Yes, if the 2015 MacBook Air is the 13-inch version, not the 11-inch model which has a different battery. The 13-inch MBA 2015 and 2017 use the same battery and they are interchangeable. You can also use the battery from older 13" MacBook Airs but keep in mind that the 2010 to 2012 models have a slightly lower capacity of 50 WHr versus 54 WHr of the 2013-2017 models.