Trends in Li-ion battery for energy storage.

According to the data, global energy storage battery shipments are expected to reach 120 GWh in 2022, and by 2025, global energy storage battery shipments will exceed 600 GWh. With the development of new energy sources, power storage is gradually becoming an important pillar of new power systems.

Although the current production line of energy storage batteries is basically almost common with the production line of power batteries, energy storage batteries and power batteries actually have essential differences. Power end products are new consumer products, more concerned about the experience. Energy storage, on the other hand, has the characteristics of new infrastructure and is more concerned with return on investment, payback period, cost of electricity, whole life cycle investment cost, etc.

As large-scale energy storage involves power grid connection, its demand for batteries is more complex than other scenarios. In order to better match the characteristics of power storage, more and more battery companies have started to develop matching battery products specifically for the needs of power storage. A unified consensus is forming in the industry: the independence of the market and the differentiation of application scenarios mean that energy storage batteries will be a new field with independent industry standards, independent technology paths, independent product layouts and completely independent industrial ecology.

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Based on this, energy storage batteries are moving towards exclusive and specialized product design, process selection and manufacturing paths with lower cost, longer cycle life and higher safety.

Power storage is a new infrastructure industry that values whole life costs.

Cost is an important parameter in determining the scale of energy storage technology application and industry development. The whole life cycle cost of electric energy storage includes installation cost and operation cost. The installation cost mainly includes energy storage system cost, power conversion cost and civil construction cost, while the operation cost includes operation and maintenance cost, recovery residual value and other additional costs.

The current consideration of batteries for power storage is mainly measured by brand, cost and performance. Power storage projects are still focused on the initial investment cost in the short term, and the trend in the medium to long term will be to look more at the whole life cycle cost.

Energy storage battery is the key to electrochemical energy storage system, the reduction of battery cost can directly bring the reduction of the first investment cost, shorten the payback period and improve the return on investment, while the increase of life can bring the energy storage system in the whole life cycle of the electricity cost reduction. The breakthrough of battery technology in cost is the key to the whole electric energy storage industry.

On the one hand, energy storage battery cycle life and other improvements, can greatly cut the whole life cycle cost. On the other hand, the improvement of battery performance can greatly improve the total discharge of the energy storage system, which is also an important means of empowerment for the energy storage system.

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At this stage, lithium iron phosphate batteries are mainly standardized mode of “high-speed factory” production, to achieve high safety and long life requirements. At present, the mainstream system of the industry is concentrated in the system of L80/100/125/170/200 and so on, that is, to ensure the distribution of different cell capacities by adjusting the height of the battery cell under the condition of certain length and width, so as to achieve the purpose of optimal production.

From the recent market performance, the latest generation of energy storage battery cells from well-known battery companies are long-cycle high-capacity models, mainstream power storage large battery cell capacity 280Ah has occupied more than half. (For more information about 280ah battery cell, please refer to here.) The trend of upgrading energy storage battery cells to high-capacity direction is obvious.

The advantages of large capacity battery cells in power storage applications are obvious: 1) it is easier to obtain high volumetric energy density with large capacity battery cells; 2) the use of components at the pack end is reduced, which is conducive to cost reduction; 3) it is easier to obtain high capacity with large capacity battery cells; 4) safety is improved; 5) the assembly process in the integration field is simplified.

More and more people in the industry judge that high-capacity batteries will be the mainstream development direction of power storage.

And such a judgment is mainly considered from the user economy. Energy storage configuration capacity gradually developed from a few MWh to several hundred MWh or GWh, system voltage also increased from 1000V to 1500V, the voltage is determined by the number of strings of batteries; system power is realized through the parallel connection of multiple prefabricated warehouse power.

Industry analysis, if a small battery, such as 100Ah, prefabricated warehouse power less, the number of parallel system will be more, covers an area of large, the overall investment will be large, then the battery capacity to 280 or 300AH, can effectively reduce the number of prefabricated cabin, and the cost compared to the small capacity there is a drop, the overall investment and revenue will be significantly improved.

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According to the current common 40 feet 2.5MWh air-cooled energy storage container in the market, it takes about 6510pcs battery cells if using 120ah, and about 2790pcs batteries if using 280Ah.The number of parallel connection can be reduced by more than half. It can be seen that the high-capacity battery cells have almost become the consensus of the power storage industry.

But how much is the limit, the industry does not have a uniform judgment on this. In the current technological development, the battery capacity is not the larger the better, the main reason is that the battery to do large also faces three major challenges: 1. Specific performance is the pole piece design becomes larger, the shell becomes larger, then the rate of excellence and efficiency will be reduced; 2. Overcharging and thermal runaway is more difficult to deal with; 3. From the perspective of the system, the battery is bigger to reduce the number of components, but the over current capability of the electrical connection is an important challenge.

For power storage, make a large capacity battery, not only from the cost aspect to be considered, but also from the safety of the system and other comprehensive analysis.

On the power storage battery towards proprietary, the industry has had similar calls before; and nowadays, power storage is often invested in GWh projects, and the demand for specialized power storage batteries is even stronger.

The call for proprietary batteries for power storage is actually a call for manufacturing processes, cycle life, low cost and high safety that are more suitable for the characteristics of power storage.

Therefore, future energy storage battery manufacturers should start from how to improve the whole life cycle performance and reduce the whole life cycle cost of the battery. The energy storage field needs more independent technologies and processes to support and achieve better whole life performance and lower whole life costs.


Post time: Dec-19-2023