Since cells are common to all battery units, how do we guarantee that every cell in our pouch cell production run operates to the required performance standard or margin? The pouch cell sorting workflow that you’ll want to prepare, ahead of starting production, will include a number of checks that contribute to improving performance, addressing defects, and finally increasing the efficiency itself. Let’s take a deeper look at how to specifically design your pouch cell sorting workflow.
Pouch Cell Sorting
Like any battery cell, pouch cell sorting focuses on minimizing defects by eliminating bottlenecks and adding QA measures during production. It focuses on the operational side of the pouch cells which comprise battery packs.
Familiarize yourself with your process: pouch cell inspection is specific to detecting faults, like stress fractures, from manufacture or mechanical handling.
Design your quality control steps and incorporate elements that will enable you to review the process.
Note the different feedback stages for the pouch cell, including battery cell tagging and tracking, being seamless to eliminate stops.
When you’re drawn to help you streamline errors, check elements discreet to specific faults. For example, assess if the cell was tampered with. Did the pouch mis-lay against something? You’ll be stupefied with how minor a check is to handle.
Next in pouch cell sorting is testing capacity. You’ll want to discharge your cells under similar circumstances?, and these cells should be marked, redone with other tests or altogether scrapped. For high-accuracy capacity sorting, painstakingly designed equipment should be used. For this reason, battery testers with load simulation are the superior choice. At this stage you will use semi-automatic or automatic battery sorting machines, and this liberates operators and increases throughput.
Specialist equipment for testing voltage
Also a pouch cell voltage tester is a necessity, in order to make sure that each individual cell is within its own specific limits. Cells with voltage abnormalities may have internal connection problems, or they may be defective. Mark and sort out cells that are out of limits, and do not include them in the finished product.
To this end, many battery sorting machines are equipped with a voltage tester, in order to render the work a whole lot easier. The use of specialized sorting machines which computerize the work, and can thus draw up a ranking and sort on voltage air tightens the selection process, and users lessen the chances of repetition errors.
Testing Internal Resistance
Internal resistance in turn affects the battery cell in terms of efficiency and its life. If too high, then problems arise in terms of poor performance, heat generation and reducing the life of the battery. Internal resistance testing is done by applying small values of current to the battery and looking at the drop in voltage.
You should test for this important parameter, and to this end use IR tester to test the cell within your automated sorting machines.Sorting & classification
Once the cells have been tested for capacity, voltage and internal resistance they are ready to be sorted. Sorting is commonly based both on these parameters – (grouping cells of the same capacity together), and also voltage and resistance range.
Automatic pouch cell sorting machines will perform this classification so that the cells will be sorted according to performance. These machines for pouch cell sorting can also store results per cell, which can then also be traceable in terms of where the cell heads.
Packaging & FINAL inspection
Once the cells have been packaged they will then also have to be suitably packaged for transport / integration into a battery pack. A final inspection only to include cells termed fit for the purpose. This may involve further optical inspection or also automated checks for labels, packaging, safety, etc. Suitable grading/sorting may also be included.
For a blossoming of this section consider a complete solution that packages and inspects at the same time as sorting.
Designing the pouch cell sorting workflow
It’s necessary when you re designing this stage of equipment of your new workshop for sorting pouch cells to have certain considerations in mind. Some of those points are as follows:
Automation & Integration. The more you can do to sort the cells, the more efficient it will ultimately be.Automated Battery Sorting Machines
Automated battery sorting machines reduce the potential for human error, increase throughput, and improve consistency in sorting.
Accuracy and Precision
Every area of your testing and sorting system needs accurate test equipment, whether it’s capacity tests, voltage tests, internal resistance tests, and so on. A cell sorting machine that’s not accurate in its work threatens to drag down your entire production quality control metrics.
Flexibility for Different Cell Types
More pouch cell types and chemistries are appearing on the market; can you test and sort them all? Make sure that your sorting equipment is flexible enough to be able to cope with different cells.
Data Collection and Traceability
A mechanism for collecting and tracing the data from each cell’s test results can provide valuable insight into your production. You can use this data both for quality control, but also for trending and improving your equipment where need be.
Safety and Compliance
How does your sorting workflow integrate into other areas of your processes, and how does it integrate with either industry standard, or in-house; safety protocols. Pouch cells can cause safety risks if improperly dealt with, so safety measures should be integrated into your design.
Conclusion
Designing an effective pouch cell sorting workflow is more than dealing with separating defective cells from high quality, it’s designing a prompt, efficient and accurate system that builds accurate test equipment into the core of your sorting practices.
With the right equipment, you can save on all sorts of waste; from wasted cells to wasted testing. As more pouch cell types emerge and become commonplace, automated pouch cellular sorting systems will become mainstream for those producing electric vehicle batteries, consumer electronics, and other contact applications.
