Safety of Grid-Scale Battery Energy Storage Systems

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4. Battery Energy Storage System Design
Below is a high-level diagram of a typical battery energy storage system:
The storage system is typically organised as follows:
• Individual battery cells are assembled into modules
• Modules are mounted within cabinet racks
• Racks are installed in a container (e.g. 40 foot container)
A storage system can be made up of one or more containers and each container typically stores about 1-5 MWh of energy. The container also contains support systems which manage ventilation, cooling, sensors and fire suppression. These will be described further in later sections.
The image below shows what the inside of a storage container can look like. It is possible to see the separate racks and modules of battery cells.
Batteries are controlled using a Battery Management Systems (BMS). The BMS also manages the support systems. The role of the BMS is detailed further in section 5.4.
At a high-level, there is the Energy Management System (EMS) which takes care of overall power flow and operation of the battery in terms of when to charge, discharge and operate in the market. As the
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