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Battery problems, quirks and issues: Read first.
- Thread starter emellaich
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tibortiger
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Thanks to everybody who posted tips and tricks to conserve power on the device while its running, and thanks to those who posted tips on charging.
I'd like to share what I found out and how I improved my battery life and suggest a possible reason for why this is happening to so many people.
I came very close to returning the phone because of horrible battery life yesterday. My usage is very low - and my battery would barely last half a day on standby with me making 30 minutes of calls, no internet, no gps, no wifi, no push email, no real use of the phone. Because of a crummy experience with Sprint representatives I came close to not only returning the phone but canceling my contract with them after almost 10 years.
After reading all the info I could on the phone I decided to try and recalibrate the battery gauge by doing a deep discharge and full recharge. I turned on everything to consume as much power as possible to make the phone die. However before doing that I downloaded the android battery dog app so I could monitor the battery stats.
The short answer is deep discharge does work, you do have to wait for your phone to shut off and not let you power on, and your battery will die after is goes below 3%.
All the people who say deep discharging a lithium battery is bad are absolutely correct - but letting your phone die after it goes below 3% is not a deep discharge and I have proof.
Let me preface this by saying I am not an expert on batteries, but thanks to google and some careful searching I think I learned enough about batteries and gas gauge ICs and coulomb counting to make some educated guesses.
Some reading if you are interested:
Chapter 2: Battery Chemistries
At the bottom of the page there's a nice picture of a single cell discharge curve.
Here's a great wiki on the technology as well:
Lithium-ion battery - Wikipedia, the free encyclopedia
Now remember that battery dog app I mentioned - go get it, it graphs battery capacity as reported by the phone and also battery voltage as reported by the battery itself.
When I fully charged the phone, battery dog reported 4.2V = 100%, but about 10 seconds after I unplug the charger the phone reports 90%, and a minute later it reports 80%. Why is it doing this? Because the phone gauge has not seen a calibration cycle. The battery cell voltage only dropped from 4.2V to 4.1V yet the phone reported 80% and falling battery life.
As I discharged the battery I got lots of warnings at 15% and it turned off the camera and streaming and other fun things. I had to turn on all the RF stuff and tell it to never sleep and it still took 6 more hours to finally get the phone to shut off. Just before it shut down, the battery gauge reported 3%, but the cell voltage was still 3.6V and when it crossed the 3.5V barrier the phone shut off because the log stopped.
What is magic about 3.5V? Go look at the graph I mentioned above - see the knee just past 3.5V? If you discharge much further the voltage is going to drop like a stone, so to prolong battery life some battery manufacturers tell you to not discharge past 3.5V - if you check the wikipedia article they have this to say:
Lithium-ion batteries should never be depleted below their minimum voltage (2.4 to 2.8 V/cell, depending on chemistry)
So everybody who says "DO NOT DEEP DISCHARGE" is technically correct and the battery will be damaged. However the battery usually has a cutoff device to prevent this level of discharge (depending on how expensive the product is). The battery can still be damaged by self-discharge and aging, which is why shelf life is such a concern with rechargeable batteries. Also, the battery dog app proves that the Samsung developers were even more conservative and shut off the device at 3.5V which is very typical for single cell battery packs.
So discharging your phone to the point where it shuts off is not damage, in fact its part of the normal operation of just about EVERY rechargeable device you have EVER owned.
However some batteries like being deeply discharged more than others and while it will not RUIN your lithium battery you should not make it a habit of constantly running the battery down to minimum charge. Lithium is one of those batteries that likes to have lots of shallow charge and discharge cycles instead of lots of deep discharge cycles. Doing it once in a while will NOT ruin your battery.
So why is this deep discharge "fixing" people's batteries? Its not fixing anything, its calibrating the phone's battery gauge which comes to you in its virgin, uncalibrated state.
Lithium batteries are not dead when they are manufactured, they have initial charge and must be stored with some amount of charge so they can survive packing and shipping and shelf life and whatnot. The self discharge rates are very very low, but they are not zero. So many batteries ship with a partial charge. Lets pick a number: 40%.
But before I go further we really need to define what 40% means. Battery voltage is trivial to measure, battery capacity is not. Each battery has a capacity usually expressed as current/time or 1440mA/hr for example. So if you had a phone that drew 1440mA it would run for 1 hour if that battery was fully charged and you could get 100% of the capacity out of the battery. As batteries age you get less and less capacity out of them and so your device run-time decreases accordingly. Eventually you replace the battery or the device when the run time is intolerably short.
So how do you measure capacity? Well its tricky and involved and prone to errors, which is why nearly everything you've ever owned with a state of charge indicator has pissed you off at some point in your life.
One of the most common methods is to just measure the battery voltage and guess. This method sucks for lots of reasons and most devices today do not use this as it does not take any aging or temperature or other considerations into account. Cheap devices do this because its almost free and its better than nothing, but not by much. Remember that windows 98 laptop that said: "save your work, your battery is at 10%" and no sooner did the "bing" come out of the speaker and next you hear hard disk spinning down? That's a crummy state of charge indicator.
Since lithium batteries are "tricky" to charge (they are not hard to charge they just have stringent requirements) it usually costs money to put some kind of charge controller chip in your rechargeable device to manage this task. Sometimes the money you spend on a charger chip & the parts it needs to work can let you build a rudimentary gas gauge for free. This is what lots of lower end devices do, but not things like laptops.
The higher end devices employ several methods of monitoring charge, and have very sophisticated controllers and algorithms trying to get the best guess possible - this is what you typically see in laptops and they usually employ some version of coulomb counting and possibly impedance tracking.
Anyway, back to why the Moment battery life stinks out of the box. Remember when the Moment arrived in your hands? It was not fully discharged because the Sprint person managed to turn it on, program it for your number and register it with their system. So its likely the initial charge the phone saw when that battery was first installed was about 40% or 50%. The directions which come with everything rechargeable say something like:
"blah blah plug in for lots of hours or overnight blah blah blah before using phone blah blah for maximum battery life blah blah"
I don't know what they said because I didn't read them. I did however charge my phone overnight as its what I normally do with new electronic devices. Now the phone's internal charge controller chip follows a very specific charge profile so it does not overcharge the battery so the phone does not explode into a ball of flame. The charger chip is very concerned with battery cell voltage and as soon as it sees it hit its internal magic number it switches from high current to low current, and when it hits the next magic number it switches off.
Meanwhile your phone's battery gauge is quietly monitoring the battery voltage as well and also the current going into the battery and integrating these over time. This is coulomb counting - they are trying to guess just how much capacity is in the battery by measuring the amount of charge that goes in during charging. Remember that 1440 mA/hour rating? Well if you charge at 1440mA for an hour you'll get the same thing as the discharge capacity.
Great - we're done right? Wrong... not all the energy goes into the battery, some of it gets wasted in the chemical reactions as heat. No problem - we put a temp sensor in the battery pack and we can calibrate out the thermal losses - we're done now right? Well no, the battery charging is influenced by lots of stuff and temperature is only one of them. So lots of companies try to figure out better ways of getting more accurate battery gauges so consumers like you and me get products that don't suck at estimating battery life and we then become happy and become brandy loyal and buy more of the new and improved non-craptacular battery life devices.
Here's a great appnote that goes into excruciating detail far beyond what I've blathered about here:
Lithium-Ion Cell Fuel Gauging with Maxim Battery Monitor ICs - Maxim
So back to the Moment - why does its gauge stink so bad? The answer is it can't help it. Because it never saw your battery before the Sprint person installed it, it never saw that 50% go INTO the battery in the first place. It only sees the cell voltage and so it makes a guess about capacity and displays that for the user.
Then as you actually use the phone, its counting the charge going OUT of the battery and getting VERY NERVOUS so it starts dropping the charge percentage like crazy - even though the cell voltage stays pretty close to the same (check the graphs on the battery dog app to see for yourself). When the gauge estimates you have 15% left and starts turning off all the "Fun" stuff on your phone, you might have 40% left in real life, because at this point the gauge is freaking out and is sure your phone is going to shut off in the middle of that next important phone call. Since the gauge never saw that charge go IN the battery it doesn't want to assume there is lots of charge in the battery just because the cell voltage is normal.
This explains why people who do try to "kill" the battery have such a hard time of it - the phone keeps warning them because it thinks its got 15% or less but the battery will happily keep putting out charge and running the phone. Keep your eye on the cell voltage however, it will eventually get to the magic cutoff point where the now panic stricken battery gauge screams "everybody out of the POOL now!" and shuts the phone off.
So you connect your charger and the gauge has a time-out and does its breathing exercises and goes to its happy place to calm down. It happily counts all the way up from 0% to 100% and when you next run your phone down, it "magically" has 25% more battery life than before.
So why doesn't charging from 15% to 100% fix the problem? Two reasons: first off if your battery is 50% empty and the charger only lets you put in that 50%, if you gauge was at 15% and you add 50% worth of charge you're going to only have 65% of real capacity. The gauge gets confused because it knows 4.2V is a fully charged cell but its only counted 65% of the coulombs - so it lies to you and gives you its best guess, and it tries to get that capacity number closer to what it thinks it should be as the cell voltage drops.
Secondly the gauge needs a large enough delta in charge to trigger the recalibration and clearly 15% indicated (which may be as high as 40% actual charge) is not enough to get it to learn. Eventually it may learn but it will take weeks of daily shallow charges to get there, or it might not ever get there if the discharge depth is shallow enough.
Remember - the battery charger and the battery gauge are related but not the same thing. No matter how long you put the phone on the charger its not going to put more energy into the battery after its cutoff voltage has been reached. Regardless of what the gauge says, when the battery voltage hits that magic number (typically 4.2V for this chemistry) charging is over and it goes into super-low-trickle mode to keep from overcharging the battery. The gauge doesn't count this super low trickle charge as real charging, so it doesn't correct its internal coulomb count.
But when you do the full discharge to where the cell voltage its its lower software cutoff of 3.5V, the battery gauge learns a more correct value for actual battery charge because it gets to see all of that charge go into the battery. The absolute lower limit for cell damage is low enough that normal phone operation would never see that value (somewhere less than 3.0V).
However if you run your phone dead and then put it in storage dead, it continues to self discharge, even if the phone is off. This is where damage can occur because the battery will continue to loose charge and may reach the point where it literally starts chemically self destructing.
Temperature can aggravate this as well, so you should avoid keeping your cell phone in really hot places (like your car in the summer). If its 38C outside (100F) it might be 20C hotter inside your car and still hotter inside your phone because all that battery power makes hot things even hotter. Once you get to 50C, even fully charged batteries start to get permanently damaged and manufacturers actually recommend storing the battery only partially charged. Remember when I said the new battery only had 40% in it? This is part of the reason.
Back to the Moment - why do people say they need multiple deep discharges to get full battery capacity? Well the clever people in the gas gauge business don't like to see large and dramatic changes in battery capacity so they put limits on how much a battery can change in a learning cycle. So the maximum delta may be 20% or 25% per learning cycle. So subsequent discharge cycles get it closer and closer to the real answer.
So there you have it - my best GUESS as to why the initial battery life from the Moment stinks, but how some lucky people can get 10X the life the unlucky ones get.
I don't work for Sprint, I don't work for Samsung, I don't even make battery powered handheld devices. But I do get aggravated when my brand new bling bling Android phone works worse than my 2.5 year old Motorola Q. I get even more angry when some uninformed person at the Sprint store tries to tell me: "that's just how they are, I get 10 hours out of mine on standby, you're LUCKY to get 12 hours". So I did some digging and took my best guess.
I'm sure somebody may say I'm wrong or I only have it partially right - which is fine, that's why we're all in this forum - to get correct answers and useful information.
But for those of you who are not as nerdy as myself I hope I shed some light on this "issue" and even restored your faith in what seems to be a very nice phone.
I'd like to share what I found out and how I improved my battery life and suggest a possible reason for why this is happening to so many people.
I came very close to returning the phone because of horrible battery life yesterday. My usage is very low - and my battery would barely last half a day on standby with me making 30 minutes of calls, no internet, no gps, no wifi, no push email, no real use of the phone. Because of a crummy experience with Sprint representatives I came close to not only returning the phone but canceling my contract with them after almost 10 years.
After reading all the info I could on the phone I decided to try and recalibrate the battery gauge by doing a deep discharge and full recharge. I turned on everything to consume as much power as possible to make the phone die. However before doing that I downloaded the android battery dog app so I could monitor the battery stats.
The short answer is deep discharge does work, you do have to wait for your phone to shut off and not let you power on, and your battery will die after is goes below 3%.
All the people who say deep discharging a lithium battery is bad are absolutely correct - but letting your phone die after it goes below 3% is not a deep discharge and I have proof.
Let me preface this by saying I am not an expert on batteries, but thanks to google and some careful searching I think I learned enough about batteries and gas gauge ICs and coulomb counting to make some educated guesses.
Some reading if you are interested:
Chapter 2: Battery Chemistries
At the bottom of the page there's a nice picture of a single cell discharge curve.
Here's a great wiki on the technology as well:
Lithium-ion battery - Wikipedia, the free encyclopedia
Now remember that battery dog app I mentioned - go get it, it graphs battery capacity as reported by the phone and also battery voltage as reported by the battery itself.
When I fully charged the phone, battery dog reported 4.2V = 100%, but about 10 seconds after I unplug the charger the phone reports 90%, and a minute later it reports 80%. Why is it doing this? Because the phone gauge has not seen a calibration cycle. The battery cell voltage only dropped from 4.2V to 4.1V yet the phone reported 80% and falling battery life.
As I discharged the battery I got lots of warnings at 15% and it turned off the camera and streaming and other fun things. I had to turn on all the RF stuff and tell it to never sleep and it still took 6 more hours to finally get the phone to shut off. Just before it shut down, the battery gauge reported 3%, but the cell voltage was still 3.6V and when it crossed the 3.5V barrier the phone shut off because the log stopped.
What is magic about 3.5V? Go look at the graph I mentioned above - see the knee just past 3.5V? If you discharge much further the voltage is going to drop like a stone, so to prolong battery life some battery manufacturers tell you to not discharge past 3.5V - if you check the wikipedia article they have this to say:
Lithium-ion batteries should never be depleted below their minimum voltage (2.4 to 2.8 V/cell, depending on chemistry)
So everybody who says "DO NOT DEEP DISCHARGE" is technically correct and the battery will be damaged. However the battery usually has a cutoff device to prevent this level of discharge (depending on how expensive the product is). The battery can still be damaged by self-discharge and aging, which is why shelf life is such a concern with rechargeable batteries. Also, the battery dog app proves that the Samsung developers were even more conservative and shut off the device at 3.5V which is very typical for single cell battery packs.
So discharging your phone to the point where it shuts off is not damage, in fact its part of the normal operation of just about EVERY rechargeable device you have EVER owned.
However some batteries like being deeply discharged more than others and while it will not RUIN your lithium battery you should not make it a habit of constantly running the battery down to minimum charge. Lithium is one of those batteries that likes to have lots of shallow charge and discharge cycles instead of lots of deep discharge cycles. Doing it once in a while will NOT ruin your battery.
So why is this deep discharge "fixing" people's batteries? Its not fixing anything, its calibrating the phone's battery gauge which comes to you in its virgin, uncalibrated state.
Lithium batteries are not dead when they are manufactured, they have initial charge and must be stored with some amount of charge so they can survive packing and shipping and shelf life and whatnot. The self discharge rates are very very low, but they are not zero. So many batteries ship with a partial charge. Lets pick a number: 40%.
But before I go further we really need to define what 40% means. Battery voltage is trivial to measure, battery capacity is not. Each battery has a capacity usually expressed as current/time or 1440mA/hr for example. So if you had a phone that drew 1440mA it would run for 1 hour if that battery was fully charged and you could get 100% of the capacity out of the battery. As batteries age you get less and less capacity out of them and so your device run-time decreases accordingly. Eventually you replace the battery or the device when the run time is intolerably short.
So how do you measure capacity? Well its tricky and involved and prone to errors, which is why nearly everything you've ever owned with a state of charge indicator has pissed you off at some point in your life.
One of the most common methods is to just measure the battery voltage and guess. This method sucks for lots of reasons and most devices today do not use this as it does not take any aging or temperature or other considerations into account. Cheap devices do this because its almost free and its better than nothing, but not by much. Remember that windows 98 laptop that said: "save your work, your battery is at 10%" and no sooner did the "bing" come out of the speaker and next you hear hard disk spinning down? That's a crummy state of charge indicator.
Since lithium batteries are "tricky" to charge (they are not hard to charge they just have stringent requirements) it usually costs money to put some kind of charge controller chip in your rechargeable device to manage this task. Sometimes the money you spend on a charger chip & the parts it needs to work can let you build a rudimentary gas gauge for free. This is what lots of lower end devices do, but not things like laptops.
The higher end devices employ several methods of monitoring charge, and have very sophisticated controllers and algorithms trying to get the best guess possible - this is what you typically see in laptops and they usually employ some version of coulomb counting and possibly impedance tracking.
Anyway, back to why the Moment battery life stinks out of the box. Remember when the Moment arrived in your hands? It was not fully discharged because the Sprint person managed to turn it on, program it for your number and register it with their system. So its likely the initial charge the phone saw when that battery was first installed was about 40% or 50%. The directions which come with everything rechargeable say something like:
"blah blah plug in for lots of hours or overnight blah blah blah before using phone blah blah for maximum battery life blah blah"
I don't know what they said because I didn't read them. I did however charge my phone overnight as its what I normally do with new electronic devices. Now the phone's internal charge controller chip follows a very specific charge profile so it does not overcharge the battery so the phone does not explode into a ball of flame. The charger chip is very concerned with battery cell voltage and as soon as it sees it hit its internal magic number it switches from high current to low current, and when it hits the next magic number it switches off.
Meanwhile your phone's battery gauge is quietly monitoring the battery voltage as well and also the current going into the battery and integrating these over time. This is coulomb counting - they are trying to guess just how much capacity is in the battery by measuring the amount of charge that goes in during charging. Remember that 1440 mA/hour rating? Well if you charge at 1440mA for an hour you'll get the same thing as the discharge capacity.
Great - we're done right? Wrong... not all the energy goes into the battery, some of it gets wasted in the chemical reactions as heat. No problem - we put a temp sensor in the battery pack and we can calibrate out the thermal losses - we're done now right? Well no, the battery charging is influenced by lots of stuff and temperature is only one of them. So lots of companies try to figure out better ways of getting more accurate battery gauges so consumers like you and me get products that don't suck at estimating battery life and we then become happy and become brandy loyal and buy more of the new and improved non-craptacular battery life devices.
Here's a great appnote that goes into excruciating detail far beyond what I've blathered about here:
Lithium-Ion Cell Fuel Gauging with Maxim Battery Monitor ICs - Maxim
So back to the Moment - why does its gauge stink so bad? The answer is it can't help it. Because it never saw your battery before the Sprint person installed it, it never saw that 50% go INTO the battery in the first place. It only sees the cell voltage and so it makes a guess about capacity and displays that for the user.
Then as you actually use the phone, its counting the charge going OUT of the battery and getting VERY NERVOUS so it starts dropping the charge percentage like crazy - even though the cell voltage stays pretty close to the same (check the graphs on the battery dog app to see for yourself). When the gauge estimates you have 15% left and starts turning off all the "Fun" stuff on your phone, you might have 40% left in real life, because at this point the gauge is freaking out and is sure your phone is going to shut off in the middle of that next important phone call. Since the gauge never saw that charge go IN the battery it doesn't want to assume there is lots of charge in the battery just because the cell voltage is normal.
This explains why people who do try to "kill" the battery have such a hard time of it - the phone keeps warning them because it thinks its got 15% or less but the battery will happily keep putting out charge and running the phone. Keep your eye on the cell voltage however, it will eventually get to the magic cutoff point where the now panic stricken battery gauge screams "everybody out of the POOL now!" and shuts the phone off.
So you connect your charger and the gauge has a time-out and does its breathing exercises and goes to its happy place to calm down. It happily counts all the way up from 0% to 100% and when you next run your phone down, it "magically" has 25% more battery life than before.
So why doesn't charging from 15% to 100% fix the problem? Two reasons: first off if your battery is 50% empty and the charger only lets you put in that 50%, if you gauge was at 15% and you add 50% worth of charge you're going to only have 65% of real capacity. The gauge gets confused because it knows 4.2V is a fully charged cell but its only counted 65% of the coulombs - so it lies to you and gives you its best guess, and it tries to get that capacity number closer to what it thinks it should be as the cell voltage drops.
Secondly the gauge needs a large enough delta in charge to trigger the recalibration and clearly 15% indicated (which may be as high as 40% actual charge) is not enough to get it to learn. Eventually it may learn but it will take weeks of daily shallow charges to get there, or it might not ever get there if the discharge depth is shallow enough.
Remember - the battery charger and the battery gauge are related but not the same thing. No matter how long you put the phone on the charger its not going to put more energy into the battery after its cutoff voltage has been reached. Regardless of what the gauge says, when the battery voltage hits that magic number (typically 4.2V for this chemistry) charging is over and it goes into super-low-trickle mode to keep from overcharging the battery. The gauge doesn't count this super low trickle charge as real charging, so it doesn't correct its internal coulomb count.
But when you do the full discharge to where the cell voltage its its lower software cutoff of 3.5V, the battery gauge learns a more correct value for actual battery charge because it gets to see all of that charge go into the battery. The absolute lower limit for cell damage is low enough that normal phone operation would never see that value (somewhere less than 3.0V).
However if you run your phone dead and then put it in storage dead, it continues to self discharge, even if the phone is off. This is where damage can occur because the battery will continue to loose charge and may reach the point where it literally starts chemically self destructing.
Temperature can aggravate this as well, so you should avoid keeping your cell phone in really hot places (like your car in the summer). If its 38C outside (100F) it might be 20C hotter inside your car and still hotter inside your phone because all that battery power makes hot things even hotter. Once you get to 50C, even fully charged batteries start to get permanently damaged and manufacturers actually recommend storing the battery only partially charged. Remember when I said the new battery only had 40% in it? This is part of the reason.
Back to the Moment - why do people say they need multiple deep discharges to get full battery capacity? Well the clever people in the gas gauge business don't like to see large and dramatic changes in battery capacity so they put limits on how much a battery can change in a learning cycle. So the maximum delta may be 20% or 25% per learning cycle. So subsequent discharge cycles get it closer and closer to the real answer.
So there you have it - my best GUESS as to why the initial battery life from the Moment stinks, but how some lucky people can get 10X the life the unlucky ones get.
I don't work for Sprint, I don't work for Samsung, I don't even make battery powered handheld devices. But I do get aggravated when my brand new bling bling Android phone works worse than my 2.5 year old Motorola Q. I get even more angry when some uninformed person at the Sprint store tries to tell me: "that's just how they are, I get 10 hours out of mine on standby, you're LUCKY to get 12 hours". So I did some digging and took my best guess.
I'm sure somebody may say I'm wrong or I only have it partially right - which is fine, that's why we're all in this forum - to get correct answers and useful information.
But for those of you who are not as nerdy as myself I hope I shed some light on this "issue" and even restored your faith in what seems to be a very nice phone.
Tried doing the "deep discharge" then topped off then powered up the phone...
I have gmail/google apps email being pushed, another IMAP idle being pushed (so background data and autosync are on), GPS off, and made a handful of phone calls and a bunch of text messages. I also receive about 50 emails a day.
Phone ran from 8am to 10pm no problem (went to < 15% around 4pm and 5% around 5pm so there were the associated items being disabled outside of my control).
I wanted to run the battery down a second time so I left it unplugged all night and it was still at 5% in the morning (8am). I receive about 50 emails a night (so total of about 100 in a 24 hour period).
I wanted to run the battery down completely so I opened ConnectBot and initiated an SSH connection and ran "ls" in a while loop. It dropped to 3% almost immediately then shutdown about 5 minutes later.
So, overall, the battery life is pretty good, the gauge just really sucks. Hopefully, this will improve my gauge, especially in light of the previous, detailed post.
I just wanted to make one minor correction from the previous post:
The rating is actually 1440 mAh. It's "milliamp hours" not "milliamps per hour."
So, another way to think about it is, in an ideal sense, if your phone draws 1440mA, the battery will provide 1 hour of power. If your phone draws 720mA, the battery will provide 2 hours of power. If your phone draws 1mA, the battery will provide 1440 hours of power. Of course, the current draw of any electronic device that has user interaction will have a variable current draw.
I have gmail/google apps email being pushed, another IMAP idle being pushed (so background data and autosync are on), GPS off, and made a handful of phone calls and a bunch of text messages. I also receive about 50 emails a day.
Phone ran from 8am to 10pm no problem (went to < 15% around 4pm and 5% around 5pm so there were the associated items being disabled outside of my control).
I wanted to run the battery down a second time so I left it unplugged all night and it was still at 5% in the morning (8am). I receive about 50 emails a night (so total of about 100 in a 24 hour period).
I wanted to run the battery down completely so I opened ConnectBot and initiated an SSH connection and ran "ls" in a while loop. It dropped to 3% almost immediately then shutdown about 5 minutes later.
So, overall, the battery life is pretty good, the gauge just really sucks. Hopefully, this will improve my gauge, especially in light of the previous, detailed post.
I just wanted to make one minor correction from the previous post:
The rating is actually 1440 mAh. It's "milliamp hours" not "milliamps per hour."
So, another way to think about it is, in an ideal sense, if your phone draws 1440mA, the battery will provide 1 hour of power. If your phone draws 720mA, the battery will provide 2 hours of power. If your phone draws 1mA, the battery will provide 1440 hours of power. Of course, the current draw of any electronic device that has user interaction will have a variable current draw.
Guys, I don't understand why all of you don't run out and get this "Battery Left" widget/app from the market place as was suggested by others. Give it a try; it is seriously much better at predicting battery life (in hours and in percentage) than the stock meter/ reported life.
It reports that my battery gets 20 hours to a full charge, (actually, I think the real number is somewhere above that -- 22 or so would be my guess.) It calculates it based on your usage and how your battery meter ticks down.
Its inaccurate at first - but it calibrates itself and tells you how accurate it thinks it is. You need to go through a whole discharge cycle before it is useful.
Seriously.. I highly highly recommend it. "Battery Left by preinvent" Battery Left Widget | Preinvent
I'll just also say that I have NO connection to them at all -- I don't own it, I don't know the author, nothing; I know I sound like a shill for them though.
It reports that my battery gets 20 hours to a full charge, (actually, I think the real number is somewhere above that -- 22 or so would be my guess.) It calculates it based on your usage and how your battery meter ticks down.
Its inaccurate at first - but it calibrates itself and tells you how accurate it thinks it is. You need to go through a whole discharge cycle before it is useful.
Seriously.. I highly highly recommend it. "Battery Left by preinvent" Battery Left Widget | Preinvent
I'll just also say that I have NO connection to them at all -- I don't own it, I don't know the author, nothing; I know I sound like a shill for them though.
Just to report what I am seeing with the battery issue...
Last night was the 2nd night in two days I let my battery go completely dead or at least dead enough so it kept turning itself off. I let it charge all night. When I got up this morning rather than turning it on I connected it to my computer to let it "trickle charge" for a few more hours to help top it off as suggested.
I then powered it on while still connected via USB. When it first started my battery life showed 100% but after a few seconds changed to 90%. I played with it a few more times even connected via the regular charger. Same thing occurs.
Perhaps one more full discharge/recharge cycle might do the trick.
Last night was the 2nd night in two days I let my battery go completely dead or at least dead enough so it kept turning itself off. I let it charge all night. When I got up this morning rather than turning it on I connected it to my computer to let it "trickle charge" for a few more hours to help top it off as suggested.
I then powered it on while still connected via USB. When it first started my battery life showed 100% but after a few seconds changed to 90%. I played with it a few more times even connected via the regular charger. Same thing occurs.
Perhaps one more full discharge/recharge cycle might do the trick.
i'm wondering why the factory reset works with a lot of phones it that there is already too much data to offset the phones initial 'learning' of the voltage curve, so once the battery is working well the phones internal algorithm already has enough data and A. isn't collecting anymore or B. the average is still on the 'wrong' side..
if that makes sense.
if that makes sense.
I've found a lot of helpful stuff in this post, thanks so much to all.
After slogging through quite a few early and more recent pages, I'm wondering if someone can answer me this: If I've already made the mistake of not letting the battery drain a couple times to calibrate the power meter, should I get a replacement battery and start fresh, or is it as effective to do the full power cycles now? I've only had the phone two days.
Thanks so much!
After slogging through quite a few early and more recent pages, I'm wondering if someone can answer me this: If I've already made the mistake of not letting the battery drain a couple times to calibrate the power meter, should I get a replacement battery and start fresh, or is it as effective to do the full power cycles now? I've only had the phone two days.
Thanks so much!
I'm wondering the same... and also if once you have the battery meter calibrated do you have to do anything special to keep it charging the same way?
abrahan
Member
I've done the drain naturally a few times and have found that the battery reacts the same way each time. it gets good for a bit and the ends up the same if not constantly charged.
I charge from midnight to about 7:30 and then I plug it to usb about an hour later at work.
I've done the same. I've fully charged it using top off method, then drained it completely (until the phone turns off by itself and won't turn on for more than 10 seconds). Using the top off method, the phone actually lasts about 30 hours total without a charge under normal usage (ten calls, no long conversations, texts, some e-mail). Under complete heavy usage, (using gps wherever I go, looking up maps, having auto sync on, surfing the web) it will last you about 16 hours, which is about right considering and comparing all the other smart touchscreen phones out there like the iPhone and HTC Touch Pro 2 (with touchflow on). Hope I've helped. Enjoy!
I've done the same. I've fully charged it using top off method, then drained it completely (until the phone turns off by itself and won't turn on for more than 10 seconds). Using the top off method, the phone actually lasts about 30 hours total without a charge under normal usage (ten calls, no long conversations, texts, some e-mail). Under complete heavy usage, (using gps wherever I go, looking up maps, having auto sync on, surfing the web) it will last you about 16 hours, which is about right considering and comparing all the other smart touchscreen phones out there like the iPhone and HTC Touch Pro 2 (with touchflow on). Hope I've helped. Enjoy!
This has also been my experience - about 15-30 hours depending on usage and I didn't start the draining/top off stuff until a few days after (when I found this forum!).
However, the battery meter is still way off for me. Still drops to 80/90% quickly after unplugging it.
I've also downloaded the app referenced above where it learns your usage and displays time remaining and it's still pretty inaccurate also. But, it is still only at 40% accuracy so we'll see how it is once it's at 100%.
Thefoodman52
Android Expert
Shockingly, with my phone, texting variously through the day, browsing youtube between classes, and checking e-mails, games and whatnot, I can end up with the phone lasting from 7:00am to about 11:30am and still be at about 5% battery. I don't know if I got a really good phone, or if I'm an equivalent of a human battery; charging my phone as I hold it. Either way, it lasts all day for me. (Better than my friend's Palm Pre which is almost dead by lunch time. -7:00am-12:10pm with about 14% battery-)
-edit-
My phone stays at 100% for about 45minutes after unplug, then it sticks at 80% most of the day, slowly meandering it's way down to around 30% when I get home and walk in the door.
-edit-
My phone stays at 100% for about 45minutes after unplug, then it sticks at 80% most of the day, slowly meandering it's way down to around 30% when I get home and walk in the door.
how did you do a factory reset?
Thefoodman52
Android Expert
Hey, update. Haven' charged all day, been on it since I got home, and am currently posting from it. It's just saying low battery and its been locked at 5% for the past hour and a half. It does have mmore juice than it leads on to make you believe. Also note, I have cycled the battery twice. =)
evilbeef54
Well-Known Member
Trying it right now, my battery life/meter sucked even after MANY full drains and recharges, however each one seems to be a bit better, the big problem with getting rid of the battery meter I was using is it made a great comm manager allowing you to quickly select gps/wifi/bluetooth off and on instead of having 4 switches, any idea of any other good single comm manager widgets or buttons
Flipper
Guest
I'll second the 'Battery Left' app too. It's awesome for giving a more accurate reading than the native Android battery meter. The developer, Matt, provided some additional details regarding the apps readings. His exact words in an email to me are as follows:
"Accuracy" is a percentage based on the number of readings (I think) the app needs to be really accurate. The app basically logs the time taken to drop between each battery level (eg 100% - 90%, 90% - 80% etc). 100% accuracy means that it has received 5 readings for every battery level change. This value can actually be a bit misleading and I may remove it in a later version as it seems to be causing more confusion that intended!
"Full battery life" is the estimated time taken for a fully charged battery to completely drain. This value will change (a lot to start with) based on your phone usage. As the accuracy % increases, this value should become more reliable and stable.
"Current status" is the hours/minutes left until your battery fully drains.
"Battery percent" is just the battery level as returned by the Android system. This is pretty unreliable really!
"Accurate percent" is the app's estimated % left of the battery.
I also have no connection to the developer. Just one happy user of the app and wanting to give kudos where kudos is due!
"Accuracy" is a percentage based on the number of readings (I think) the app needs to be really accurate. The app basically logs the time taken to drop between each battery level (eg 100% - 90%, 90% - 80% etc). 100% accuracy means that it has received 5 readings for every battery level change. This value can actually be a bit misleading and I may remove it in a later version as it seems to be causing more confusion that intended!
"Full battery life" is the estimated time taken for a fully charged battery to completely drain. This value will change (a lot to start with) based on your phone usage. As the accuracy % increases, this value should become more reliable and stable.
"Current status" is the hours/minutes left until your battery fully drains.
"Battery percent" is just the battery level as returned by the Android system. This is pretty unreliable really!
"Accurate percent" is the app's estimated % left of the battery.
I also have no connection to the developer. Just one happy user of the app and wanting to give kudos where kudos is due!
agent0014
Android Enthusiast
I'd be curious for people to post what their "full battery life" is reported at once the accuracy in this program nears 100%.
Personally I'm getting 74% accuracy and being told that my battery is good for 7 hours and 14 minutes on a complete cycle. This concerns me a bit... I'll report what my readings are once my accuracy is closer to 95-100%. I suspect that I got a battery that isn't doing so well, if there's really a variation in what was produced. Grr.
masbirdies
Well-Known Member
Curious to know what max mV you all are attaining on full chg. I am between.....yes, between 4000-4200. Why can't I just get 4200 all the time?
i reset my battery left app once but now its been on about 3-4 days and i'm @ 75% and seeing 17.5 hours battery life.
weather channel app going, but no GPS following
moxier mail sync every 30 mins
android sync (for gmail/calendar/contacts/etc)
maybe 30-60 mins on phone a day
30-50 texts
varied web browsing.
weather channel app going, but no GPS following
moxier mail sync every 30 mins
android sync (for gmail/calendar/contacts/etc)
maybe 30-60 mins on phone a day
30-50 texts
varied web browsing.
So I tried the full discharge several times. It didn't work for me. I went to sprint to see if they could test the battery. They couldn't at the store in my town but the rep gave me an additional battery at no cost, he didn't even check my account. I was placated but still somewhat upset because I was getting MAYBE 4-5 hours a charge. I had panda home installed, all the nintendo and the genesis emulators (I LOVE THESE), docs to go(paid), screebl lite(Keeps the screen on while you are using the phone, handcent, google voice, aidko book reader (not entirely sure of the spelling) and a few others that I never used. I had task panel x installed which I found more accurate in listing the active processes than others. I would browse the internet maybe 20 minutes a day, play Ghouls and Ghost on my commute into new york 15 minutes each way, send a few texts. I rarely use the phone to actually talk, maybe 10-15 minutes a day if that....................i did a factory reset last night and started charging using the original battery. It came off the charger around 7 this morning. I reinstalled only spare parts and documents to go. Today I talked around 20-30 minutes, sent maybe 6-7 seven texts (usual is anywhere from 20-50), browsed the web for maybe 20 minutes total. It's 11:38 pm here in NJ, a good 16-17 hours later and spare parts says I'm currently at 50%. Tonight I'm reinstalling my emulators and handcent (i'm not going to do a full discharge) and see what the results are. If everything goes well, the next day I will reinstall panda home and see what effect that has on battery life. If the battery life that I got today becomes the standard I will be very pleased with this phone. Given some of the previous posts I suspect the factory reset maybe key if you have done the full discharge and are still getting awful battery life.
I know I said I wasn't but I tried to kill the battery last night. Downloaded the genesis emulator and played ghouls and ghost for about 20-30 minutes and watched a few youtube videos for about 15 minutes. When I was done battery was down to 15 percent. I left the phone off the charger. Woke up 7:30 am and the battery is still at 15 percent. So far 24+ hours without a charge. Won't charge till I get to work.
agent0014
Android Enthusiast
I'm getting awful battery life to the point where I don't have to go through any effort at all to do full discharges before I plug the phone in, and I'm not against doing a hard reset (I'm assuming that's what you mean by a "factory" reset, please correct if I'm wrong). Still... I can't think of any reasonable theories as to why a reset would have any affect on battery life, save for removing processes from apps that cause battery drain, which more than likely are going to get re-installed at some point.
A hard reset causing the battery meter to read more accurately... now that seems more likely (but only slightly). I don't doubt that your battery life is quite improved, but I really wonder what the root cause is. I'm just suspicious... I think it's important to really get to the bottom of the problem. Can anyone think of a reasonable reason (that's not redundant... right?) why a hard reset would improve actual battery life? This whole thing has my brow furrowed a bit.
1. Settings-->sd card & storage---> factory data reset 2. I don't know, I wasn't willing to take that chance. I removed the SD card before I did the reset 3. All my contacts are synced with google so once you sign into your gmail account, it should pull back all your google contacts. I seemed to have lost all my texts messages. (Which is strange, aren't they stored on the sd card?) to Agent0014...I'm not as technically proficient as others here so as to why the reset works...i don't know. It could have also been some of the apps that I had on the phone. I'm doing the trial by fire method. I reloaded Documents to go and the genesis emulator. At midnight battery was still at 50%. After about 30 minutes of ghouls & ghosts and about 10-15 minutes of you tube, the meter dropped to 15%. Didn't put it on the charger. When I woke up this morning it was still at 15%. Didn't charge, played ghouls & ghosts on my commute (about 20 minutes). I've done some internet browsing, sent a few texts and one phone call ( about 5 mintues). It's 11:20 am in NYC right now and battery is still at 15 %. So that's about 28-29 hours since I took it off the charger, almost 12 of those hours the battery is at 15%. I actually want to see how far it will go. After it discharges I'll recharge and reinstall screebl lite and handcent and see if any of those have any effect on battery life. The next cycle I'll reinstall slacker radio and pandora. I never used either when the phone wasn't attatched to the charger so i don't think they were responsible for the crazy battery life i was getting. After that I'll try panda home (similar to open home). Any one here has panda home or open home installed and getting decent battery life? Also I immediately deleted the weather, nfl, and sprint television widgets once rebooting.