The existing thermal runaway and barrel effect of energy storage container with multiple battery packs have become a hot topic of research. This paper innovatively proposes an optimized system for the development of a healthy air ventilation by changing the working direction of the battery container fan to solve the above problems. Four ventilation solutions based on fan flow direction control are numerically simulated, and their internal airflow distributio. The existing thermal runaway and barrel effect of energy storage container with multiple battery packs have become a hot topic of research. This paper innovatively proposes an optimized system for the development of a healthy air ventilation by changing the working direction of the battery container fan to solve the above problems. Four ventilation solutions based on fan flow direction control are numerically simulated, and their internal airflow distribution and thermal behavior are analyzed in detail. The results show that the heat dissipation effect of optimized solution 4 is significantly better than other solutions, and its average temperature and maximum temperature difference are 310.29 K and 4.87 K. The results are reduced by 1.16 % and 54.36 % respectively compared with the initial scheme. The results show that optimized solution 4 has significantly better heat dissipation than the other solutions, with an average temperature and maximum temperature difference of 310.29 K and 4.87 K respectively, a reduction of 1.16 % and 54.36 % respectively compared to the initial scheme. In summary, the cooling and ventilation solution based on the logical control of the fan direction is feasible and had a certain market prospect due to its simple structure and high economy.••••Flow redistribution can be achieved by changing the direction of the fan.••The entire design does not require any structural changes to the model.••The method in the paper is more effective in terms of temperature uniformity.••Optimization strategy is economical and has good application prospects.Air coolingThermal managementBatteryOptimizationIn recent years, the global power systems are extremely dependent on the supply of fossil energy. However, the consumption of fossil fuels contributes to the emission of greenhouse gases in the environment ultimately leading to an energy crisis and global warming,,,. Renewable energy sources such as solar, wind, geothermal and biofuels provide an effective solution to these problems. Nevertheless, all renewable energy sources have the problem of uneven and discontinuous energy output. In addition, another problem is plaguing the power system. As the demand for electricity from industrial production and residential life rises rapidly, the diurnal peak-to-valley difference in power consumption is increasing. Energy storage systems provide a new path to solve the problem of instability in the output of electricity and the imbalance between peak and valley of electricity supply and demand. They play an important pivotal role in charging and supplying electricity and have a positive impact on the construction and operation of power systems. The typical types of energy storage systems currently available are mechanical, electrical, electrochemical, thermal and chemical energy storage. Among them, lithium battery energy storage system as a representative of electrochemical energy storage can store more energy in the same volume, and they have the advantages of long life, light weight and high adaptability. Therefore, lithium battery energy storage systems have become the preferred system for the co. 2.1. Model descriptionThe energy storage system (ESS) studied in this paper is a 1200 mm × 1780 mm × 950 mm container, which consists of 14 battery packs connected in series and arranged in two columns in the inner part of the battery container, as shown in Fig. 1.Fig. 1. Energy storage system layout.There are 24 batteries in two rows fixed inside the battery pack,as shown in Fig. 2. Thus, the energy storage system consists of 336 LIB cells. The LIBs are square lithium iron phosphate batteries, each with a rated voltage of 3.2 V and a rated capacity of 150 Ah.Fig. 2. Battery pack layout.The energy storage system uses two integral air conditioners to supply cooling air to its interior, as shown in Fig. 3. The structure of the integral air conditioners is shown in Fig. 4. The dimensions of each battery pack are 173 mm × 42 mm × 205 mm and each pack has an independent ventilation strategy, i.e. a 25 mm × 25 mm fan is mounted on the battery pack enclosure.Fig. 3. Fan layout diagram.2.2. Heat generation modelThe thermal characteristics of LIBs in use consist of two main components: heat generation and heat transfer.The heating of the LIBs itself is done by both the.