For small energy storage power products, lithium battery packs below 2KWh will choose cylindrical lithium iron phosphate batteries. And if it is a medium and large energy storage power product, which is greater than 2KWh, it will choose to use a prismatic lithium iron phosphate battery.
Why do small energy storage power battery packs choose cylindrical lifepo4 batteries?
Cylindrical lifepo4 batteries include 18650, 26650, and 32650. These three markets have more batches and the most common ones. There are also some less commonly used cylindrical batteries such as 18500 and 22650.
Cylindrical lithium iron phosphate batteries include 18650, 26650, and 32650. These three models are more common in the market. There are also some less commonly used cylindrical batteries such as 18500 and 22650.
Benefit 1: It is easy to combine and the structure can be varied. Like the 18650 battery, the batch is the most, and the market is also the most common. Its size is very flexible. We can design according to the structural requirements, such as 4S8P battery packs. We can make a 4*8 arrangement or make it 16*2 arrangement makes the dimension very flexible.
Benefit 2: It can meet the needs of small-capacity battery packs. For example, lithium iron phosphate battery pack products require a 12.8V 2000mAh battery pack. The prismatic batteries are generally large-capacity, and there is no way to meet the requirements. At this time, you can only choose the 18650-3.2V-2000mAh battery cell of lithium iron phosphate. 4 series and 1 parallel can meet the demand.
Benefit 3: When the cylindrical battery pack is combined, the gap between the battery core and the battery core is large, and the heat dissipation is good. Cylindrical battery, coupled with the cell bracket, has a stable structure, large cell gap and better heat dissipation.
Why do medium and large energy storage power battery packs choose prismatic liffepo4 batteries?
Benefit 1: The prismatic battery has a large capacity, and when a large lifepo4 battery pack is combined, and the number of batteries cells used is less, and the consistency of battery pack will be better.
For example, 72V 100An lifepo4 battery pack, if you use 3.2V 100Ah prismatic lifepo4 battery cell, only 20S1P, 20pcs batteries are enough.If you use lifepo4 cylindrical battery 32650-6Ah batteries, you need 20S17P, and use 340pcs batteries. The consistency of the battery pack is also related to the number of cells. The more the number of cells, the worse the consistency and the worse the performance of the battery pack.
Benefit 2: The process of the battery pack is simple and the processing is convenient. Large lithium battery packs, using prismatic lifepo4 batteries cells, can use positive and negative locking stud nuts, or laser welding process, the process is simple and convenient.
However, if a cylindrical lifepo4 battery is used, it is still a method of spot welding nickel strips, which is complicated and inconvenient for processing. At present, there are also cylindrical batteries using aluminum wire welding technology, which has high cost and unsatisfactory results.