I put a new battery in my 2011 11" MacBook Air. I love the laptop more than I minded the frustration. It will probably be easier for you.
I come from the time where we carried spare laptop batteries with us, and they were instantly swappable. I'd press a small button on the battery to light up some green LEDs to see how much juice was left in a spare. Those days are gone. We have now entered a dark age where batteries are sealed behind obscure pentalobe screws. After 7 years my treasured 11" Air was unable to hold a charge for longer than 75 minutes or so. I was fucked and going to have to open that case.
I love that little 11" laptop. It is the device I love to carry for creative writing. Small enough to not be a bother, functional computer enough to do anything I need in a pinch, and a screen a keyboard perfect for getting a first draft out. I did not want to lose this laptop, but the short battery life was killing me. Most of the coffee shops and places I like to work no longer want to offer power outlets to folks drinking one cup of black coffee for 2 hours.
I tried cycling the battery to restore some lost capacity. It did not help. I looked at the iPad Pro with a keyboard. I even looked at the Surface Pro. Then I researched batteries and the replacement looked like it should be no problem.
Ha. Ha. Ha.
I searched the internet's latest iteration of forums, Reddit and Youtube, for info on folks who'd replaced this model's battery. I read a lot of Amazon reviews. The size of the replacement battery was supposedly a problem in varying degrees with all models, even Apple sourced batteries. The Temark I chose seemed to have a high probability of going in without a problem.
https://www.youtube.com/watch?v=ejwRqM3fpVk
I used the included screwdrivers to remove the tiny, cruelly chosen screws. I kept the ones from the backplate separate from the battery screws, even tho they are different colors and sizes. When the backplate came off I saw that my battery had broken around one of the screws, damage from an apparent fall. I'd dented the case a bit too -- but the laptop never showed an issue. There were splintered bits of battery plastic all over. When I removed the battery, I noticed a thin metal bar had come loose in the area of the trackpad. It had been held in place by the battery pressure, I guessed, and needed replacement.
I looked at images of trackpads for my model Air and saw that the bar appeared to sit across the bottom of the trackpad, in-between it and the battery. I felt some residual sticky adhesive where it appeared to go, and the bar stuck right back there. I put everything back together, feeling like I was going to have to take all those screws out again, and should have tried powering up before I had screwed them all in.
The laptop turned right on.
The sign-in screen came up.
The battery showed about a 60% charge. I plugged it in and it started to charge right up.
I moved the pointer to my name/icon on the sign in screen and clicked.
No click.
Pointer will frantically move around the screen. No click.
Tapping at the very top gets me mouse click. I can login. Laptop is fine. Trackpad is not working. I realize it must be that damn bar, and that the adhesive hadn't held.
Power it all down.
Open it back up.
Re-affix the bar with glue stick.
One day later: repeat with electrical tape.
Everything works perfectly here, now. No, really. No problems. When I am done working on the blog this am, I'll take my Air to a coffee shop and work on a short story. It now gets 4-5 hrs of power. More than when it was new.
For $70 and maybe 2 hours of frustration I have a small-sized laptop I like a lot more than any of the new light-computer solutions out there.
It was actually very easy, my old laptop was just beat to hell.