Scarily tight aluminium USB power bank.

I normally buy my USB power banks online from China, but I saw this one in TK Maxx and bought it to take apart and see how easy it was to open and whether there was a decent battery inside.
It's VERY tight inside to say the least. The battery and the thin wire that runs up its side are a tight friction fit in the tube, and the length is absolutely on the limit for the 18650 style lithium cell and the PCB. It was quite scary to take apart and reassemble due to the existing factory damage to the heatshrink on the cell and the vicinity of the PCB to the side of the case that is almost certainly in electrical contact with the negative terminal of the battery.