Some AW may have been Panasonics - but Panasonic doesn't (at least officially and right now) offer an IMR battery at all - Panasonics usually have various proprietary chemistries tailored to the task. Most of them are considered "safer chemistry" hybrid cells. The current process for Panasonics is actually called "NNP", you can find info and data sheets here:
https://industrial.panasonic.com/www-cgi/jvcr21pz.cgi?E+BA+3+ACA4001+4++WW
The manufacturers don't use the same denominations internally that we use - for them the cells are made for a specific purpose (power tools, e-mobility, tooth brushes/razors, laptops). The AW IMR 1600, Samsung 20R, some other cells are specifically for power tools - our max 10A don't bother them. Panasonic ..CH, ..PD are made for e-mobility, 10A permanent is about as high as they can go, which is perfect for regulated mods.
Anything higher than, guessing here, maybe 2800 mAh today are laptop batteries for long, slow discharges, often rated at or below 6A.
The closer you bring a cell to it's maximum, the higher its internal loss will be, the warmer it will become, the more vdrop you get.