Grid Battery Storage Container

Overview

The grid battery storage container is a utility-scale battery energy storage system (BESS) packaged inside a single 20 ft ISO shipping container. It stores roughly 3.7 MWh of electricity in lithium-iron-phosphate cells and exchanges up to 1.5 MVA with the grid, providing peak shaving, frequency regulation, renewable firming, and backup. LFP chemistry is chosen for its thermal stability and long cycle life, at the cost of lower energy density than nickel-based cells.

Energy is held in six floor-standing Battery Rack units. Each rack stacks eight modules of sixteen prismatic 3.2 V / 280 Ah cells, giving a nominal DC bus near 1331 V. Rack outputs are combined by the High-Voltage DC System, which carries the high-current DC bus through contactors, fuses, and a lockable manual service disconnect to the power stage.

How it works

The Power Conversion System is a bidirectional grid-tie inverter built on an IGBT bridge with an LCL output filter. It converts battery DC to grid-synchronous AC when discharging and rectifies grid AC to charge the packs, following dispatch setpoints to within milliseconds for frequency response.

Cell, module, and rack data flow up to the Master BMS Controller, which tracks state of charge, balances cells, enforces voltage and temperature limits, and opens the DC contactors on any fault. Site-level scheduling, metering, and grid communication run from the Energy Management Cabinet, which coordinates the PCS and BMS against grid signals and a revenue-grade meter.

Because LFP cells degrade and can vent if overheated, the Thermal Management System loop circulates chilled glycol through cell cold plates to hold a tight temperature band, with electric heaters for cold starts. Safety is layered: the Fire Suppression System system watches for battery off-gassing and hydrogen with electrochemical detectors and discharges a clean agent before thermal runaway can propagate. The whole assembly sits in a rock-wool-insulated steel Container Enclosure with bonded grounding and emergency egress.