Not really. The upper charge limit of 4.2v is arbitrary. It’s a compromise between capacity and cycle life. If you charge to 4.1v (which many do), you’ll get about twice the cycles but lose 10% capacity. If you charge to 4.3v, you’ll lose half your cycles but gain 10% capacity. Depending on whether you charge to 4.1v or 4.2v or 4.3v, changes the effective capacity of the battery.

Just because 4.2v is normally the voltage chosen, doesn’t necessarily make it the right one.

I get what you’re saying, but I also understand what his point was too. You can view it either way.

As for Ultrafire 12000mAh 18650 cells, well… I don’t know quite how they manage that.