Battery not working at 100% charge

Where would I find this driver?

@bitflip @cacciatore98762 - No drivers here! Just like a flashlight you just slide in the new batteries.

But it would be helpful to to get a better view of things, install this gem of an app! CoconutBattery take a snapshot of the apps main window and post it here for us to see Adding images to an existing question

Make sure you have the MagSafe plugged in and give it a few minutes before you take the snapshot.

Well, considering that this replacement battery is an iFixit battery for your model of laptop, it is possible that you need to install, reinstall, upgrade, or repair the battery driver that is hopefully installed on your Macbook, so that the replacement battery can do what it is suppose to. After doing a little bit searching on the Internet,m I cannot find an exact driver for your laptop model that is a genuine driver for this battery. I would probably suggest that you search how to find the hopefully installed driver on your computer, and install, reinstall, upgrade, and or repair that particular driver either by using the Update software on your computer, or by copying and pasting the name of that driver into your Internet browser and go from there.

Thanks, @danj! I have added a screenshot of CoconutBattery.

@cacciatore98762 I agree with Dan. I don't believe it requires a driver because the battery should power the device whether an OS is installed or not, which this particular battery isn't.

Okay cool! I thought it was a driver issue. I want to learn more about this CoconutBattery software that @danj is referring to.

Great, thank you. I pulled MagSafe and it immediately shut down, as if you pulled the plug on a desktop. I'll have to contact iFixit Store.