Zinc-air batteries have been around and in use since the 1930s...

Zinc-air batteries have been around and in use since the 1930s (mainly as primary cells)
Zinc-air output a low voltage of around 1.35-1.4V compared to NMC Li-ion 3.7V and Imperium3's BM-LMP of 3.9v

The rechargeable versions (first developed and put to use in 1996) are physically large due to high internal resistance and have a risk of hydrogen explosion from zinc corrosion.

You want good ventilation with these due to the potential hydrogen gas output but also need to be careful to not use them in humid climates as this can flood the cathode and destroy its properties. Using them in hot dry climates can dry out the water in the electrolyte.

Energy density is better than Li-ion though and the raw materials are fairly cheap.

How many discharge/recharge cycles is the other important bit of info which seems unavailable for most companies producing rechargeable zinc-air batteries, including the company you linked.