Hi,
Please read the following test (under section Battery life):
http://www.laptopmag.com/reviews/laptops/hp-chromebook-pavilion.aspx
"The HP Pavilion 14 Chromebook performed better on the LAPTOP battery test (Web browsing over Wi-Fi with 40 percent screen brightness) than we were expecting. The 4-cell 2.55Ah lithium-ion battery in this notebook lasted a full 5 hours and 29 minutes, ..."
Regards.