How to choose the right energy storage system?

Energy storage systems are essential in the process of energy transition. An energy storage system is an energy management system that matches renewable energy generation, such as solar and wind power, with the grid to improve grid stability in the event of grid instability.

Energy storage technology refers to the transfer of energy from one place to another through batteries, electrochemical devices, or other forms. Energy storage systems can provide backup power, peak shaving, optimize grid loads and provide power in emergency situations. Energy storage systems typically include batteries, supercapacitors, energy storage units, energy storage technologies and energy management systems.

Batteries

Batteries are the core component of an energy storage system, storing electrical energy and releasing it. Batteries are composed of positive and negative electrodes, electrolyte and diaphragm, and are usually categorized into lead-acid batteries, lithium-ion batteries, nickel-metal hydride batteries, zinc-air batteries and hydrogen fuel cells. According to the material and working principle, batteries can be categorized into lithium-ion batteries (lithium-ion batteries), fuel cells (fuel-air batteries), and hydrogen-oxygen hybrid batteries (hydrogen-air hybrid batteries).

Supercapacitor

Ultracapacitors are electrochemical devices between batteries and cells, and are often referred to as “supercapacitors”. Ultracapacitors have higher power density, longer cycle life, lower charge/discharge voltage, lower cost, and the ability to operate under extreme conditions. Supercapacitors are available in a number of different configurations, including bilayer (double layer capacitor), monolayer (single layer capacitor), and multilayer (multilayer capacitor). Ultracapacitors can provide power and energy during charging and discharging without generating any additional energy. Compared with other energy storage technologies, ultracapacitors have high energy density and are characterized by long cycle life, fast charging and high power density. Currently, ultracapacitors are widely used in energy storage systems.

Energy Storage Unit

The energy storage unit is the core component of the energy storage system, which provides energy storage function, converts the electrical energy generated by renewable energy generation into mechanical energy, and stores the energy through the energy storage equipment on the energy storage unit.

Energy storage units can be divided into two types: one is a battery system composed of batteries and supercapacitors, and the other is a battery system composed of rechargeable batteries and other energy storage devices. Different types of energy storage units have different operating principles and technical parameters, and therefore they are designed differently.

According to the energy storage units commonly used in the current market, they can be categorized into two types: fixed installation type and movable installation type.

Energy Storage Technologies

Energy storage technologies are usually categorized into electrochemical energy storage, mechanical energy storage and thermal energy storage.

Electrochemical energy storage technology refers to the use of electrochemical reaction principle will be converted from one form of energy into another form of technology, mainly including lithium-ion batteries, sodium-sulfur batteries, zinc-manganese batteries and so on.

Mechanical energy storage technology refers to the conversion of mechanical energy into electrical energy technology, mainly including pumped storage, compressed air energy storage, flywheel energy storage.

Thermal energy storage technology refers to the technology that utilizes thermal energy to absorb, store and release energy, mainly including low-temperature fuel cells, low-temperature waste heat boilers and so on.

Other types of energy storage technologies include flywheel energy storage + battery, etc.

Energy Management System

The energy management system of the energy storage system is mainly responsible for managing the status of the energy storage equipment, such as battery status, charging and discharging currents, etc., and at the same time monitoring the operation of the energy storage system to ensure that the energy storage equipment is in a safe and stable state during operation.

With the continuous promotion of energy transformation, energy storage system will play an increasingly important role. At present, energy storage technology continues to develop, and the cost of batteries is also decreasing, making the application of energy storage systems more and more widespread. Therefore, with the rapid development of the new energy industry, how to choose the right energy storage system is a problem that enterprises need to consider.