Examples of homemade bat repellents include moth balls, cinnamon, eucalyptus, aluminum foil, Mylar balloons and mirrors. Moth balls, cinnamon and eucalyptus all contain smells that bats do not like, while aluminum foil, Mylar balloons and mirrors scare bats away.
In general, a homemade bat repellent can be made from anything that has bright lights and loud sounds. Certain items with a strong smell also work well. Other techniques to get rid of bats include spraying water in their colony or having natural predators such as cats present in and around the home.
If these homemade remedies do not work, ultrasonic sound devices can be purchased to scare bats away with a sound that only they can hear, or an exterminator can be contacted to remove the bats. In many places, it is illegal to kill bats, so they must be either scared away or relocated.