Why Does Lithium Battery Performance Vary Before Sorting?

Lithium-ion batteries power everything from laptops to cell phones; they’re also at the forefront of powering the future of transportation, renewable energy storage, and everything in between. But before batteries roll off the line to power these applications, the performance of each individual cell within a battery can vary significantly. Battery performance discrepancies within individual cells are often thought to arise from the sorting process that sculpts the battery into optimum shape for battery life and the efficient operation of the product as a whole.Why Does Lithium Battery Performance Vary Before Sorting?Optimising battery performance and ensuring a faithful replication of battery life in any cell takes a lot of hard work from a sorting machine—but are there reasons for discrepancies in lithium battery performance even before this step? The answers lies in two areas.1. Variability in ManufacturingThe performance of a lithium battery cell is often hedge against the risk of slight variances during the manufacturing process. Manufacturing battery facilities attempt to control these factors, and if the average results are intended on paper, discrepancies in the performance of individual cells can still arise. Slight differences in supplier of electrode material or building of cells, for instance, or simply variations in temperature, pressure, or even the consistency of the electrolyte.2. State of Charge (SOC) DifferencesNot dissimilar to the aspect of careful management through intimately affording considerable care and delivery, batteries can all too easily leave the line with differing levels of change. Thus far, some may have carried a higher state of charge (SOC) than others. Stepping back, batteries with cogent lower level SOC to lead to initial performance differences.Sorting machines that determine the SOC (State of Charge) characteristics of batteries load-matched them into packs with only those of similar SOC, making everything else equal and increasing battery pack consistency.
3) Internal Resistance Variation
Variation in internal resistance affects how much power a battery pack can deliver. Resistance connects everything up but the batteries! Hotter cells don’t last long and cause everything around them to overheat. These may be segregated or sorted on-resistance added to the pack to insure only high-performing cells are used for critical applications.
4) Age and Cycle History
Batteries that have aged for different lengths of time (how long batteries “rest & age” affects their performance even if they never left the factory), and number of cycles they have been through as opposed to cycled, vary widely in their performance characteristics. Sorting processes that can assess cycle-history or the “wear level” of nonactivated cells can aid in selection of the best cells for your application.
5) Temperature Sensitivity
Temperature has always played a key role in battery making. If lithiums get too hot, they can even become impotent when stored for a long time.Cold may yield the result ‘higher’, whilst hot might cause the battery to suffer degradation of the electrolyte. This leads to the requirement of cells to be separated, since those that are capable of bearing the higher temp simply are not capable of meeting the demand of hot applications.
Sorting machines can undertake such checks to ‘sort’ out the cells that are not able to meet the requirements due to their temperature dependency.
6. Battery Chemistry Differences
Strange as it might seem, not all lithium batteries are the same—even if they look very similar! There are many types of lithium chemistries (Lithium Cobalt Oxide (LCO), Lithium Iron Phosphate (LFP), Lithium Manganese Oxide (LMO)), yah, etc. Inconsistencies with kr2 batteries within a batch can lead to performance variance. Advanced testing methods_____ Such as impedance spectroscopy, or voltage measurement itself can be used by the sorters to identify & sort cells based on chemical type.
7. Performance Optimization by Sorting
Logically, by sorting batteries according to how they ‘perform’ (e.g. state of charge, internal resistance, chemical make up etc), the overall sucker performance across the entire batt pack can be improved. This helps avoid poor matching for critical applications & reduces the risk of overheating or putting excessive stress onto a battery that might not be built for the task at hand.
The obvious other aspect of this is when we sort batteries before assembly, to endeavor to unite cells that appear to act similarly together, improving the overall sucker performance of the assembly.
Getting the right battery sort machine for your business (18650 battery sort machine, 21700 lithium battery sorting machine, prismatic battery sort machine, etc) in place has to be a huge consideration for firms looking to optimize the gain to be made on lithium batteries.