What’s the Recommended Sorting Speed for Pouch Cells?

When it comes to battery production, particularly with pouch cells, the sorting speed is of utmost importance to ensure production efficacy and quality. Pouch cells are one of the most popular form factors of battery cell from electric vehicles (EVs) to solar power storage systems, and ensuring they are accurately sorted is of paramount importance from a performance, safety and lifetime perspective. Here we discuss the recommended sorting speed for pouch cells and what affects them.
Sorting pouch cells
Unlike cylindrical or prismatic cells, pouch cells have a more flexible flat structure that must be handled delicately. Sorting refers to the act of categorising the battery cell according to capacity, voltage or internal resistance, and ensuring that only similar cells are used together in the same battery pack – otherwise they may have differing performances and life. Battery sorting machines are designed specifically for the purpose, as well as making sorting quicker and more accurate, the actual sorting speed is an important parameter that must be carefully considered.
Cell size and design – pouch cells are anyway available in many sizes, and smaller cells may necessitate a lower sorting speed to ensure that each cell is properly captured and classified. Larger pouch cells may be able to cope with higher, faster sorting speeds.Sorting Machine Type
The type of sorting machine used plays a significant part in sorting speed. Fully automatic sorting machines are usually capable of higher speeds than manual or semi-automatic machines, but automatic machines do not sort correct if not properly set, and may break or even destroy cells at higher speeds.
Measurement Accuracy
To be blunt, speed in sorting should never be sought at the sacrifice of accuracy. The more delicate the required measurement (voltage, capacity, internal resistance, etc.) the more slowly such a sorting machines may be required to work, and in that case the retesting of the cells will be more thorough, and of more use in mastering designs, the result of which will be better parts being selected. The cell which does not meet the specification is relegated to another use altogether rather than sold.
The cell is of variable quality within the pouch, being of varying internal resistance and/or capacity.
In such cases the need for accurate sorting may require slower sorting speeds.
The cell may be liable to defects, thus necessitating the soriting of the cell more slowly so that there is less danger of damaging it or the sorting apparatus.
Recommended Sorting Speed
Pouchcells can conveniently be sorted at the rate of 100 to 500 cells per minute.But what is optimal? It really depends on what materials are being sorted and how large or small the cells are. For mass produced batteries, manufacturers may want higher speeds to match production speed, but should still be cautious.
Low-Speed Sorting (100-200 cells/min): Most suitable for high-end batteries or complex storage applications. Slower for more accurate sorting, especially for those cells with a small difference between them.
Medium-Speed Sorting (200-350 cells/min): This is a good mix of the two. Used in most commercial batteries, they need some accuracy to get through them in a decent time but don’t need to sort with extreme precision.
High-Speed Sorting (350-500 cells/min): For mass produced cells that are pretty uniform, you can afford to jiggle through them at this sort of speed. Used in small products which need a battery to do a job and are unlikely to notice the minor differences the initially pass on, these cells have much less demand for accuracy.
You’ll want to. Your sorting machine will need to be regularly checked and set up to match its demands. Even top end gear will begin to faulter over time and your cells will start to quarrel with each other.
We recommend a sort speed of roughly between 200 and 350 per minute for most applications, the high end of that speed being for the better composition cells, while the other for storage of poorer cells.