Preheat the air fryer to 212 degrees Fahrenheit or 100 degrees Celsius while preparing the bananas. Next, slice the bananas into thin slices.
In a small bowl, coat the banana slices with lemon juice and sprinkle lightly with salt. Spray the banana slices with oil. Flip the slices and repeat.
Place the banana slices in a single layer on the base of an air fryer basket. Place the basket into the air fryer and cook the air fryer banana chips for 40 minutes.
Check halfway through the cooking time and loosen the bananas from the base of the basket if needed. Continue to cook.
Finally, remove the chips from the air fryer and place on a cooling rack. Repeat the cooking process with the rest of the bananas slices.