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The current paper investigates the cycle cut-off criterion on the thermal performance of the three-layers thermocline thermal energy storage (TES) tank system which is used in concentrating solar power (CSP) plants. The one dimensional transient dispersion-concentric (D-C) scheme is applied to calculate the phase change inside each capsule. Using MATLAB software, the numerical model equations have been figured out. Five different scenarios have been created to investigate the cycle cut-off criterion on the thermal performance of the TES tank. The results indicate that there are two important aspects to assess system performance which are the temperature distribution during the charging/discharging cycles and the time required to achieve equilibrium conditions. These aspects directly affect the overall power and external efficiency of the storage system and play a key role in understanding the system start up properties and provide insight into storage availability when designing the power cycle for CSP applications. It was also noted that the cycle times and the time required to achieve periodic conditions are very sensitive not only to the storage temperature difference but also to the cutting temperature difference. The difference in the duration of the charge cycle and the corresponding discharge cycle can be attributed to the consideration of a similar cut-off standard. [ABSTRACT FROM AUTHOR]

The optimal performance of a Li-ion battery is directly impacted by temperature. In order to control the temperature rise and provide even temperature distributions in the battery pack, a thermal management scheme comprises thin heat sinks with multiple phase change materials (PCMs) and air channels is investigated in this paper. The cooling performance and temperature homogenization of the battery thermal management (BTM) system are carefully studied under various configurations of PCMs. The results show that increasing the air inlet velocity has less effect in suppressing the temperature rise at early discharge stage, but ameliorates as the discharge prolonged to 3600 s. The standard deviation of the temperature (STDV) and maximum temperature of the batteries can be decreased by arranging PCMs with a lower melting temperature at the midsection and a higher melting temperature at the air outlet region of the heat sinks. In addition, for volume fraction of PCMs, Case IV, having a PCM with a higher melting point adjacent to the air outlet region and occupying one-half the height of the heat sink, illustrates a lower temperature rise and decreases the maximum temperature in the battery module by 1.024 K, 2.186 K, and 2.553 K, compared to Case I, II, and III, respectively. • Multiple PCMs incorporated thin heat sinks for battery thermal management is proposed. • The thermal performance of the battery based on maximum temperature upsurge is investigated. • The distributions of PCMs based on melting point and latent heat were carefully explored. • The optimal design for the distribution of PCMs is obtained for the proposed battery. [ABSTRACT FROM AUTHOR]

This work presents a numerical investigation of the integration of conventional parallel air-cooling battery system with multi-phase change materials (PCMs) to improve the cooling effectiveness at low power consumption (P c) rate. The study considers various cells partitioning of the PCMs on nine different parallel air-cooled battery packs. The impact of PCMs pattern schemes, inclination angle of the manifold, and air inlet velocity are analysed by employing finite volume technique coupled with an enthalpy-porosity method. Compared with a typical parallel air-cooling system, despite 90% reduction in the air inlet velocity, the integrated system successfully lowers the maximum temperature (T max) by 12.0 K and improves uniformity of temperature distribution based on standard deviation (SDV) of temperature field by 43.9%. Subsequently, inclining the air inlet manifold to an angle close to vertical leads to a poor cooling performance. Also, a proper pattern of PCMs cells partitioning having a trapezoidal cell shape at the top and bottom, and a parallelogram cell shape at the midsection exhibits a better heat dissipation performance. Moreover, compared to the module with highest inlet velocity of 1.5 m/s, reducing the inlet velocity by 66.7% still controls T max at 313.13 K which is well below the critical limit, and decreases the P c by 65.8%. • A comprehensive analysis of integrated traditional parallel air-cooled BTMS is presented. • Thermal performance of the modified battery module based on patterns of PCMs cell partitioning, inclination angle of manifolds, and low airflow rate was investigated. • The effect of various evaluation parameters on thermal behavior are presented. • The cooling effectiveness is remarkably improved. • The optimal pattern of multi-PCMs cells partitioning is obtained. [ABSTRACT FROM AUTHOR]