Battery drains during sleep mode

I too have this issue on my MBA. Mine is late 2012 but this has been going on for about 1 ½ years. if you click on the battery icon on the tool bar check to see if your battery says it needs servicing. Bring it in to an apple store and have them put in a new battery for you. Also on the older macs OS X 10.10.3 has some effects on the battery right after update. Try shutting down for a night resetting your PRAM.

Here’s how to reset your PRAM:

1. Shut down your machine. Yes, all the way down, not sleep or logging out.
2. Press the power button and then press command-option-p-r. You have to make sure you get those keys pressed before the gray screen comes up or it won’t work.
3. Hold those keys down until your Mac reboots again and you here the startup chime.
4. Let go of the keys and let your Mac reboot normally.

Good luck!

Probably your Computer isn;t sleeping.... Check it once more....

System preferences > Energy saver > Under Battery and Power adapter tabs do this.....

Hope this helps......