Nexus 7 Battery Behavior

**fschris** · 01-16-2013, 08:11 AM

Nexus 7 purchased over Christmas shipped to me with 4.2.1

The odd thing is with the battery indicator. We can use the nexus all day and at the end of the day the battery life is still 100%.

But then lets say it then drop to 69% then it will die shortly after. Or it will stay at 100% and then die.

The battery indicator is not properly displaying the current % of life left.

Any thoughts if this is a defective unit or is this a software glitch?

**jblank** · 01-16-2013, 08:56 AM

I doubt it is software. Have you tried doing a restore to the "out of the box" settings? I had some poor battery performance with my Galaxy S3 and did a restore and since then, everything has been perfect.

**fschris** · 01-16-2013, 09:57 AM

I would also like to add, I believe the battery life is pretty good, its the measurement of life that is erratic! How do I perform a system restore ? Is it a setting in the menu or a combination of keys that I press?

**bng2** · 01-16-2013, 01:30 PM

the battery is not accurate, for me, after it charged 100%. It takes 15 minutes for it to go from 100 to 99.

**megagene** · 01-16-2013, 08:51 PM

The exact same thing has been happening to me for the past few weeks and it's driving me insane. Sometimes the battery meter will stay at 100% for more than a day even if I use it for hours. Eventually it will finally start draining and then the battery will die at anywhere between 30 and 50%. I hate it because apparently it isn't good to let the nexus 7 shut down from a completely drained battery, but how the heck am I supposed to know when it's about to die if the battery meter is completely inaccurate?

**tmoneybags** · 01-16-2013, 10:44 PM

When my battery meter gets to around 30 to 35%, it instantly drops to 1% and then powers down.

The battery meter seemed to be working accurately until the last 4 or 5 charging cycles. Now it consistently dies.

**fschris** · 01-17-2013, 05:52 AM

I cant find a system restore option? I'm glad I am not the only one with this issue. I tend to think this is a SW glitch.

**Soundtrack to Chaos** · 01-21-2013, 10:25 PM

I had/have a issue similar to this, it would randomly shutdown around 44 or 48 %, claiming that the battery was low

I've been coin p doing some research and from my findings, apparently, the indicator was actually wrong and it truly was at 0%

What I did was fully charge it, posted with it for a while and brought it down to 66% and then turned it off, when I turned it on in the morning, it actually gave me a low battery warning and said the battery was at 6%

So I fully charged it and am currently running it down with normal usage yo see if it will auto shutdown now, or if the problem is fixed

Sent from my Google Nexus 7 running aokp 4.1.2, because there is no PacMan rom for the nexus

**Soundtrack to Chaos** · 01-21-2013, 11:10 PM

Originally Posted by fschris

I cant find a system restore option? I'm glad I am not the only one with this issue. I tend to think this is a SW glitch.

Weird thing for me is that I'm getting this issue on a 4.1.2 ROM

I think it's because I came from a 4.2 ROM prior

Sent from my Google Nexus 7 running aokp 4.1.2, because there is no PacMan rom for the nexus

**jpash549** · 01-22-2013, 01:46 AM

Suggest getting a battery monitor such as Gauge Battery Widget. This will give you more info such as voltage and temperature as well as an estimation of rates of use or charge. But this info is supplied by the Nexus 7 operating software and so it may also be messed up. But you can look at the battery voltages. For 100% charge the voltage would be about 4.17 volts and for <5% about 3.42 to 3.5 volts. These voltages are set by the maker to denote ends of the useful operating range. If you use the device for a while and the voltage does not show a decrease would seem to me that something needs to be fixed. Maybe it is a software problem. Sometimes going through charge/discharge cycles does improve things.

Sent from my Nexus 7 using Android Central Forums

**Soundtrack to Chaos** · 01-22-2013, 10:33 AM

Originally Posted by jpash549

Suggest getting a battery monitor such as Gauge Battery Widget. This will give you more info such as voltage and temperature as well as an estimation of rates of use or charge. But this info is supplied by the Nexus 7 operating software and so it may also be messed up. But you can look at the battery voltages. For 100% charge the voltage would be about 4.17 volts and for <5% about 3.42 to 3.5 volts. These voltages are set by the maker to denote ends of the useful operating range. If you use the device for a while and the voltage does not show a decrease would seem to me that something needs to be fixed. Maybe it is a software problem. Sometimes going through charge/discharge cycles does improve things.

Sent from my Nexus 7 using Android Central Forums

All the battery reading apps say the same thing that the battery indicator says

Sent from my SPH-L710 using Android Central Forums

**clankfu** · 05-03-2013, 11:39 PM

Did anyone find a solution to this problem? I've been experiencing the same thing for the past week or so. It'll stay at 100% for a long time and automatically shuts down at around 20-30%.

**jpash549** · 05-04-2013, 01:04 AM

Originally Posted by Soundtrack to Chaos

All the battery reading apps say the same thing that the battery indicator says

Sent from my SPH-L710 using Android Central Forums

The point was to see what the voltage indicated was. If it decreases normally with use then battery percentage calculation is at fault. If the voltage, current or temperature values are off there may be a hardware problem which should be noted under warranty. Of course you are correct in that the app will only report values provided by the system. Since the system does shut down after a period of use the voltage should have dropped from full charge value of 4.17 volts to something like 3.53 volts. What the battery percentage says is really not a problem but is certainly confusing and irritating if the calculation is wrong.

From my N7 or BBPB or HPTP or HP Laptop