Search Results (62)

This paper presents a case study of research-based learning (RBL) implemented in an undergraduate engineering course through a module titled “State-of-Charge Monitoring of Li-Ion Batteries Using Thermographic Surface-Temperature Measurements”. The experiment involved 10 third-year engineering students and employed a single-group pre- and post-test design and a lecturer interview. The module provided students with an authentic research experience using advanced laboratory equipment. The study examines students’ attitudes, satisfaction, and development of research skills, as well as the lecturer’s perspective on the advantages and challenges of RBL. While the study had a limited timeframe and specific design characteristics, the findings could benefit researchers interested in integrating RBL. Results indicated that students showed initial interest, primarily seeking practical knowledge and skills. By the end of the experiment, they reported that RBL fostered high motivation and strengthened their sense of commitment, responsibility, and initiative. Despite the students’ enthusiasm and the lecturer’s motivation, the results show that preparing and implementing RBL required significant time and effort on the lecturer’s part. The students’ lack of prior knowledge in research activities and the limited time frame posed considerable challenges. Recommendations include implementing RBL over a longer period and involving additional educators to enhance student support. Full article

Accurate estimation of the open-circuit voltage (OCV) as a function of state of charge (SOC) is critical for reliable battery-management system (BMS) design in lithium-ion battery applications. However, at low temperatures, polarization effects distort the measured OCV–SOC profile due to premature voltage cutoffs during low-rate testing. This paper presents an offsetting-based correction method that reconstructs the truncated portions of the OCV curve by extrapolating the charge/discharge data beyond the cutoff points using simple voltage offsets. The approach is applied entirely in post-processing, requiring no modification to standard test protocols. Experimental validation using Samsung EB575152 Li-ion cells across a wide temperature range (−25 °C to 50 °C) demonstrates that the method restores the full OCV span, reduces apparent capacity loss, and improves consistency across cells and temperatures. The proposed technique offers a practical and effective enhancement to standard OCV testing procedures for temperature-aware SOC modeling. Full article

Ionic liquid (IL)-based electrolytes have garnered significant interest for enhancing lithium-ion battery (LIB) safety due to their non-flammability, thermal stability, high conductivity, and broad electrochemical stability. We propose novel pyrrolinium-based ionic liquids to enhance lithium-ion mobility and address safety concerns in LIBs. This study investigated LiTFSI in [Pyr13] [FSI] ionic liquid for Li-ion batteries. The cyclic stability and rate performance of single-layer full cells with commercial graphite anode and NMC532 cathode were examined for the electrolyte required per cell and compared to those using a carbonate electrolyte (LP30). Electrolytes containing LiTFSI/[Pyr13] [FSI] exhibited satisfactory rate performance and stable cycling for 100 cycles. The reversible capacity was maintained at over 22 mAh for a cycle period of 100 cycles with an electrolyte loading of 161.8 µL/cm². These electrolytes exhibited the highest oxidation stability, surpassing 5.3 V compared to that of the Li⁺/Li reference electrode. Long cycle life of up to 1000 cycles was conducted, showing 80% capacity retention. Post-mortem analysis using scanning electron microscopy (SEM) and micro-Raman spectroscopy allowed observation of LiTFSI/ [Pyr13] [FSI] effects on cathode and anode active particle stability, and reduced formation of secondary reactions between the IL and battery electrodes. Full article

Metal anodes promise improvements in energy density and cost; however, their performance is determined within the first several nanometers at the interface. This review reports on how polymer-based artificial solid electrolyte interphases (SEIs) are engineered to stabilize Li and aqueous-Zn anodes, and how these designs are now evaluated against operando readouts rather than post-mortem snapshots. We group the related molecular strategies into three classes: (i) side-chain/ionomer chemistry (salt-philic, fluorinated, zwitterionic) to increase cation selectivity and manage local solvation; (ii) dynamic or covalently cross-linked networks to absorb microcracks and maintain coverage during plating/stripping; and (iii) polymer–ceramic hybrids that balance modulus, wetting, and ionic transport characteristics. We then benchmark these choices against metal-specific constraints—high reductive potential and inactive Li accumulation for Li, and pH, water activity, corrosion, and hydrogen evolution reaction (HER) for Zn—showing why a universal preparation method is unlikely. A central element is a system of design parameters and operando metrics that links material parameters to readouts collected under bias, including the nucleation overpotential (η_nuc), interfacial impedance (charge transfer resistance (R_ct)/SEI resistance (R_SEI)), morphology/roughness statistics from liquid-cell or cryogenic electron microscopy (Cryo-EM), stack swelling, and (for Li) inactive-Li inventory. By contrast, planar plating/stripping and HER suppression are primary success metrics for Zn. Finally, we outline parameters affecting these systems, including the use of lean electrolytes, the N/P ratio, high areal capacity/current density, and pouch-cell pressure uniformity, and discuss closed-loop workflows that couple molecular design with multimodal operando diagnostics. In this view, polymer artificial SEIs evolve from curated “recipes” into predictive, transferable interfaces, paving a path from coin-cell to prototype-level Li- and Zn-metal batteries. Full article

Fiber-based and fabric batteries signify a groundbreaking development in energy storage, allowing for the straightforward incorporation of power sources into wearable fabrics, intelligent apparel, and adaptable electronics. In this study, we introduce a novel strategy for one-step fabrication of a flexible lithium titanate oxide (Li₄Ti₅O₁₂, LTO) anode directly on a copper current collector via electrospinning, eliminating the need for high-temperature post-processing. Based on our previous work with electrospun nanofiber cathodes and carbon-based current collector, we prepared the LTO electrode using polyethylene oxide (PEO) as a binder and carbon additives to enhance mechanical integrity and conductivity. LTO fiber mats detached from the current collector were found to endure multiple instances of bending, twisting, and folding without any structural damage. LTO/Li cells incorporating electrospun fiber LTO electrodes with 72 wt% active material loading deliver a high capacity of 170 mAh g⁻¹ at 0.05 C. In addition, they demonstrate excellent cycling stability with a capacity loss of only 0.01% per cycle over 200 cycles and maintain a capacity of 160 mAh g⁻¹ at 0.1 C. The scalability of the heat-treatment-free method for fabricating flexible LTO anodes, together with the improved mechanical durability and electrochemical performance, offers a promising route toward the development of next-generation flexible and wearable energy storage devices. Full article

Wearable devices (WDs) are increasingly integrated into clinical workflows to enable continuous, non-invasive vital signs monitoring. Combined with Artificial Intelligence (AI), these systems can shift clinical monitoring from being reactive to predictive, allowing for earlier detection of deterioration and more personalized interventions. The value of these technologies lies not in absolute measurements, but in detecting physiological parameters trends relative to each patient’s baseline. Such a trend-based approach enables real-time prediction of deterioration, enhancing patient safety and continuity of care. However, despite their shared multiparametric capabilities, WDs are not interchangeable. This narrative review analyzes nine clinically validated devices, Radius VSM^® (Masimo Corporation, Irvine, CA, USA), BioButton^® (BioIntelliSense Inc., Redwood City, CA, USA. Distributed by Medtronic), Portrait Mobile^® (GE HealthCare, Chicago, IL, USA), VitalPatch^® (VitalConnect Inc., San Jose, CA, USA), CardioWatch 287-2^® (Corsano Health B.V., The Hague, The Netherlands. Distributed by Medtronic), Cosinuss C-Med Alpha^® (Cosinuss Gmb, Munich, Germany), SensiumVitals^® (Sensium Healthcare Limited, Abingdon, Oxfordshire, UK), Isansys Lifetouch^® (Isansys Lifecare Ltd., Abingdon, Oxfordshire, UK), and CheckPoint Cardio^® (CheckPoint R&D LTD., Kazanlak, Bulgaria), highlighting how differences in sensor configurations, battery life, connectivity, and validation contexts influence their suitability across various clinical environments. Rather than establishing a hierarchy of technical superiority, this review emphasizes the importance of context-driven selection, considering care setting, patient profile, infrastructure requirements, and interoperability. Each device demonstrates strengths and limitations depending on patient population and operational demands, ranging from perioperative, post-operative, emergency, or post-Intensive Care Unit (ICU) settings. The findings support a tailored approach to WD implementation, where matching device capabilities to clinical needs is key to maximizing utility, safety, and efficiency. Full article

The growing demand for high-energy, safe, and sustainable lithium-ion batteries has increased interest in nickel-rich cathode materials and solid-state electrolytes. This study presents a scalable wet-processing method for fabricating composite cathodes for all-solid-state batteries. The cathodes studied herein are high-nickel LiNi_0.90Mn_0.05Co_0.05O₂, NMC955, the sulfide-based electrolyte Li₆PS₅Cl, and alternative binders—polyvinyl alcohol (PVA) and polyisobutylene (PIB)—dispersed in toluene, a non-polar solvent compatible with the electrolyte. After fabrication, the cathodes were characterized using SEM/EDX, sheet resistance, and Hall effect measurements. Electrochemical tests were additionally performed in all-solid-state battery half-cells comprising the synthesized cathodes, lithium metal anodes, and Li₆PS₅Cl as the separator and electrolyte. The results show that both PIB and PVA formulations yielded conductive cathodes with stable microstructures and uniform particle distribution. Electrochemical characterization exposed that the PVA-based cathode outperformed the PIB-based counterpart, achieving the theoretical capacity of 192 mAh·g⁻¹ even at 1C, whereas the PIB cathode reached a maximum capacity of 145 mAh.g⁻¹ at C/40. Post-mortem analysis confirmed the structural integrity of the cathodes. These findings demonstrate the viability of NMC955 as a high-capacity cathode material compatible with solid-state systems. Full article

Research on the safety and impact of lithium-ion battery failure has focused on individual cells as lithium-ion batteries began to be used in small devices. However, large and complex battery packs need to be considered, and how the failure of a single cell can affect the system needs to be analyzed. This initial failure at the level of a single cell can lead to thermal runaway of other cells within the pack, resulting in increased risk. This article focuses on tests of mechanical abuse (perforation of cylindrical cells), overcharge (pouch cells), and heating (cylindrical cells with different arrangements and types of connection) to analyse how various parameters influence the mechanism of thermal runaway (TR) propagation. Parameters such as SoC (State of Charge), environment, arrangement, and type of connection are thoroughly evaluated. The tests also analyse the final state of the post-mortem cells and measure the internal resistance of the cells before and after testing. The novelty of this study lies in its analysis of the behavior of different types of cells at room temperature, since the behavior of lithium-ion batteries under adverse circumstances has been extensively studied and is well understood, failures can also occur under normal operating conditions. This study concludes that temperature is a crucial parameter, as overheating of the battery can cause an exothermic reaction and destroy the battery completely. Also, overcharging the cell can compromise its internal structure, which underlines the importance of a well-functioning battery management system (BMS). Full article

This study investigates the properties of LiCoO₂ coatings as cathodes for lithium-ion batteries, focusing on the effects of annealing on their structural, morphological, chemical, vibrational, and electrochemical characteristics. The LiCoO₂ coatings were deposited on silicon and glass substrates using RF magnetron sputtering at 100 W and subsequently annealed at 600 °C for 1 h. The films were characterized before and after annealing using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and electrochemical impedance spectroscopy (EIS). Annealing improved the crystallinity of LiCoO₂, which is critical for enhancing lithium-ion diffusion. Furthermore, an XPS analysis revealed a layered structure with a Li-rich outer layer and a Co-rich underlayer, indicating a more uniform distribution of Li and Co, along with increased oxygen content. Additionally, the annealing process refined the microstructure of the LiCoO₂ coating, positively impacting its electrochemical performance. A comparative analysis of cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) results demonstrated a significant improvement in the charge/discharge capacity post-annealing. This study successfully highlights the beneficial effects of annealing on LiCoO₂ thin-film cathodes, offering valuable insights for developing more efficient and sustainable lithium-ion batteries through sputter-deposition processes. Full article

A prototype of a mobile electric charging station was developed to simulate the energy supply to a rural medical post. A 20 m² medical post module was built, divided into two rooms (medical staff room and patient room) and a heater, a freezer, a refrigerator, lights and a personal computer were added inside. The mobile electric charging station was made up of an array of 2.88 kW flexible photovoltaic panels, a 48 V and 19.2 kW·h LiFePO₄ battery bank, a charger inverter with a total capacity of 5 kW and a 4 kW electric generator. All of this equipment was placed in an all-terrain pickup truck. Temperature sensors and electrical sensors were installed to evaluate the performance of the prototype in charging and discharging scenarios. Results were obtained according to the operation over 10 months in the city of Arequipa, Peru. The results indicate an indefinite autonomy on clear days, the autonomy varying between 7 and 10 days for a climate with medium cloudiness, and with very cloudy conditions (i.e., with rain), the autonomy is 2 to 3 days. In circumstances of low solar irradiance, the generator had to supply the energy, thereby improving energy autonomy. Full article

Li-CO₂ batteries (LCBs) have emerged as promising solutions for energy storage, with the added benefit of contributing to carbon neutrality by capturing and utilizing CO₂ during operation. In this study, a high-performance LCB was developed using a Ge-doped LiAlGeTi (PO₄)₃ (LAGTP) solid electrolyte, which was synthesized via a solution-based method by doping Ge into NASICON-type LATP. The ionic conductivity of the LAGTP pellets was measured as 1.04 × 10⁻³ S/cm at 25 °C. The LCB utilizing LAGTP and an MWCNT/Ru cathode maintained a stable cycling performance over 200 cycles at a current density of 100 mA/g, with a cut-off capacity of 500 mAh/g. Post-cycle analysis confirmed the reversible electrochemical reactions at the cathode. The integration of LAGTP as a solid electrolyte effectively enhanced the ionic conductivity and improved the cycle life and performance of the LCB. This study highlights the potential of Ge-doped NASICON-type solid electrolytes for advanced energy-storage technologies and offers a pathway for developing sustainable and high-performance LCBs. Full article

LiFePO₄ is a cathode material for lithium (Li)-ion batteries known for its excellent performance. However, compared with layered oxides and other ternary Li-ion battery materials, LiFePO₄ cathode material exhibits low electronic conductivity due to its structural limitations. This limitation significantly impacts the charge/discharge rates and practical applications of LiFePO₄. This paper reviews recent advancements in strategies aimed at enhancing the electronic conductivity of LiFePO₄. Efficient strategies with a sound theoretical basis, such as in-situ carbon coating, the establishment of multi-dimensional conductive networks, and ion doping, are discussed. Theoretical frameworks underlying the conductivity enhancement post-modification are summarized and analyzed. Finally, future development trends and research directions in carbon coating and doping are anticipated. Full article

We developed a basic lightweight powered wheelchair model using a participatory action design (PAD). We conducted two types of research to identify users’ desires and satisfaction with wheelchairs: one focused on identifying the problems and needs of manual or powered wheelchair users through focus group interviews (FGIs), and the other focused on capturing users’ post-experience feedback with the developed prototypes through usability testing (UT). We structured scenario-based usability tests and questionnaires to capture the participants’ experiences and needs, with the results indicating that both manual and powered wheelchair users emphasized the product’s lightness, design, cost, and battery and motor performance. This user-focused development resulted in higher satisfaction and usability. The significance of this study lies in the active involvement of wheelchair users throughout the research process, incorporating the obstacles and terrains they encounter in real community environments into the development. Future research should assess the usability of the final lightweight powered wheelchair, aiming to improve its affordability to wheelchair users through public benefits. Full article

LiFePO₄ (LFP) batteries are well known for their long cycle life. However, there are many reports of significant capacity degradation in LFP battery packs after only three to five years of operation. This study assesses the second-life potential of commercial LFP batteries retired from electric vehicles (EVs) by evaluating their aging characteristics at the cell and module levels. Four LFP cells and four modules were subjected to aging tests under various conditions. The results indicate that LFP cells exhibit long life cycles with gradual capacity degradation and a minimal internal resistance increase. Module-level analysis reveals significant balance issues impacting capacity recovery. Incremental capacity analysis (ICA) and post-mortem analysis identify the loss of active materials and lithium inventory as key aging mechanisms. This study provides the optimal working conditions of second-life LFP batteries and suggests that, with proper balancing systems, LFP batteries can achieve extended second-life use in stationary energy storage applications, emphasizing the importance of effective balance management for sustainable battery utilization. Full article

Lithium iron phosphate (LiFePO₄ or LFP) is a promising cathode material for lithium-ion batteries (LIBs), but side reactions between the electrolyte and the LFP electrode can degrade battery performance. This study introduces an innovative coating strategy, using atomic layer deposition (ALD) to apply a thin (5 nm and 10 nm) Al₂O₃ layer onto high-mass loading LFP electrodes. Galvanostatic charge–discharge cycling and electrochemical impedance spectroscopy (EIS) were used to assess the electrochemical performance of coated and uncoated LFP electrodes. The results show that Al₂O₃ coatings enhance the cycling performance at room temperature (RT) and 40 °C by suppressing side reactions and stabilizing the cathode–electrolyte interface (CEI). The coated LFP retained 67% of its capacity after 100 cycles at 1C and RT, compared to 57% for the uncoated sample. Post-mortem analyses, including scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), were conducted to investigate the mechanisms behind the improved performance. These analyses reveal that Al₂O₃ coatings are highly effective in reducing LFP electrode degradation during cycling, demonstrating the potential of ALD Al₂O₃ coatings to enhance the durability and performance of LFP electrodes in LIBs. Full article