در مطلب محاسبات نرم چیست ابتدا مفهوم محاسبات (رایانش) شرح داده شده است و سپس، به تعریف مفهوم محاسبات سخت و معرفی محاسبات نرم به بیانی ساده پرداخته و در مورد خصوصیات بارز آن توضیحات بیش‌تری داده شده است. در پایان نیز برخی کاربردهای محاسبات نرم بیان شده است.
Potential of lithium-ion batteries in renewable energy
a b s t r a c t
The potential of lithium ion (Li-ion) batteries to be the major energy storage in off-grid renewable energy is presented. Longer lifespan than other technologies along with higher energy and power densities are the most favorable attributes of Li-ion batteries. The Li-ion can be the battery of first choice for energy storage. Nevertheless, Li-ion batteries to be fully adopted in the renewable energy sector need a price reduction that most likely will be due to the mass production. The progress in Li-ion batteries needs to be carried further to match enough energy and power densities for the electric vehicle. We present the electric vehicle sector as the driving force of Li-ion batteries in renewable energies. We believe that the development of the electric vehicle industry could be the driving force for the renewable sector making Li-ion batteries more affordable as a benefit of mass production. In the development of Li-ion technology, the electric automobile will be accompanied by other sectors such as grid storage, consumer electronics, the electric bike, military or other medical applications. We present the incomparable advantages of Liion batteries over other technologies even if some challenges are still to overcome for a wider usage in stationary energy storage.
MULTIFUNCTIONAL MODULE LITHIUM-IONSTORAGE AND PHOTOVOLTAlC CONVERSION OF SOLAR ENERGY
چکیده ترجمه:
حجم عظیمی از تحقیقات انجام شده در زمینه ی فتوولتاییک (انرژی الکتریکی حاصل از تابش نور) به گسترش ابداعات و خلاقیت ها در زمینه تکنولوژی مدل پایه اختصاص یافت است. اکنون کاربرد یک تابع ذخیره ساز انرژی بعنوان یک منبع تأمین توان الکتریکی غیر دائمی که بتواند بین بکارگیری منبع انرژی و تولید آن تعادل برقرار کند مدنظر است. یک سیستم فتوولتاییک در صورتی پدید می آید که تمام قسمت های تشکیل دهنده آن از جمله: صفحه خورشیدی، باتری، مبدل ها، بخش کنترلی الکتریکی و کابلها در یک مجموعه ی واحد کنار هم قرار بگیرند.
Maximum power point tracking and optimal Li-ion battery charging control for photovoltaic charging system
a b s t r a c t
Due to the severity of the global energy crisis and environmental pollution, the photovoltaic (PV) system has become one kind of important renewable energy source. Solar energy has the advantages of maximum reserve, inexhaustibleness, and is free from geographical restrictions, thus making PV technology a popular research topic. This study is aimed at developing a PV charging system for Li-ion batteries by integrating Maximum Power Point Tracking (MPPT) and charging control for the battery. In order to enable the solar cell to use the sunlight effectively, a DC/DC boost converter for solar power generation was first designed, which used the MPPT Algorithm of Variable Step Size Incremental Conductance Method (INC) to enable the solar cell to track the MPPT at any time. The output from the DC/DC boost converter then entered the DC/DC buck converter to reduce the voltage for charging purposes. The charging system uses a constant voltage method to charge the Liion battery. The PI controller design Constant Voltage (CV) charging method uses a genetic algorithm to determine the optimal gain value. The numerical simulation showed that the PV charging system proposed by this study is easily realized, and can resist the disturbance of external environmental changes, and achieve fast charging.
Lithium-ion battery-packs for solar home systems: Layout, cost and implementation perspectives
A B S T R A C T
Solar home systems provide effective power supply solutions for off-grid households in developing regions. The standard battery in such systems is currently lead-acid. Nevertheless, recent and foreseeable developments in lithium-ion batteries favor their use in such application, resulting in significant advantages, including light and compact layout, outstanding performance, reliable operation and long cycle life. This paper explores this implementation potential by detailing the engineering aspects of lithium-ion battery-packs for solar home systems, and elaborating on the key cost factors, present and future. It is concluded that the technology is mature for the solar home system market. Furthermore, despite the relatively high initial cost, the lithium-ion battery is competitive at the level of energy storage cost. Ongoing cost reductions will favor the accelerated use of lithiumion batteries in this application. More favorable conditions to reduce implementation barriers would be created via tailored funding programs and financing schemes.
Lithium-Ion Battery Storage for the Grid—A Review of Stationary Battery Storage System Design Tailored for Applications in Modern Power Grids
Abstract: Battery energy storage systems have gained increasing interest for serving grid support in various application tasks. In particular, systems based on lithium-ion batteries have evolved rapidly with a wide range of cell technologies and system architectures available on the market. On the application side, different tasks for storage deployment demand distinct properties of the storage system. This review aims to serve as a guideline for best choice of battery technology, system design and operation for lithium-ion based storage systems to match a specific system application. Starting with an overview to lithium-ion battery technologies and their characteristics with respect to performance and aging, the storage system design is analyzed in detail based on an evaluation of real-world projects. Typical storage system applications are grouped and classified with respect to the challenges posed to the battery system. Publicly available modeling tools for technical and economic analysis are presented. A brief analysis of optimization approaches aims to point out challenges and potential solution techniques for system sizing, positioning and dispatch operation. For all areas reviewed herein, expected improvements and possible future developments are highlighted. In order to extract the full potential of stationary battery storage systems and to enable increased profitability of systems, future research should aim to a holistic system level approach combining not only performance tuning on a battery cell level and careful analysis of the application requirements, but also consider a proper selection of storage sub-components as well as an optimized system operation strategy.
Efficiently photo-charging lithium-ion battery by perovskite solar cell
Electric vehicles using lithium-ion battery pack(s) for propulsion have recently attracted a great deal of interest. The large-scale practical application of battery electric vehicles may not be realized unless lithium-ion batteries with self-charging suppliers will be developed. Solar cells offer an attractive option for directly photo-charging lithium-ion batteries. Here we demonstrate the use of perovskite solar cell packs with four single CH3NH3PbI3 based solar cells connected in series for directly photo-charging lithium-ion batteries assembled with a LiFePO4 cathode and a Li4Ti5O12 anode. Our device shows a high overall photo-electric conversion and storage efficiency of 7.80% and excellent cycling stability, which outperforms other reported lithium-ion batteries, lithium–air batteries, flow batteries and super-capacitors integrated with a photo-charging component. The newly developed self-chargeable units based on integrated perovskite solar cells and lithium-ion batteries hold promise for various potential applications.
Lithium Ion Battery
Discover Advanced Energy (AES) batteries allow for equipment design and functionality improvements and deliver productivity gains through enhanced cycling, charge time and weight reductions in stationary and mobile applications. Dramatic improvements in cycle life and charge efficiency combined with zero maintenance requirements provide the end user with significant cost of ownership savings.
Design considerations and performance evaluation of outdoor PV battery chargers
abstract
Two main challenges are encountered in photovoltaic (PV) based battery chargers, namely, the variable input power and the fluctuating temperature. As a result, traditional charging techniques that rely only on the terminal measurements such as the current, voltage or temperature are not reliable in those chargers. Furthermore, relying only on the terminal measurements without other indirect measurements can result in terminating the charge before the battery is truly fully charged, which has several drawbacks such as reducing the usable capacity and possibly leading to memory effect in nickel-based batteries, or overcharging the battery which can lead the battery to prematurely reaching its end-of-service. This paper presents design considerations and evaluates the performance of PV chargers used to charge major battery chemistries including nickelecadmium (NiCd), nickel-metal-hydride (NiMH), lithium-ion (Li-ion) and sealed lead-acid batteries at real operating conditions.
Comparison the economic analysis of the battery between lithium-ion and lead-acid in PV stand-alone application
Abstract
This paper presents the economics analysis of 140 Wp photovoltaic (PV) stand-alone system by using a generic excel model. The main components of PV stand-alone system consist of 140 Wp PV module, 150 W inverter, and two different types of battery as lithium-ion and lead-acid battery. The economic analysis of this paper presents the cost of energy (COE), benefit cost ratio (BCR), and simple net present value (SNPV). From the results of this study show that the COE, BCR, and SNPV of PV standalone system, which using lithium-ion battery are 0.13, 34.93 baht/kWh and 145,927 baht, respectively. For the COE, BCR, and SNPV of PV stand-alone system, which using lead-acid battery are 0.19, 23.30 Baht/kWh and 89,143 Baht, respectively. Although the economic parameters show that the PV stand-alone which using lead-acid batteries is suitable than PV stand-alone that used lithium-ion battery. However, lithium-ion batteries have many advantages when compare with lead-acid battery technology as high energy density, low maintenance and the number of lifecycle is higher compared with lead-acid battery.
