I have Install Ubuntu 18.04.Battery is draining very quickly approx 1:30 hr only. while in window same laptop have upto 4:50 hr battery. I have Lenovo Ideapad 310 (i5 6th gen).
First, read this Ubuntu Help article about Power & battery
If not enough you may want to install TLP
TLP brings you the benefits of advanced power management for Linux without the need to understand every technical detail. TLP comes with a default configuration already optimized for battery life, so you may just install and forget it. Nevertheless, TLP is highly customizable to fulfill your specific requirements.
To install TLP :
sudo apt install tlp tlp-rdw sudo tlp start
Then customize suspend setting: System Settings -> Power -> Suspend & Power Button.