Chosen Solution

I ordered a 3600mAh Wii U gamepad replacement battery from iFixit, and there appears to be a discrepancy between the battery calibration instructions on the website and the instructions that actually come with the battery. And of course I assume these instructions would apply to ANY lithium ion battery, not just this particular one. The website says: “For optimal performance, calibrate your newly installed battery: Charge it to 100% and keep charging it for at least 2 more hours. Then use your device until it shuts off due to low battery. Finally, charge it uninterrupted to 100%.” The instructions that come with the battery say: “For optimal performance, calibrate your newly installed battery: Drain battery below 10%, then charge uninterrupted to 100%” So, which procedure is correct? The included instructions leave out the first step (“charge it to 100% and keep charging it for at least 2 more hours”).

I do the second option. With older batteries you used to keep them on for a few hours more but I don’t anymore.