Preface

Renewable energy systems have been identified as potential solutions to traditional fossil fuels, which are associated with the emission of carbon dioxide that is not environmentally friendly. The 26th United Nations Climate Change Conference (COP26) in Glasgow, United Kingdom, brought parties together to accelerate actions towards the Paris Agreement and Kyoto Protocol.

With the proliferation of renewable energy and smart grid technologies, the need for energy storage cannot be overemphasized, due to the stochastic nature of renewable energy sources. In renewable energy applications, solar, wind, and hydropower energy sources are considered the most versatile for generating electricity. The high-efficiency power utilization of solar and wind energy, either standalone (autonomous) or gridconnected (non-autonomous), necessitates considerable advancements in energy storage technologies, especially in residential, industrial, solar farm, and wind farm applications, to overcome their intermittent nature.

There are emerging interdisciplinary studies on energy storage technologies for solar-photovoltaic, photothermal, electrical, and thermal energies, wind farm stability, and hydrogen production using battery energy storage systems, flywheels, or other alternative solutions to enhance the continuity and stability of solar and wind energy utilization and efficiency.

This book presents recent works on the concept, design, control, and applications of energy storage devices and techniques in the field of energy conversion and conservation, including electrical and thermal storage for the rapid development and utilization of energy systems. Since the developments in this field are rapid and accompanied by many challenges, this book proposes different techniques considering novel topologies of control and advanced strategies for the optimal performance of energy storage systems.

The book is for graduate and undergraduate students, academics, energy planners, industries, and government establishments in the field of energy storage devices and management.

This book is divided into two sections. The first section includes four chapters considering battery storage techniques. Chapter 1, "Electrical Equivalent Circuit Models of Lithium-ion Battery," helps in understanding the behavior of batteries in order to improve both performance and efficiency. A systematic comparison and analysis using simulation was done to help select an ideal model that best suits a specific application. Chapter 2, "Battery Energy Storage Systems and Rooftop Solar-Photovoltaics in Electric Power Distribution Networks," demonstrates the merits of a rooftop solar-photovoltaic (PV) system employing a battery energy storage system. It analyzes the application of only a battery energy storage system, only a rooftop PV system, a hybrid of the rooftop and battery energy system, and varying levels of the battery energy storage system. Chapter 3, "The Second Life of Hybrid Electric Vehicles Batteries Methodology of Implementation in Ecuador," studies the implementation of second-life NiHm batteries in hybrid vehicles in Ecuador to improve the quality of recycling of elements like battery packs and associated devices and generate a special treatment for their recovery. Chapter 4, "Current Status and Prospects of Solid-State Batteries as the Future of Energy Storage," discusses the specific challenges, design principles, and performance

improvement strategies regarding the cathode, solid electrolyte, and anode employed in solid-state batteries. It emphasizes the various perspectives and outlooks on applications that could benefit from the implementation of solid-state battery systems.

The second section includes four chapters focusing on alternative energy storage techniques. Chapter 5, "Physicochemical Approaches for Thin Film Energy Storage Devices through PVD Techniques," discusses the growth of economical and eco-friendly thin, flexible supercap batteries and their potential in transporting electronic devices and other gadgets. The study of supercap batteries is on the rise to obtain high specific power and energy density along with cycle stability. Chapter 6, "IPMC Based Flexible Platform: A Boon to the Alternative Energy Solution," presents a possible solution to the problems of ionic polymer-metal composite membranes. The ionic polymer–metal composite-based platform was seen as a boon to the alternative energy solution. The presented study examines energy storage applications and the practical characteristics of ionic polymer-metal composite polymer materials in the analogous field. Chapter 7, "Structural, Optical, and Electrical Studies of PAN-Based Gel Polymer Electrolytes for Solid-State Battery Applications," is a study of a polyacrylonitrile (PAN) gel polymer electrolyte system for solid-state battery applications. in recent times, ionic solid conducting polymer electrolytes have been used for active potential components in novel battery technology as electrodes and electrolytes. The results obtained in the study were found to be comparable with existing solutions. Finally, Chapter 8, "Phase Change Materials for Renewable Energy Storage Applications," is of key interest because super thermal properties of advanced materials are required to enhance maximum utilization of solar energy and improve energy and exergy efficiency of the solar absorbing system. Phase change materials have high energy density and potential in flat plate solar collector application for the production of hot water in urban households. Thus, they could be successfully incorporated in integrated and non-integrated flat plate solar collectors.

This book examines new trends of research into energy storage devices as applied in renewable energy and smart grid applications. It also addresses shortcomings in the implementation of energy storage. This volume is a useful reference for readers who wish to familiarize themselves with the newest advancements in energy storage systems.

> **Dr. Kenneth E. Okedu** Visiting Professor, Department of Electrical and Communication Engineering, National University of Science and Technology, Muscat, Sultanate of Oman

> > Adjunct Professor, Department of Electrical and Electronic Engineering, Nisantasi University, Istanbul, Turkey

Section 1
