The Sungrow PowerStack ST CS is an all-in-one liquid-cooled battery energy storage system (BESS) designed for medium-to-large C&I applications, that can be configurated both in the 2 hours autonomy version and in the 4 hours version.
The system uses LFP cells rated at 3.2 V/314 Ah, for a nominal capacity of 257 or 514 kWh and a depth of discharge from 0 to 100%. The rated AC output power is 125 kW at 400 V, with a grid voltage range of 340-440 V. The DC/AC power conversion unit achieves an efficiency of up to 98.5%.
The liquid cooling system, managed by an AI algorithm, keeps the cell temperature difference below 2.5°C and cuts daily system heat loss by 33%. The product is pre-assembled and pre-commissioned at the factory, reducing on-site commissioning time.
Safety is ensured by AI-based cell health monitoring with early warning for thermal runaway risk, three-level overcurrent protection (PACK, RACK, PCS), and a fire suppression system with combustible gas, smoke, and heat detectors. The cabinet has an IP55 protection rating and C4 anti-corrosion class as standard (C5 optional), with an operating temperature range from -30°C to 50°C.
Last but not least, the storage is equipped by default with a UPS system for auxiliary power supply. Optional is instead the version without an internal UPS and arranged to connect to an external UPS.
The system supports on-grid, off-grid and automatic switching operation, with grid-forming technology and black start capability. Communication is via Ethernet with Modbus TCP protocol for integration with EMS300CP or with third-party EMS, while remote monitoring is handled through the iSolarCloud platform.
The product is certified to IEC 62619, IEC 63056, IEC 62040, IEC 62477, IEC 61000, and IEC 62933, and can be connected in parallel up to 25 units on-grid or 10 units off-grid.
