That depends on usage - I'm running Windows Insider Fast and Office 365 ProPlus Insider Fast which tend to degrade battery life and I'm getting 8 hours on average.
Things that impact Battery Life on Windows 10 - Chrome, 3rd Party AV/Security Suites, Flash, Running with High Brightness, Using Vista/XP era Win32 Applications or Applications that are newer but still use standards from that era (i.e iTunes, VLC Desktop).
Mine would last about 8 hours with light load (basically just typing text with occasional websearch), so I imagine it would go down to 5-6 hrs if doing something heavier too. The battery is not particularly impressive.
I did read somewhere about people getting better battery life after fixing the auto-hibernate issue, though. So maybe try to focus on this first. Contact the AnswerDesk guys for help - they helped me with my auto-hibernate issue by reinstalling some firmware and re-imaging the device.
Up to 13.5 hours of video playback. Testing conducted by Microsoft in April 2017 using preproduction Intel Core i5, 256GB, 8GB RAM device. Testing consisted of full battery discharge during video playback. All settings were default except: Wi-Fi was associated with a network and Auto-Brightness disabled. Battery life varies significantly with settings, usage and other factors