Not had this device long. Have downloaded a few books but only read say 5 pages and my battery is 33%! Unable to switch it off totally. Unimpressed!
Assuming you're referring to a Kindle rather than a Fire tablet, battery life is dependent on a number of factors - it will be shortened by keeping WiFi on, by downloading lots of books at once (which all need indexing) and by having the screen brightness up high.
Amazon's advertised 'weeks' of battery life are based on only 30 minutes of use per day and keeping WiFi off, as well as not having the brightness up all the way.
most Kindles only have 21-28 hours of battery life with wireless off, illumination set to 10 (too low in my opinion) and no books indexing. Since I read with my light set to 18 or 20 depending on which device I use and I'm a speed reader (= more page turns = more battery usage) plus I read 3-4 hours per day, I need to charge every 2-3 days
I have a 1+ year old (gen 9) Oasis. These are the same settings and usages I have had in place since I bought it in March of 2018: always have wifi on, often have bluetooth on, clock on, page in book on, light level usually 10 or on auto bright, color inverted about half the time. I generally read at least an hour, sometimes 2, at least once a day. I use a cover that automatically puts it into sleep mode when I close it.
My battery life has reduced significantly in the last few (6-8?) weeks. When I first received the Oasis, the battery would last 2-3 weeks without needing a charge. Now it will only last a day, maybe 2 at most.
I am updated to version 5.12.1. I have 26GB free space.
I noticed that after the Read/Unread option appeared. Also, check to see if you have a book stuck indexing:
1. search for a nonsense word like fjgalhg
2. tap on the Search Everywhere
3. look at the Text in Books. If it's grey, all your books are indexing, if it's black they aren't so tap on tha and see what has yet to index
if you were reading 3 weeks at an hour per day before having to charge your battery, you were possibly getting above normal battery life with wifi on and light above 10
2 weeks X 7 days X 1 hour = 14 hours
3 weeks X 7 Days X 1 hour = 21 hours
Amazon says: "A single charge lasts up to six weeks, based on a half hour of reading per day with wireless and Bluetooth off and the light setting at 10. Battery life will vary based on light settings, wireless usage."
6 weeks X 7 Days X .5 hours = 21 hours
I am running the same OS on a Voyage and a paperwhite 10 and I have to charge every other day because I read fast (more page turns = more battery usage), have my light set higher and read 4-5 hours per day