Did you get your Keeppower cell(s) from Banggood? I just looked them up, and the Keeppower 18350 1200mAh that Banggood sells are protected, and are ~3mm longer than the other Keeppowers they had which were not protected (750mAh). I also checked Mountain Electronics and Li-Ion Wholesale. Neither of them had Keeppower 18350 cells. But the longest non-protected cells I found were the Windyfire 700mAh at Mountain. Those were 35.7mm long with a button top. Funny, the shortest cells I found were the same Windyfire, but with a flat top, at 34.9mm long. The ones I bought recently were actually Vapcell (I forgot, thought they were Efest), and those are 35mm. My Aspire cells are the same, 35mm long.

So, it seems you need to check whether your cells are protected. Non-protected cells should fit fine. I don’t know if protected cells are supposed to fit or not.

EDIT: Looks like I’m slow to the draw. :stuck_out_tongue: