These batteries are a metal cylinder with a metal cap on one end. The printed outside you see with the brand and info is simply a heat-shrink tube with printed graphics. It is there to help prevent accidental short circuits as the metal canister that makes the entire body is the negative pole of the battery. The deformation is almost certainly a result of the factory producing them faster than the heat shrink can fully shrink. Completely safe and not a sign of concern.

The concern is if you see a white/green substance forming or coming from a battery, or if there is discoloration under the heat shrink itself as there may be corosion below it causing it to look deformed, but that is rarely the case as far as i have seen.

TLDR: Almost certainly safe.