On another thread:
https://www.mobileread.com/forums/sho...147#post817147 there is a link to a company that sells rebadged iRex units for the aviation industry, a 24 hour battery life is claimed - which in itself is far more specific than anything iRex themselves have claimed. Quite what the 24 hours amounts to though is not clear. I suspect that 24 hours of looking at aviation charts places a different demand on the battery from 24 hours of reading a text at, say, a page a minute (60 page turns per hour x 24 hours gives only 1440 page turns per charge - I'm never really sure what battery life expressed in page turns means either).
In real world use, I read for between 3 and 4 hours a day, I often flip between the things that I am reading - which presumably draws more power that just reading - when we get the firmware updates I imagine I will use annotations and scribble quite a bit, which will also impact on how much power is drawn from the battery. So I guess the real answer to the question, "What's the battery life of this reader?" is, it depends what you are doing with it.