According to a report by the National Renewable Energy Laboratory (NREL), with constant battery unit capacity costs, the larger the total capacity of the energy storage system, the lower the other costs allocated to each unit of capacity. This makes Battery Energy Storage Systems (BESS) increasingly advantageous in large-capacity energy storage applications, as shown in the table below.
Cost breakdown of a lithium-ion battery energy storage system
Specifically, the cost breakdown for the manufacturing, installation, and commissioning of containerized BESS (Battery Energy Storage Systems) is shown in the table below.
BESS Cost Proportion Distribution (Table 2-4)
| BESS Parameter | Container/ Enclosure | Electrical | Structure | Temperature Control | Fire Protection | PCS (Inverter) | Battery Cells |
|---|---|---|---|---|---|---|---|
| 50kW/2h | 4.3% | 11.3% | 8.7% | 3.4% | - | 7.5% | 64.8% |
| 250kW/2h | 1.5% | 5.2% | 5.6% | 2.4% | 2.3% | 7.0% | 76.0% |
| 2500kW/2h | 0.7% | 2.5% | 2.0% | 1.3% | 1.0% | 5.0% | 87.5% |
Taking a 250kW/2h containerized BESS as an example, the batteries will account for approximately 76% of the total cost; the container, local controller, temperature control, fire protection, power distribution, and other related accessories (lighting, cables, etc.) will account for approximately 15.5%; and the PCS will account for approximately 7%. However, the grid-connected transformer is not included in the above system.
It can be seen that, from the perspective of hardware and manufacturing costs, as the capacity and power of energy storage systems continuously increase, the proportion of costs for the power conversion system (PCS) and other electrical and structural components will decrease accordingly, while the proportion of battery costs will continuously increase. Therefore, controlling battery costs will have a decisive impact on reducing the overall cost of battery energy storage systems (BESS).