To test the battery can you do the following:
1) Note the current percentage
2) Play 10 minutes of any youtube video on hq
(here is one in case you need it
YouTube - The National - A Skin, A Night - A Film by Vincent Moon)
3) Note the battery percentage after 10 minutes have gone by.
If you could do a similar test when using the mobile hotspot feature to download a large file on your PC, THAT WOULD BE AMAZING!!!!!
I know it would take 20 minutes but you could answer almost any questions anyone has about battery life with that