Laptop won't exit from hibernation

I have a dell inspiron 3537 and here's my problem 

1>The laptop won't turn on after i close the lid 

-If I keep the lid open it behaves normally up to 30 mins to 1 hour 

-However if it's ore than an hour ,even pressing the power button doesn't help ,the led still shows power for the laptop but it wont turn on 

-If the laptop is completely off then the power button will turn on the laptop but when it goes into sleep mode i need to re insert the battery for it to start working again 

Here's what i have tried to sole the problem 

-removed the battery and ac power and pressed the power button for about 20-30 seconds and then re-inserted the battery (this obviously shuts down the laptop in which case the power button works )

-checked all the driers and nothing sees to be out of place 

PS:Some of the keys on the keyboard do not work but i think that's a keyboard issue which an be fixed fairly easily