Preface

With the growing shortage of global energy and resources, the development of new energy materials has become the focus of worldwide attention. New energy materials through the transformation and utilization of traditional energy (such as solar energy, biomass energy, geothermal energy, wave energy, ocean current energy, and tidal energy, as well as the thermal cycle between the surface and deep layers of the ocean), as well as the development of new energy technologies, effectively solve the energy crisis problem, to achieve sustainable development. They can help to reduce environmental pollution, reduce greenhouse gas emissions, and protect the ecological environment by replacing traditional fossil fuels. For example, the use of renewable energy sources such as solar and wind reduces reliance on fossil fuels, thereby reducing air pollution and carbon emissions. The development of new energy technologies can effectively solve the problem of energy crisis to achieve sustainable development. The research and application of new energy materials require the cross and integration of multiple disciplines, which promotes the development of materials science and other basic disciplines. With the continuous progress of science and technology and the upgrading of industrial structures, the application of new energy materials will be more and more extensive, and the promoting role of economic development will be more and more obvious. The research and development of new materials will continue to promote the development of new energy technologies and provide strong support for solving global energy problems and environmental problems.

As a secondary energy source, electric energy is widely used because it is easy to convert into other forms of energy, such as heat, wind, potential energy, and kinetic energy. Furthermore, it also has the advantages of convenient transmission, easy production and use, clean, safe, and economical. These advantages make electric energy a very important and widely used form of new energy application in modern society. Batteries play a vital role in the supply, storage, conversion, and management of electrical energy; energy storage batteries and power batteries are two important types of batteries. Energy storage batteries are mainly used for the storage of electrical energy, widely used in solar power equipment and wind power equipment energy storage, as well as renewable energy storage; power batteries are mainly used for electric vehicles, electric bicycles, and other mobile equipment to provide power. The development and application of battery materials have greatly promoted the progress of human society, improved people's way of life, and laid a solid foundation for future scientific and technological development and environmental protection.

Batteries consist of positive and negative active materials and other auxiliary materials, which play a key role in the manufacture and performance of batteries. The active material is the core of the electrochemical reaction of the battery, responsible for the storage and release of energy. The auxiliary material provides the necessary structural support and transport pathway for the active material to ensure the smooth progress of the electrochemical reaction. In summary, the active material is the key to the electrochemical performance of the battery, and the auxiliary material provides the necessary structural and transport support for these active materials, which jointly determines the overall performance and application range of the battery.

Auxiliary materials in batteries mainly include separators, conductive agents, binders, current collectors, electrolytes and electrolyte additives, sealing materials, thermal insulation materials, protective layers, and encapsulating materials. The importance of auxiliary materials in batteries is reflected in the following aspects: (1) they can significantly improve the electrical conductivity and mechanical strength of the battery, thereby improving the overall performance and lifespan of the battery; (2) by enhancing the bonding force and stability between the electrode materials, they help to prevent the battery from short circuit and overheating during the charging and discharging processes, thus ensuring the safety of the battery; (3) they can increase the conductivity of the electrolyte, helping to form a stable solid-electrolyte interface film and reduce the burning tendency of the electrolyte, thereby improving the rate performance, low-temperature performance, and the cycle and thermal stability of the battery; (4) they protect the materials in the battery from adverse external factors through various forms, thereby improving the safety, reliability, and service lifespan of the battery. These auxiliary materials play a key role in the production process of batteries, and their performance and selection have an important impact on the performance, lifespan, and safety of batteries. Continuous research and innovation help to improve these auxiliary materials and improve battery performance and reliability. With the development of technology, it is expected that more new materials and auxiliary materials will be used for power batteries in the future.

This book focuses on functional auxiliary materials in batteries; although these components are not a direct source of battery energy, their presence and performance are critical to improving the overall performance of the battery. Organic functional materials and low-dimensional structural materials as the common auxiliary material compositions are widely used in various components of batteries. The first five chapters of this book expand around the application of organic functional materials in batteries, they usually are used as separators, binders, electrolytes, and functional additives. The last two chapters of this book expand around the application of low-dimensional structural materials in batteries, they mainly are used as conductive agents and functional additives. Specifically, the book is divided into the following main chapters:

Chapter 1, Application of Organic Functional Additives in Batteries: Electrolyte additives, as the "fine-tuning agent" in the electrolyte system, can considerably improve the performance of both the electrolyte and the battery through the introduction of a small number of functional additives. There are many kinds of these additives, including film-forming additives, flame retardant additives, high-voltage additives, overcharge protection additives, and so on, which improve the performance of lithium batteries in different aspects, thus significantly improving the overall performance and safety of the battery.

Chapter 2, Application of Biopolymers in Batteries: Biopolymers and their derivative materials bring new development opportunities in batteries due to their unique structures and properties. These materials are of natural origin, have renewable and degradable properties, and show excellent energy storage and conversion potential. These materials have been successfully applied in various battery systems, such as lithium-ion batteries and supercapacitors, through delicate chemical design and optimization, with remarkable results. Biopolymer materials are rich in designability and tunability, and by adjusting factors such as their molecular structure, composition, and morphology, they can precisely regulate and optimize battery performance. This provides a broad space and unlimited possibilities for the future development of the battery field.

Chapter 3, Application of Synthetic Polymers in Batteries: Synthetic polymer materials are widely used in batteries due to their diversity of structure and function. For example, they can be used as binders, electrolyte materials, separators, functional coatings, flame retardants, and active material carriers. Due to the specificity of the molecular structure, each polymer has its own unique physical and chemical properties. The advancement of polymer technology focuses on developing corresponding functions to serve the performance requirements of batteries through rational use of their properties. Through the functional composite of a variety of different polymers or the introduction of inorganic functional materials to modify polymers to achieve functional enrichment and integration, polymer materials can achieve diversified development in battery applications. These applications demonstrate the diversity and importance of synthetic polymers in battery technology, which can further optimize battery performance and drive the rapid development of battery technology through molecular design and materials engineering.

Chapter 4, Application of Nontraditional Organic Ionic Conductors in Batteries: Energy storage batteries play a crucial role in modern society, and the main challenge in this research area is how to efficiently transport ions. Traditional organic electrolytes provide good ionic conductivity; however, they also face some major challenges, especially security risks. Ionic liquids and single-ion conductors are considered promising new organic ionic conductor candidates with higher security. Ionic liquids have outstanding physical and electrochemical properties, including high safety (nonvolatile, nonflammable), wide operating temperature range, wide electrochemical window, high ionic conductivity, and excellent compatibility with electrode materials, all of which are beneficial to battery performance. In addition to their excellent thermal and chemical stability, single-ion conductors are characterized by their extremely high ion transport numbers, as they can selectively transfer only cations or anions....