I've been seeing "Battery Calibration" a lot lately especially with custom Roms and how to improve battery life. Here is great info on prolonging battery life for your epic. And what NOT TO DO!
Forgive me if this is in the wrong section of the forum but I saw a lot here on this topic so I thought I would share the information I have.
Lithium Ion batteries DO NOT NEED TO BE CALIBRATED. Forgive me for yelling but I can't stress it enough. The current lithium ion batteries for your computer and most of all, your Samsung Epic4g do not have an internal memory. All they have is an internal chip that prevents them from overcharging, and of course the cells for the Lithium Ion process to occur.
Nickel Cadmium or NiCad batteries do have an internal memory that acts much like a fuel gauge in your vehicle, it tells the battery small information on % charge etc.
Your Samsung Epic 4G has to interpret the amount of charge left and % from your battery. That's why it saves battery stats. It really works by averages and the only thing the battery tells the phone is "I'm Full!" when it reaches 100%. or "I'm Dead!" when the cells are empty. Your phone does the rest and interprets to you in % how much life is left in that battery.
Someone got the not so bright idea of calibrating the battery, maybe because it worked on a NiCad battery, maybe it should work on a Lithium Ion battery? WRONG!
Lithium Ion batteries have a prescribed life. The average life of a 1500mAh battery is around 2000-3000 charges. The reason behind this is the Lithium Cells become unstable and are prone to explosion.
So, every time you fully discharge your battery and recharge it, you just shortened the overall life of your battery. And if you're one of those people who discharge and recharges 3 times consecutively, you're really messing up your battery. Heat is the biggest enemy of Lithium Ion Batteries, if they get too hot, from forced discharges they actually develop tiny crystals on the inside of the cells that prevent it from being truly 100% charged.
So, in reality your phone is telling you your battery is 100% charged when it is only 85% fully charged inside the battery.
Please, please, please, do not discharge your battery and consecutively recharge it again. I love my epic and I hate to see other epics abused like that.
If you want to prolong your battery life follow these short and simple steps:
1. The closer you keep your phone to 100% the longer it will live.
2. Avoid unnecessary discharges to 0%.
3. Charge your phone when it is off, not in standby. - Charging in standby causes unwanted heat.
4. Unplug your battery when it's fully charged. - Sure, that "Battery 100% Full" message is annoying, but maybe it was put there for a reason? Hmm.
5. Wipe your battery stats weekly, only after a full power off charge, or Rom Change
6. Avoid doing anything that heats up your phone. - Sure WiFi Tethering and BlueTooth Tethering is awesome, but it heats up the phone in most cases, this will destroy your battery.
I can't post the link because I don't have enough posts. But go to google , search "battery university" and then look for lithium ion batteries.
I am a computer science / electrical engineer and I have done extensive research in batteries and mobile devices.
Please save those batteries!
-George
Interesting post. Thanks!
Sent from my Emotionlessly Bonsai'd Epic 4g.
A cycle is a cycle friend, whether dropping to 50% twice or dropping to 0% once ... it is still a registered cycle. Below is the best write up I have came across concerning battery care. Still trying to figure out the purpose of this thread however, if you are insinuating that a batt stat reset and full charge to discharge is not helpfull after a kernel change (voltage change) then you are sorely mistaken, it WILL, I repeat WILL cause your device to not register the true charge state of your battery unless you do so. And if your phone is not monitoring your battery correctly it could negate symbiance between your batt and your device.
Wiping your stats without a full discharge is useless btw. In the fact that one of the few things your post was accurate on is that the only two way communications between battery and device happen at full and empty. Would probably do a lot of good if this thread wrought with misinformation was deleted. Just in case it is not a really good caresheet is as follows.
============================
Lithium Ion Battery Care
Batteries are made to be used, so use them.
Just like couch potatoes, batteries need exercise. The chemicals in Lithium-Ion batteries respond best to regular recharging. So if you have a laptop, don’t keep it plugged in all the time; go ahead and let it drain to about 40 or 50 percent of capacity, and then recharge your computer.
The life of a Lithium-Ion battery can be measured in charge cycles. A charge cycle occurs when 100% of a battery’s capacity is used. Let’s say you use 50% of your laptop’s battery one day, charge it overnight, and then you use 50% of the battery again the next day. Even after charging it back up again, you’ll have only had one charge cycle occur. Most laptop batteries are rated for a useful life of at least 300-500 charge cycles, but high-quality, properly maintained batteries can retain up to 80% of their original life, even after 300 cycles.
Periodically calibrate your battery.
Most batteries that have a “fuel gauge”, like those in laptops, should be periodically discharged to zero. This can be accomplished simply by letting your computer run until it reports a low-battery state and suspends itself. (Do not let your computer deep discharge, as I’ll explain in the next item.)
The gauge that measures the remaining power in your laptop is based on circuitry integrated into the battery that approximates the effectiveness of the battery’s chemical compounds. Over time, a discrepancy can develop between the capacity that the internal circuitry expects the battery to have and what the battery can actually provide. Letting your computer run down to zero every month or so can recalibrate the battery’s circuitry, and keep your computer’s estimates of its remaining life accurate.
Don’t practice so-called deep discharges.
Most laptops will suspend operation if the battery drains too low. Even if your computer goes to sleep, though, most batteries that are in good working order will still have a reserve charge available. This reserve will hold the computer’s working memory in state for a little while. A deep discharge has occurred when even that percentage of reserve power is used up. The computer will have turned off completely, and sometimes you’ll notice that it will have lost track of the correct date and time. Deep discharges will strain your batteries, so try to charge them frequently.
Avoid exposing your battery to heat (when possible).
Heat can overexcite the chemicals in your battery, shortening its overall lifespan. In fact, it’s been speculated that the biggest cause of early battery expiration is the heat that batteries can be exposed to when they’re stored in computers that are running off AC power. Laptops — especially modern multi-core machines — can get very hot when they’re plugged in, easily over 100 degrees Fahrenheit. That’s hot enough that extended exposure will negatively affect your battery. If you want to be really protective, there’s nothing saying that you can’t pop the battery out of your laptop if you’re going to be within reach of a power outlet for a while.
There may be times that you can’t help but expose your laptop battery to heat; you may live in a warm climate, for instance. You can, however, try and avoid exacerbating the issue. Make sure your laptop is well ventilated and that you’re not operating it on a surface that retains heat, even when you’re not plugged into mains power.
Store your batteries properly.
If your laptop or portable device isn’t going to be used for a while, you should remove its Lithium-Ion battery, if possible. Even if the battery can’t be separated from the device, it should be stored in a cool environment at about one-half charge. Cool temperature is recommended by experts because that can slow the natural discharge that batteries will undergo even when they’re disconnected from their device.
I’ve seen some people go even further and recommend that spare batteries be stored in the refrigerator. I don’t think this is a very good idea; I’m concerned about condensation that might build up. Don’t put your batteries on ice, but keep them out of the sun.
Ultimately, I believe that buying spare Li-Ion batteries is a losing game, because the batteries start degrading as soon as they’re manufactured. Usually those spare batteries spend most of their time sitting in a charger, losing useful life. If you need to be really mobile, you’re better off purchasing an adapter cable you can use with the power sources available in planes, trains, or autos. And, of course, by taking good care of the battery you already have."
One question in regards to your post. I currently use the desk top cradle to plug in when I get home, will this mess with the battery too? It was made by Samsung I am confused as to why they would make something to use with your epic if it will hurt the battery.
HeisRisen said:
A cycle is a cycle friend, whether dropping to 50% twice or dropping to 0% once ... it is still a registered cycle. Below is the best write up I have came across concerning battery care. Still trying to figure out the purpose of this thread however, if you are insinuating that a batt stat reset and full charge to discharge is not helpfull after a kernel change (voltage change) then you are sorely mistaken, it WILL, I repeat WILL cause your device to not register the true charge state of your battery unless you do so. And if your phone is not monitoring your battery correctly it could negate symbiance between your batt and your device.
Wiping your stats without a full discharge is useless btw. In the fact that one of the few things your post was accurate on is that the only two way communications between battery and device happen at full and empty. Would probably do a lot of good if this thread wrought with misinformation was deleted. Just in case it is not a really good caresheet is as follows."
Click to expand...
Click to collapse
Don't quite know if you're trying to "one-up" me on battery life, but this post is not misinformation, I am trying to explain in layman's terms on how a battery communicates with the phone. I don't need to cite my academic pedigree and be all "scientific" about saving battery life.
The point of this thread is an answer to all the threats I've seen on improving battery life and the countless posts I've seen on fully discharging a Lithium Ion Battery to "calibrate it"
The point I don't quite understand about your reply to this thread is that it just restates what I already pointed out only it's longer. Maybe if you have more words than me it makes you smarter...
but I stand corrected, I did mean a wipe of battery stats after a Rom Change and Only after a full power off charge, not intermittently.
but...
"one of the few things my post was accurate on" - Hmm, if it's an inaccurate post to you, just report it. - I assure you these are not claims and theories but pure fact.
I'm not here to get into a pissing contest about battery life, I'm just posting here to help people...
emalia said:
One question in regards to your post. I currently use the desk top cradle to plug in when I get home, will this mess with the battery too? It was made by Samsung I am confused as to why they would make something to use with your epic if it will hurt the battery.
Click to expand...
Click to collapse
I would advise that as long as you are charging your Epic in the cradle while it is not powered on, then you'll be perfectly fine. Charging it while it is powered on will cause unnecessary heat.
And I finally accumulated enough posts to cite my sources:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
I have to say that Laptop batteries are a lot different than cellphone batteries, the "do a full discharge after a few weeks" works great for a laptop battery but I would not do this with a cell phone battery. They just aren't the same internally. Laptop batteries are a bit more sophisticated.
actually, lithium ion batteries are best kept at about 50%, not 100
This thread is simply a point of ignorance about what is being described when people talk about "calibrating a battery" on an android phone. The process is not actually about calibrating the battery. It actually calibrates how the software reads battery information. You do see better battery life after going through it, but nothing has changed about the battery.
If you've ever flashed a ROM and suddenly found the battery to significantly higher or lower percentage displayed in the software meter, or if you found the battery seems to drain more quickly than previous(it doesn't, the phone just shows higher than actual charge to start), those are symptoms of poorly or not-at-all calibrated situations. The "battery calibration" process is a fix for that.
And OP, I'd say your understanding is rudimentary at best. While its true that Li-ion batteries don't "have a memory" (no batteries "have a memory", the memory effect was a result of the chemical process used by some batteries), li-ion batteries do show better usable lifetimes when charged according to certain standards. Again, its a matter of how the chemical process works and what wear the battery's internals develop depending on it is used.
akijikan said:
This thread is simply a point of ignorance about what is being described when people talk about "calibrating a battery" on an android phone. The process is not actually about calibrating the battery. It actually calibrates how the software reads battery information. You do see better battery life after going through it, but nothing has changed about the battery.
If you've ever flashed a ROM and suddenly found the battery to significantly higher or lower percentage displayed in the software meter, or if you found the battery seems to drain more quickly than previous(it doesn't, the phone just shows higher than actual charge to start), those are symptoms of poorly or not-at-all calibrated situations. The "battery calibration" process is a fix for that.
And OP, I'd say your understanding is rudimentary at best. While its true that Li-ion batteries don't "have a memory" (no batteries "have a memory", the memory effect was a result of the chemical process used by some batteries), li-ion batteries do show better usable lifetimes when charged according to certain standards. Again, its a matter of how the chemical process works and what wear the battery's internals develop depending on it is used.
Click to expand...
Click to collapse
Once again, I'm not in here to get into a specifics and scientific pissing contest on how batteries work, I just put a guide on how to improve your battery longevity.
Not everyone in here is an electro-chemical engineer with a concentration in battery physics. Or whatever. So, stop ripping apart my post with your blabbering physics. Just because I have a low amount of posts makes me inferior to you?
I'm sorry you sensed hostility in my post. But don't ignore what I'm saying about battery calibration.
I think Aki is right, we aren't calibrating our battery, we are resetting battery stats the software keeps. The reason we recommend this is b/c when folks change ROM's some can get miserable battery life in practice until they reset the stats. An experienced dev can tell you why, but it is a common enough fact to warrant wiping battery stats when switching ROM's.
Sent from my Epic 4G on XDA App
akijikan said:
I'm sorry you sensed hostility in my post. But don't ignore what I'm saying about battery calibration.
Click to expand...
Click to collapse
It was a bit hostile... I enjoy a good debate and rational thought though, I understand what you're saying, I'm not trying to get into the specifics, but it seems a lot of users are doing this "process" too much, and personally I don't think you should do it at all. I think you should do a full recharge (powered off, not discharge) then wipe battery stats. Period. No need for a discharge to 0.
People, this guy is just trying to help. There is no need to be rude. We are all on this form trying help each other. This whole idea is hurt when someone posts something and gets attacked. There is no need to call someone ignorant if you don't agree
Sent from my SPH-D700 using XDA App
codest3r said:
I think Aki is right, we aren't calibrating our battery, we are resetting battery stats the software keeps. The reason we recommend this is b/c when folks change ROM's some can get miserable battery life in practice until they reset the stats. An experienced dev can tell you why, but it is a common enough fact to warrant wiping battery stats when switching ROM's.
Sent from my Epic 4G on XDA App
Click to expand...
Click to collapse
Personally, I've gotten the best battery life when I do what I just posted above. Which is a powered off charge to 100% then a battery stats wipe. Viola, no need to discharge all the way to 0 and back to 100. It just tears up your battery in my experience.
tatoniss said:
People, this guy is just trying to help. There is no need to be rude. We are all on this form trying help each other. This whole idea is hurt when someone posts something and gets attacked. There is no need to call someone ignorant if you don't agree
Sent from my SPH-D700 using XDA App
Click to expand...
Click to collapse
I appreciate the support. If you think I'm dead wrong let me know. But the intent is far more important that the means of which I describe how the battery communicates with the phone.
I just want Epic Users to get the best out of their Epic.
I think a lot of people think they are calibrating their battery, but in all actuallity it's the information in the phone about the battery that needs to be callibrated.
gwcarpenter said:
I appreciate the support. If you think I'm dead wrong let me know. But the intent is far more important that the means of which I describe how the battery communicates with the phone.
I just want Epic Users to get the best out of their Epic.
Click to expand...
Click to collapse
You have to understand that the battery percentage is calculated by the phone. If the phone has no way of knowing the actual battery percentage accept with an indication that the battery is full or an indication that the battery is dead, then logic serves that one would have to perform a complete cycle to get accurate statistics. Let's say you have an electric car that's 'fuel' gauge is based solely on an indicator from the battery when it is full and when it is empty. It was initially calibrated to go ~300 miles on a full charge. Now say you get a new engine that might use energy at a different rate than the previous engine (analogous to say a kernel update). You don't really know the percentage of the battery until you record how many miles you've driven before the battery becomes empty. For the statistics to be accurate you must record the statistics over the entire battery discharge cycle. If the only indicator the software has is full and empty, the only thing you can gather from the statistics without a full cycle is the amount of energy that wasn't a full cycle.
Another analogy would be being blindfolded and sipping water through a straw. If you are told that it is full when you start and you drink 25% of it and then we fill it up again. Now you drink the same amount, how much is left (keeping in mind you are still blindfolded.) You have no idea, because you haven't done a whole cycle. You have no idea if you just drank 25% or 50% or 75% because you have never finished it.
My point is, is that you can't record the full capacity of batteries without doing a full charge, discharge cycle.
gwcarpenter said:
Lithium Ion batteries DO NOT NEED TO BE CALIBRATED.
Heat is the biggest enemy of Lithium Ion Batteries, if they get too hot, from forced discharges they actually develop tiny crystals on the inside of the cells that prevent it from being truly 100% charged.
So, in reality your phone is telling you your battery is 100% charged when it is only 85% fully charged inside the battery.
If you want to prolong your battery life follow these short and simple steps:
1. The closer you keep your phone to 100% the longer it will live.
4. Unplug your battery when it's fully charged. - Sure, that "Battery 100% Full" message is annoying, but maybe it was put there for a reason? Hmm.
Click to expand...
Click to collapse
Above are some things you said, and below I'm going to copy and paste some stuff from the article.
Although lithium-ion is memory-free in terms of performance deterioration, batteries with fuel gauges exhibit what engineers refer to as "digital memory". Here is the reason: Short discharges with subsequent recharges do not provide the periodic calibration needed to synchronize the fuel gauge with the battery's state-of-charge. A deliberate full discharge and recharge every 30 charges corrects this problem. Letting the battery run down to the cut-off point in the equipment will do this. If ignored, the fuel gauge will become increasingly less accurate.
The worst condition is keeping a FULLY CHARGED battery at elevated temperatures
If possible, store the battery in a cool place at about a 40% state-of-charge.
Avoid keeping the battery at full charge and high temperature.
While the battery is kept fully charged, the inside temperature during operation rises to 45°C (113°F).
Batteries with fuel gauge (laptops) should be calibrated by applying a deliberate full discharge once every 30 charges. Running the pack down in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate and in some cases cut off the device prematurely.
gwcarpenter said:
Personally, I've gotten the best battery life when I do what I just posted above. Which is a powered off charge to 100% then a battery stats wipe. Viola, no need to discharge all the way to 0 and back to 100. It just tears up your battery in my experience.
Click to expand...
Click to collapse
That is correct. Discharging to 0% does nothing. The most important thing is getting the battery as full as possible, and then reset the fuel gauge(wipe battery stats.) Personally, I use the external Samsung spare battery charger to charge the battery to full, then insert it in the phone, and boot into recovery and wipe batterystats.
What many don't understand is that wiping batterystats in CWM deletes the batterstats.bin file in data/system. So when you do a data wipe, you are wiping batterystats also. This is why it is important to have a full battery when flashing a new ROM. Something else to remember is that restoring data from a Nandroid backup will also restore an old batterystats.bin file, which is fine if the new ROM has a kernal that is the same or similar to the previous one, but it will negate any batterystats wipe you did before restoring data.
Related
Hello All,
First, let me just thank everyone on these threads for all the knowledge they have imparted to me! Thank you!
Now to my question: If I have my charger with me, is it best to keep the evo on and connected to a power source as often as possible? Or is it better to charge it once until the battery is full and then not plug it back in until the battery flashes the "battery low" message?
A friend and I were having a disagreement over this question and we couldn't think of any reasonable way to answer this question. I know that between our two MacBooks, which I understand might have a completely different type of battery, mine definitely gets much more battery life and I am convinced that this is because I have it constantly plugged in (though again, I'm not sure that this is true).
I will greatly appreciate your input on this matter!
Thank you.
http://www.batteryuniversity.com/parttwo-34.htm
Check this Thread http://forum.xda-developers.com/showthread.php?t=694441
For the record:
Simple Guidelines
Avoid frequent full discharges because this puts additional strain on the battery. 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. (In this respect, lithium-ion differs from nickel-based batteries.) Short battery life in a laptop is mainly cause by heat rather than charge / discharge patterns.
Batteries with fuel gauge (laptops) should be calibrated by applying a deliberate full discharge once every 30 charges. Running the pack down in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate and in some cases cut off the device prematurely.
Keep the lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level.
Consider removing the battery from a laptop when running on fixed power. (Some laptop manufacturers are concerned about dust and moisture accumulating inside the battery casing.)
Avoid purchasing spare lithium-ion batteries for later use. Observe manufacturing dates. Do not buy old stock, even if sold at clearance prices.
If you have a spare lithium-ion battery, use one to the fullest and keep the other cool by placing it in the refrigerator. Do not freeze the battery. For best results, store the battery at 40% state-of-charge.
Click to expand...
Click to collapse
(via above source)
Thanks!
Should I charge my phone when it has like 0.5% battery left always, or can I charge whenever it gets a little low, like 30-40%?
Also, can I leave my phone plugged into the charger overnight? Will that drain the battery?
I leave mine in the charger every night. And I'll put it in charge at work, too, or whenever a charging opportunity arises. With this kind of battery, it really doesn't matter.
Here is a very good article that discusses Lithium Ion batteries:
http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries
I don't get the article.
Does 4.2V mean 100% battery life?
If you want to charge it to 4.0 V, does that mean its like 90% battery life?
convolution said:
I don't get the article.
Does 4.2V mean 100% battery life?
If you want to charge it to 4.0 V, does that mean its like 90% battery life?
Click to expand...
Click to collapse
Not certain, but it seems the charger and/or battery on the Vision is designed so that it does not keep the voltage at 100% when its charging and full. I've noticed the battery meter periodically drop to 99% when still on the charger, then back up to "F" (full). While I know the battery meter is not really accurate enough to read to 1% increments; what this seems to indicate is that once a full charge is achieved, the system is going to let the charge drop below a certain threshold, then top off again, rather than keep the voltage at 100% constantly.
The table below is a little more easily digestible (not overly technical). It says you can keep the battery on the charger.
It also says not to let the battery discharge below 20%. Overdischarge of Li ion batteries can result in your battery no longer accepting a charge, on the off chance the safety circuit does not trip properly. The safety circuit is designed to prevent over discharge of the battery, but this has been known to fail, at least on other phones. And there is no benefit to letting the battery discharge below 20%.
http://batteryuniversity.com/learn/article/do_and_dont_battery_table
convolution said:
I don't get the article.
Does 4.2V mean 100% battery life?
If you want to charge it to 4.0 V, does that mean its like 90% battery life?
Click to expand...
Click to collapse
There are two terms you need to understand when it comes to batteries: volts and amps.
Volts is "static" for a battery, meaning it doesn't change. You have a 1.5V battery, it will always be a 1.5V battery. Now the capacity of the battery is measured in amps. A 1Amp battery has more capacity than a 500mAh battery. At 100% fully charged, you'd have 1000mAh (or 1A). At 90%, you'd have 900mAh.
What that article tells you is that your phone is charged to (or close to) 100% using a specified voltage (probably whatever the battery is rated at...3.7V?). Now batteries and chargers of the past had what's called a "trickle" effect, in which it still chargers the battery when it is (or close to) 100%, but at a much lower voltage. If you phone was to stop charging after it hit 100%, it would start to discharge. When you unplugged it (assuming you charge it over night) in the morning, you would have less than 100%. The trickle is so that your battery will still have 100% when you unplug it.
Think about if you filled up your gas tank and left your car running over night. When you woke up, you wouldn't have a full tank anymore. But if you left the gas nozzle in the tank while it was running, it would continually "top it off". That or gas leak everywhere and your car would burst into flames...therefore canceling the point that you wouldn't a full tank...
Anyways...Li-Ion batteries charge and behave differently that batteries of yore. It's bad to let it go down to almost 0%. It's also bad to let it continually sit on the charger. I personally charge mine every other day but I used to charge my Vibrant and HD2 every night.
The batteries in these phones have protection circuits to prevent over charging as well as over discharge. It is perfectly safe to charge over night as well as discharge until empty. What the display shows as 0% does not mean the battery has actually reached 0%. It is just were the protection circuit deems safe. It is possible to over discharge a Li-ion/LiPo battery which may cause it to no longer charge but there are ways to bring it back for the willing. Our phones, however, will not do this due to the protection circuit unless that fails. If that happens you need a new battery because Li-ion/Lipo batteries are very dangerous if over or under charged.
Also, the voltage is static in theory but in real life the the voltage does drop as the battery is discharged. The drop is not large however. A 3.7v Li-ion/LiPo cell will read around 4.2v at full charge and lowers to just over 3.7v at full SAFE discharge. If the battery falls below 3.7v, you will likely have damaged the cell. Again, our phone batteries have a protection circuit to prevent this.
ihateusernames said:
The batteries in these phones have protection circuits to prevent over charging as well as over discharge. It is perfectly safe to charge over night as well as discharge until empty. What the display shows as 0% does not mean the battery has actually reached 0%. It is just were the protection circuit deems safe. It is possible to over discharge a Li-ion/LiPo battery which may cause it to no longer charge but there are ways to bring it back for the willing.
Click to expand...
Click to collapse
It would require a special charger with a "boost" function, which most people do not have access to.
From the previously linked battery University page:
In spite of these preventive measures, over-discharge does occur. Advanced battery analyzers (Cadex C7000 series) feature a 'boost' function that provides a gentle charge current to activate the safety circuit and re-energize the cells if discharged too deeply.
Most of us let our battery drain low on accident from time to time. But it makes not sense to do it intentionally or make a habit of it, as it yields no benefit (some people think they are "conditioning" or "calibrating" the battery, which does not apply to Li ion batteries), and actually hurts battery life. Also from Battery University: "Do charge the battery often. The battery lasts longer with partial rather than full discharges."
There have been pretty occasional cases on the Touch Pro 2 forums of people over-discharging the battery, and rendering it useless. So it does happen. Some have claimed that the Android OS, or the Vision phone itself handles the battery better to avoid over discharge. Maybe so. But do you really want to test that theory, if it can most usually be avoided?
redpoint73 said:
It would require a special charger with a "boost" function, which most people do not have access to.
From the previously linked battery University page:
In spite of these preventive measures, over-discharge does occur. Advanced battery analyzers (Cadex C7000 series) feature a 'boost' function that provides a gentle charge current to activate the safety circuit and re-energize the cells if discharged too deeply.
Most of us let our battery drain low on accident from time to time. But it makes not sense to do it intentionally or make a habit of it, as it yields no benefit (some people think they are "conditioning" or "calibrating" the battery, which does not apply to Li ion batteries), and actually hurts battery life. Also from Battery University: "Do charge the battery often. The battery lasts longer with partial rather than full discharges."
There have been pretty occasional cases on the Touch Pro 2 forums of people over-discharging the battery, and rendering it useless. So it does happen. Some have claimed that the Android OS, or the Vision phone itself handles the battery better to avoid over discharge. Maybe so. But do you really want to test that theory, if it can most usually be avoided?
Click to expand...
Click to collapse
I agree that it can happen which is why I stated that the prevention circuit can fail though I do believe it to be a rare case that this happens. I charge when ever I am near a charger as I don't like to run low but I also don't freak out if I am close to dead. I also charge over night every night and have for years. I just don't believe that it is necessary to worry that my phone has been on the charger too long or that I am running close to 0% as there is redundant protection in place and for the most part, this protection works very well. Hell, your phone COULD burst into flames while holding it next to your ear due to the volatility of the Lithium Ion chemistry if exposed to air but that also very rarely happens.
I believe it is probably worse on the battery to watch movies on the phone while overclocked with the battery getting too hot than to discharge to 0% occasionally.
I do agree that it is pointless to try conditioning lithium batteries as they have no memory effect.
Reviving an over discharged Lithium battery should not be attempted by most. I fly RC Helis and my electrics use 3 or 6 cell LiPo's. On the very rare occasion I kill a cell, I isolate the bad cell and trickle charge until it matches the others and then resume balance charging. The batteries in our phones can be revived in the same manner. It requires low current and constant observation and should not be done by the inexperienced.
At the office I leave my phone in a cradle. When I get calls I remove the phone to answer and then return it to the cradle when done. My battery goes from 100% down to somewhere in the 90's then charges back to 100% in the cradle. Does this repeated process harm the battery in any way? I've read that these batteries don't suffer from the memory effect, but I'm still not sure if this counts as a charging cycle.
Sent from my Desire HD using XDA App
You should always let the battery run down completely some times maybe once a week.
Really? I've read on this forum that there is no need to do that with the new Lithium Ion batteries. I've even read that this could have a negative effect and you should try not to let the battery drain completly.
I don't understand why there isn't a proper battery care section in the manual. Its as if its some kind of voodoo science.
Perhaps not Once a week. But Once a "while"
The reason is that, Phone software uses approximation to calculate the charge left in the Battery. So over time, battery ages and software may not be calibrated to match with the battery's storage capacity. So draining the battery entirely and charging them fully gives the phone's software to assess the battery's health and recalibrate.
It's a lithium battery mate. The only way you can really damage it is by a complete discharge. So long as you don't switch the phone back on once it switches itself off due to low battery you needn't worry about anything else.
Also in theory the lithium batteries have a lifespan of say about a 1000 charges for example and everytime you charge it has one charging less left. This ofcourse isn't exactly how it is in practice but charging the battery alot wears it down. It isn't good either to keep it in the charger for a longer time after it's reached a 100%.
Hi,
this is only partly correct:
Suppose the battery can make 1000 (which I don't believe) charge cycles,
it means that you can charge 1000 times from empty to full.
If you just charge 1000 times from 50% empty to full it counts for 500 cycles!
So,
don't worry, let it stay in the cradle if you like
There are 500 opinions about that but believe, as I wrote is correct.
Theo
Yes, what I said wasn't exact science and I used 1000 cycles as an example, but from what I've read it is better to let the battery drain to less than 50% and then charge it full rather than charge 5% at a time. My previous post was meant to illustrate this.
Sent from my Leedroid powered pocketsized supercomputer using XDA App
geenome said:
You should always let the battery run down completely some times maybe once a week.
Click to expand...
Click to collapse
That's a load of crap, no offense... Lithium batteries have no memory effect and have absolutely no need to be completely discharged, that's a ancient thing from the time of nickel-metal hybrid batteries. The only actual reason for full charge cycles is to calibrate the device for that exact battery.
Keeping a lithium-ion battery in a charger most of the time will wear the battery down faster than getting it drain more and then charging it. Keeping the battery almost fully loaded/in a constant loading state wears the battery capacity by approximately 20% a year (can't recall the source/study just now)(EDIT: and my personal experience is that the battery capacity will wear that much anyway, no matter how you use it). The life-cycle of phones these days are roughly two years nowadays so IMO you can keep it in a cradle with no worries, if you wish. And lets face it, a new battery after a year of usage won't be that big an investment after all.
To add to the above post, running down a lithium battery completely does more damage than benefit. This is almost impossible though with normal use as the phone shuts down long before the battery is completely empty
I was curious about the discharge cycle when trying to get battery calibration stats. Does it matter if you use the phone regularly, or should you "beat it up"? Didn't know if that would skew the results.
Also, in doing some searching, I've seen some people mention that fully discharging the battery is a bad idea because of damaging the battery or reducing it's lifespan, which is obviously a direct contradiction of the whole calibration procedure. Anybody have any thoughts on that?
Thanks!
schick79 said:
...Also, in doing some searching, I've seen some people mention that fully discharging the battery is a bad idea because of damaging the battery or reducing it's lifespan...
Click to expand...
Click to collapse
I would just use the device normally.
As far as damaging the battery, it isn't going to happen. The people that say you will damage the battery by fully discharging it don't understand the modern Lithium Ion/Polymer batteries. Batteries now days have over current, over voltage, and over discharge circuitry either on the battery, on the device, or both.
When your Xoom says it is at 0%, the battery is not really fully discharged. It is at, let’s say 3.1 volts, which is far above the voltage (around 2.7 volts) required to damage the battery.
Everything you wanted to know about batteries...
http://www.batteryuniversity.com
"The battery indicator in the status/notification bar is a reflection of the batterystats.bin file in the data/system/ directory."
No, it does not.
This file is used to maintain, across reboots, low-level data about the kinds of operations the device and your apps are doing between battery changes. That is, it is solely used to compute the blame for battery usage shown in the "Battery Use" UI in settings.
That is, it has deeply significant things like "app X held a wake lock for 2 minutes" and "the screen was on at 60% brightness for 10 minutes."
It has no impact on the current battery level shown to you.
It has no impact on your battery life.
Deleting it is not going to do anything to make your more device more fantastic and wonderful... well, unless you have some deep hatred for seeing anything shown in the battery usage UI. And anyway, it is reset every time you unplug from power with a relatively full charge (thus why the battery usage UI data resets at that point), so this would be a much easier way to make it go away.
The whole idea of erasing that file having any effect on battery life is pure superstition and wishful thinking. The battery usage UI describes what your device has been doing that has been consuming battery; it doesn't change how the device is using the battery.
You want to "refresh" your battery stats? Charge your phone. When you unplug it again, the device knows it's at full charge (because the battery firmware says so), so the stats tracking treats that as a known milestone for reporting purposes."---Dianne Hackborn
"I can't remember enough about it to elaborate a lot on it, but HTC devices used to make kernel modifications as well as other changes that affected the devices charging. The original incredible was an example.
Essentially the kernel controls charging to an extent when the device is on, and HTC used to let the battery kind of discharge down to 90% and back to 100% more aggressively than other phones (i suppose so it wouldnt wear the battery out as quickly, since batteries choke themselves off once they fully charge as to not overcharge) That's where the whole bump charge thing got started because the phone would say charged when it would really be anywhere from 90% up.
Different OEMs have used different approaches to battery charge management. Usually some combination of hardware "fuel gauge" on the PCB or in the battery, kernel driver, and sometimes a userspace daemon. The design of the specific phone may be friendly or unfriendly to charging.
For example, on the Nexus One, we could leave the charge circuit on (providing power to the phone) but disable charge flow into the battery (once it reached 100%), avoiding overcharging. The fuel gauge was integrated with the battery and provided 3s and 30s average current reporting, as well as voltage, temperature, and charge level, which was really nice.
On some designs there isn't a way to power the phone from the USB connector without charging the battery, which necessitates stopping charging when the battery reaches full and allowing it to discharge to a point before charging again -- how far you let it discharge impacts battery life and user perception of "is my phone charging all the way". Then debate ensues about how to report the charge level, if it's better to report the "true" level even though users will complain about their phone "not charging all the way", etc, etc."
Dont mean to burst your bubble but been saying this for a long time.
Great detailed explanation though.
Forum fishing.... Who's biting!
i was not so much inclined into the battery stats thing..may be because my battery lasts me a day
.once you said it ....i did a bit of searching...then came up with the conclusion...
:highfive: goes to you
http://www.xda-developers.com/andro...-battery-stats-does-not-improve-battery-life/
And yet the myth lives on.
Yes guys, but if my buzz doesnt charge 100% never? This happened at a couple of time when i buy this phone and is happening now. Is any solution?
Sent from my HTC One S using xda premium