Comparison of high-power energy storage devices for frequency regulation application (Performance, cost, size, and lifetime)

The penetration of renewable energy sources (RES) has caused some challenges for grid operation, including frequency variation, low power quality, and reliability issues. These challenges can be mitigated with the help of battery energy storage systems (BESS) which are characterized by long lifetime and high-power capability. Among the different types of high-power storage devices, lithium titanate oxide (LTO) batteries and lithium-ion capacitor (LIC) cells attract more attention. The performance behavior, the total cost of the battery system, and the system’s size are some other criteria for cell selection. This research compares the performance behavior of an LTO battery type for this application with two LIC type storage system at positive and negative temperatures and also considers the system size, cost, and lifetime of the BESS. The result proves that LICs are better candidates for low and high temperature applications in terms of energy efficiency and capacity drop. However, in terms of cost and size, the high-energy LTO cells are a better selection.