity towards community- based health care to Indian Medical Graduates. Notification documented that around 65.5 % of population resides in rural settings (as per 2020 statistics) whereas availability of health care facilities and services are skewed towards urban set ups. The student is expected to establish a rapport, understand their health and related factors, and help improve the healthcare of the family, by extensions, the community. FAP brings its challenges and opportunities. It is a very challenging task to implement programme by allotting families to each student and sustaining the follow up throughout the undergraduate period. Objective: 1. To assess the perception of students towards FAP. 2. To assess attitude of students towards FAP Methodology: Medical students who have completed their first year MBBS in RIMS, After obtaining informed oral consent, predesigned semi-structured questionnaire will be distributed to students who have completed their first year of MBBS Raichur will be included in the study. Students who are willing to participate in the study will be included in the study. Results: Will be presented in the conference. Conclusion: As this study aims to find the Perception of FAP for medical students, results of the study can be utilized to analyse the factors and take appropriate actions in the coming days.

Nickel, the main raw material for lithium-ion batteries (LIB), is currently the most in-demand metal. The rising need for nickel and current environmental concerns have underscored the importance of recycling waste metal to recover its value. Meanwhile, a significant secondary source with a high metal value is spent catalyst. In this context, the acid leaching method was used to recover nickel from spent catalyst. This study aimed to synthesize Lithium Nickel Manganese Cobalt Oxide 622 (NMC622) from spent catalyst. To determine the optimal method, a comparative analysis was conducted between solidstate and co-precipitation methods. Recycled spent nickel catalyst to be used for cathode material was examined by analytical methods, i.e., XRD, FTIR, SEM-EDX, and electrochemical performance testing. The XRD, FTIR, and SEM-EDX tests produced similar outcomes, consistent with previous reports. However, in the electrochemical test, the co-precipitation method showed a specific capacity two times higher than the solid-state method. The NMC622 from the co-precipitation method (NMC622-CP) yielded a specific discharge capacity of 132.82 mAh.g-1 at 0.1C, while the retention capacity was 70% for 50 cycles at 0.5C. [ABSTRACT FROM AUTHOR]

Lithium‐ion battery cathode materials suffer from bulk and interfacial degradation issues, which negatively affect their electrochemical performance. Oxide coatings can mitigate some of these problems and improve electrochemical performance. However, current coating strategies have low throughput, are expensive, and have limited applicability. In this article, we describe a low‐cost and scalable strategy for applying oxide coatings on cathode materials. We report synergistic effects of these oxide coatings on the performance of aqueously processed cathodes in cells. The SiO2 coating strategy developed herein improved mechanical, chemical, and electrochemical performance of aqueously processed Ni‐, Mn‐ and Co‐based cathodes. This strategy can be used on a variety of cathodes to improve the performance of aqueously processed Li‐ion cells. [ABSTRACT FROM AUTHOR]

The practice of ophthalmology has advanced exponentially due to technology. This has raised the bar of medical care from acceptable visual acuity to the highest precision in acuity. In such an era, it is the need of the hour to be aware of the medico-legal implications in ophthalmology to avert any lawsuits. Lawsuits can be due to breach of confidentiality, inadequate consent, negligence, unmet expectations in a procedure, etc. The majority of lawsuits are related to cataract and corneal surgeries, but the instances of lawsuits related to retinal conditions are on the rise, especially those related to screening of Retinopathy of prematurity resulting in huge sums of compensations. The awareness of regulations can guide the healthcare professionals in such instances. These include the knowledge of laws governing every step of practice and the rights of both healthcare professionals and patients. In addition, clear communication regarding the risks, benefits, and outcomes of the procedure, strict adherence to guidelines, and meticulous documentation are effective tools to avoid litigations. This review article aims to describe various regulations governing the practice of ophthalmology, implications in everyday practice, and steps to safeguard against lawsuits.

The preparation of Ni-rich cathode materials is challenging due to the Ni2+ion sensitivity to oxidation during synthesis. The synthesis conditions during the manufacture of Ni-rich materials such as LiNi0.8Mn0.1Co0.1O2 (NMC811) therefore require stringent control. The co-precipitation step, applied in the synthesis of the metal hydroxide precursor, determines the secondary particle assembly formation, where it is typically desirable to produce uniform, spherical, ∼10μm-diameter structures. A stirred tank reactor is often employed to maintain a constant temperature of 60 °C and a controlled pH of between 10.5 and 11.5 in an inert atmosphere to maintain a high Ni2+/Ni3+ion ratio. This promotes the formation of an NMC hydroxide precursor (NixMnyCoz(OH)2) which is typically milled with a lithium salt and calcined to form LiNixMnyCozO2 with a layered α-NaFeO2 crystalline structure. This review outlines some of the critical synthetic parameters for the formation of spherical secondary assemblies of metal hydroxide precursors for nickel-rich layered cathodes.

Self-discharge of lithium-ion cells leads to voltage decay over time. In this work, the self-discharge was measured at 30 °C for three cell types at various voltage levels for about 150 days in a constant voltage mode determining the current at a high precision (float current). All cells exhibit a transient part leading to a steady-state, which is no longer influenced by reversible effects. To study the effect of the check-ups on the steady-state float current, the cells, interrupted and not interrupted by check-ups, were compared. The results indicate that both the transient processes and steady-state currents are highly reproducible. In the first period of the float current, the polarization dominates the measured current, followed by the anode overhang effect dominating the process for a period of 5–30 days. After the decline of both processes, a mostly constant steady-state in the order of µA is observed. The check-up interruption generally shows no apparent effect on the reached steady-state and results only in an extended settling time. A model to simulate the transient process and steady-state of float currents was developed. The model shows a high accuracy in reproducing the results and identifying the time needed to reach the steady-state. [ABSTRACT FROM AUTHOR]

Li1.11(Ni0.4Mn0.4Co0.2)O2 powders were chemically delithiated by (NH4)2S2O8 oxidizer to obtain Lix(Ni0.4Mn0.4Co0.2)O2 powders. The thermal behavior of two delithiated specimens, Li0.76Ni0.41Mn0.42Co0.17O2.10 and Li0.48Ni0.38Mn0.46Co0.16O2.07, was studied compared to the pristine specimen. Phase transitions at elevated temperatures were investigated by simultaneous thermal analysis (STA) and the gas evolution accompanying the phase transitions was analyzed by mass spectroscopy and an oxygen detector. The enthalpy of two delithiated samples and a pristine specimen were measured by a high temperature drop solution calorimeter. Based on these results, the enthalpies of formation were calculated. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive exploration of float current analysis in lithium-ion batteries, a promising new testing method to assess calendar aging. Float currents are defined as the steady-state trickle charge current after a transient part. In the literature, a correlation to capacity loss was reported. Assuming the float current compensates for the voltage decay over time and is linked to calendar aging, effects from voltage slippery must be considered. The dU/dQ analysis suggests solely a loss of active lithium. Therefore, we investigate the solid electrolyte interphase (SEI) growth as the general aging mechanism to explain the origin of float currents. Our results show that the voltage slippery theory holds true within the low to middle test voltage ranges. However, the theory’s explanatory power begins to diminish at higher voltage ranges, suggesting the existence of additional, yet unidentified, factors influencing the float current. A shuttle reaction or lithiation of the cathode by electrolyte decomposition are the most promising alternative aging mechanisms at high voltages. The paper proposes a unique voltage slippery model to check for correlations between aging mechanisms, the float current test and the check-up test. For a better understanding, test strategies are proposed to verify/falsify the aging mechanisms beyond SEI.

A combinatorial library of twenty-three, phase pure, near-NMC111 (LiNi0·33Mn0·33Co0·33O2) compositions were synthesised and their electrochemical performance, was mapped (in lithium ion half-cells). Each of the 23 compositions was made in series, using a two-step process of 1) a rapid initial continuous hydrothermal precipitation, followed by 2) solid state lithiation. The 23 lithiated NMC samples were then subjected to analytical methods including electron microscopy (selected samples), Powder X-ray Diffraction and electrochemical tests in half cell Li-ion configurations versus Li metal. A sample with a Ni:Mn:Co (NMC) ratio of 39:28:33, revealed a specific capacity of 150 mA h g−1 at a C/20 rate, which was 63 and 43% greater capacity than NMC111 and NMC433 samples produced in this work, respectively. The sample with NMC ratio 47:25:28, showed the best capacity retention characteristics, retaining 70% of its C/20 capacity at 1C, after 40 cycles. Further analysis of all the samples by cyclic voltammetry and electrochemical impedance spectroscopy, allowed compositional mapping of diffusion coefficients. Overall, the mapping data revealed a gradual change of properties across compositional space, which has validated our combinatorial approach and allowed identification of the optimum performing near-NMC111 cathode materials.

The present study models the role of electrode structural characteristics on the thermal beha­viour of lithium-ion batteries. Preliminary modelling runs have employed a 1D lithium-ion battery, coupled to a two-dimensional axisymmetric model using silicon as the battery anode material. The two models are coupled by the heat generated and the average temperature. Our study is focused on the silicon anode particle sizes, and it is observed that silicon anodes with nano sized particles reduced the heating of the battery under charge/discharge cycles when compared to anodes with larger particles. These results are discussed in context of the relationship between particle size and thermal transport properties in the electrode.

The potential of electrodialysis to recycle spent lithium-ion batteries was assessed by investigating the recovery of lithium(I) from a synthetic solution representative of the aqueous effluent generated by shredding spent lithium-ion batteries underwater. Likewise, electrodialysis was tested for the selective recovery of lithium(I) towards cobalt(II), nickel(II) and manganese(II) from a synthetic solution representative of the leaching liquor of cathode materials. NMR spectroscopy showed that the implementation of electrodialysis to extract lithium from the aqueous effluent produced during battery shredding underwater should take into account the presence of HF generated by PF6− hydrolysis. In particular, it seems relevant to perform shredding under calcium chloride solution in order to precipitate fluoride and reduce HF generation. This work also showed that electrodialysis is an interesting technology for selectively recovering lithium from the leach solution of spent cathode materials, providing that divalent cations were previously removed to avoid metal precipitation inside the electrodialysis membranes. After removing cobalt(II) and nickel(II) at pH 2.8 and manganese(II) partially at pH 5.5 by using the ion exchange resin Dowex M4195, it is possible to extract and selectively concentrate lithium by electrodialysis without coextracting manganese(II) by using a lithium-selective membrane (faradic efficiency of 57.6%, permselectivity for lithium towards manganese of 6.9). Finally, a hybrid flowsheet implementing mineral processing and hydrometallurgy, including electrodialysis, ion exchange and crystallization stages, was proposed based on these results to reduce effluent generation and produce metal salts from spent lithium-ion battery. [ABSTRACT FROM AUTHOR]

Simulation is a technique where the situation or a process is imitated. This process makes one to pretend the scenario. Aviation industry is one of the oldest industry which uses simulation technique to simulate the aviation technique. The main aim of having simulation lab is to make students acquire psychomotor skills before they actually treat the patients. Presently the National Medical Council of India has made it mandatory to have a skill lab but desirable to have a simulated mannequin for the training of medical students before actually treating the patients. Various advantages and disadvantages are appreciated in simulation technique. It is not very far that Dental council of India may make compulsory training of certain simulated modules in dentistry before treating the patient. Simulation lab in the pandemic like COVID has really helped people to undergo extensive training before treating patients, especially one who were catering the COVID ward or intensive care units. The simulation in dentistry is not a very old technique, certain technique are already in practice, but this article tries to highlight the necessity and gray areas where simulation can be improved for the benefit of students to learn and for the benefit of patients in view of safety. [ABSTRACT FROM AUTHOR]

Silicon has become an integral negative electrode component for lithium-ion batteries in numerous applications including electric vehicles and renewable energy sources. However, its high capacity and low cycling stability represent a significant trade-off that limits its widespread implementation in high fractions in the negative electrode. Herein, we assembled high-capacity (1.8 Ah) cells using a nanoparticulate silicon–graphite (1:7.1) blend as the negative electrode material and a LiFePO4–LiNi0.5Mn0.3Co0.2O2 (1:1) blend as the positive electrode. Two types of cells were constructed: cylindrical 18650 and pouch cells. These cells were subjected both to calendar and cycling aging, the latter exploring different working voltage windows (2.5–3.6 V, 3.6–4.5 V, and 2.5–4.5 V). In addition, one cell was opened and characterised at its end of life by means of X-ray diffraction, scanning electron microscopy, and further electrochemical tests of the aged electrodes. Si degradation was identified as the primary cause of capacity fade of the cells. This work highlights the need to develop novel strategies to mitigate the issues associated with the excessive volumetric changes of Si. [ABSTRACT FROM AUTHOR]

Electrochemical energy storage plays a vital role in combating global climate change. Nowadays lithium-ion battery technology remains the most prominent technology for rechargeable batteries. A key performance-limiting factor of lithium-ion batteries is the active material of the positive electrode (cathode). Lithium- and manganese-rich nickel manganese cobalt oxide (LMR-NMC) cathode materials for Li-ion batteries are extensively investigated due to their high specific discharge capacities (>280 mAh/g). However, these materials are prone to severe capacity and voltage fade, which deteriorates the electrochemical performance. Capacity and voltage fade are strongly correlated with the particle morphology and nano- and microstructure of LMR-NMCs. By selecting an adequate synthesis strategy, the particle morphology and structure can be controlled, as such steering the electrochemical properties. In this manuscript we comparatively assessed the morphology and nanostructure of LMR-NMC (Li1.2Ni0.13Mn0.54Co0.13O2) prepared via an environmentally friendly aqueous solution-gel and co-precipitation route, respectively. The solution-gel (SG) synthesized material shows a Ni-enriched spinel-type surface layer at the {200} facets, which, based on our post-mortem high-angle annual dark-field scanning transmission electron microscopy and selected-area electron diffraction analysis, could partly explain the retarded voltage fade compared to the co-precipitation (CP) synthesized material. In addition, deviations in voltage fade and capacity fade (the latter being larger for the SG material) could also be correlated with the different particle morphology obtained for both materials. [ABSTRACT FROM AUTHOR]

Spent nickel catalyst will be harmful to the environment if it is not processed or used properly. In fact, this waste still has a high nickel content. The treatment of spent nickel catalysts has been widely reported, but limited to nickel extraction. Since the lithium-ion batteries demand is continued to increase, then nickel is the most sought-after metal. Consequently, nickel from spent nickel catalysts could be developed as secondary source for lithium-ion battery cathode. This study aims to utilize spent nickel catalysts into more valuable materials. Nickel that has been extracted and mixed with Mn and Co has been used as raw material for nickel-rich cathode, namely NMC. Nickel extraction and NMC synthesis were using the acid leaching method followed by co-precipitation[WI1] [SSN2] . Based on the functional test performed in this work, nickel from spent nickel catalyst can be applied to Li-ion batteries. The sintering temperature that gives good characteristics and electrochemistry was found 820oC. The galvanostatic charge-discharge test gave specific capacity results for NMC of 110.4 mAh/g. The cycle test showed that NMC synthesized from spent nickel catalyst can be carried out up to 50 cycles with a capacity retention of 87.18%.

The expansion of technology motivates the increase of global demands for critical minerals. In this context, the exploration of secondary sources of these components is expanding. End-of-life batteries can be seen as potential sources of lithium, cobalt, nickel and manganese for electric vehicles or diverse applications in electronic equipments. This paper provides a comprehensive evaluation of the recovery of metals from waste batteries with diverse chemistry composition. Lithium cobalt oxide (LCO) and lithium nickel cobalt manganese oxide (NMC) batteries were co-treated with polyvinyl chloride (PVC) channels under supercritical water, varying reaction temperature (400–600 °C) and PVC/Battery composition (0–3 m/m) in a tubular continuous reactor. Results show high recovery rates for all metals, with up to 90% percentage recovery of lithium and cobalt in all cases. Temperature and feed composition were identified as determining factors for the recovery of lithium from LCO batteries. In the case of cobalt, temperature was identified as the most important factor that affects its recovery. The selected optimal conditions for cobalt recovery in the solid products of reactions were identified for batteries LCO and NMC: temperature of 600 °C and PVC/Battery ratio of 3.0 and temperature of 500 °C and PVC/Battery ratio of 1.5, respectively. Environmental impacts, primarily Global Warming Potential (GWP), were minimal, with 4.71·10−5 kg CO 2 eq., indicating the benefits of the process as an eco-efficient and promising route for the recycling of valuable metals. [Display omitted] • Cobalt and nickel recovery of 97.08% and 62.37% in solid products from NMC batteries. • 94.20 %mol of H 2 produced at the optimal conditions of LCO battery treatment. • Low environmental impact of the proposed process, with a GWP of 4.71·10⁻⁵. • Cobalt and nickel chlorides identified in liquid products from LCO and NMC batteries. [ABSTRACT FROM AUTHOR]

One of the weaknesses of the LiPF 6 -based electrolyte is its poor thermal stability. It can result in an accelerated battery capacity fading and CO 2 gas generation due to the formation of PF 5 which are highly reactive towards the electrolyte solvents. As the formation of PF 5 is inevitable, efforts are dedicated to inhibiting its deleterious impact by adding a Lewis base to form a complex. However, no study investigates the PF 5 -complexation efficiency through gas analysis. Here, gas analysis shows that N-containing additives are effective in reducing gas generation upon electrolyte storage at 55 °C. Out of our expectations, the trend is reversed when it comes to thermal storage of NMC-graphite batteries, involving competitive chemisorption processes on the NMC acid and basic sites. It turned out that, NMC surface can be more effective than additives in mitigating the thermal degradation of the electrolyte. Furthermore, the gas level thermally generated does not decrease while replacing the culprit LiPF 6 salt by mixtures of LiFSI + LiPF 6 or LiFSI + LiODFB. Especially in presence of LiODFB, water triggers hydrolysis reactions that also lead to gas evolution. [Display omitted] • CO 2 gas analysis as a very sensitive tool to study electrolyte thermal degradation. • N-containing additives are effective for PF 5 -complexing in electrolyte alone. • PF 5 adsorbs onto the NMC surface, preventing electrolyte solvents degradation. • LiFSI hydrolysis leads to LiODFB decomposition, generating gas. [ABSTRACT FROM AUTHOR]

Li1.11(Ni0.4Mn0.4Co0.2)O2 powders were chemically delithiated by (NH4)2S2O8 oxidizer to obtain Lix(Ni0.4Mn0.4Co0.2)O2 powders. The thermal behavior of two delithiated specimens, Li0.76Ni0.41Mn0.42Co0.17O2.10 and Li0.48Ni0.38Mn0.46Co0.16O2.07, was studied compared to the pristine specimen. Phase transitions at elevated temperatures were investigated by simultaneous thermal analysis (STA) and the gas evolution accompanying the phase transitions was analyzed by mass spectroscopy and an oxygen detector. The enthalpy of two delithiated samples and a pristine specimen were measured by a high temperature drop solution calorimeter. Based on these results, the enthalpies of formation were calculated.

Self-discharge of lithium-ion cells leads to voltage decay over time. In this work, the self-discharge was measured at 30 ∘C for three cell types at various voltage levels for about 150 days in a constant voltage mode determining the current at a high precision (float current). All cells exhibit a transient part leading to a steady-state, which is no longer influenced by reversible effects. To study the effect of the check-ups on the steady-state float current, the cells, interrupted and not interrupted by check-ups, were compared. The results indicate that both the transient processes and steady-state currents are highly reproducible. In the first period of the float current, the polarization dominates the measured current, followed by the anode overhang effect dominating the process for a period of 5–30 days. After the decline of both processes, a mostly constant steady-state in the order of μA is observed. The check-up interruption generally shows no apparent effect on the reached steady-state and results only in an extended settling time. A model to simulate the transient process and steady-state of float currents was developed. The model shows a high accuracy in reproducing the results and identifying the time needed to reach the steady-state.

We report an environmentally benign recycling approach for large-capacity nickel manganese cobalt (NMC) batteries through the electrochemical concentration of lithium on the anode and subsequent recovery with only water. Cycling of the NMC pouch cells indicated the potential for maximum lithium recovery at a 5C charging rate. The anodes extracted from discharged and disassembled cells were submerged in deionized water, resulting in lithium dissolution and graphite recovery from the copper foils. A maximum of 13 mg of lithium salts per 100 mg of the anode, copper current collector, and separator was obtained from NMC pouch cell cycled at a 4C charging rate. The lithium salts extracted from batteries cycled at low C-rates were richer in lithium carbonate, while the salts from batteries cycled at high C-rates were richer in lithium oxides and peroxides, as determined by X-Ray photoelectron spectroscopy. The present method can be successfully used to recover all the pouch cell components: lithium, graphite, copper, and aluminum current collectors, separator, and the cathode active material. • Lithium recovery by electrochemical concentration in 250 mA H NMC batteries. • Li selectively recovered from anode surface using only water, at room temperature. • Cathode material, current collectors, graphite, and separator are also recovered. • Recovered Li product depends on charging rates during electrochemical concentration. [ABSTRACT FROM AUTHOR]

To reduce the cobalt (Co) content in lithium-ion batteries, Ni-rich (high-Ni) lithium nickel manganese cobalt oxides (NMC) are pursued as one of the next-generation cathode materials. However, there is still debate on the crystal and electronic structures of the baseline, LiNiO 2. Density Functional Theory (DFT) calculations were performed to provide a theoretical understanding of Ni-rich NMC. First, it was found that the commonly used R 3 ¯ m structure for LiNiO 2 is metallic, contrary to the experimentally reported mix-conducting behavior. Among the four different space groups, R 3 ¯ m , C2/m , P2 1 /c , and P2/c , P2/c with charge disproportionation of Ni2+ and Ni4+ is the most energetically stable and semiconducting structure of LiNiO 2. Therefore, the atomic structures of representative Ni-rich NMC were built by partially replacing Ni with Co or Mn in the P2/c LiNiO 2 to form Li x Ni y Mn z Co 1-y-z O 2. In the fully lithiated (x = 1.0) high Ni content NMC (y > 0.5), the oxidation state of all Mn ions becomes 4+, while Co ions still maintain 3+, and part of the Ni ions become 2+ to compensate for the charge. Upon delithiation, the local environment shows more variation of the charge states on the transition metal (TM) ions. The average oxidation on each TM follows a sequence of losing electrons that starts from Ni2+ to Ni3+, then oxidizing Ni3+ and Co3+, while Mn4+ remains electrochemically inactive till x = 0. A general relationship for the oxidation state change in each TM as a function of x and y is derived and shows agreement with both modeling and experimental data. • The commonly used R 3 ¯ m symmetry (for LiCoO 2) is not the correct for LiNiO 2. • Built representative structures for Ni-rich Li x Ni y Mn z Co 1-y-z O 2 cathode materials. • Revealed the structure and redox mechanisms for Li x Ni y Mn z Co 1-y-z O 2. • Derived a general relationship for oxidation state change as a function of SOC. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries have been commonly employed as power sources in portable devices and are of great interest for large-scale energy storage. To further enhance the fundamental understanding of the electrode structure, we report on the use of multi-wavelength Raman spectroscopy for the detailed characterization of layered cathode materials for Li-ion batteries (LiCoO2, LiNixCo1−xO2, LiNi1/3Mn1/3Co1/3O2). Varying the laser excitation from the UV to the visible (257, 385, 515, 633 nm) reveals wavelength-dependent changes in the vibrational profile and overtone/combination bands, originating from resonance effects in LiCoO2. In mixed oxides, the influence of resonance effects on the vibrational profile is preserved but mitigated by the presence of Ni and/or Mn, highlighting the influence of resonance Raman spectroscopy on electronic structure changes. The use of UV laser excitation (257, 385 nm) is shown to lead to a higher scattering efficiency towards Ni in LiNi1/3Mn1/3Co1/3O2 compared to visible wavelengths, while deep UV excitation at 257 nm allows for the sensitive detection of surface species and/or precursor species reminiscent of the synthesis. Our results demonstrate the potential of multi-wavelength Raman spectroscopy for the detailed characterization of cathode materials for lithium-ion batteries, including phase/impurity identification and quantification, as well as electronic structure analysis. [ABSTRACT FROM AUTHOR]

Electrical models of battery cells are used in simulations to represent batteries' behavior in various fields of research and development involving battery cells and systems. Electrical equivalent circuit models, either linear or nonlinear, are commonly used for this purpose and are presented in this article. Various commercially available cylindrical, state-of-the-art lithium-ion battery cells, both protected and unprotected, are considered. Their impedance properties, according to four different equivalent circuit models, are measured using electrochemical impedance spectroscopies. Furthermore, the pricing, impedance, specific energy, and C-rate of the chosen battery cells are compared. For example, it is shown that the energy density of modern 18650 cells can vary from a typical value of 200 to about 260 Wh kg−1, whereas the cell price can deviate by a factor of about 3 to 5. Therefore, as a result, this study presents a concise but comprehensive battery parameter library that should aid battery system designers or power electronic engineers in conducting battery simulations and in selecting appropriate battery cells based on application-specific requirements. In addition, the accuracies and computational efforts of the four equivalent circuit models are compared. [ABSTRACT FROM AUTHOR]