What is energy storage battery?

Energy storage batteries, as the name implies, are battery systems used to store electrical energy. They are able to convert electrical energy into chemical energy, store the charge in the battery, and then release it when needed. Energy storage batteries are usually designed for long-term energy storage and charging and discharging, for example, they play an important role in grid dispatching, peak load reduction and power management. The key features of energy storage batteries are high capacity, long cycle life and stable performance.

Energy storage batteries are widely used in power grid energy storage, household energy storage, industrial and commercial energy storage, communication base stations and other fields. The design requirements of energy storage batteries are mainly optimized for energy density and long-term storage to meet the needs of large capacity and long-lasting energy storage. Since most energy storage devices do not need to be moved, energy storage lithium batteries do not have direct requirements for energy density; different energy storage scenarios have different requirements for power density; in terms of battery materials, attention should be paid to expansion rate, energy density, electrode material performance uniformity, etc., in order to pursue the long life and low cost of the entire energy storage equipment.

Power batteries are used in new energy passenger cars, commercial vehicles, special vehicles, engineering machinery equipment, ships, etc. Power batteries pay more attention to power density and short-term high power output to meet the needs of electric vehicles for rapid acceleration and long mileage. Compared with energy storage batteries, power batteries have higher requirements for energy density and power density. Furthermore, since power batteries are limited by the size and weight of the car and the acceleration at startup, power batteries have higher performance requirements than ordinary energy storage batteries.

The power battery pack is basically composed of the following five systems: battery module, battery management system, thermal management system, electrical system and structural system. The cost of the power battery system is composed of comprehensive costs such as battery cells, structural parts, BMS, box, auxiliary materials, and manufacturing costs. The battery cell accounts for about 80% of the cost, and the cost of the Pack (including structural parts, BMS, box, auxiliary materials, manufacturing costs, etc.) accounts for about 20% of the total battery pack cost.

The energy storage battery system is mainly composed of battery packs, battery management systems (BMS), energy management systems (EMS), energy storage converters (PCS) and other electrical equipment. In the cost structure of the energy storage system, the battery is the most important component of the energy storage system, accounting for 60% of the cost; by the energy storage inverter, accounting for 20%, the EMS (energy management system) cost accounts for 10%, the BMS (battery management system) cost accounts for 5%, and the others are 5%.

ACEY-APAL-ESS Lithium ion battery pack assembly line is mainly used to complete the sorting, welding, testing and assembly functions of square shell lithium battery modules for energy storge system. The line includes: manual loading, automatic code scanning, OCV testing, automatic NG discharge, battery cell cache, manual stacking and bundling, manual module handling into boxes, manual code scanning & labeling, polarity detection & terminal addressing, terminal laser cleaning, manual connection piece placement, laser welding, EOL testing, cantilever module transfer, manual pack assembly, hoisting off the line, pack tooling tray manual lifting car reflow assembly process.

The energy storage battery management system is similar to the power battery management system, but the power battery system is in high-speed electric vehicles, and has higher requirements for the power response speed and power characteristics of the battery, SOC estimation accuracy, and the number of state parameter calculations. Related adjustment functions also need to be implemented through BMS.

Power batteries and energy storage batteries have different requirements for service life. Energy storage batteries usually need to have a longer cycle life and can withstand thousands of charge and discharge cycles without significantly reducing performance.

Taking electric vehicles as an example, the theoretical life of a ternary lithium iron phosphate battery pack is 1,200 times. Based on the frequency of full charge and discharge once every three days, the life of a ternary lithium battery reaches ten years.

Energy storage batteries are charged and discharged more frequently than power batteries. Under the premise of the same 10-year lifespan, they have higher requirements for cycle life. If energy storage power stations and household energy storage are charged and discharged once a day, the cycle life of energy storage lithium batteries must be greater than 3,500 times. If the charge and discharge frequency is increased, the cycle life requirement is usually required to reach more than 5,000 times.

 05 Cost difference 

It is understood that energy storage lithium batteries also have power types, such as those that support a stable current discharge capacity of about 5C and are widely used in frequency modulation. Some companies will also reuse retired power batteries as energy storage batteries for household storage and mobile energy storage.

Acey New Energy specializes in providing one-stop solutions for semi-automatic/fully-automatic assembly lines of lithium battery packs used in ESS, UAV, E-Bike, E-Scooter, Power Tools, Two/Three Wheelers, Etc. In Addition, we provide a complete set of battery pack assembly equipment, such as Cell Grading Machine, Battery Sorting Machine, Insulation Paper Sticking Machine, CCD tester, Manual/Automatic Spot Welding Machine, BMS Tester, Battery Comprehensive Tester and Battery Pack Test System, etc.