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Completely Clueless 07-24-2010 07:27 AM

Smartphone battery life
 
Hi all,
Does anyone know why these smartphones have such short battery lifes? I don't mean the batteries wearing out early, but rather the fact that they run down so quickly. I have seen manufacturers' claims for some models that they retain a charge for up to 600 hours on standby, but then when you read the customer reviews and see so many users complain they have to recharge them every day!

Are there any models that provide superior battery life, or can one configure them to consume less juice?

Thanks, cc.

GrapefruiTgirl 07-24-2010 07:35 AM

600 hrs on standby is probably possible, at ideal operating temperature and with the phone never ringing and never being picked up, opened or turned "on", and with no backlight or kbd lights, and not connected to the internet, and not running any applications in the background, and very close to the nearest tower it connects to so as to use as little transmitting power as possible...

I'd wager the primary reason for early battery drainage is internet usage (which means images, image processing (scrolling, enlarging, etc..) and FLASH/Video (or it's smart-phone equivalent is). Video and graphics, just like with a PC or laptop, is going to suck the power the worst..

Completely Clueless 07-24-2010 09:22 AM

I see. So the key to getting good battery life is not to use the phone at all. Figures.

GrapefruiTgirl 07-24-2010 09:26 AM

Pretty much.. Those specs given by many manufacturers of many products, do not reflect real-life situations or usage at all.

Consider CFL's (Compact Fluorescent Lights - or ANY fluorescent light for that matter) which boasts "10,000 hours lifespan". Well sure, the thing may turn on and emit light for 10,000 hours or more - but, by the time 3,000 or 5,000 hours has ticked by, the emitted light is so degraded, discolored & dim, that you pretty much need to replace the bulb anyways, making the 10,000 hour figure irrelevant.

Completely Clueless 07-24-2010 10:09 AM

I am sure you are right. I just read elsewhere that it is now considered pretty meaningless to quote battery life figures for smartphones in the same context that is used for regular cellphones (standby and talktime) as they are extremely misleading.
Thanks for your thoughts.

salasi 07-24-2010 02:46 PM

Quote:

Originally Posted by Completely Clueless (Post 4043975)
...it is now considered pretty meaningless to quote battery life figures for smartphones in the same context that is used for regular cellphones...

Yes, good standby times can be achieved when the phone does nothing, but
  • All of the social networking stuff does lots of contacting the server (push or pull) and checking whether there is new information to be transferred and probably sorting of lists, etc, etc and that means that the processor never really goes to sleep for extended periods. The testing is always done without the social networking features doing this stuff, so that is unrealistic, but then, how much social networking would be realistic?
  • Anything with a touch screen means that the the processor spends a lot of time looking for any activity with the screen, so that stops the processor going to sleep much, either, so that puts a limit on battery life, even if that ought be something that is covered in the original testing.

Completely Clueless 07-24-2010 04:15 PM

Quote:

Originally Posted by salasi (Post 4044141)
Anything with a touch screen means that the the processor spends a lot of time looking for any activity with the screen, so that stops the processor going to sleep much, either, so that puts a limit on battery life, even if that ought be something that is covered in the original testing.

In that case it would make sense for the screen and the processes that monitor it to just go to sleep after some predetermined interval so the user can wake it up with a button press someplace.

I'm not interested in social networking sites so those apps will be never be used. I shall be mainly using it for navigation (GPS) and checking websites at wireless access points.

salasi 07-25-2010 06:47 AM

Quote:

Originally Posted by Completely Clueless (Post 4044232)
In that case it would make sense for the screen and the processes that monitor it to just go to sleep after some predetermined interval so the user can wake it up with a button press someplace.

The processor has to scan whatever is used to wake up the phone again, or it can never wake up. Many of the smartphones use the screen for wakeup, so if you don't scan the screen it doesn't wake up. With a button, if you scan that, you have to do less and it takes less energy, That is an advantage. if you get an interrupt from the button, you don't have to do the periodic scanning thing, but that depends on how the phone system is constructed.

Quote:

Originally Posted by Completely Clueless (Post 4044232)
I'm not interested in social networking sites so those apps will be never be used. I shall be mainly using it for navigation (GPS) and checking websites at wireless access points.

GPS/mapping (the mapping bit is probably much more than the gps chipset itself) is one of the single most power consuming things that you can run; I have an older generation smartphones with an external gps puck and running gps/mapping knocks the battery life down from nearly two weeks, under optimal conditions, down to just over two hours. This is not ideal...but in a car, its not an issue, because you can plug in to the car's electricity, and there is plenty of that.

Completely Clueless 07-25-2010 10:03 AM

Quote:

Originally Posted by salasi (Post 4044684)
GPS/mapping (the mapping bit is probably much more than the gps chipset itself) is one of the single most power consuming things that you can run; I have an older generation smartphones with an external gps puck and running gps/mapping knocks the battery life down from nearly two weeks, under optimal conditions, down to just over two hours. This is not ideal...but in a car, its not an issue, because you can plug in to the car's electricity, and there is plenty of that.

Wow! Thanks, Man. That's really useful to know. I never knew GPS-positioning was so current-thirsty. :-/

salasi 07-25-2010 02:19 PM

Just for clarity, this really is an older generation phone. The processor is slower and less efficient. There is a lot of math to be done in the mapping part.

It is not going to anywhere that extreme on a phone with a more efficient processor (higher clock rate, and hence throughput, at a similar level of consumption) but it is still going to be a relatively big consumer. I have, in the past, managed accidentally to leave the sat nav program running in the background and suddenly being shocked to see where the battery level had gone down to.

sophiadavid01 07-31-2010 12:37 AM

Yes, I am agree that Smartphones's batteries has shortest life cycle.
I brought smart Phone last year only. I had to change battery last weak only. Because I had to charge a phone twice time a day. So I shown the phone to the person from whom I brought these phone he told me battery period i over you have to change it.

Smophos 08-05-2010 07:29 AM

I don't normally have such a problem with smartphone battery life but I always turn off the 'battery-intensive' features and turn them on when I need them etc

I only have to charge every 2/3 days with my Motorola Cliq :)

Turning down screen brightness works wonders too, you can always turn it up :)

princealway 08-12-2010 12:10 PM

To improve the life of the battery in the smartphones than use follow this :-
Use simple ringtones.
Update your operating system
Talk, don't e-mail
Push less
Turn off unused radios
Watch the time
Use a corded headset
Use auto shut-off


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