The main structure of the battery energy storage system

Electricity is a necessary living facility in the twenty-first world. It is no exaggeration to say that all our production and life will enter a paralyzed mode without electricity. Therefore, electricity plays a pivotal role in human production and life!

Electricity is often in short supply, so battery energy storage technology is also essential. What are battery energy storage technology, its role, and its structure? With this series of questions, let's consult HOPPT BATTERY again to see how they view this issue!

Battery energy storage technology is inseparable from the energy development industry. Battery energy storage technology can solve the problem of day and night power peak-to-valley difference, achieve stable output, peak frequency regulation, and reserve capacity, and then meet the needs of new energy power generation. , the demand for safe access to the power grid, etc., can also reduce the phenomenon of abandoned wind, abandoned light, and so on.

The composition structure of battery energy storage technology:

The energy storage system consists of battery, electrical components, mechanical support, heating and cooling system (thermal management system), bidirectional energy storage converter (PCS), energy management system (EMS), and battery management system (BMS). The batteries are arranged, connected, and assembled into a battery module and then fixed and assembled into the cabinet together with other components to form a battery cabinet. Below we introduce the essential parts.

Battery

The energy type battery used in the energy storage system is different from the power type battery. Taking professional athletes as an example, power batteries are like sprinters. They have good explosive power and can release high power quickly. The energy-type battery is more like a marathon runner, with high energy density, and can provide longer use time on a single charge.

Another feature of energy-based batteries is long life, which is very important for energy storage systems. Eliminating the difference between day and night peaks and valleys is the energy storage system's main application scenario, and the product's use time directly affects the projected revenue.

thermal management

If the battery is likened to the body of the energy storage system, then the thermal management system is the "clothing" of the energy storage system. Like people, batteries also need to be comfortable (23~25℃) to exert higher work efficiency. If the battery operating temperature exceeds 50°C, the battery life will decline rapidly. When the temperature is lower than -10°C, the battery will enter the "hibernation" mode and cannot work usually.

It can be seen from the different performance of the battery in the face of high temperature and low temperature that the life and safety of the energy storage system in the high-temperature state will be significantly affected. In contrast, the energy storage system in the low-temperature state will ultimately strike. The function of thermal management is to give the energy storage system a comfortable temperature according to the ambient temperature. So that the whole system can "extend the lifespan."

battery management system

The battery management system can be regarded as the commander of the battery system. It is the link between the battery and the user, mainly to improve the utilization rate of the storm and prevent the battery from being overcharged and over-discharged.

When two people stand in front of us, we can quickly tell who is taller and fatter. But when thousands of people are lined up in front of them, the job becomes challenging. And dealing with this tricky thing is the job of the BMS. Parameters such as "height, short, fat and thin" correspond to the energy storage system, voltage, current, and temperature data. According to the complex algorithm, It can infer the system's SOC (state of charge), the start and stop of the thermal management system, the system insulation detection, and the balance between the batteries.

BMS should take safety as the original design intention, follow the principle of "prevention first, control guarantee," and systematically solve the safety management and control of energy storage battery system.

Bidirectional Energy Storage Converter (PCS)

Energy storage converters are very common in daily life. The one shown in the picture is a one-way PCS.

The function of the mobile phone charger is to convert the 220V alternating current in the household socket into the 5V~10V direct current required by the battery in the mobile phone. This is consistent with how the energy storage system converts the alternating current to the direct current needed by the stack during charging.

The PCS in the energy storage system can be understood as an oversized charger, but the difference from the mobile phone charger is that it is bidirectional. The bidirectional PCS acts as a bridge between the battery stack and the grid. On the one hand, it converts the AC power at the grid end into DC power to charge the battery stack, and on the other hand, it converts the DC power from the battery stack into AC power and feeds it back to the grid.

energy management system

A distributed energy researcher once said that "a good solution comes from top-level design, and a good system comes from EMS," which shows the importance of EMS in energy storage systems.

The existence of the energy management system is to summarize the information of each subsystem in the energy storage system, comprehensively control the operation of the entire system, and make relevant decisions to ensure the safe operation of the system. The EMS will upload the data to the cloud and provide operational tools for the operator's background managers. At the same time, EMS is also responsible for direct interaction with users. The user's operation and maintenance personnel can view the operation of the energy storage system in real-time through the EMS to implement supervision.

The above is the introduction to electric energy storage technology made by HOPPT BATTERY for everyone. For more information on battery energy storage technology, please pay attention to HOPPT BATTERY to learn more!