Go Back   AnandTech Forums > Consumer Electronics > Mobile Devices & Gadgets

Forums
· Hardware and Technology
· CPUs and Overclocking
· Motherboards
· Video Cards and Graphics
· Memory and Storage
· Power Supplies
· Cases & Cooling
· SFF, Notebooks, Pre-Built/Barebones PCs
· Networking
· Peripherals
· General Hardware
· Highly Technical
· Computer Help
· Home Theater PCs
· Consumer Electronics
· Digital and Video Cameras
· Mobile Devices & Gadgets
· Audio/Video & Home Theater
· Software
· Software for Windows
· All Things Apple
· *nix Software
· Operating Systems
· Programming
· PC Gaming
· Console Gaming
· Distributed Computing
· Security
· Social
· Off Topic
· Politics and News
· Discussion Club
· Love and Relationships
· The Garage
· Health and Fitness
· Merchandise and Shopping
· For Sale/Trade
· Hot Deals with Free Stuff/Contests
· Black Friday 2013
· Forum Issues
· Technical Forum Issues
· Personal Forum Issues
· Suggestion Box
· Moderator Resources
· Moderator Discussions
   

Reply
 
Thread Tools
Old 09-15-2012, 11:38 AM   #1
Eug
Lifer
 
Eug's Avatar
 
Join Date: Mar 2000
Posts: 16,962
Default Nexus 7 charging: How long?

When I woke up this morning, my Nexus 7 was completely dead. That was a surprise to me, because it wasn't near dead when I went to sleep. So I plugged it in and after a few minutes of charging was able to wake it back up. It read battery: 0. After a few minutes I started surfing with it and what not, but after about 5 minutes I got a screen full of snow and it shut off.

So, I left it off, to charge. It's been charging around 2 - 2.5 hours and it's only at 15% now. (I turned it on briefly to check.)

I wonder if there is something wonky with my Nexus 7. I'm using the stock 2A charger and the stock cable, but I seem to remember it charging a lot quicker before.

I'm certainly not getting this charge time:



EDIT:

I just came across this thread:

http://androidforums.com/nexus-7/594...nt-charge.html

Similar symptoms.

Interestingly I had been playing with Stickmount last night, but AFAIK, I had left the USB flash drive unplugged, so it wouldn't have been a source of battery drain.
__________________

OS X: 27" iMac Core i7 870 | 13" MacBook Pro C2D 2.26 P8400 + SSD | 13" MacBook C2D 2.4 T8300 + SSD
iOS: iPad 2 | iPhone 5s
Windows: X3400 Athlon II X3 435 | 11.6" 1810TZ Pentium SU4100 + SSD | Revo R3610 Atom 330 + SSD
Android: Nexus 7 (2012)

Last edited by Eug; 09-15-2012 at 11:45 AM.
Eug is offline   Reply With Quote
Old 09-15-2012, 11:40 AM   #2
dguy6789
Diamond Member
 
dguy6789's Avatar
 
Join Date: Dec 2002
Location: San Antonio, TX
Posts: 8,375
Default

Go to settings and battery and it should say charging and then either USB or AC in parenthesis. If it says USB then unplug and plug it back in and see if it changes to AC. I have noticed some devices charge in USB speed for some reason when plugged into an AC outlet and need to be unplugged and plugged back in again sometimes to fix it.
dguy6789 is offline   Reply With Quote
Old 09-15-2012, 11:50 AM   #3
Ravynmagi
Platinum Member
 
Ravynmagi's Avatar
 
Join Date: Jun 2007
Location: Phoenix, Arizona
Posts: 2,489
Default

Because it's discharging so fast and charging so slow, it sounds like it's wonky. Mine charges pretty quick, I'd say 3 hours for a full charge is about right, mine charges less since I rarely get that low.

My battery life has been pretty excellent. You might have some app going crazy or maybe a hardware defect. Reboot if you haven't yet. Next I'd probably try backing up and doing a factory reset.
__________________
Intel i5-2500K 4.0GHz, 16GB, ASUS P8Z68-V/GEN3, GTX 680, Intel 520 Series 180GB
Seasonic M12 700 watt, Cooler Master Cosmos S, Scythe Gentle Typhoon 120mm fans

Windows: Dell XPS 12, Dell Venue 8 Pro, Nokia Icon, Nokia Lumia 521
Android: Galaxy Note 3, Nexus 5, Nexus 4, Nexus 7 2013, LG G Pad 8.3, Nook HD+
iOS: iPad Mini with Retina, iPhone 5S
Ravynmagi is online now   Reply With Quote
Old 09-15-2012, 08:46 PM   #4
Eug
Lifer
 
Eug's Avatar
 
Join Date: Mar 2000
Posts: 16,962
Default

Almost 12 hours now. 52%, on AC, with the unit off for most of that time.

Tomorrow is the last day I can get a refund. Maybe I'll do that. Or perhaps I'll unroot and wipe it tonite to see what happens to it. There don't seem to be any wayward apps in the apps list.
__________________

OS X: 27" iMac Core i7 870 | 13" MacBook Pro C2D 2.26 P8400 + SSD | 13" MacBook C2D 2.4 T8300 + SSD
iOS: iPad 2 | iPhone 5s
Windows: X3400 Athlon II X3 435 | 11.6" 1810TZ Pentium SU4100 + SSD | Revo R3610 Atom 330 + SSD
Android: Nexus 7 (2012)

Last edited by Eug; 09-15-2012 at 08:48 PM.
Eug is offline   Reply With Quote
Old 09-15-2012, 11:02 PM   #5
vshah
Lifer
 
vshah's Avatar
 
Join Date: Sep 2003
Location: Pittsburgh
Posts: 18,709
Default

try out better battery stats, but if you only have one day left, i would exchange it.
__________________
Intel Core i7 920 || Asus P6T Deluxe V2 || Noctua NH-U12P|| 12GB DDR3-1600
GTX 670 || Intel x-25m 80gb || 1TB Caviar Black || Antec 902 ||Antec 550w
HEAT
XBL: the4ner85
vshah is offline   Reply With Quote
Old 09-15-2012, 11:08 PM   #6
Spoooon
Lifer
 
Join Date: Mar 2000
Posts: 11,142
Default

Wonky, but I would just exchange if you're still able to.

C90 build impressions: http://forum.xda-developers.com/show....php?t=1888299
__________________
You just got Spoooon fed

- M4H
Flame on!
current desktop
Spoooon is offline   Reply With Quote
Old 09-16-2012, 03:34 AM   #7
BenSkywalker
Elite Member
 
Join Date: Oct 1999
Posts: 8,955
Default

Had you deep cycled the batteries at all since you bought it?

Last couple of 7s I bought I ran them dead then plugged them in, never turned them on, and let them do a full charge- took about 24 hours for them to charge up(each obviously). Since then they haven't come close to going dead, not sure how long it would take now but they are used constantly and only hit the charger every other day.

If you haven't run them all the way dead and done a full charge, you may have not seen the actual capacity of your battery yet.
BenSkywalker is offline   Reply With Quote
Old 09-16-2012, 04:15 AM   #8
Eug
Lifer
 
Eug's Avatar
 
Join Date: Mar 2000
Posts: 16,962
Default

Quote:
Originally Posted by BenSkywalker View Post
Had you deep cycled the batteries at all since you bought it?

Last couple of 7s I bought I ran them dead then plugged them in, never turned them on, and let them do a full charge- took about 24 hours for them to charge up(each obviously). Since then they haven't come close to going dead, not sure how long it would take now but they are used constantly and only hit the charger every other day.

If you haven't run them all the way dead and done a full charge, you may have not seen the actual capacity of your battery yet.
Never all the way dead, but to less than 10% a few times. With your 24 hours statement it sounds like your experience is similar to mine. However that doesn't jive with the Anandtech review saying it it should take just a few hours, nor my experience with the under 10% to full charges either, which also took just a few hours.

BTW, after the device hit 52% (after 11+ hours) it charged to full in a couple of hours.
__________________

OS X: 27" iMac Core i7 870 | 13" MacBook Pro C2D 2.26 P8400 + SSD | 13" MacBook C2D 2.4 T8300 + SSD
iOS: iPad 2 | iPhone 5s
Windows: X3400 Athlon II X3 435 | 11.6" 1810TZ Pentium SU4100 + SSD | Revo R3610 Atom 330 + SSD
Android: Nexus 7 (2012)
Eug is offline   Reply With Quote
Old 09-16-2012, 04:56 AM   #9
BenSkywalker
Elite Member
 
Join Date: Oct 1999
Posts: 8,955
Default

Quote:
Never all the way dead
This can make a *huge* difference. It's a bit complicated, but batteries aren't like gas tanks, they work on chemical reactions, and ideally they will be 'trained' so the device they are in knows when they are actually dead and when they are actually full. With advances in technology, the devices we have today do a better job at 'guessing' out of the box, but it isn't comparable to an actual 'deep cycle' recharge.

At this point my 7s will charge to full in probably four hours from under 5%, I will kill them every other month or so and do another deep cycle on them which will again take ~24 hours(probably, haven't done a second deep cycle on them yet).

The device must be powered off for a deep cycle charge to work properly, and stay off(you can look at the battery indicator on the 7 as long as you don't boot it, mine took ~10 hours to go from 98% to full). Now the batteries last significantly longer then my first run down(both of them indicated they were over 50% when unboxed, both dead in ~4.5 hours looping the Transformer movie at max volume that came with them, they now are closer to 6-6.5 hours under the same situation).

Here is a link that gives a brief breakdown-

http://www.atbatt.com/faq/1.asp

After you do a deep cycle, you should be in line with Anand's test results in terms of charging(ball park) but you are likely to see a sizeable performance improvement.

Pretty much, you may have only been using from 2%-38% of your Nexus 7's battery based on what it indicated, a quick charge works fine when the device knows the exact parameters of your battery, but if it doesn't the only way to find out what the upper limits of it are are to 'trickle charge' it so you don't damage the battery. That is why it takes so long when you run it all the way dead. Once you do this once, your device will know exactly where the battery ideals are and you should be good to go for a while(honestly, the once every couple months that I do it is probably a bit excessive, I can tell you one of my kids got an identical phone to mine and was getting half the battery life I was after eight or nine months, he deep cycled it once and was back to in line with mine).
BenSkywalker is offline   Reply With Quote
Old 09-16-2012, 08:44 AM   #10
T_Yamamoto
Lifer
 
T_Yamamoto's Avatar
 
Join Date: Jul 2011
Location: North Carolina State University
Posts: 13,661
Default

I'm pretty sure most devices stop charging at 99. My gnex will never go above 99 (rooted. Deep cycled)
__________________
i5 4430 | MSI B85M-P33 | Gigabyte Windforce R9 270x | Random 4gb + 2gb RAM
XFX ProSeries 450W | Intel 530 128gb + Toshiba Canvio 1tb External HDD | Windows 7
NZXT Vulcan | Dell E2414H
Heatware | Steam
T_Yamamoto is offline   Reply With Quote
Old 09-16-2012, 09:26 AM   #11
Eug
Lifer
 
Eug's Avatar
 
Join Date: Mar 2000
Posts: 16,962
Default

If anything my battery life may be worse now. I've gone from 100 to 49 in about 2.5 hours of just surfing, with the occasional lolcat video.

Before this incident, it'd be at say 80% with similar usage.

Mind you, I left it on all night with the screen off and it was still 100% in the morning.

So maybe its just that the battery indicator is borked. Either way it is pretty damn irritating.

---

Down to 46% since starting this post.

P.S. I deep discharged my first Nexus 7 and it didn't show the same behavior, and I've never seen this behavior with my iPad or iPhone either. I'm beginning to wonder if the Nexus 7 is just a poor quality product, given that my first two had the screen lift issue.

Today is the last day for the return. If I do return it, the question is if I go for number 4 or just cut my losses and wait for the next 7" Samsung or something.

Now down to 44%.
__________________

OS X: 27" iMac Core i7 870 | 13" MacBook Pro C2D 2.26 P8400 + SSD | 13" MacBook C2D 2.4 T8300 + SSD
iOS: iPad 2 | iPhone 5s
Windows: X3400 Athlon II X3 435 | 11.6" 1810TZ Pentium SU4100 + SSD | Revo R3610 Atom 330 + SSD
Android: Nexus 7 (2012)

Last edited by Eug; 09-16-2012 at 09:41 AM.
Eug is offline   Reply With Quote
Old 09-16-2012, 09:54 AM   #12
Demo24
Diamond Member
 
Demo24's Avatar
 
Join Date: Aug 2004
Location: North GA
Posts: 7,812
Default

There's something quite wrong, either a stray app or a hardware issue. I'd factory reset it.
__________________
.........
Demo24 is offline   Reply With Quote
Old 09-16-2012, 10:09 AM   #13
soccerballtux
Diamond Member
 
soccerballtux's Avatar
 
Join Date: Dec 2004
Posts: 9,909
Default

yes check stray app
__________________
HOW TO nested quote
Install this into Firefox then click this, then click "quote" as usual, then click "Nested Quote" to the right of the title bar.
4.0Ghz&2.6Ghz-CPU-NB Ph2-965BE || GA790X-UD4P 8GB DDR800 || Gigabyte GTX670 || Soyo 24" PMVA Heatware
soccerballtux is offline   Reply With Quote
Old 09-16-2012, 04:18 PM   #14
Eug
Lifer
 
Eug's Avatar
 
Join Date: Mar 2000
Posts: 16,962
Default

I couldn't find any stray apps, and reboots didn't help.

However, I've now factory reset it. In fact, it's now no longer rooted, and it's now locked. Behaviour so far seems more normal, but we shall see.
__________________

OS X: 27" iMac Core i7 870 | 13" MacBook Pro C2D 2.26 P8400 + SSD | 13" MacBook C2D 2.4 T8300 + SSD
iOS: iPad 2 | iPhone 5s
Windows: X3400 Athlon II X3 435 | 11.6" 1810TZ Pentium SU4100 + SSD | Revo R3610 Atom 330 + SSD
Android: Nexus 7 (2012)
Eug is offline   Reply With Quote
Old 09-16-2012, 04:26 PM   #15
Spoooon
Lifer
 
Join Date: Mar 2000
Posts: 11,142
Default

Quote:
Originally Posted by Eug View Post
I couldn't find any stray apps, and reboots didn't help.

However, I've now factory reset it. In fact, it's now no longer rooted, and it's now locked. Behaviour so far seems more normal, but we shall see.
I would get a return and give it another go just in case. I think it's a high quality product suffering at times from manufacturing difficulties. Which is definitely frustrating, but mine has filled a niche I didn't realize I had.
__________________
You just got Spoooon fed

- M4H
Flame on!
current desktop
Spoooon is offline   Reply With Quote
Old 09-16-2012, 05:13 PM   #16
Eug
Lifer
 
Eug's Avatar
 
Join Date: Mar 2000
Posts: 16,962
Default

Too late now. Stores are closed and today was my last day. If I return it, it will have to be under warranty now, which is fine I guess. 50 weeks left.

I was a bit worried that unit #4 would give me a screen lift issue or stuck pixels or something. (Luckily, this one has neither.) It seems Google/Asus's QA on these isn't the greatest.
__________________

OS X: 27" iMac Core i7 870 | 13" MacBook Pro C2D 2.26 P8400 + SSD | 13" MacBook C2D 2.4 T8300 + SSD
iOS: iPad 2 | iPhone 5s
Windows: X3400 Athlon II X3 435 | 11.6" 1810TZ Pentium SU4100 + SSD | Revo R3610 Atom 330 + SSD
Android: Nexus 7 (2012)

Last edited by Eug; 09-16-2012 at 05:16 PM.
Eug is offline   Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 12:23 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.