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© 2022 John Wiley & Sons Ltd.Thanks to today's developing technology, lithium-ion batteries in commercial use have become important components in energy storage systems and electric vehicles. In lithium-ion battery-based systems, it is especially important that the electrochemical structures of electric vehicle batteries and rapid charging process as allowed by the manufacturers. In other respects, it is necessary to define the best quality, fastest and healthiest charging method within the limited time period determined in line with user requests. In this study, an intelligent charging algorithm is designed and adapted to the problem for optimizing the charging current capacity and charging time for INR 18650 cylindrical type 2000 mAh Li-NMC battery cells, taking into account the manufacturer's notes and the characteristics of the battery cells. To determine the optimum fast charging method by completing the total charging time within 30 min, the multi swarm-particle swarm optimization technique with both fixed and dynamic internal weights has been used. The algorithm with dynamic state variables has showed an average improvement of 0.03% and a maximum of 1.08% in the cellular chargeable capacity value, according to the test data consisting of 11 pulses and 1 A constant current. Otherwise, the algorithm with dynamic internal weights has achieved an average improvement of 1.14% and a maximum of 2.21% when compared to the fast charging information on the manufacturer's information page using the constant current-constant voltage method. Considering the 50-minute fast charging data in the manufacturer's information notes, the algorithm with dynamic weights improved the charging time by approximately 54.4%. As a result of running the dynamic weighted algorithm, a maximum improvement of 0.06% in terminal voltage and 0.92% in the state of charge value has been observed. When hundreds of cells in electric vehicle battery blocks and mobile energy storage systems come together, this increase provides significant energy savings. Similar to the increase in charging capacity, an improvement in equilibrium voltage, charging efficiency and state of charge has been also detected at the end of the charging process. Consequently, the method in the study has provided high charging capacity in a shorter time, while keeping the energy efficiency at high levels.

Güneş enerjisi (GE), küresel çevre endişelerini azaltmak ve artan enerji talebini karşılamak için en umut verici yenilenebilir enerji kaynaklarından biri olmuştur. Güneş enerjisinden farklı şekillerde yararlanılmaktadır. Bunlardan biride fotovoltaik (PV) hücrelerdir. Fotovoltaik hücreler güneş enerjisini doğrudan elektrik enerjisine dönüştüren yarıiletken malzemelerdir. Geleneksel fotovoltaik modüller tam PV hücreler ile modellenmektedir. Günümüzde ise yeni bir teknoloji olan yarım hücreli modül kullanımı hızla artmaktadır. Yarım PV hücrelerin tam PV hücrelere göre çeşitli avantajları olmasına rağmen, bazı üretim dezavantajları da vardır. Bu çalışmada kapsamlı bir literatür incelemesi sonucu yarım ve tam hücreli PV modüllerin toplam verimliliğini etkileyen parametreler karşılaştırılarak yarım hücreli PV modüllerin, düşük güç kaybı, azaltılmış gölge duyarlılığı, fiyat performans oranının yüksek olması, daha az sıcak nokta etkisi ve iyileştirilmiş ısı dağılımı gibi tam hücrelere göre üstünlüklerinin gösterilmesi amaçlanmaktadır. Bunlara ek olarak yarım ve tam PV hücrelerinin verimlilikleri, üretim süreçleri ve diğer bazı dezavantajları hakkında da bilgiler verilmektedir., Solar power (SP) has been one of the most promising renewable energy sources to alleviate global environmental concerns and meet growing energy demand. Solar energy is used in different ways. One of them is photovoltaic (PV) cells. Photovoltaic cells are semiconductor materials that convert solar energy directly into electrical energy. Conventional photovoltaic modules are modeled with full PV cells. Today, the use of half-cell modules, which is a new technology, is increasing rapidly. Although half PV cells have several advantages over full PV cells, there are also some manufacturing disadvantages. In this study, as a result of a comprehensive literature review, the parameters affecting the total efficiency of half and full cell PV modules are compared. With this comparison, it is aimed to show the advantages of half-cell PV modules over full-cells, such as low power loss, reduced shade sensitivity, high price-performance ratio, less hot spot effect and improved heat dissipation. In addition to these, information is given about the efficiency, production processes and some other disadvantages of half and full PV cells.

In this study, a low-voltage low-power, simple operational transconductance amplifier (OTA) based fractional order low-pass and high-pass filters of order (n+alpha) are designed and simulated with CADENCE-PSPICE where 0= 1. The employed transconductance amplifier operates at +/- 0.75 V. To simulate designed filters, 0.35 mu m TSMC CMOS technology parameters are used. The simulation results verify theoretical statements. The power dissipations of simulated low-pass filters of orders 1.3, 1.5, 2.3 and 2.5 are 14.6 nW, 13 nW, 17 nW and 15.3 nW, respectively. For the same filter orders, the corresponding dissipation values of high-pass filters are respectively 45.2 nW, 42.7 nW, 47.5 nW and 45 nW. In addition to the low-power low-voltage operation, another significant advantage of the proposed circuit topologies is that the OTA based low-pass and high-pass topologies provide electronic tuning capability of the orders and frequency responses of the filters without any structural change on these topologies. Therefore, same circuit topology can be used for the different orders of the same filter by just changing the biasing currents of the used OTAs. Additionally, OTA-C based filters offer usage of the grounded capacitors as well as resistorless realization.

Enerjinin üretim ve tüketimi, ülkelerin gelişmişlik düzeyini ölçmede kullanılan uluslararası en geçerli göstergelerden biri olarak görülmektedir. Sürekli artan enerji ihtiyacını karşılamada, mevcut kaynakların rezervi ne kadar çok olsa da, bu kaynakların Dünya’da mevcut bulunan miktarı ile sınırlı olduğu kaçınılmaz bir gerçektir. Günümüzde, bu kaynaklardan üretilen enerji miktarının, yaşadığımız bilgi ve uzay çağının ihtiyacını karşılamakta yetersiz kalması sonucunda alternatif enerji kaynaklarını bulma ve geliştirme çalışmaları hız kazanmaktadır. Bu çalışmada, alternatif enerji kaynağı arayışı sonucunda önemi gün geçtikçe artan rüzgar enerjisi ve elektrik enerjisi üretmede kullanılan türbin sistemleri incelenirken, ülkemizin mevcut rüzgar enerjisi potansiyeli verilerle desteklenerek analiz edilmektedir. The production and consumption of energy is seen as one of the most international indicators used to measure the level of development of countries. In meeting the ever-increasing need for energy, the reserves of available resources are inevitable, though these resources are limited to what is available on Earth. Today, as the amount of energy generated from these sources is inadequate to meet the needs of information and space age we live, efforts to find and develop alternative energy sources are accelerating. In this study, in a result of the search for alternative energy sources, day by day inportance of things that wind power is increasing and the turbine systems used to generate electric energy is investigatig.

Fosil kaynakların sınırlı olması enerji üretim maliyetlerini ve dışa bağımlılığı artırmaktadır. Diğer taraftan, geleneksel enerji üretim yöntemleri bugün çevre kirliliğinin önemli nedenlerinden biridir. Bu sebeple, yenilenebilir enerji kaynaklarının ve enerji depolama sistemlerinin (EDS) önemi giderek artmaktadır. Bu çalışmada, batarya teknolojileri içerisinde yer alan, Vanadyum Redox teknolojisinin ve Lityum tabanlı batarya teknolojisinin enerji depolama sistemleri içerisindeki kullanımı hakkında bilgi verilirken, Li-FePO4 tabanlı enerji depolama sistemleri üzerine yapılan test sonuçları değerlendirilmektedir Limited fossil resources increase the cost of energy production and external dependency. On the other hand, today, traditional energy production methods are one of the important causes of environmental pollution. Therefore, the importance of renewable energy sources and energy storage systems (ESS) are increasing. In this study, the results of testing on Li-FePO4 based energy storage systems are evaluated while informing about the usage of Vanadium Redox technology and Lithium based battery technology in energy storage systems