Can a Single Machine Sort Both 18650 and 21700 Cells?

As battery technology adapts, so does the demand for smart battery sorting machines. Among the most widely used of these cells in such applications as consumer electronics, electric vehicles (EVs) and storage are of course the old stalwart 18650 & 21700 cell. But with different size and different uses, we ask ourselves; can one sorting machine do all these cells?
18650 & 21700 Cells; What’s the difference. Before we ask our sorting machines what they can and can’t do, we’ve laid out the cells in question above;18650 Cells; The older cells come cylindrical and go into everything from laptops to power tools and EVs. Their name comes from the size; 18mm wide, by 65mm in diameter. They are a high density energy standard and have been around for many years.21700 Cells; They came later, bigger and built bigger; they are found 21mm wide, by 70mm long. The 21700 format contains much higher capacity and much higher energy density, hence is a popular format in the EV and high-power markets. In comparison to the 18650 cells, the latter are much smaller but whilst this really doesn’t matter to the machines that sort them, it does matter in terms ofBattery Sorting MachinesSorting out batteries is part of the important effort that goes into categorization and grading of cells by their required specifications (capacity, voltage, and so on).Hence the sorting machine is a necessary piece of kit if those batteries are to perform as required.
Sizing 18650 and 21700
With cells of the smaller size say 18650 and 21700, the size difference is significant and this height/length aspect needs factoring in any sorting machine. Battery sorting machines are typically set up with an aperture for one size cell to slide through. A machine set up for one of those large cells will not work with the other smaller one.
Another consideration is that of capacity and voltages. Subsequently a good sorting machine will be able to separate out the cells according to their differing parameters even if they are all from the same manufacturer. High-end sorting machines test for cell voltage too, again an important consideration with regard to performance.
Can They Do Both?
The answer lies in the design of the sorting system to be deployed.Certain more sophisticated battery sorting machines possess an element of flexibility, having adjustable components that allow them to cater to variously sized battery cells such as 18650s and 21700s.
Key Features of Multi Size Sorting Machines
Adjustable Feeders – By making provision of components that can dynamically adapt, the width height and length of the receptacle the cells settled into for being stacked and picked, it is possible to sort the cell of the 18650 variety or that of the less popular though at least longer 21700 without needing two completely different sorts of machine.
Grading and Testing – The better sorting machines will grade and test accurately and the sensors and software will also be construed capable of testing e.g. a 18650 over a 21700 cell and vice versa & likewise all those further complicated the more modified for size and a myriad of other cell characteristics. (e.g. capacity and internal resistance are two parameters of importance)
Versatility – The machine should be “best” as a generalist taking a practically any battery type of size and delivering an efficient degree of rating and sorting relative to this. Ellison Technologies talks about a smaller company who required sorting machinery that needed no other pieces of gear, but wait….these new machines do!
Multi channel – This is a fairly recent added-progression when we sometimes see “multi-channel” whereby the machine can simultaneously cope with the other larger or smaller “sizes” and types of batteries, conduct the requisite tests and ratings & sorting in an efficient “operation.”
ConclusionLong of the kind that could only sort a cell by rating it against itself, the old style sorting machine -designed for 18650- must have morphed into something far more versatile. Sure, with incrementally upgraded software and other of adjustable sort (e.g.dynamic),one sorting machine can indeed sort a 18650,then a 21700; and likewise all sized cells in between.