Charge-discharge characteristics improvement through optimization of voltage range for LiNiCoMnO2 electrode for high energy density lithium-ion batteries

The development of suitable electrode materials for lithium ion batteries (LIBs) to enhance the performance of LIBs in order to meet increasingly demand globally is one of the challenges. Thus, for almost three decades since 1980, continuous study for high performance LIBs electrode has been done. In this report, the optimization charge-discharge characteristic of LiNiCoMnO2 (LNCM) cathode – layered structured material with lithium metal as anode has been evaluated. The electrode was assembled together with Celgard as separator and organic electrolyte Lithium hexafluorophosphate (1M LiPF6, EC:DEC 1:1) in coin cells (CR2032) under argon atmosphere inside a glove box. The charge-discharge performance test was conducted using Neware battery testing system. The discussion in this paper is focusing on the characteristic features of the charge-discharge profile, optimize charge-end voltage and rate capability (C-rate). The studies discovered the voltage range has been optimized up to 3.3-4.5 V at a constant current of 0.35 mA (0.1 C) with voltage plateau of 4.0 V. The result indicated the optimized range has the highest specific capacity of 118 mAh/g and most stable coulombic efficiency (94.3%)

Synthesis and electrochemical characterizations of poly(3,4-ethylenedioxythiophene/manganese oxide coated on porous carbon nanofibers as a potential anode for lithium-ion batteries

Poly(3,4-ethylenedioxythiophene)/manganese oxide coated on porous carbon nanofibers (P-CNFs/PEDOT/MnO2) is developed as an advanced anode material via the innovative combination of multiple routes, such as electrospinning, carbonization and electrodeposition. The structural and morphological characterization of the P-CNFs/PEDOT/MnO2 electrode indicates that crosslinked and rough surface provides, as a strategic point, enough active sites for Li+ storage. PEDOT nanoparticles and irregular block shape of MnO2 are randomly oriented on the P-CNFs surface, thus allowing a possible electron-conducting pathway, increment in catalytic activity as well as a buffer of the volumetric changes upon cycling. Consequently, the obtained P-CNFs/PEDOT/MnO2 electrode exhibits a truly promising electrochemical performance, which displays discharge capacity of 1477 mAh/g, better than that of P-CNFs/PEDOT (1191 mAh/g), P-CNFs/MnO2 (763 mAh/g) and P-CNFs (433 mAh/g), at a current density of 2 mA/g. In addition, satisfactory electrochemical performances of the as-prepared P-CNFs/PEDOT/MnO2 electrode after 20 cycles of charge/discharge are detected, with a Coulombic efficiency higher than 90% and a charge-transfer resistance being relatively smaller (131.91 ohm) than that of P-CNFs/PEDOT (232.66 ohm) and P-CNFs/MnO2 (169.17 ohm) electrodes. Thus, these results indicate that the P-CNFs/PEDOT/MnO2 electrode could offer a great potential to replace commercial graphite for lithium-ion batteries

Kesan masa prarawatan terma bagi penghasilan karbon keras berasaskan sekam padi untuk aplikasi bateri ion natrium

Sekam padi merupakan sisa biojisim yang memiliki potensi untuk digunakan dalam pembuatan elektrod karbon keras di dalam bateri ion natrium (SIBs). Bahan ini memiliki permukaan spesifik yang luas dan kapasiti menyimpan tenaga teori yang tinggi. Dalam kajian ini, kesan variasi masa prarawatan terma yang berbeza dijalankan terma dijalankan ke atas sekam padi sebagai sumber karbon keras untuk aplikasi bahan anod dalam SIB. Analisis spektroskopi Raman dan CHNSO telah dilakukan untuk menentukan sifat kimia manakala struktur karbon keras dikaji dengan pembelauan sinar-X (XRD). Ukuran saiz, luas permukaan liang, purata diameter dan isi padu liang telah dilakukan melalui analisis saiz zarah dan jerapan fizikal. Keputusan menunjukkan bahawa tempoh masa prarawatan terma mempunyai kesan yang signifikan terhadap sifat karbon keras. Masa rawatan terma optimum didapati adalah 40 jam (sampel RH2) dan mempunyai luas permukaan spesifik dan komponen karbon tertinggi iaitu 1059.02 m2 g−1 dan 78.0% masing-masing dengan saiz zarah berdiameter 15.0 µm. Luas permukaan ini adalah hampir empat kali ganda nilai yang diperolehi daripada kajian sebelum. Dijangkakan sampel ini dapat menghasilkan lebih tinggi kapasiti penyimpanan tenaga dan kinetik semasa operasi SIB kerana peningkatan luas permukaan dan tapak aktif

Development of battery management systems (BMS) for electric vehicles (EVs) in Malaysia

Battery Management Systems (BMS) is an electronic devices component, which is a vital fundamental device connected between the charger and the battery of the hybrid or electric vehicle (EV) systems. Thus, BMS significantly enable for safety protection and reliable battery management by performing of monitoring charge control, state evaluation, reporting the data and functionalities cell balancing. To date, 97.1% of Malaysian CO2 emissions are mainly caused by transportation activities and the numbers will keep rising as numbers of registered car increase close up to 1 million yearly; double the amounts in the last two decades. The uncertainty of a battery’s performance poses a challenge to predict the extended range of EVs, which need BMS implementation of optimization of optimum power management. Hence, using MATLAB/SIMULINK software is one of the potential methods of BMS optimization with power generated by Hybrid Energy Storage system of lithium-ion battery. Therefore, this paper address through reviewing previous literatures initially focuses on the BMS optimization for EVs (car) in Malaysia as prognostic technology model improvement on performance management of EVs

Development of battery management systems (BMS) for electric vehicles (EVs) in Malaysia

Battery Management Systems (BMS) is an electronic devices component, which is a vital fundamental device connected between the charger and the battery of the hybrid or electric vehicle (EV) systems. Thus, BMS significantly enable for safety protection and reliable battery management by performing of monitoring charge control, state evaluation, reporting the data and functionalities cell balancing. To date, 97.1% of Malaysian CO2 emissions are mainly caused by transportation activities and the numbers will keep rising as numbers of registered car increase close up to 1 million yearly; double the amounts in the last two decades. The uncertainty of a battery’s performance poses a challenge to predict the extended range of EVs, which need BMS implementation of optimization of optimum power management. Hence, using MATLAB/SIMULINK software is one of the potential methods of BMS optimization with power generated by Hybrid Energy Storage system of lithium-ion battery. Therefore, this paper address through reviewing previous literatures initially focuses on the BMS optimization for EVs (car) in Malaysia as prognostic technology model improvement on performance management of EVs

Free-Radical Photopolymerization of Acrylonitrile Grafted onto Epoxidized Natural Rubber

The exploitation of epoxidized natural rubber (ENR) in electrochemical applications is approaching its limits because of its poor thermo-mechanical properties. These properties could be improved by chemical and/or physical modification, including grafting and/or crosslinking techniques. In this work, acrylonitrile (ACN) has been successfully grafted onto ENR- 25 by a radical photopolymerization technique. The effect of (ACN to ENR) mole ratios on chemical structure and interaction, thermo-mechanical behaviour and that related to the viscoelastic properties of the polymer was investigated. The existence of the –C≡N functional group at the end-product of ACN-g-ENR is confirmed by infrared (FT-IR) and nuclear magnetic resonance (NMR) analyses. An enhanced grafting efficiency (~57%) was obtained after ACN was grafted onto the isoprene unit of ENR- 25 and showing a significant improvement in thermal stability and dielectric properties. The viscoelastic behaviour of the sample analysis showed an increase of storage modulus up to 150 × 103 MPa and the temperature of glass transition (Tg) was between −40 and 10 °C. The loss modulus, relaxation process, and tan delta were also described. Overall, the ACN-g-ENR shows a distinctive improvement in characteristics compared to ENR and can be widely used in many applications where natural rubber is used but improved thermal and mechanical properties are required. Likewise, it may also be used in electronic applications, for example, as a polymer electrolyte in batteries or supercapacitor

Progress towards highly stable and lead-free perovskite solar cells

High-performance perovskite solar cells have attracted increased attention for photovoltaic applications and potentially replacing the predecessor generations. Nevertheless, the stability issues and the lead content has always been among the major concerns that barriers perovskite solar cells from commercialization. This review presents the discussion towards the inherent instability of perovskite solar cells and the development towards replacing lead with discussion towards their performance and challenges. The degradation of perovskite active layer would release toxic substance into the environment. The development towards low-toxic, lead-free and efficient perovskite solar cells is the key for a sustainable solar energy generation with the application of perovskite solar cells