On September 5, local time, a container battery energy storage system caught fire in Escondido, California, USA. The head of the local fire department said that spraying water on the already burning energy storage battery may make the problem worse, so their intervention measures are mainly concentrated in the area around the fire, which is in line with the current best practices for dealing with lithium battery fires. In the best case, the fire will extinguish itself in about 12 hours, and in the worst case, it will be about 48 hours.
It is reported that the energy storage facility was built in 2017 and uses AES' Advancion energy storage system. With a capacity of 30MW/120MWh, it was the largest battery energy storage power station in the world at that time. The fire accident caused more than 500 companies to be evacuated and many nearby schools to suspend classes. Although technicians measured atmospheric readings within 5 feet of the accident site and said they found no abnormal readings indicating that toxic smoke reached abnormal levels, local residents were still panicking. Another source said that the energy storage system that caught fire this time used ternary lithium batteries. In this regard, many people in the industry said that it was expected. Analyzing various energy storage fire accidents overseas in recent years, ternary lithium batteries have appeared frequently. Judging from the market situation, the domestic mainstream technology route has switched to lithium iron phosphate technology, but there are still a large number of ternary lithium battery energy storage systems being put into use overseas. A hell joke in the industry about overseas ternary lithium batteries is very apt: A: In a few years, there will be no need to worry about the energy storage system catching fire. B:Why? A: Because the ternary lithium battery is safe once all the energy stored in it is burned out. A staff member of an energy storage company admitted that although the current safety performance of ternary lithium is unsatisfactory, we should not be overconfident in lithium iron phosphate. After all, there are many energy storage systems that use lithium iron phosphate batteries that have caught fire. Although the industry continues to strengthen the safety prevention and control of lithium battery energy storage in various fields such as cells, batteries, systems, temperature control, fire protection, etc., it is also actively exploring other more reliable alternative solutions . However, it is still "just a short distance" from true absolute safety. At the same time, affected by the decline in the price of lithium raw materials , the development of sodium electric energy storage has also encountered bumps. Although after repeated weighings, the market finally chose the lithium iron phosphate energy storage system, the supporting safety industry has also developed. However, the constant reports of various lithium battery fire accidents continue to strain the nerves of practitioners. How can we make energy storage systems safer? This question tortures all participants from academia to the market, from users to R&D. On the other side of the spread of anxiety, other niche energy storage technology routes such as flow battery energy storage, OPzV solid-state lead battery energy storage and carbon dioxide energy storage are developing "uniquely". Flow batteries use water as the electrolyte solvent for energy storage. Water itself is non-flammable and flame-retardant, so the electrolyte has no risk of combustion and explosion, so it has intrinsically safe properties. From the perspective of operating principles, the electrochemical reaction and the entire charging and discharging process of the flow battery occur under aqueous conditions. There is no risk of combustion and explosion, ensuring absolute safety. According to the "2024 China Flow Battery Industry Development White Paper" released by the Energy Storage Application Branch of the China Chemical Physics Power Industry Association, it is estimated that my country's flow battery production capacity is expected to jump to 30GW/year in 2025. The OPzV solid-state lead battery uses nanoscale fumed silica as the electrolyte. It is a 100% solid structure with no liquid and no leakage, effectively solving the safety problem of battery thermal runaway and fire. At present, overseas OPzV solid-state lead battery energy storage systems have been operating safely and stably in special scenarios such as large databases and computer rooms. The carbon dioxide energy storage system consumes renewable energy surplus power or off-peak power to drive a compressor to produce high-pressure carbon dioxide gas, liquefies it and stores it in a pressure vessel, and stores the compressed heat energy in the heat storage medium. In the power generation process, liquid carbon dioxide absorbs compression heat energy and becomes gaseous before entering the expander to generate power. Carbon dioxide energy storage has significant economic advantages, and there is no risk of combustion or explosion in terms of safety. An executive of an energy storage company said: "In fact, many niche technology routes have a 'crushing advantage' in terms of safety compared to lithium batteries. But compared to the absolutely mainstream lithium battery energy storage system, the popularity and awareness of other technology routes is indeed However, with the occurrence of various energy storage fires and deflagration accidents, companies that feel anxious and anxious may take the initiative to think outside the box, and other energy storage technology routes will also gain important development opportunities."