m15 R5, clarifying question on secondary SSD?

I know my m15 R5 has a single 512GB SSD drive (BC711 NVMe SK Hynix 512 GB) which I believe translates to the M.2 2230 drive in the docs. The docs indicate that a second drive can be a M.2 2280 model up to 2 TB.   

What that tells me is that I could add a second drive as long as it was an M.2 2280, and indeed Crucial indicates suggests: Crucial P5 Plus 2TB PCIe M.2 2280SS Gaming SSD | CT2000P5PSSD8 | Crucial.com. Is this correct?

Do I need some sort of heat shield for it? I see that mentioned a lot.

I just need more disk space to move less demanding games to the secondary drive freeing up space on the main drive for the more demanding ones.  

Thanks, and apologies for asking this yet one more time, but it seemed the other questions were more geared toward replacing the main drive, raid, et al.