As the title suggests, my laptop always automatically disconnects from my wireless when I switch to battery and unplug from the power cable. I then have to restart because my laptop doesn't find any wireless adapter installed.
More about :laptop wireless turning switch battery power
Check your power settings in the power options control panel -- whichever setting you are on, click "change plan settings," then "change advanced power settings." Under wireless adapter settings, power saving mode check to see that it is properly set.