I have a mid-2012 13" MBA (1466) and I'm at the stage where I either pump some money into upgrades (battery & 480GB SSD for approx 400) or look at getting a new MBA (1600) or MBP (1600+). I try to replace machines after 3 years but it doesn't look like I'll have the funds this year to replace. Currently my MBA battery is running at around 65% capacity and I seem to be only getting a couple of hours at a time. For instance yesterday I lost around 50% of my battery while watching less than half an hour of video. I could drive two hours to my nearest Apple Store and have them replace it or buy a genuine battery online and do it myself (which I'm very happy to do). The question I have..... Will a 2013 MBA battery work in a 2012 MBA? Looking at the specs they seem to be very small with the only worry being a 0.3v increase in the newer battery. 2012: 7.3v, 50.0Wh, 6700mAh 2013: 7.6v, 54.5Wh, 7150mAh I know it's only a 7% increase in capacity but it all helps. And if the 0.3v doesn't make a difference then it would make sense to go with the bigger battery.