Banana stores well at a temperature of

Banana stores well at a temperature of 13°C.
Keep them cool and protected from the light: Bananas should be stored at around 13°C, as they will ripen quicker if they are too warm.
Bananas grow in hot climates, so they are unused to the cold. If they're kept at a cold temperature in the fridge, the enzymes that enable them to ripen are inhibited. And as those enzymes become inactive, other enzymes operate more efficiently. Some cause cell damage, while others (browning enzymes) cause the skin to blacken.