In recent years, with the promotion of dual carbon goals and the transformation of the automotive industry, electrification and intelligence have become new directions for the development of new energy vehicles. According to statistics from the China Association of Automobile Manufacturers, in 2022, the production and sales of new energy vehicles in China continued to grow explosively, with production and sales reaching 7.058 million and 6.887 million respectively, an increase of 96.9% and 93.4% respectively year-on-year, with a significant market growth rate. With the wave of new energy development, the scale of energy storage has been improved. According to CESA data, in 2022, the newly added installation scale of China's chemical energy storage was about 5.93GW, a year-on-year increase of 221.48%, and energy storage has undoubtedly become a fast track for the development of new energy. However, although the large-scale use of renewable energy is a favorable opportunity and key solution to mitigate climate change, these natural energy sources have unstable and intermittent characteristics, with a great impact on load, and pose a great safety risk. As more and more energy storage projects are launched and the scale of energy storage continues to grow, the safety hazards of energy storage are also increasing. Data from the Emergency Management Department shows that in the first quarter of 2023 alone, the spontaneous combustion rate of new energy vehicles increased by 32%, with an average of 8 new energy vehicles catching fire every day. It can be seen that energy storage safety, including batteries, has become a hot topic in the industry. In order to maintain the safe and efficient deployment of energy storage systems, fire safety is an important issue that must be considered, and policies and regulations have also put forward clearer requirements for energy storage fire safety. With the release of the national standard "Safety Code for Electrochemical Energy Storage Power Stations", the implementation of mandatory policies will stimulate the explosive growth of energy storage fire demand. In this regard, technological innovation and product solutions based on electronic and chemical methods have become an important guarantee for improving the safety of energy storage. Recently, the author was invited to visit the National Key Laboratory of Fire Science of the University of Science and Technology of China, and further understood the key technologies and methodologies of the fire laboratory in fire prevention, assessment, and extinguishing, as well as ADI's empowerment, practice, and exploration in the field of energy storage safety.

Approaching the National Key Laboratory of Fire Science of the University of Science and Technology of China

According to Dr. Lu Song, a deputy senior engineer at the fire laboratory of the University of Science and Technology of China, the university proposed the construction of a national fire research center as early as 1987, passed the project demonstration in 1989, was approved for construction and opening to the outside world in 1992, and passed the national acceptance in 1995. In the four national key laboratory assessments in 2003, 2008, 2013, and 2018, it was rated as excellent twice and good twice. In 2004, at the "20th Anniversary of the Implementation of the National Key Laboratory Plan and the 5th Anniversary of the Implementation of the National Key Basic Research Development Plan Memorial Conference", the laboratory was awarded the "Advanced Collective of the National Key Laboratory Plan". Subsequently, the laboratory has made several progress and won multiple awards, and has now become an internationally renowned research base and academic center in the field of basic fire science research. At present, the National Key Laboratory of Fire Science has established 8 research rooms: Building Fire Research Room, Forest and Urban Fire Safety Research Room, Industrial Fire Research Room, Fire Risk Assessment Research Room, Fire Chemistry Research Room, Fire Monitoring and Control Research Room, Clean and Efficient Fire Extinguishing Research Room, and Computer Simulation Research Room; 3 research institutes: Safety Materials Research Institute, Energy Fire Safety Research Institute, and Aerospace Fire Safety Research Institute. The overall positioning of the laboratory is basic research on fire safety - fire science, facing the major national fire safety needs and the frontier of world fire science, committed to the innovation of fire dynamics evolution theory and the principles of key fire prevention and control technology, leading the technological progress of the industry, playing the role of the national fire safety think tank; becoming a research base for continuous scientific and technological innovation, forming a discipline and talent training system with fire mechanism and key prevention technology as the main body; achieving all-round, multi-level domestic and international strong cooperation and scientific and technological cooperation, and continuously occupying an important position in the field of international fire safety science. Through the visit to the scientific research building, fire experiment building, and large space building fire experiment hall, a further understanding of the value and achievements of the fire laboratory of the University of Science and Technology of China in the basic research of fire science and technology transformation was obtained. Among them, the visit to the Forest and Urban Fire Safety Research Room was particularly memorable:

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Through the open environment facing forests, cities, and their boundary areas, scientifically understand the dynamics and macro complexity of fire evolution. At the same time of scientifically understanding the structure of the fire, it also understood the harm of forest fires, which can promote more care for the environment in daily life and reduce the generation of fires.

ADI breaks the situation with technology to meet industry challenges

Firefighting is not only to deal with fires that have occurred, but more importantly, to prevent in advance and eliminate hidden dangers. Taking the aforementioned lithium battery thermal runaway as an example, the early detection of lithium battery thermal runaway is a key link in the field of energy storage firefighting. Behind the prevention and control of fires, the empowerment of electronic technology is indispensable. Smoke detectors are such key equipment, which issue warning reminders as soon as there are signs of suspected fires, winning time for extinguishing and evacuation. At present, photoelectric smoke sensors have become the mainstream fire alarms on the market. It is a mandatory supporting facility for new residential buildings and is likely to be the first step for intelligent firefighting to enter residential communities. In the future, it is expected to become a standard configuration for residential communities and is being accepted and used by more and more people. However, according to statistics from the National Fire Association, even in buildings equipped with smoke detectors, 23% of deaths still occurred when the smoke detectors were not working or were disabled due to frequent false alarms, which brought many severe challenges to the development and use of smoke detectors. To meet this challenge, ADI, with its profound professional knowledge, has developed an intelligent sensing module based on the ADI ADPD188BI dual light source integrated smoke sensor in conjunction with the fire laboratory, which has well solved the technical problems of traditional smoke alarms. According to Wang Junting, Senior System Application Manager of ADI China, ADPD188BI is an integrated smoke sensing solution that combines the analog front end, LED, and photodiode into a compact package, greatly reducing the space occupied by smoke detectors. The integration of the photodiode and AFE also provides high environmental light suppression and a wide dynamic range. ADPD188BI integrates two LED emitters of blue and infrared, using an optimized circuit design of dual light paths, which not only can monitor the concentration of smoke but also can monitor the particle diameter of smoke, thereby distinguishing interfering smoke, such as water vapor, dust, and cooking fumes, and further reducing false alarms.

Smoke detectors with ADPD188BI smoke sensing solution

Wang Junting said that the black plastic part installed above ADPD88BI is called the "maze" in the industry, which is the core module of the intelligent smoke sensor. The "maze" can not only shield the external environmental light signal and provide a stable optical environment for the photoelectric sensor but also help "comb" the flowing smoke particle concentration, improve the resolution and accuracy of the sensor, and accurately determine the type of smoke from the burning object. In addition, ADI also provides an evaluation-licensed smoke chamber to solve the impact of environmental light, dust, insects, etc., and is fully applicable to the integrated photoelectric devices of ADPD188BI using the reverse scattering system. It is worth mentioning that ADI has also developed a smoke detector reference design, including UL217 test data settings and algorithms designed and tested to meet UL requirements, thereby accelerating the development cycle, reducing costs, and project risks. With its high performance and high consistency, ADPD188BI has achieved high scores in the field of firefighting. In addition to the ADPD188BI integrated smoke detector module, combining its own experience in the field of battery management systems (BMS) and high-performance simulation components, ADI has a comprehensive solution for the problem of lithium battery thermal runaway, including sensors for cells/batteries, wireless interconnection solutions for energy storage battery packs, and energy storage management systems for battery clusters and container-type energy storage containers, etc. ADI has a complete intelligent edge and multi-sensor solution.Wang Junting stated that the research on thermal runaway fire monitoring of lithium batteries is a novel field, and collaborating with university laboratories is the optimal choice. As a global high-performance semiconductor company, Analog Devices (ADI) is enthusiastic about collaborating with universities in the field of system-level theoretical research and testing. In addition to providing financial and technical support, ADI engineers are diligently conveying advanced analog electronic design technology, experience, and concepts to teachers and students. Through various forms such as courses, training, competitions, and internships, they have cultivated many talents with innovative and design capabilities. To date, ADI has carried out two phases of collaborative research with Professor Zhang Heping's research group at the University of Science and Technology of China (USTC): 1) The first phase was on the characteristic research of lithium battery fires, helping ADI verify chip performance and system solutions; 2) The second phase was an in-depth analysis of lithium battery thermal runaway events, exploring multi-modal information fusion detection technology for thermal runaway based on smoke detectors. Professor Zhang Heping's research group has long been engaged in research on low false alarm fire detection technology for aircraft cargo compartments and thermal safety of aviation lithium batteries. Through the cooperation of both parties, advanced detection technology in the aviation field will be applied to civil lithium battery detection.

Industry-education integration promotes a new future for the industry

According to data from iResearch Consulting, the market size will reach 446.5 billion yuan in 2022. At the same time, according to relevant notices from the State Council, the application of new technologies such as the Internet of Things is encouraged to improve fire prevention prediction and information acquisition capabilities. Preliminary estimates suggest that the national installation scale of smoke detectors in the next five years is expected to reach 700 million, and the global annual installation scale will exceed 3 billion units, with a very broad market prospect. This trend will bring new development opportunities for both the USTC Fire Laboratory and ADI. Looking ahead, ADI will focus on leading technologies of the future, relying on current lithium battery thermal runaway analysis and research to solve thermal runaway events in advance for perception and early warning. Of course, in addition to direct application fields such as electrochemical energy storage, new energy vehicles, and new energy buses related to lithium batteries, ADI will also focus on solving safety issues in charging piles, battery swapping stations, and high-power electrical switch cabinets, using technological innovation to protect fire safety. In this process, ADI and USTC will continue to promote industry-education integration and maintain close cooperation. ADI collaborates with the first-class team of the National Key Laboratory of Fire Science at USTC to test and verify ADI products and technologies to a high standard, ensuring high precision and reliability of the products. At the same time, ADI provides the National Key Laboratory of Fire Science with cutting-edge chip-level sensors, data, and prototype algorithms, actively cooperating in areas with a high degree of fit and willingness, aiming to further improve the level of fire detection technology and ensure fire safety. "At the same time, in the process of promoting the combination of theory and engineering practice, it also cultivates more outstanding engineers for China's electronic professional education, and contributes to the faster and better development of China's electronic semiconductor industry," said Dr. Lu Song.