Changes in the cooling method of the energy storage system: comprehensively transforming the theoretical life of lithium batteries into real life

　　With the increasing global demand for clean energy, energy storage systems have become a key link in ensuring the large-scale development of clean energy and the safe and economic operation of power grids. With the continuous introduction of favorable policies for the energy storage industry by various governments, energy storage has become an important means to solve the energy transformation.

　　The energy storage industry has entered a period of rapid development, and SES Power has also carried out research and development and layout in this field early. According to our experience, safety is the core issue of energy storage power stations, and thermal management is an important guarantee for energy storage safety!

　　Although the requirements of various international standards for thermal management systems are relatively vague, we can draw some inclinations from the self-requirements of some industry leaders; the wider application of large cells in energy storage systems leads us to put forward higher requirements.

　　Among the major mainstream technologies of thermal management, SES Power judges that by the second half of this year, the liquid cooling technology route will gradually surpass the air cooling route and occupy the mainstream in the market; from the perspective of the competitive landscape, the industry leaders with a huge market share will gradually dominate In the thermal management market, the industry will gradually form its own internal industry standards.

　　A: The penetration rate of the liquid cooling solution will increase

　　As more and more projects require energy storage for new clean energy power generation projects, such as photovoltaic power generation, wind power generation, etc., this greatly increases the market demand for energy storage. Battery thermal management is critical to the longevity and operational safety of batteries, especially lithium-ion batteries. At present, many companies have deployed thermal management products for energy storage systems. Most of them start from their own product technology, and both air-cooled and liquid-cooled technical routes are carried out simultaneously.

　　Large-scale projects require the capacity of lithium battery cells to be greater than 200Ah, and even require a single cell capacity of 280Ah, which puts forward higher requirements for thermal management systems. The first is the life of the cell, and the second is the consistency of the cell. These two links are very important and are the key points. If the thermal management system is planned reasonably, the risk of system safety can be greatly reduced.

　　The cooling methods of the temperature control system of the energy storage system mainly include air cooling, liquid cooling, heat pipe cooling, phase change cooling, etc. Among them, air cooling has the advantages of simple solution structure, flexible application, and low maintenance cost, but at the same time, due to the low specific heat capacity and low thermal conductivity of air, it is easy to generate dust accumulation, and air cooling is generally used in low-power scenarios. Liquid cooling is a thermal management of the system in the form of coolant, liquid flow channels, and liquid coolers. Its advantages are good cooling effect, fast response speed, and easy modular control management. It can be used in different scenarios. Longer service life. Of course, liquid cooling systems are more complex and expensive.

　　At present, the top technology manufacturers in the market, such as CATL, BYD, EVE Lithium Energy, and Sunshine Energy, are promoting liquid cooling as a key product this year. Judging from the current trends in the bidding of energy storage projects in various countries, almost all of them have more and more stringent requirements for battery life. Therefore, 100% of the solutions proposed by these industry leaders are liquid-cooled, and the air-cooled solutions have been completely abandoned by them. However, in some projects that require relatively low battery life and are particularly concerned about cost, these companies will still use air-cooled solutions for cost control.

　　SES Power believes that in the future, with the improvement of energy storage energy and charging and discharging rate, the proportion of liquid cooling will gradually increase. In the second half of this year, the liquid cooling technology route will gradually surpass the air cooling route and occupy the mainstream in the market. From the current point of view, the market share of liquid cooling and air cooling is expected to be about 6:4.

　　B: Industry leaders will dominate the thermal management market

　　The main energy storage element of many energy storage systems is the battery, especially the lithium iron phosphate battery pack. The liquid cooling system of the battery pack mainly includes liquid cooling controllers, pipelines, quick connectors and other components. Generally, downstream energy storage system integrators purchase components and perform final assembly.

　　Judging from the current industry development trend, battery manufacturers will be the biggest beneficiaries of liquid cooling systems because they have a deeper understanding of batteries. For example, like the CATL, because its battery life is relatively long, it can be done nearly 10,000 times. Combined with its own liquid cooling technology, and the consistency and quality of the battery are relatively good, the life of the energy storage system can be achieved. Close to 8000 times, which is almost the full theoretical life of all batteries.

　　Such a situation is very beneficial to improve the long-term economics of the energy storage system, because the energy storage system is based on the real end life as the basis for calculating the cost.

　　SES Power believes that the ecology of the energy storage system is relatively clear. It should be said that the entire energy storage field is dominated by integrators, and integrators cut in from several fields. Weiwei, they supply the core components with the battery as the core, and carry out the overall design of the battery system.

　　Others cut into the field of battery energy storage systems by providing core components, such as Sungrow and Huawei. In the end, these companies provide terminal brands and products.

　　Therefore, we hardly see a company specializing in thermal management of battery systems in the market. It can be said that the integrators themselves conduct a leading design of the entire system, and then go down to find suppliers of related components.

　　C: Technology will bring profits

　　One thing we cannot ignore is that although the liquid cooling system will increase the cost, it will ultimately increase the overall gross profit margin of the energy storage system. The reason is simple, advanced technology will always bring good gross margin. Regarding the profit composition of each link of energy storage, if you look at the gross profit rate, the current BMS system is the highest, and the gross profit rate can be about 30-40%. However, from the perspective of cost structure, the proportion of cells in the energy storage system must be the largest. Choosing the correct cooling system will improve the competitiveness of the cells, which will ultimately be reflected in the price.

　　SES Power is a professional supplier with nearly 20 years of experience in the lithium battery industry. Our energy storage products, such as 12V100Ah, 12V200Ah, 24V100Ah, 24V200Ah, 36V100Ah, 48V50Ah, 48V100Ah using square aluminum-shell lithium batteries, are suitable for home energy storage. System HESS (3KW inverter output), in many cases, a temperature control system will be added according to the actual needs of customers. Of course, there is a cooling system, but also a heating system. However, in some cases, the temperature control system cannot be used. Our customized lithium-ion battery can be used in an environment of -60 degrees and -40 degrees Celsius.

　　To put it simply, an advanced temperature control system will make better use of the battery, ultimately forming a win-win for both the manufacturer and the user.