Solved My New Battery Does T Fit And Doesn T Work Macbook Air 11

Chosen Solution

The new battery doesn’t fit into my laptop.

Compare the model number on the battery to the replacement battery; it needs to be the same. A lot of 3rd party batteries work across multiple years, but only if they say so when they sell them (2010 only works on 2010, 2011-2015 are compatible, if the seller has designed the battery this way).