Itthipol Udomkitpaibool creator Weerakorn Ongsakul Chairperson Singh, Jai Govind Examination Committee Ekbordin Winijkul Examination committee PEA-AIT Education Cooperation Project Scholarship donor Royal Thai Government Fellowship Scholarship donor text series technical report th Pathum Thani, Thailand Asian Institute of Technology 2019 continuing eng 70 leaves : ill. + 1 online resource The electric vehicles will be used world wild in near future causing a number of second-life batteries in the market. One of the popular second-life battery use is to apply it in microgrids because the new battery energy storage system cost is very high even the global price of battery is decreasing constantly. This study will investigate the second-life batteries performances using in Ban Khun-Pae and Ko-Kood&Ko-Mak microgrids, Thailand as the battery energy storage system. The studies are designed and simulated in PSCADIEMDT software to analyze steady state and transient performances. The results show that the second-life battery energy storage systems can be used properly as new battery energy storage systems in both on-grid and off-grid operations. Moreover, the benefit to cost ratio calculation also shows that applying second life batteries are worthy in both of Ban Khun- Pae and Ko-Kood&ko-Mak microgrids. This study also provides a lot of benefits. The second life battery is lower cost of investment for the new micro grid proj ects that need BES S integration, or microgrids looking for replacing BESS. The lower cost of BESS drives micro grid penetrations in higher rate. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Energy, School of Environment, Resources and Development Thesis (M. Eng.) - Asian Institute of Technology, 2019 Electric vehicles Batteries Service life Lithium ion batteries Microgrids (Smart power grids) Neural networks (Computer science) Computer programs Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B06393 http://203.159.5.9/ait-thesis/detail.php?q=B06393 210205 20260818094018.0