It is an Windows default action to put on hibernate mode the laptop when battery run off less than 5% of charge.
I had the same problem. What you have to do is to go through energy options > advance options, click on allow highlighted advice (to allow modify information not available). Afterwards look for Battery options and on this expanded list pick up the "do nothing" under "critical level of battery action".
You have to try hard and for many times due to the hibernate default problem after 4 or 5 seconds.
Good luck,