mac turning off on it's own

my mac book air has been turning off on it's own recently. It seems to have started after I installed the latest OS update.

The first time it shut off it took a minute or so of me pressing the power button and various keys before it came back on. Just now I had to connect it to power for it to come back.

I have 57 percent battery at the moment and the first time it shut off I believe I had closer to 80 something.

Has anyone else experienced this problem?