The successfailure of the microgrid applications depends on how to apply the energy storage end (such as a battery energy storage system) to adjust the consistency between the power source end (such as solar power, ac mains, etc.)the load end (such as air-conditioning, lighting, electrical equipment, etc.). Also, the key for achieving a successful system is to optimize the costperformance simultaneously. The proposed next-generation retired battery energy storage system for microgrids includes saferobust retired battery modules, high-efficiency four-quadrant power conditioners (4Q-PCS),seamless transition control between autonomous islandinggrid-connected modes.

1. 電池平衡電流同充放電電流，且具電池容錯能力。可提前10分鐘估測電池內部溫升，平均誤差小於2。
 
 2. 電力調節器單模組達30kW，可多模組並聯擴充，最高轉換效率 98、功因可調範圍-0.99~0.99。
 
 3. 2周波內可執行完成自主孤島偵測，能於孤島與併網模式間無縫接軌轉換並消除環路電流。

The next-generation retired battery energy storage system with a high safety levelbattery fault tolerance function is proposed for micro-grid, stationary energy storage,electric vehicle industries. In response to the policy of electrifying 16,000 buses in Taiwan by 2030, the proposed technologies can directly assist E-bus companies in using the retired batteries in stationary battery energy systems. This system not only creates maximum circular economy benefits, but also effectively promotes the popularization of microgrids, thereby enhancing the overall power grid resiliencepower supply stability.