The various energy storage devices are Fuel Cells, Rechargeable Batteries, PV Solar Cells, Hydrogen Storage Devices etc. In this paper, the efficiency and shortcoming of various energy storage devices are discussed. In fuel cells, electrical energy is generated from chemical energy stored in the fuel.
In hydrogen and other hydrocarbon fuels has higher storage of chemical energy as compared with common battery materials (1). (Figure 1) shows the different reactions and processes that happens in various fuel cells (2). Fuel cells are electrochemical devices that convert chemical energy into electrical energy through a controlled redox reaction.
It is important to compare the capacity, storage and discharge times, maximum number of cycles, energy density, and efficiency of each type of energy storage system while choosing for implementation of these technologies. SHS and LHS have the lowest energy storage capacities, while PHES has the largest.
In Photovoltaic solar cells, there is direct conversion of solar energy into electric energy. This energy is transferred directly to energy clients for usage, without being stored. However, in the rechargeable batteries like inverters covert electric energy into the chemical energy that can be stored for further use.
Large-scale battery storage facilities are increasingly being used as a solution to the problem of energy storage. The Internet of Things (IoT)-connected digitalized battery storage solutions are able to store and dynamically distribute energy as needed, either locally or from a centralized distribution hub.
Electrochemical batteries, such as lithium-ion (Li +), sodium‑sulfur (NaS), vanadium-redox flow (VRF), and lead-acid (PbA) batteries, are commonly used for all ESS services [, , , , ]. Fig. 3. Classification of energy storage system based on energy stored in reservoir. 2.1. Mechanical energy storage (MES) system