A Sane Thread on Battery Life!!!

[AshleyDel]

I have read countless posts on battery life and they drive me crazy!! Here are the only criteria that I believe should matter:

1-How many hours of reading a day

2-Screen brightness of touchscreen(bottom screen)-set to lowest-2% for me

3-wifi mode off and Airplane mode must be on

4-Always leave in sleep mode unless not using for an extended amount of time(or, as some purists would say, if on a plane. Though I would just put the Nook into Airplane Mode on)

You cannot take any reliable reading of battery life with the 3G and WIFI network on

You cannot measure battery performance unless you include the number of hours read over a certain period of time.

You cannot say something lasted x days when some days you read 1 hour and some days 5 hours-that  tells us nothing.

My experience with the 1.2 update(given the above criteria) has been 3 hours a day for 4 full days and battery went from 100% to 65%. Then I turned Airplane mode off for 30 mins and went shopping.....it went down to 57%. So with Airplane Mode on-no Internet or WIFI, I get about 3% of battery use per hour of reading. If I leave overnight in sleep mode it goes done by about 2% every 8 hours.

I have fully discharged the Nook once, otherwise I just keep topping up, since I get a lot of books from Fictionwise etc and need to connect the Nook to my laptop to download files.

I would be interested in what everyone else is getting.

[eagleSB]

There's a thread that was already doing this.  Granted, it was before 1.2, but very similar to your thoughts here.

http://bookclubs.barnesandnoble.com/t5/eBooks-Help-Board/Post-Your-Battery-Experiences/td-p/442664

[GeoffreyF]

First ... if you did not fully charge your nook (as the instructions say) before first using it off the charger then you may have ruined the battery.  All bets are off.

Second ... the battery performance has improved with the latest update.  All posts more than a week old are not entirely relevant.

Finally ... the more you use the LCD and network features, the worse the battery performance.  These are natural things to do when you first get your new toy though.

In an all day read of the nook ... pretty much all day, but with some messing around with the LCD and Network, I use up about 40%.    That's fine for me.  In "Airplane mode", I'll bet it is alot better.   I am very confident that a fully charged nook will last through a very long day.  I'd say easily 15 hours of near constant activity.

[icebike]

---

GeoffreyF wrote:

First ... if you did not fully charge your nook (as the instructions say) before first using it off the charger then you may have ruined the battery.  All bets are off.

---

Well you are the first to say that.  Citation Needed.  

Even B&N makes no such claim.

[Ed_Mart]

I've seen no difference in battery life between 1.1.1 and 1.2. 

I get 2 to 3 days from a full charge, but then, I leave wifi on and airplane mode off, my touchscreen is set at 20% luminosity and 30 seconds to off.  It is set to go into sleep mode after 5 minutes.  My average read time is between 4 and 6 hours a day and occasionally browsing for new books. 

I have no complaints, charging it when it needs it is not a problem.

[Tammke]

I've had my nook for about a week and also only get about 2 to 2 1/2 days of life out of the battery.  I contacted customer support today via e-mail and was told that the short battery life is a documented problem with the battery management system and there is a software update in the works to address it.  No time line on how long it's going to take to get the update out, but hopefully it will be soon.

[eagleSB]

Interesting.  I thought they addressed it in the last update.  Apparently theres more work to do.

[BartleyR7]

---

GeoffreyF wrote:

First ... if you did not fully charge your nook (as the instructions say) before first using it off the charger then you may have ruined the battery.  All bets are off.

---

This is simply not true (with nook or any other modern-day device that uses lithium-ion or lithium-polymer batteries).  These types of batteries do not develop a memory like NiCd batteries did.  Please stop implying that this is the case.  There are ways to ruin a li-ion and li-poly battery (too much voltage/current supplied to the battery and temperature extremes being two of the most common), but it is not possible to "ruin the battery" by simply not charging it sufficiently (first time or not).

If you didn't charge it fully before using, the worst thing that might happen is a mis-calibration in the charging circuitry of nook.  In short, there is circuitry built into modern devices that allow them to monitor and report the amount of battery life remaining.  It is sometimes necessary to calibrate this circuitry by fully charging then discharging the battery.  Think of it as establishing an upper- and lower-bound for the battery life.  (That's not exactly what happens, but it's sufficient to adequately explain what's happening.)  If nook thinks that your battery is completely charged but, in reality, it is only 60% charged, then you will see the battery go from 100% to 0% very quickly.  In reality, the battery was discharging from 60% to 0%.  (I made those numbers up, but you get the idea.)

This is the reason why most manufactures recommend that you fully charge/discharge your device once every so many months (three to four is typical).  Like all rechargeable batteries, these li-ion and li-poly batteries do lose charge capacity over time.  The capacity is typically given in mA, and manufactures will say something like "battery good for 500 load cycles" or "battery good for 500 cycles."  This means that you can fully charge/discharge the battery 500 times before it will "fail" (not hold a sufficient charge).  What makes this technology great is that it does record partial charges.  For example, if your nook is 50% charged and you fully charge it, this does not count as a "full cycle."  If you did this again (charge from 50% to 100%), then you will have used one load cycle of your battery.

You may have a defective battery, but you probably did nothing to cause its poor performance.  I would suggest fully charging/discharging the battery 2-3 times and see if you performance improves.  Good luck!

[AmyK67]

---

icebike wrote:

---

GeoffreyF wrote:

First ... if you did not fully charge your nook (as the instructions say) before first using it off the charger then you may have ruined the battery.  All bets are off.

---

Well you are the first to say that.  Citation Needed.  

Even B&N makes no such claim.

---

GeoffreyF is also the poster who (when I suggested it) told a newbie that she should NOT plug her frozen Nook into the wall without the battery or it would fry the insides or something like that. I'd like to see citations too.

[Tammke]

--

Interesting.  I thought they addressed it in the last update.  Apparently theres more work to do.

--

I received my nook on Feb. 3rd, so I only had it one full day before the 1.2 update came out.  I saw that a lot of people said that 1.2 improved their battery life, but mine is still terrible so I hope they really are working on a fix. 

Other than the battery issue,  the nook is a great device.  It probably is the best device I've used so far for handling the ePub format and has the absolute best eInk screen.

[eagleSB]

you should try letting it run down and fully charge it a few times.  my battery life is pretty good.  the nook needs to learn where fully charged and fully discharged are on the battery so it knows how much is left.

[LarryGanz]

I have airplane mode on (i.e. radios off), with LCD backlight at about 25%, and read 2 hours a day, and I am down to about 18-20% every weekend when I charge once a week.  I usually have one long book loaded, and don't use the LCD screen very much, since I am not switching books and shopping (I have loads of books already).  

However, if I don't touch the nook it seems to drain at about that same rate, I presume because Android OS is doing things in the background all the time (including waiting for the next screen saver refresh).  I suspect that if all I am doing is page turns and leaving the LCD alone, that I could double my reading and still only have to charge once a week.

I just did the 1.2 update 2 days ago so I am charging today, which a day or two early in order to get an idea of how well it lasts after the update.  I had about 40% of battery left and it was last charged on Saturday.  If the nook had a backlight I would read an extra 2-3 hours with it every night, but I switch to my iPhone so as to not disturb my wife at night.  I really want to see the iphone and nook communicate about what the last page I read was, and to have them share bookmarks.

[nookie01]

I think that number of page turns account for as much, or even more, than actual number of hours read. Person A could read 100 pages in an hour, Person B could read 150 pages in that same hour. Person B is likely to drain more battery than Person A because turning the page consumes more battery than looking at the eInk screen. 50 additional pages per hour over an extended period of time is going to add up to a whole lot more battery consumption.

[AshleyDel]

Good point indeed nookie01....I hadn't thought of that in my original criteria. Supposedly there is no power used when looking at the einkscreen-unless the backlight is on in the lower screen, However, I know for a fact that is not true...since the lower screen, even though it can be dark, is still an active touchscreen: so it must always be ready to receive finger swipes etc. In other words, if the unit is on-even though no pageturns occur-there is still approx 3% per hour drain on my Nook. I tried this with and without pageturns- set the Nook to stay on for the max of 20 mins before sleep. I tried slow and fast reading simulations-still drained 3% on my Nook in an hour. I personally believe that the Nook never really depicts an accurate battery reading. Certainly the battery meter at the top may show virtually 90% full but my Nook can read 68%!!!! I hope that future updates can fix these problems....

[AshleyDel]

I have to say that that even though the battery life, for me anyway, has improved considerably with the latest update-it is only apparent when I read. If i use the touchscreen and/or the shopping mode then any savings in battery life get wiped out in 30 minutes of "special use'. So the 1.2 update I believe, helps with reading life, but does not address the battery drain when connecting to wifi or 3G. A lot of people-not necessarily myself-bought the Nook because of the much vaunted touchscreen and shopping experience. Well B and N, please take note!!! If you want to increase your client base and create loyal existing customers, then I suggest uou work on a software fix for the wireless battery drain. If it can be done that is.... The Kindle can do it since there is no backlit touchscreen involved. Can the Nook do the same I wonder? I own both devices,in between charges I use the Kindle(lots of books from Fictionwise work on both): However the Nook is my preference since it has a substantially better, brighter and clearer eInk screen....IMHO