Database Users

This is why your battery drops 10-15% in the first 20 minutes.

Plain and simple: When the Evo is fully charged, it begins running off its battery until you plug it back in. It DOES NOT trickle charge whatsoever after it reaches 100%. When you're using your Evo on the charger, and it's showing full 100% charge, it is running off the battery, not the AC plug. And then when you unplug it, well, we all know what happens next. The battery meter drops insanely fast to the actual charge of the battery, which could be very low, depending on how long it's been sitting idle at 100% on your charger.
So all those times you've charged your Evo overnight, only to take it to work the next day and be at 80% within an hour? Your Evo was running off its battery for what I'm guessing was most of the night. It takes my Evo about an hour to two hours to fully charge back to 100%. Let's say you put your Evo on the charger at 11PM, it'll reach full charge by 1AM at the latest, and then run off its battery until whenever you take it off the charger in the morning.
Workarounds?
1) Turn your Evo off while it's charging.
2) If you must leave it on for an alarm clock, put it in airplane mode and end all CPU intensive tasks to minimize battery drain.
3) When you wake up, unplug it for 10-20 minutes (still experimenting with this number), and then plug it back in to top it off. Once it reaches 100%, take it off the charger, and go about your day.
Try it out for yourself. When your Evo is 100% charged, take it off the charger immediately, and I highly doubt you will lose the 10%-15% within minutes. Please share your findings.

Er... Point of note, mine does it even if I pull it off the charger right when it turns green.

Post some technical schematic or other type of proof that shows that this circuitry isn't available in the EVO. That will prove beyond a doubt if what your saying is true.
That being said, only a group of the most retarded electrical engineers would design a charging system as you've described. It is INSANELY easy to build Li-Polymer charging circuitry that does the following (and it pretty much has to do these):
1. Detects battery temperature, and disables charging as a protective measure. In an emergency case it should shut off the device it's powering to allow the battery to cool down. This is a design requirement, or else your house burns down as you dump water on a Lithium fire thinking it's going to put it out. If you have a HERO, you can easily test this. Running the wireless tethering, GPS/Navigation, and Music with the screen running heats up the phone a ton. You'll notice the status light blink green once, then red a couple of times. This means that it's plugged in but not charging. Cool the phone down and it turns solid red again (charging).
2. Disable charging cycle when battery reaches a certain voltage. VERY SIMPLE voltage detection circuitry! The designer can of course adjust a gap to have charging turn back on when it dips below a certain voltage. Usually since this circuitry can be made with a decent amount of precision, that "turn back on" voltage ends up being roughly when the battery discharges to maybe 99.5%. That's just a guess, I admit but there's no harm in having the circuit switch on and off, even if it's often.
There are also a few other circuits that prevent the cell from blowing up in your pocket, like a current sensor to prevent an overcurrent. There's also some stuff that prevents you from being able to discharge the cell below it's avalanche voltage. In case you don't know what that is, when a Li-Ion battery discharges to a certain voltage, it avalanches to 0 (quickly falls). If it hits that point, you've pretty much ruined the battery and it will never charge the same again.
Anyway, this is stuff they taught and had design labs on back in college. While I have no actual proof that the phone wasn't designed as the OP describes, I find it highly unlikely. If this is the behavior that the circuitry exhibits, I would find it easier to believe that it's a design flaw, probably because some idiot didn't compile the correct bill of materials.

I haven't got any schematics or any sort of technical information on the subject. All I know is, it works wonders for me. When I take my Evo off the charger in the morning, it literally drops to ~90% within minutes. Once it does that, if I place it back on the charger for ~20 minutes, it charges back to 100% and stays there for 45 minutes to an hour.
I'd urge anybody who is noticing the immediate 10% to 15% drop in battery to give this a shot.

I would turn it off while I'm charging it overnight, but I use it as my alarm clock

Me Too
I am seeing the exact same behavior as the OP. This is really lame. Because of this, most people will end up losing 10% of their battery every day. Pretty lame.

I charge my phone overnight every night. Never noticed a problem and I just checked my battery and its at 88% and has been off the charger for 2.5hours so I'm not seeing the rapid discharge issue some people are seeing.

I don't think so man, I leave my screen on full brightness while it's charging, and if what you said was true it would go dead on the charger.
I think it's more likely the cells haven’t charged equally, so you get a big initial drop.

Grims said:
I don't think so man, I leave my screen on full brightness while it's charging, and if what you said was true it would go dead on the charger.
I think it's more likely the cells haven’t charged equally, so you get a big initial drop.
Click to expand...
Click to collapse
I'm beginning to think that once the battery reaches 100% full, it runs off the battery until it reaches some arbitrary percentage. At which point it starts charging until it reaches 100% again, and then continues this cycle.
I'm testing a few other things right now. Part of me is convinced it reports 100% charge when it's actually below that level.

Krynj said:
I haven't got any schematics or any sort of technical information on the subject. All I know is, it works wonders for me. When I take my Evo off the charger in the morning, it literally drops to ~90% within minutes. Once it does that, if I place it back on the charger for ~20 minutes, it charges back to 100% and stays there for 45 minutes to an hour.
I'd urge anybody who is noticing the immediate 10% to 15% drop in battery to give this a shot.
Click to expand...
Click to collapse
I'll try this out to see if I can get the same kind of behavior. I guess I honestly haven't looked to see if the phone drops 10-15% after pulling it off.
Krynj said:
I'm beginning to think that once the battery reaches 100% full, it runs off the battery until it reaches some arbitrary percentage. At which point it starts charging until it reaches 100% again, and then continues this cycle.
I'm testing a few other things right now. Part of me is convinced it reports 100% charge when it's actually below that level.
Click to expand...
Click to collapse
This is what should be happening I believe, but I'd be surprised if it was set to such a huge swing like 10-15%
Grims said:
I don't think so man, I leave my screen on full brightness while it's charging, and if what you said was true it would go dead on the charger.
I think it's more likely the cells haven’t charged equally, so you get a big initial drop.
Click to expand...
Click to collapse
This is an interesting theory. I do know that when you have multiple Li-Ion cells in a battery pack, if they discharge unevenly, you have to go off of the lowest charged cell. Again, if a cell were to drop below the avalanche voltage, you'd ruin the pack all together. On the other hand, the circuitry should let ALL cells charge to 100% so it's even again. Maybe they screwed this up, that design isn't so easy! Perhaps it detects one cell as 100% and shuts off the charge. Therefore, one could surmise that if you started with an unevenly charged battery pack, you'd have an immediate decrease in charge to the rating of the lowest charged cell. The good news (maybe) is that this is sometimes implemented with software. That means that HTC could release a bug fix for this, or if we have a savvy dev, they could try to fix it. We just need to prove the theory though.
This is all just a guess, keep that in mind. If I notice something like this with my phone today, maybe I can tear apart the battery and measure the voltage on each cell (if it even has multiple cells). I have a spare, so maybe I'd be up for this. Krynj (or anyone), if you have the HTC Hero, try charging your battery pack with it, see if it exhibits the same behavior on the Hero itself. If it doesn't, then try putting it back into the EVO and see if after a night of charging, it still drops 10-15% after disconnecting it from the AC.

The reason why the battery dies so fast has something to do with the memory card. Charge your phone and take the SD card out and watch it stay at 100% for a long as time. Then do it again with the SD card in and watch it dip down fast.

Apple laptops don't charge unless battery is below 90%. If you plug in the AC and the battery is above 90%, it will just run off AC power but I don't think the battery drains any then.

My battery life has been less than stellar, but I didn't notice it dropping 10-15% instantly off the charger. I did notice that it'd drop about 10% after driving to work with xiialive streaming, which was unusual to me. The battery would start running out after about 9 hours at work. I'd be in the yellow by the time I got home, and the battery would be complaining for a charge in the evening. So that's roughly 12 hours I would be getting out of the phone after normal use.
Since I'm suspecting an issue with the charging circuitry, I just recently tried charging my battery with the Hero. After it was fully charged, I put it back into my EVO last night and haven't charged it since. It's been running 13 hours, and is still nearly full green. The charge is at about 70%. I've been trying to graph the discharge all day too. It only dropped to 87% over night, dropped to 80% when I drove to work (xiialive), and then down to 74% after I spent some time setting up icons and modifying my home screen. This is...hands down a butt ton better than the past week.
I'm not using 4G.
WiFi is off.
3G is on.
GPS is on.
Not running a live wallpaper.
Sync is running at default settings.
Widgets that could be updating constantly:
I have the Clock/Weather HTC widget running.
I have the Dictionary.com "word of the day" widget.
I have the Friendstream Widget running.
Craigslist Craignotifica app is running, set to notify me with search results.
The results are inconclusive though. Yesterday, I wiped and re-flashed DamageControl 3.2.x from scratch (backed up all apps with Ti-Backup, this means Android Market won't be notifying me if there are app updates -grumble-). So, somewhere between re-flashing and also charging my battery with the Hero caused this turn around.

apollooff320 said:
The reason why the battery dies so fast has something to do with the memory card. Charge your phone and take the SD card out and watch it stay at 100% for a long as time. Then do it again with the SD card in and watch it dip down fast.
Click to expand...
Click to collapse
Interesting.....Will have to give a try. Will report back later.

I'm waiting for some definitive results with the "use another charging device or battery" method. It seems that the EVO just sucks at recharging the battery since people who have used another phone or a separate charger seem to report better results.
I leave my phone off at night and charge it - when I turn it on in the morning it still drops 5-10% in the first 20 minutes. But during the day it drops REALLY slow, so I still can get about 13-16 hours before 15% easily.
I have manual account sync, 3g only, wifi at home, usually gps is off, auto backlight settings for screen, and I don't run too many apps in the background, I just use them when I need them.

Has anybody found a solution to this? It's really starting to bother me. I've noticed that I don't seem to have the issue if I charge -> recovery -> wipe battery stats -> reboot. That kind of leads me to believe that something is inaccurate about the battery stats and the phone instead uses the actual raw value provided by the battery instead of whatever it is that it does with the battery stats.

I can tell you this, I bought two of the cheap battery chargers off of ebay and I have two OEM evo batteries. I don't even plug my phone in anymore. I get an hour of standby at 100% from those chargers and it falls instantly when charging from the phone. I just run them down then swap them out. I couldn't be happier and they are only like 10 bucks each with 2 batteries each.
Sent from my PC36100 using XDA App

jnewkirk10 said:
I can tell you this, I bought two of the cheap battery chargers off of ebay and I have two OEM evo batteries. I don't even plug my phone in anymore. I get an hour of standby at 100% from those chargers and it falls instantly when charging from the phone. I just run them down then swap them out. I couldn't be happier and they are only like 10 bucks each with 2 batteries each.
Sent from my PC36100 using XDA App
Click to expand...
Click to collapse
can you post a link or ebay or where ever u bought it from?

Try this I'm doing it from the phone
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250641711190&ssPageName=STRK:MEWNX:IT#ht_1991wt_913
Sent from my PC36100 using XDA App

apollooff320 said:
The reason why the battery dies so fast has something to do with the memory card. Charge your phone and take the SD card out and watch it stay at 100% for a long as time. Then do it again with the SD card in and watch it dip down fast.
Click to expand...
Click to collapse
If you have apps on your sd card that are running then yes that could be the case. SD cards need power to work but I dont know how much they draw..

Prolonged Battery Charging ~ Yes, I believe it is Safe

Prior to getting the Galaxy S, after I read what Samsung were saying in the manual of not to overcharge, I investigated the reasons and wrote in various topics on the battery and the differences between Li-Ion & Li-Pol battery types.
At that point with all the evidence found it made sense to believe that what Samsung were saying in not to overcharge was accurate.
Basically, at that time it was believed the phone used a Li-Pol, Li-Pol batteries are different in that they are 'wet cell' as opposed to Li-Ion which are 'dry cell' charged.
Li-Pol can be manufactured much thinner but can not be manufactured in different shapes.
This is to allow the wet cells whilst under charge which become hot to move around the battery freely. If a Li-Pol was manufactured in different shapes like Li-Ion it would create a 'hot-spot' in an area where the wet cell could not move fluidly around the remainder of the battery.
However, it has now come to light that this is not the case and that the batteries provided with the phone are indeed Li-Ion.
Anyway, moving on to the present.......
After now getting the phone and doing a bit of testing I have found the overcharging issue NOT to be an issue.
When you commence a charge on the phone the icon changes to a charge state.
However, once the battery has reached maximum charge capacity the battery icon automatically changes to a 'Non-Charge' state and then the phone simply runs off it's own battery. This is despite the phone is still connected to the charger.... It's just that the charger although still attached is no longer charging the battery.
As soon as the battery falls below a certain figure (I've had different figures ranging from 98% right down to 91% which is probably due to whatever the phone is doing at that particular time to wake the phone up from realizing "hey, you are still attached to a charger, now wake up and start charging again").
So to all of us who have been worried about overcharging, my personal advise is to NOT worry and charge as and when you feel the need.
Hope this helps.
Beards

Thanks for clear up, I was always been scared while charging that it may blow up.

Nice find!

However, it has now come to light that this is not the case and that the batteries provided with the phone are indeed Li-Ion.
Click to expand...
Click to collapse
When you say "it has come to light", what do you mean? Is it just your deduction from your battery tests, or did you see this info from Samsung?
From what I understood, the LI-Pol overcharging is an issue in theory, but in real life applications its not a problem as long as you use the charger that is designed with LiPol in mind, it will auto shutoff charging once it senses the battery is full.

I have just charged mine from bone empty to full. A notification came up stating that the battery was full and to disconnect the charger. Although the battery monitor app says it is not charging and the normal battery meter has gone solid.
I agree that it seems to stop the charging circuit. Although I thought we were getting LiPo not li ion for these as well it's definitely li ion though.

Morbo66 said:
When you say "it has come to light", what do you mean? Is it just your deduction from your battery tests, or did you see this info from Samsung?
From what I understood, the LI-Pol overcharging is an issue in theory, but in real life applications its not a problem as long as you use the charger that is designed with LiPol in mind, it will auto shutoff charging once it senses the battery is full.
Click to expand...
Click to collapse
Take the battery out and turn it over. Now read the battery type and you will see it says Li-Ion.

if such, it will reduce the re-charge cycle....
i suggest, power off the phone and then keep charge overnight will be safe....
otherwise, if it is on and charges only full then disconnect it

hkfriends said:
if such, it will reduce the re-charge cycle....
i suggest, power off the phone and then keep charge overnight will be safe....
otherwise, if it is on and charges only full then disconnect it
Click to expand...
Click to collapse
Modern battery's don't have cycles where you loose power by continuously topping up the battery.
The practice I use is I charge whenever I get the chance, then after around 30 charges I run it right down and do a full charge.
As to powering off the phone to charge, this is not always convenient.
I need my phone on all the time in case I get an emergency call-out and I'm sure there are others who need their phones on overnight to use as a morning alarm.
Finally, I'm not sure if the practice you mention in powering off the phone and charging overnight would have the same effect in being able to re-charge when the battery level drops.
I think doing it in your method the charger would continuously hit the battery regardless as to whether or not it is fully charged ~ which in effect is what Samsung are saying in not to overcharge.

Beards said:
...once the battery has reached maximum charge capacity the battery icon automatically changes to a 'Non-Charge' state and then the phone simply runs off it's own battery. This is despite the phone is still connected to the charger.... It's just that the charger although still attached is no longer charging the battery.
As soon as the battery falls below a certain figure (I've had different figures ranging from 98% right down to 91% which is probably due to whatever the phone is doing at that particular time to wake the phone up from realizing "hey, you are still attached to a charger, now wake up and start charging again").
Click to expand...
Click to collapse
To me it seems like the phone will NOT use the battery as long as it is plugged in. On my phone the battery meter never drops under 100 % when connected.

Beards said:
Modern battery's don't have cycles where you loose power by continuously topping up the battery.
The practice I use is I charge whenever I get the chance, then after around 30 charges I run it right down and do a full charge.
As to powering off the phone to charge, this is not always convenient.
I need my phone on all the time in case I get an emergency call-out and I'm sure there are others who need their phones on overnight to use as a morning alarm.
Finally, I'm not sure if the practice you mention in powering off the phone and charging overnight would have the same effect in being able to re-charge when the battery level drops.
I think doing it in your method the charger would continuously hit the battery regardless as to whether or not it is fully charged ~ which in effect is what Samsung are saying in not to overcharge.
Click to expand...
Click to collapse
AFAIK, the reason to fully deplete the battery is to properly calibrate the % remaining in your battery. Running your battery down to empty causes more stress to the phone than running it down 50%. I happened to get a free battery with my device, but I would've bought a spare if I didn't get a free one, so I can easily go 3-5 days depending on usage, during this time I have my house and work to do charges. However, let's say I were to be expecting to have less frequent charges, such as taking a vacation, prior to that I would be fully depleting the battery to 0% to calibrate because then the battery level is more important to me. The trade off of long-term life vs short term accuracy is a very easy decision for me to make due to my situation.
In older batteries you had to "use the cells or lose them" situation where it was better, to at least occasionally, completely run down the device rather than doing partial cycles. These days, charging @ 50% 2 times is equivalent to 1 cycle of 100% with less long-term "stress" to the battery.
borchgrevink said:
To me it seems like the phone will NOT use the battery as long as it is plugged in. On my phone the battery meter never drops under 100 % when connected.
Click to expand...
Click to collapse
Same for me.

The reason it tells you to unplug the charger when done charging has nothing to do with battery. It is to save power. Battery chargers still draw some power just because they are plugged in. And in these green times it is ofcourse very popular to have warnings everywhere so you can claim to a green company. And every lithium ion and polymer battery contains electronics designed to protect them from abuse. Including over charging. So that will never be a problem on any phone unless you have a defective battery.

Is there a way to disable the message telling you to unplug the charger? I charge my phone overnight and use it as a clock, but when I wake up in the morning and try to see the time there's this huge popup in the middle of the screen telling me my battery has charged.

Joans said:
Is there a way to disable the message telling you to unplug the charger? I charge my phone overnight and use it as a clock, but when I wake up in the morning and try to see the time there's this huge popup in the middle of the screen telling me my battery has charged.
Click to expand...
Click to collapse
I think I read that the newest, or maybe just a random middle since something has superseded it, firmware fixed this.

interesting topic thx Beards for sharing your insights.

Overcharging - read the manual
Guys, if you will read the manual that came with your SGS, it says there that "DO NOT OVERCHARGE YOUR BATTERY FOR MORE THAN TWO WEEKS". It obviously means that the battery can be overcharged for more than a day as long as it is not more than 2 weeks ( I doubt if someone will be able to do that). So that confirms also that we can recharge anytime and not necessarily have it done to zero before charging. Hope this helps also

i've pretty much quit worrying about the overcharge after the first month of usage
i was following the auto pop up message, just because i wanted to conserve battery
but having 3 spare battery made me though it's futile
and it was extreme annoying to wakeup in the middle of the night, just to unplug it
it was awesome the day i found that patch on the forum to disable the annoying pop up alert that your battery is full.
now i can sleep the whole night without the alert coming online, and rest at ease knowing if the phone actually alerts me, it'll be a phone call or something important, not some annoying "unplug me plz!" message

Your battery gauge is lying to you (and it's not such a bad thing)

I realize that much of this is common knowledge on XDA. Still, every day I see people post about how their phone "loses" 10% as soon as it comes off the charger. I also have friends who can't understand why their battery drains so quickly. Trying to explain this to people without hard numbers is often met with doubt, so I figured that I'd actually plot it out with real data.
So it's not a piece that is optimized for this audience, but I hope that you find it interesting.
--------------------------------------------------
Your Smartphone is Lying to You
(and it's not such a bad thing)
Climbing out of bed, about to start your day, you unplug your new smartphone from its wall charger and quickly check your email. You've left it plugged in overnight, and the battery gauge shows 100%. After a quick shower, you remember that you forgot to send your client a file last night. You pick up your phone again, but the battery gauge now reads 90%. A 10% drop in 10 minutes? The phone must be defective, right?
A common complaint about today's smartphones is their short battery life compared to older cell phones. Years ago, if you accidentally left your charger at home, your phone could still make it through a weeklong vacation with life to spare (I did it more than once). With the newest phones on the market, you might be lucky enough to make it through a weekend.
And why should we expect anything else? Phones used to have a very short list of features: make and receive phone calls. Today we use them for email, web surfing, GPS navigation, photos, video, games, and a host of other tasks. They used to sport tiny displays, while we now have giant touch screens with bright and vibrant colors. All of these features come at a cost: large energy requirements.
Interestingly enough, improvements in battery management technology have compounded the average user's perception of this problem. Older phones were rather inelegant in their charging behavior; usually filling the battery to capacity and then switching to a trickle current to maintain the highest charge possible. This offered the highest usage time in the short-term, but was damaging the battery over the course of ownership. As explained at Battery University, "The time at which the battery stays at [maximum charge] should be as short as possible. Prolonged high voltage promotes corrosion, especially at elevated temperatures."[1]
This is why many new phones will "lose" up to 10% within a few minutes of coming off the charger. The reality is that the battery was only at 100% capacity for a brief moment, after which the battery management system allowed it to slowly dip down to around 90%. Leaving the phone plugged in overnight does not make a difference: the phone only uses the wall current to maintain a partial charge state.
To monitor this, I installed CurrentWidget on my HTC ADR6300 (Droid Incredible), an app that can log how much electric current is being drawn from the battery or received from the charger. Setting it to record log entries every 10 seconds, I have collected a few days worth of data. While many variables are involved (phone hardware, ROM, kernel, etc) and no two devices will perform exactly the same, the trends that I will describe are becoming more common in new phones. This is not just isolated to a single platform or a single manufacturer.
Chart 1 shows system reported battery levels over the course of one night, with the phone plugged in to a charger. Notice that as the battery level approaches 100%, the charging current gradually decreases. After a full charge is reached, wall current is cut completely, with the phone switching back to the battery for all of its power. It isn't until about two hours later that you can see the phone starts receiving wall current again, and even then it is only in brief bursts.
The steep drop in reported battery seen past the 6.5 hour mark shows the phone being unplugged. While the current draw does increase at this point (since the phone is being used), it still cannot account for the reported 6% depletion in 3 minutes. It should also be obvious that maintaining a 100% charge state is impossible given the long spans in which the phone is only operating on battery power.
Using the data from CurrentWidget, however, it is quite easy to project the actual battery state. Starting with the assumption that the first battery percentage reading is accurate, each subsequent point is calculated based on mA draw and time. Chart 2 includes this projection.
Now we can see that the 6% drop after unplugging is simply the battery gauge catching up with reality.
The phone manufacturers essentially have three choices:
1. Use older charging styles which actually maintain a full battery, thereby decreasing its eventual life
2. Use new charging methods and have an accurate battery gauge
3. Use new charging methods and have the inaccurate battery gauge
Option one has clearly fallen out of favor as it prematurely wears devices. Option two, while being honest, would most likely be met with many complaints. After all, how many people want to see their phone draining down to 90% while it is still plugged in? Option three therefore offers an odd compromise. Maybe phone companies think that users will be less likely to worry about a quick drop off the charger than they will worry about a "defective" charger that doesn't keep their phone at 100% while plugged in.
Bump It. Or Should You?
One technique that has gained popularity in the user community is "bump charging." To bump charge a device, turn it off completely, and plug it into a charger. Wait until the indicator light shows a full charge (on the ADR6300, for example, the charging LED changes from amber to green) but do not yet turn the device back on. Instead, disconnect and immediately reconnect the power cord. The device will now accept more charge before saying it is full. This disconnect/reconnect process can be repeated multiple times, each time squeezing just a little bit more into the battery. Does it work?
The following chart plots battery depletion after the device has received a hefty bump charge (6 cycles) and then turned on to use battery power. Note that the system does not show the battery dropping from 100% until well over an hour of unplugged use, at which point it starts to steadily decline. Again, however, it should be obvious that the battery gauge is not syncing up with reality. How could the rate of depletion be increasing over the first 5 hours while the rate of current draw is relatively steady? And why does the projected battery line separate from the reported levels, but then exactly mirror the later rises and falls?
The answer, of course, is that bump charging definitely works. Rather than anchoring our projected values to the first data point of 100%, what happens if we anchor against a later point in the plot?
Aligning the data suggests that a heavy bump charge increases initial capacity by approximately 15%. Note that the only other time that the lines separate in this graph was once again when the phone was put on the charger and topped up to 100%. Just as with the first set of graphs, the phone kept reporting 100% until it was unplugged, dropped rapidly, and again caught up with our projections.
So what does it all mean?
If you absolutely need the highest capacity on a device like this, you will need to bump charge. There are currently people experimenting with "fixes" for this, but I have yet to see one that works. Be warned, however, that repeated bump charging will wear your battery faster and begin to reduce its capacity. If you are a "power user" who will buy a new battery a few months from now anyway, this presumably isn't a concern. If you are an average consumer who uses a device for a few years, I would recommend that you stay away from bump charging. The bottom line is that you don't really "need" to do it unless you are actually depleting your battery to 0% on a regular basis.
If you are someone who can top off your phone on a regular basis, do it. Plug it in when you're at home. Plug it in when you're at your desk. As explained by Battery University, "Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory."[2]
Beyond that, the best advice I can offer is to stop paying such close attention to your battery gauge and to just use your phone. Charge it whenever you can, and then stop obsessing over the exact numbers. If you really need more usage time, buy an extended-capacity battery and use it normally.

Pretty nice to know why it drops from 100% so fast now .....THANKS!
Sent from my ADR6300 using XDA App

Well written ..even prior to the data presentation!

Are the images not posted or am I doing something wrong?

Great read, well thought out and explained.
The only thing I'll add is that while there isn't a "memory affect" on our batteries, it is still recommended to do a full charge/discharge (don't let it get to <5% though) about once every 3 months.

Thanks for the kind words, gents.
spatton said:
Are the images not posted or am I doing something wrong?
Click to expand...
Click to collapse
You should be able to see them embedded in the post. You can try reading it directly from my site: http://byrong.com/PowerTesting/
I'm not currently aware of any issues with my hosting, so hopefully it shows up OK for people.
toosurreal01 said:
The only thing I'll add is that while there isn't a "memory affect" on our batteries, it is still recommended to do a full charge/discharge (don't let it get to <5% though) about once every 3 months.
Click to expand...
Click to collapse
Good point for many devices which may learn the wrong battery stats if they are never depleted. I am still not sure how this may or may not apply to our devices, so I hesitate to comment on it one way or the other.
I hope someone takes the time to delve more deeply into the battery stats that our devices record. Given the fact that we can wipe them using clockwork recovery, we are at least aware of where/how they are being kept.
That brings up another point worth mentioning, by the way: some people claim that wiping battery stats after a bump charge is a "fix" to increase the total charge that our phones will later apply. This has not been my experience. I have bumped/wiped in accordance with the various tutorials out there, but even afterward I have still found a large difference between a subsequent bump-charging and regular charging.

For some reason, my employer does not like your site and as such, I could not see he images.
Thanks for taking the time to do this. You confirmed my suspicions that I never documented but certainly experienced.
My take on the battery thing now, especially after reading this:
Actively and aggressively seek chargers
Don't look at he specific % of battery, when it gets yellow, get more aggressive
Relax
Use it in the morning, charge it while you shower - better than running out the door.
Great article!

I used to bump charge now if I'm near a charger I just throw it on for a few minutes. I also always carry a spare battery on me.
Sent from my Incredible using XDA App

Very nice.
I have a couple questions though. So on older phones, leaving it plugged in and it hit 100%, but was still getting full current from the charger for the remainder of the night, damages the battery right? so bump charging is doing the same thing, but not really damaging it as much, becuase we're unplugging it as soon as the light turns green, so its "at 100%" but we arent leaving it plugged in for hours after its green.

Excellent read. Very informative and well written!!

very well written. thank you, sir

spatton said:
For some reason, my employer does not like your site and as such, I could not see he images.
Click to expand...
Click to collapse
Wow, I'm a little flattered. This is the first time I've heard of an employer blocking my site.
ufvj217 said:
So on older phones, leaving it plugged in and it hit 100%, but was still getting full current from the charger for the remainder of the night, damages the battery right?
Click to expand...
Click to collapse
I don't have hard data for my older devices like I do for this phone, so my answers to this (and your following questions) are a mixture of anecdote, reading, and conjecture.
I don't think that the older devices were still getting full current after hitting 100% but rather some sort of trickle charge to keep them topped off. Battery chemistry itself will limit the charging current that can be applied as the battery approaches capacity.
Depending on the device and its management system, damage could come from too much charge being applied, or it could simply come from keeping the battery at the highest charge level possible for prolonged periods. That may sound like the same thing, but technically it's not.
Batteries are wear items, and even use under ideal conditions will eventually kill them. As shown on Battery University's page on prolonging lithium-based batteries, however, even minor decreases in the final charge level will greatly increase the number of cycles that a battery can endure (note figure 2)
ufvj217 said:
so bump charging is doing the same thing, but not really damaging it as much, becuase we're unplugging it as soon as the light turns green, so its "at 100%" but we arent leaving it plugged in for hours after its green.
Click to expand...
Click to collapse
I'm not 100% sure whether:
Bump-charging is simply charging the battery to its physical capacity, which is greater than the capacity that our software thinks is appropriate;
Bump-charging is actually applying a charge to the battery that is outside of the rated specs for the battery; or
Some mix of 1 & 2
Also, since I can't use any logging tools while the phone is off, I'm not sure how the current behaves once the phone hits 'green' while off.
I therefore don't want to make a hard guess at the three options listed, as I don't want to spread false information. With that said, I think it is apparent through both testing and real-world use that bump-charging applies a charge that is higher than what is allowed when all of the phone's protections are "awake." Given that, we have to ask ourselves why the waking protections are stricter.
If you are inclined to believe that the manufacturer is setting limits that are too low, in an effort to prolong cycle life (or limit liability), then maybe bump-charging isn't too bad.
If you are inclined to believe that the manufacturer chose the charging limits for a good reason, and has the best interest of the consumer in mind, then bump-charging should be considered problematic.
I don't know if one of these is absolutely true over the other, but my life is easier without bump-charging, so I just avoid it. That's a personal choice though. I'm not trying to advance a position here as much as I'm trying to spread information and spark discussion.
Thanks to everyone for taking the time to read, and for your questions and comments.

Well put. I rarely bump charge myself, sometimes once i get to work (its at 88-90% by this time, 7am) ill charge it back up, then power it off and bump charge it a couple times. depending on what ill be doing that day after work. since im at a desk though all day, i usually just use it, when it gets to about 50 or so, ill plug it back in, etc. that seems to work fine for me. i do have the htc 2150 battery as well

Like you said, most people probably knew most of that, but still great to see it well written and explained.
Great job on this, I'll most definitely be passing it along to people who ask me what's going on.
Again, well written and very well explained.
Thanks

Thank you!
This has been perplexing me for some time now. Thanks for the info!

Well if youre looking for a batt fix that fixes this issue, you have to take a look in the Nexus and Desire forums. The Desire has it working for sure and I'm not sure about the Nexus. Unfortunately, their fix cannot be applied to our phones because we use a different battery driver...>.< sucks.
And bump charging works sometimes, idk why people turn off their phone to bump charge, thats actually worse than bump charging it when the phone is on. Bump charging when the phone is on is the best thing, the reason why is because percentage means actually nothing with these phones. THe percentage is read from the batterystats.bin file (I think..), which can easily be manipulated. Bump charging works because it rewrites that file once it hits 100% and at the same time, charges back to the highest voltage possible.
I've been working on a fix for our phones (i personally dont own an Incredible, I own an Evo and they use the same driver) and I'm pretty much close. Been on it 24/7 for the past few weeks and all I have to deal with now is the charger timer that seems to reset at a certain time that I cant seem to find yet. This fix should also calibrate the battery on each charge so that you will no longer need to wipe stats or bump charge or do any of that stuff.

so you can charge with the phone on until the led is green, unplug, plug back in (with phone still on) and itll change back to amber for a while?

ufvj217 said:
so you can charge with the phone on until the led is green, unplug, plug back in (with phone still on) and itll change back to amber for a while?
Click to expand...
Click to collapse
if you unplug and plug back in instantly it wont do jack for ya. You gotta unplug, wait until you hit 99% and then plug it back in and wait for 100%. Doing that while the phone is on is best because if you've ever noticed, the batterystats gets messed up while the phone is off for the most part (ex: Recovery mode and stuff). Also, idk if this is true for the Inc, but with the Evo, if you have the phone on the charger while its off and power it on while the LED is green, it doesnt stay charging, it goes off the charger to use some battery to power on and then it charges and that messes with the batterystats which messes with the voltage for some odd reason.

Very nicely done. There are always going to be people who don't get it, but this is easily the best synopsis I've seen yet. People get all wrapped up in numbers, instead of actual use, and the percentage becomes way more important than it should be. Just do whatever you need to do (keep a charger handy, get a bigger battery) to support your needs.
I'm one of the fortunate ones... between the tweaks I've done with custom kernels and whatnot and the fact that I'm not a real heavy user, I have no problem making it from morning to bedtime with more than 50% remaining. And you know what? I don't care whether my phone's at 70% or 10% when I plug it in before bed. As long as it makes it that far, I'm happy. I could easily go two days between charges, but I don't bother, because there really isn't any point other than to gloat about my great battery life, which doesn't impress anyone. I've got a charger, and I use it every night. It works for me.

One of the best posts i ever read here! Kudos from an electrical engineer

Battery Calibration process

Is this the definitive way to do it?
http://hemorrdroids.net/battery-calibration/
Those steps came from here, xda devs.
1. Run the device down until it turns itself off.
2. Turn it back on and wait for it to turn itself off again.
3. Remove the battery for 10 seconds.
4. Replace the battery, but leave the device off.
5. Charge the device until full and then for another hour.
6 **Root users only** Using a Terminal Emulator, type “su” enter, followed by “rm /data/system/batterystats.bin”
7. Run the device’s battery down until it turns itself off.
8 .Turn the device on and charge for at least 8 hours.
9. Unplug the device, turn off, then charge for another hour.
10. Unplug the device, turn on, wait 2 minutes.
11.Turn off again and charge for another hour.
12. Restart and use as normal.
Quite a performance! Does it preserve battery lifespan, or is it more to do with slowing down battery drain and does it really work?
He mentions 2 interesting things:
"Generally charge them before they get lower than 50%". I didn't know that, so it's actually better to charge more often and not let it drain down?
"USB charging is actually better for the battery and you may get up to 1 hours more standby time." So you gain an hour standby but it takes twice as long to charge the phone.

Nice manual
Will try it
Sent from my GT-I9100 using Tapatalk

Some will say that its complete nonsense .
Overcharge for 8 hours ??? how does the battery not turn charging off at 100%
Recharge 50% the accepted figure is not to go below 20% to often .
They may be right or wrong their are so many contrasting views on battery charging .
jje

Discharging battery and then reloading it fully, it's the normal procedure for battery calibration for almost all the devices in the world (including computers, etc.).
Step 8 to 11 seems quite a bit strange however.

hm, just seen a different way to calibrate the battery. basically, you drain the battery, take it out for a couple of minutes, put back in, then try to turn it on to make sure it's completely flat.
then you charge it fully, then boot to recovery and wipe battery stats then drain and fully charge. so... which one is more likely to be the better?

that guy also advises to repeat that 12 step, 1-2 day long tedious procedure "every month or so".
it is lunacy honestly speaking

does it work? did he died ?

LOL I dont understand .... I just read in another day that NEVER LET BATTERY GO LOWER THAN 15% and know I read "drain drain drain" Oh welll ...
I also thought that at 100% the charging process stops.

Although this thread is about battery calibration, these questions about battery charging always pop up.
Battery calibration is the process by which you set your device with your battery data.
Every single battery is slightly different. Although there are minimum stantards to every spec of the battery, each battery is different.
Calibrating your battery is nothing more than setting your phone to the real specs of your own battery (since the phone comes configured with the battery factory standards). For example, your phone may be set to use a battery which maximum charge is 1650 mAh, but your battery has a maximum charge of 1625 mAh. That may be within the acceptable factory standard, meaning you have a normal battery, but that also means that your phone will never indicate a 100% charge after you unplug the charger.
If you calibrate that hypothetical battery, you will "tell" your phone that its maximum charge capacity is actually 1625 mAh, meaning from that on your phone's battery indicator will be more accurate.
For that reason, it is necessary to fully discharge and fully recharge your battery for the calibration process, since your device must read the actual specs (minimum charge, maximum charge, charging current, etc) of the installed battery.
I don't know about how many times this full cicle (discharging and recharging) must be performed, but that is the reason why it must be performed for the calibration to succed.
A DIFFERENT THING is the normal discharging and charging process during normal use of the phone.
In this case, you should NEVER let your battery go under 20% and, what few people know, it also should never go over 95%. This stresses the battery and diminish its life time.
Also, and there's a lot of doubts about this, the lower the charging voltage, the slower the charging process, but the longer the battery life.
High charging voltages (like the one used by the charger sold with the phone, which is around 5V) stress the battery, diminishing considerably its life time.
That is true for all lithium-ion batteries!
Therefore it is better to charge your phone through USB (which uses around 4,3V) than to do it using the charger provided with the phone.
You may be asking "If the charging voltage of the charger provided by the manufacturer stresses the battery, why does the manufacturer provide such charger?"
For purely commercial reasons! Higher voltages mean shorter charging cycles, which please the consummer. Moreover, the battery capacity loss with the factory provided charger is around 15-20% a year (considering "normal" to "heavy" use). That is to say that after a year your battery will only reach 80-85% of the maximum charge it used to reach when it was new. And by that time your manufacturer expects you to consider buying a new phone, with more features.
Summing it up:
- calibration is just the process by which you "tell" your phone what the real specs of your battery;
- in normal use, charging your phone through USB is better than doing it with the manufacturer provided charger;
- try not to let your battery charge go under 20% nor above 95%;
- if you're interested, read more about it at batteryuniversity.com

Spin three times in clockwise direction with left middle finger on your nose while blinking your eyes with the phone plugged in.
Jump in the air 3 times.
Unplug phone.

Thats some messed up instructions.
Do you have any idea what kind of strain you're putting on the battery while doing all that?
All you're gonna get is some extra minutes, maybe an hour but is it really worth it because you're just reducing overall battery lifespan by doing that procedure over and over.
Specially when you constantly keep the battery at 4200mV (full charge) for a long time. You're practically killing it by overcharging.
Transmitted from a Galaxy far far away via XDA telepathy.

m2smoe said:
Spin three times in clockwise direction with left middle finger on your nose while blinking your eyes with the phone plugged in.
Jump in the air 3 times.
Unplug phone.
Click to expand...
Click to collapse
that made me chuckle

Never done a calibration on a battery and most of the time i even didn't let battery to discarge very much and then load it again. Never had a problem with battery life it last how long it should last every time and i've used that battery for years. So the battery "calibration" are kinda useless.

Matriak31 said:
that made me chuckle
Click to expand...
Click to collapse
Well then, my job here is done

m2smoe said:
Well then, my job here is done
Click to expand...
Click to collapse
it is indeed...i should follow you just to have more laughs like that cheers

RenatoN said:
Although this thread is about battery calibration, these questions about battery charging always pop up.
Battery calibration is the process by which you set your device with your battery data.
Every single battery is slightly different. Although there are minimum stantards to every spec of the battery, each battery is different.
Calibrating your battery is nothing more than setting your phone to the real specs of your own battery (since the phone comes configured with the battery factory standards). For example, your phone may be set to use a battery which maximum charge is 1650 mAh, but your battery has a maximum charge of 1625 mAh. That may be within the acceptable factory standard, meaning you have a normal battery, but that also means that your phone will never indicate a 100% charge after you unplug the charger.
If you calibrate that hypothetical battery, you will "tell" your phone that its maximum charge capacity is actually 1625 mAh, meaning from that on your phone's battery indicator will be more accurate.
For that reason, it is necessary to fully discharge and fully recharge your battery for the calibration process, since your device must read the actual specs (minimum charge, maximum charge, charging current, etc) of the installed battery.
I don't know about how many times this full cicle (discharging and recharging) must be performed, but that is the reason why it must be performed for the calibration to succed.
A DIFFERENT THING is the normal discharging and charging process during normal use of the phone.
In this case, you should NEVER let your battery go under 20% and, what few people know, it also should never go over 95%. This stresses the battery and diminish its life time.
Also, and there's a lot of doubts about this, the lower the charging voltage, the slower the charging process, but the longer the battery life.
High charging voltages (like the one used by the charger sold with the phone, which is around 5V) stress the battery, diminishing considerably its life time.
That is true for all lithium-ion batteries!
Therefore it is better to charge your phone through USB (which uses around 4,3V) than to do it using the charger provided with the phone.
You may be asking "If the charging voltage of the charger provided by the manufacturer stresses the battery, why does the manufacturer provide such charger?"
For purely commercial reasons! Higher voltages mean shorter charging cycles, which please the consummer. Moreover, the battery capacity loss with the factory provided charger is around 15-20% a year (considering "normal" to "heavy" use). That is to say that after a year your battery will only reach 80-85% of the maximum charge it used to reach when it was new. And by that time your manufacturer expects you to consider buying a new phone, with more features.
Summing it up:
- calibration is just the process by which you "tell" your phone what the real specs of your battery;
- in normal use, charging your phone through USB is better than doing it with the manufacturer provided charger;
- try not to let your battery charge go under 20% nor above 95%;
- if you're interested, read more about it at batteryuniversity.com
Click to expand...
Click to collapse
You should post the source for your info, cause I am seeing a lot of incorrect information in here.
If you guys want to learn about your battery, visit the site Battery University

The OEM replacement battery is worth about $10.
Save yourself the stress....use it...charge it when you need to...if the battery ever fails cough up $10.
Sent from my GT-I9100 using XDA App

The way I would calibrate my batteries is a bit different. Lithium ion batteries don't need to be drained then charged to full AFAIK, and I even remember reading somewhere that draining it is actually only for NiCad batteries. It used to be relevant when phones were using NiCad but not anymore.
Read: http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
As such I have read that the universal way to 'calibrate' batteries is by charging to full, using for a couple of mins and charging again.
What I have been doing is:
1. Charge to full when phone is switched off (doesn't matter if it's from 0% or 99%).
2. Switch on the phone, use for 5 mins.
3. Switch off then charge until full.
4. Repeat step 2 once more
That's it! It seems pretty simple but it seems to have worked for me.

The way i do it is different. Firstly i have the battery calibration app from the market by Nema..then i fully charge my phone and when it says its fully charge i go into the app. There it gives me the instructions on how to calibrate...First i wait till i charge the phone without any interruptions. then click on the app and wait til the battery goes to 4200MV and then i press the calibrate button and then the app does it for me. Then i drain the battery again without any interuptions or breaks during that time and then charge it again once battery dies down and thats it.
there are so many ways being touted on the forums you really dont know which one to go for...but whatever works for each person then who are we to tell someone different just thought i share that

If my battery dies, or gets significally lower capacity after 1 or 2 years of usage, I'll just buy a new one if I plan to keep the phone longer.. Going through these rituals and painstakenly monitor my battery % so that it never goes below 20 % or above 95 % is just not worth it.. Doesn't increase the life THAT much anyway.. I use the phone until I hear the beep for low batt, and from there until I have a charger available.. Most of the time it's before it reaches 10 %, thats good enough for me.. Once in a while it might even go so far that it dies.. Then I charge it till it says 100 %.. Most of the times I plug it when going to bed, and let it charge over night.. This is normal usage and what the battery should be designed to handle, and so far it does..

New battery, how to "initialize" it?

Hi everyone, i've ordered a new battery (Polarcell 2900mah) and i should receive it this week...i saw somewhere that android does not really read the battery percentage, but instead estimate it. I also read about battery recalibration or initialization which is fundamental for android to proper estimate the actual power contained in the battery, but i'm a little bit confused anyway...since i want my new battery to work proper and last as long as it could, do someone among you know about this fact? Is there any guide? I can't find anything.
P.S. i have a I9505 (jfltexx) and i'm actually on RR v5.6.3...so android 6.0.1

That is complete BS.
I never "calibrated" mine.
PS: most calibration apps do the same thing, and that is to delete a file that has no connection with the battery percentage. This was stated by a Google engineer.
Batteries should come charged at 50%
That's the perfect storage charge.
If there was any calibration method, then it would be: let it discharge completely, then recharge it to 100%.
Another note, valid for Li-on batteries: The deeper the discharge the shorter its life will be. In other words, if you let it discharge as low as 20%, or lower, every day, the battery life (before it needs replacing again) will be shorter.
Another thing: Leaving the battery at 100% charge for extended periods can also damage its ability to hold a charge for a longer time.

GDReaper said:
That is complete BS.
I never "calibrated" mine.
PS: most calibration apps do the same thing, and that is to delete a file that has no connection with the battery percentage. This was stated by a Google engineer.
Batteries should come charged at 50%
That's the perfect storage charge.
If there was any calibration method, then it would be: let it discharge completely, then recharge it to 100%.
Another note, valid for Li-on batteries: The deeper the discharge the shorter its life will be. In other words, if you let it discharge as low as 20%, or lower, every day, the battery life (before it needs replacing again) will be shorter.
Another thing: Leaving the battery at 100% charge for extended periods can also damage its ability to hold a charge for a longer time.
Click to expand...
Click to collapse
I'm not talking about fabulous apps which do magic things...i mean, as i read, there should be some cycles of charge and discharge which nave to be done, not for the battery, but for android, in order to really manage the power in the battery, without those 20% from 100% to 80% dropping like stones. Sorry for my bad english, i hope i explained myself.

Guarino95 said:
I'm not talking about fabulous apps which do magic things...i mean, as i read, there should be some cycles of charge and discharge which nave to be done, not for the battery, but for android, in order to really manage the power in the battery, without those 20% from 100% to 80% dropping like stones. Sorry for my bad english, i hope i explained myself.
Click to expand...
Click to collapse
No it's complete crap. Android does that perfectly fine. There is really nothing you need to do.
That only applied to phones 4 years ago. You never need to calibrate it anymore.

Guarino95 said:
I'm not talking about fabulous apps which do magic things...i mean, as i read, there should be some cycles of charge and discharge which nave to be done, not for the battery, but for android, in order to really manage the power in the battery, without those 20% from 100% to 80% dropping like stones. Sorry for my bad english, i hope i explained myself.
Click to expand...
Click to collapse
As I said, I never calibrated mine and it works.
That whole "Let it discharge completely and then charge it over night" is just a left-over from the old batteries. Those new kind of batteries don't need that.
Those batteries aren't ment to stay at full charge all the time. That is the reason for the fast drop. Mine drops for 100% to 99% in the first 5 minutes. And it drops like that until it stabilizes at around 94%.
The moment your battery needs calibration is when the phone shows 30% left and it suddenly turns off. That means it shows a wrong percentage, or that the battery needs to be replaced.

OK, then i'll just swap that battery and use the phone normally...thank you all

lithium batteries don't want to be left fully charged or fully discharged for too long. it damages the poles if that's the right way to say it. so outside of that just follow what your new battery makers recommendations