Research On Thermal Runway And Management Of Lithium-ion Battery Energy Storage Systems

The looming energy crisis and increasingly serious environmental problems have prompted the public to seek new alternative energy sources.With its high yield,repeatable,and green and clean advantages,electricity is likely to become the main energy source of the future.As a carrier for energy storage and utilization,lithium-ion batteries have been widely used in various electronic products,electric vehicles and energy storage systems by virtue of their high energy density,high power density and long cycle life.However,in the process of using lithium-ion batteries,the problem of thermal runaway has greatly hindered people’s steps.Therefore,this paper focuses on the thermal runaway problem of lithium-ion batteries,and analyzes the causes and development steps of thermal runaway of lithium-ion batteries.Two thermal management strategies for lithium-ion batteries are proposed to reduce the risk of thermal runaway,namely,a temperature estimation method based on electrochemical impedance spectroscopy of lithium-ion batteries and a new thermal management platform based on semiconductor refrigeration.The research results of this paper help to understand the various characteristics and specific details of thermal runaway of lithium-ion batteries,and the thermal management strategy proposed can greatly reduce the risk of thermal runaway,and finally achieve the purpose of reasonable and safe use of lithium-ion batteries.Firstly,the causes and development process of thermal runaway of lithium-ion batteries and how to reduce the risk of thermal runaway are introduced in detail in this paper.The inductive pathways and the inductive processes and principles of different factors that may lead to thermal uncontrollability are discussed,and the corresponding standard suggestions are put forward.In addition,various chemical reactions and thermal changes occurred in lithium-ion batteries during thermal runaway are explained in detail to help us recognize the nature of thermal runaway.Secondly,this paper focuses on a Li-ion battery temperature estimation strategy based on electrochemical impedance spectroscopy,and the experimental verification of the strategy,the verification results have a good accuracy,the estimation strategy method has a strong robustness.Electrochemical impedance spectroscopy(EIS)can reflect the electrochemical characteristics of lithium-ion batteries.By identifying the parameters of EIS of lithium-ion batteries,the mapping relationship between battery temperature and EIS is obtained,so as to estimate the battery temperature.With accurate estimation of battery temperature,the battery always works in a reasonable temperature range.Once the temperature is abnormal,immediate warning and start the battery management system emergency treatment,will be thermal runaway nip in the cradle.Finally,this paper also studied a new thermal management platform based on semiconductor refrigeration,the platform is different from the conventional air cooling,liquid cooling and phase change material cooling thermal management methods,with low temperature preheating,high temperature cooling two functions,and high efficiency,the effect is good.