You do understand the spec sheet for the cells lists the max charge and discharge rates? Not rates you "have to use" for them to work properly.
I sure do. There is however what is called a "commissioning" charge, which is what industrial users (which these cells were designed for, not the average consumer), which typically exceeds normal-use specifications before you put them into service.
This *completes* the formation process - in the case of LFP that does not mean plate etching as with lead-acid, but ensures that the active material is equally responsive across the entire surface. That is not done at the factory since that involves time and energy costs, which would raise your price.
If this is not done, you run the risk or forming "tracks" of highly-responsive material, and less-responsive areas, leading to "hot spots" when high-current is needed. DIY EV users can spot these and lack of commissioning charges.
Consumers, who typically run very low SUB-C applications, never realize that this is a problem, because it is hidden from them with the use of a sub-c project.
These are industrial cells sold to consumers. If you want to play with big cells, then that means you need bigger toys. (chargers and so forth). Most consumers however, NEVER take that into consideration, and pamper their cells into poor performers.
Strictly speaking, by not realizing you have never commisioned a battery properly so that the entire surface area is equally responsive, and by using a sub-c application where this is not immediately apparent, those more active areas get worked harder than the less-responsive areas. Hence less cycle-life.
