Safety and economic cycle life of 280AH energy storage cells

Technology Sharing | A&S POWER | Aug 22, 2023

The external publicity of battery cell factories is generally an economic cycle life of 6,000, 8,000, and 12,000 times. This is the result of derivation in a specific experimental environment and data model. When the battery core is made into a battery pack through PACK, and the battery pack is used in an energy storage system, its economic cycle life is an issue that the industry is reluctant to mention both subjectively and objectively; because it will shake everyone's understanding of the energy storage business. Pattern confidence.


The profit models of current commercial energy storage systems, centralized or distributed, are all based on the number of cycles and safe operation. We will take the mainstream product of the target energy storage system as an example, the lithium iron phosphate 280AH square aluminum shell battery cell. Discussion:

 

1. Safety;

In the second half of 2022, Ouyang Minggao, an academician of the Chinese Academy of Sciences, warned that the explosion index of lithium iron phosphate in large-capacity batteries is twice that of ternary materials; and called on the industry to use 280AH batteries as the ceiling for large batteries and not to limit the capacity. Go big.


2. Economic cycle life;

The economic cycle life of 280AH battery cells reaches 6,000 times and exceeds 6,000 times. Each battery cell manufacturer has set prerequisites;

A Operating temperature, 25°C±2°C

B Initial clamping force 300KGF wrapped battery core

C charge and discharge depth, 80-90%

D charge and discharge rate 0.2C-0.5C

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The remaining capacity after 6,000 cycles is 70-80%. It depends on the product specifications of each manufacturer. As for those whose remaining capacity is about 60% after 8,000 cycles and exceeds 10,000 cycles, it is meaningless to determine the remaining capacity. Yes, this is just a gimmick promoted by the manufacturer;


The number of cycles of a single battery cell is not particularly significant for the number of cycles of an energy storage power station; the single battery core can be charged and discharged as part of the energy storage cabinet after being PACKed into a battery pack;


The three indicators of voltage, capacity, and internal resistance are the key indicators for cell assembly.


280AH was first introduced to the market by CATL in 2020. No more than 3 battery core factories will be able to mass-produce it in 2021. It will become the mainstream of energy storage power station applications in 2022, and a large amount of new production capacity will be invested in 2023;


280AH square aluminum-cased batteries will be put into large-scale use in 2021-2022. If we assume that the economic cycle life of 3,000 times holds true, after-sales incidents will occur after the first batch of 280 batteries are installed around 2025. The situation of sharp increase, everything needs to be verified by time.