I could not find anything conclusive, but Maukka tested them here and believes they could be VTC6. He measured about 3,000 mah. I dont know why Acebeam lists it as 3100mah.
If it is a VTC6, just keep in mind that it is rated at 15A continuous. It can do higher than that, just not continuously as it gets too hot. Acebeam puts 20A on the label as that is what the protection circuitry trips at.