Prediction of energy storage battery development trend for the future

What is the difference between energy storage battery and power battery? Some people have likened it to “converter” and “generator”. According to different application scenarios, the former is mostly used in power systems, which requires low cost and long life; The latter mainly provides power for vehicles and pursues high energy density.

Although the production lines of the two can be shared, with the rapid development of the energy storage industry, the scale of the energy storage power station is often at the level of 100 megawatts or even gigawatts, and the customer’s appeal for customized and specialized energy storage batteries is soaring.

In the future, energy storage batteries will certainly open up their own independent development track, which is not only the need to reduce costs and increase efficiency, but also the requirement of safe development.

The development of energy storage battery towards large capacity is the trend of technology iteration

In an electrochemical energy storage system, the cost of batteries accounts for about 60%. In recent years, the scale of the energy storage industry has expanded rapidly, with the pressure of reducing costs. The energy storage industry has put forward an urgent demand for high economy of energy storage batteries.

In 2020, CATL will take the lead in introducing the 280Ah electric core with long cycle life, gradually replacing the original 50Ah-100Ah electric core and becoming the standard configuration for bidding or product procurement of energy storage projects. Mainstream battery manufacturers in the industry have followed up and intensively introduced 280Ah cells or even larger cells.

In May this year, Cornex released the “Cornex I” product, with a cell capacity of 280Ah and a single cell cycle life of more than 10000 times. In August, Hitium released the first 300Ah electric energy storage battery and large cylinder household energy storage battery.

In October, EVE Storage released a new generation of energy storage battery LF560K, further increasing the cell capacity to 560Ah. Battery manufacturers are speeding up competition on the track of high-capacity battery cells.

The special battery for energy storage has been ordered by large customers, and the market response is very warm. The development of energy storage battery to higher capacity is one of the trends of technology iteration.

Large capacity batteries can reduce the cost of energy storage system by reducing the cost of battery structural parts, reducing the number of system components, simplifying the production line process, reducing the number of equipment, reducing labor input, etc.

In this regard, the insiders believe that the development path of energy storage batteries is to reduce costs and increase efficiency through technological innovation and upgrading.

The use of small capacity batteries, with a large number of parallel connections, covers a large area for system installation, while the use of large capacity cells can effectively reduce the number of prefabricated cabins, and the cost per kilowatt hour also has a certain reduction, which can significantly improve the overall investment income of users.

The data shows that compared with the previous LF280K energy storage battery, using the LF560K battery can reduce the number of cells by 50%, reduce the number of battery pack parts by 47%, and improve the production efficiency by 30%.

Safety is the premise of energy storage battery research and development

The insiders believe that the current energy storage battery has entered a period of concentrated technological change. In addition to large capacity, high voltage and liquid cooling systems are attracting market attention.

At present, more and more lithium energy storage battery manufacturers in China have started production and research and development of special energy storage battery production lines. Battery companies, including EVE, Great Power, Hitium, REPT, Cornex, Envision AESC, have released special energy storage batteries to seize the development opportunities.

It is worth noting that the research and development of energy storage batteries must be based on safety, and the battery capacity is not always large. Too large will increase security risks. The increase of capacity will lead to the poor heat dissipation performance of the battery itself.

At the same time, battery expansion may cause battery cell bulge, which will lead to overcharge and thermal runaway, and it is difficult to cope with it. It is necessary to make a balanced design for battery thermal management.

Safety is the bottom line of energy storage industry development. At present, the energy storage industry is still in the early stage of development, and the technical standards and acceptance standards are not perfect enough. It is difficult for customers to identify various energy storage technologies and their products.

In this case, some companies without strength blindly run large capacity projects, which increases the security risks. Large capacity is not unlimited amplification. It is necessary to achieve the balance of large capacity, high safety and long cycle life. Battery energy storage is not a source of energy, but a transfer station with limited capacity.

The battery capacity is closely related to the installed capacity and application scenarios of the energy storage system/power station. For example, large storage systems are usually more suitable for matching large capacity cells, which can greatly improve the energy density of the energy storage system. This is the development trend of the large storage market, while small capacity batteries are sufficient for household energy storage.

Manufacturing capacity of energy storage battery still needs to be strengthened

This year, the demand for energy storage market is extremely strong, and the supply of 280Ah battery is in a tight situation. For manufacturers, whether they are building a special energy storage battery production line or upgrading the original power battery production line, a certain production expansion period is required.

It is understood that the production of energy storage battery mainly includes lamination and winding, with high degree of automation and production efficiency. However, the consistency of the 280Ah electric core produced by winding requires a manufacturing process much higher than that of the 50Ah-100Ah electric core.

Large capacity battery brings great challenges to the design and manufacturing capacity. The winding process is generally adopted for small electric cores, with high production efficiency, while the production line needs to be upgraded for large electric cores to reach the required technical parameters.

How to ensure the safety, efficiency and stability of electrochemical materials during the production process is also the key. These are the problems that need to be overcome for the current energy storage battery. It is a physical law that the production efficiency of large cells is lower than that of small cells. The large capacity battery has put forward new requirements for production equipment.

Taking the existing 280Ah intelligent production line of Hitium as an example, the R&D and manufacturing teams have carried out corresponding design and development on the process equipment of all assembly sections and test sections, and done a lot of work. In the future, to create a high-speed production line with higher capacity, practitioners need to continue to tackle technical problems.

In addition, the energy storage market has not yet reached the stage of large-scale development. In the first half of this year, the scale of new energy storage projects newly planned and under construction is close to 130 GWh, and the actual operation volume is less than 1.5 GWh.

The energy storage business model is not yet mature, and battery companies are also cautious in expanding production due to the impact of the rising prices of raw materials in the upstream.