Energy Storage System Components
ESS components are grouped according to function into battery components, components required for reliable system operation, and grid connection components. The battery system consists of the battery pack, which connects multiple cells to appropriate voltage and capacity; the battery management system (BMS); and the battery thermal management system (B-TMS).
The BMS protects the cells from harmful operation, in terms of voltage, temperature, and current, to achieve reliable and safe operation, and balances varying cell states-of-charge (SOCs) within a serial connection. The B-TMS controls the temperature of the cells according to their specifications in terms of absolute values and temperature gradients within the The components required for the reliable operation of the overall system are system control and monitoring, the energy management system (EMS), and system thermal System control and monitoring is general (IT) monitoring, which is partly combined into the overall supervisory control and data acquisition (SCADA) system but may also include fire protection or alarm units.
The EMS is responsible for system power flow control, management, and distribution. System thermal management controls all functions related to the heating, ventilation, and air-conditioning of the containment system.
The power electronics can be grouped into the conversion unit, which converts the power flow between the grid and the battery, and the required control and monitoring components. voltage sensing units and thermal management of power electronics components (fan cooling).
Source: ADB Handbook on battery energy storage technologies