All you ever wanted to know about batteries and chargersTips

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  1. nkk

    nkk Well-Known Member

    "Work in progress, please do not move to another forum, per EarlyMon"

    This is a thread for all battery info, etc. It will approximately follow the layot detailed below by EarlyMon:
    So...I am making the thread now with merely a link to another post I made. I am student, so time is precious. However, over the next three or so weeks, I will complete this and it will be a self contained item.

    The seed post


    So I am going to use Hide tags for almost all info until this is done. That way everything can be compartmentalized and this post will not be absurdly long. When it is done, I will cut and paste into a more logical organizational structure.

    What Charger can I use? What should I look for?
    You need a charger that fits standard USB Spec. Now, instead of reciting spec here (if you are interested, has it and it is fairly interesting) I will say this:

    Look at the charger that came with your phone. It should have a few important values in two different fields.

    It will say input, and under that it should accept 120-240 Volts (V), meaning the charger will work internationally. It will also have a frequency. If it accepts the correct votage range, the frequency is good.

    Under output, it will say something like 5.5V, 1A. This means it will put a difference of 5 volts across the charging pins and will max current out at 1 ampere.

    Whenever you but a new charger, make sure it matches those specs. Voltage MUST match (overvolting a cell causes explosions and undervolting it is less than effective). The max current is a bit more lenient. If it is less than your OEM charger, the charger will work just not as quickly. If it is more, that means that it will allow more current through. I would be super safe and stick with same or under, but not over.

    I recommend as a place to get cheap but reliable chargers.*

    Is there any procedure I should do to break in my battery?

    Yes and no. You do not need to do anything to break your battery in. Various manufacturers have processes to break in their cells, but these processes are not necessary and proprietary. As a consumer, you have nothing to do.

    Having said that, you probably should start with a full charge and then go until a full discharge. That way the internal battery meter (which bases its battery% on voltage levels) will be properly calibrated from the start.

    So...I got my phone and did not calibrate my battery. What now?

    Do not worry. There are two options, depending on if you are rooted or now.

    If rooted:
    Go into your recovery and find the option for clear battery stats (it is under advanced in CWM, and I cannot say if all recoveries have it). Now, proceed to the stock directions.

    If stock:
    Do a full battery cycle or two by doing the folliwng:
    Turn your phone off and charge until full. Turn it on and take it off the charger. Use it (with no charges in between) until it dies by itself due to the battery. If you can avoid restarting it during this time that would be great. IF you want to give the phone an additional data point (probably a good idea), do the full cycle again.

    Note that it is a bad idea to do this too often. As I have said in other questions, fully discharging your battery too often is bad and will result in an accelerated degradation of capacity.

    Can I charge my battery in the middle of the day? What are the consequences (n terms of battery lifetime, etc) of partial charges for the battery?

    Li-ion batteries work well with partial charges. A given battery is rated to a lifecycle of X charges (usually in the thousands). This number represents the number of cylces before your battery holds a significantly less amount of charge then it did out of the factory. Usually it is 60% of original capacity, so it is quite a decrease. These numbers are ballpark figures are vary (sometimes greatly) with things like average operating temperature, average discharge current, and other general operating conditions.

    So, you might think that if I get about X charge cycles before the battery has a significant loss of capacity, then I should only charge it when it dies completely. That logic is sound, but wrong. Li-ion batteries do not use a full cycle when doing a partial charge. When you charge a battery from 60% to 100%, you used about 0.4 of a cycle. From 30% to 90%, about 0.6. So, partial charges or good.*

    Now, on the other side of this, I can say that full discharges are bad. Now, you may want to do them every once in a while to calibrate your battery stats (see the question regarding calibration for more info), but that is a situation where the downside is outweighed by the good. If you fully discharge your battery every cycle, you will see an increased rate of capacity degradation.

    *A gain, remember that since the total cycles is a ballpark statistical average given by the OEM based on testing that may or may not match your usage profiles, there is no real precise accounting to be done here, just theoretical partial and full cycles and a theoretical max

    Does it hurt the battery to leave the phone plugged in all the time?

    Yes, in the long term it will. What happens is that the battery will do two things:
    1. It will stay in the 90-100% charge range, which is less than ideal for long term storage.
    2. It will probably run a bit hot (70 to 80 deg F). This depends on phone model, ambient temperature, etc.

    Now, you have to think. If you have an old phone in a dock that you use as an alarm, does it really matter if the battery life eventually degrades to 20 or so minutes? If no, the go one and just leave it plugged in. If yes, then reevaluate your options (change your habits or buy a new battery every so often).

    How do I store my battery for the long term (2 weeks or longer)?

    Follow what I call the 60-60 rule. Charge it to 60% and leave it at 60 degrees Fahrenheit.

    Optimal storage for a Li-ion batter is in the 40% to 60% charge range and around 55-65 deg F (these are approximate numbers. You may see things like 50% charge and 60 deg F, or whatever. Different, but all in the same range).

    Your battery will eventually discharge a bit from 60% to around 40% charge, so you should check up on it every couple of weeks and charge it back up to 60%. If it discharges to below 40%, then it is entering conditions not conducive to being stored properly. For temperature, it should be relative stable at around 60 deg F. Small fluctuations are fine (again, it is a range not a single value).


    *Any product recommendation I give is based on my past experience with said product. Past performance in now way guarantees future reliability. My recommendations are made in good faith and I accept no return or compensation from anyone for making them. I am not responsible for any event which occurs as a result of you following or not following my recommendation.

    EDIT: If you have any questions you would like to see answered here, please post them. I am sort of at a loss for common FAQ material, so do not be shy.

    1.6.2011: added questions, changed some formatting for easier reading (bolded FAQ questions).

  2. nkk

    nkk Well-Known Member

  3. BabyBlues

    BabyBlues Trouble Just Finds Me! VIP Member

    I look forward to learning more.
  4. Laxstar785

    Laxstar785 Well-Known Member

    Cool..subbed to the thread ill keep up to date as best I can
  5. AndroiDad75

    AndroiDad75 Well-Known Member

    Thanks nkk, Look forward to learning something myself.
  6. Namrak

    Namrak Well-Known Member

    Nkk, you may want to include how to handle battery charging during the first few charges. I have read there are certain ways to charge the battery the first few times to improve its life, etc (I think its called bump charging?). Thanks
  7. nj02vette

    nj02vette Well-Known Member

    There's old techniques that do improve a batteries life. And herein lies the problem, they are old. Modern charging circuitry has all the parameters built in, so you don't need to do anything fancy.

    You'll get differing strong opinions on this, but I haven't seen any evidence to support requiring any special charging. Most people who do claim these work are going off the battery monitor in the phone, which takes several cycles to learn the battery profile in the first place.

    There comes a time when "conventional" wisdom doesn't apply. We don't pump the gas pedal before starting a fuel injected car anymore. Nor do we worry about buying pork in the summer. And these advanced batteries aren't old NiCad cells. There's no memory, and no special techniques are required.
    Crashumbc and Namrak like this.
  8. nkk

    nkk Well-Known Member

    You are both right an wrong. I have little time, so I will present the info to you in bullets:

    -You are correct that the consumer does not have to follow a specific regimen

    -the manufacturer, however, does. I think It has to do with a uniform coating of degraded cathode over the cathode crystal structure That way ther is barrier of sorts to future degradation.oxidation

    -This is a proprietary process

    -my advisor in the lab I worked in had also worked in the JPL (Jet propulsion laboroatory). They tried ordering batteries from A123 systems (best in biz for large Liion bats). A123 did a special initial charge/discharge process on them. JPL wanted the batteries to test with, to keep results sstandardized they asked a123 what they did. a123 said it was a trade secret and that they had to do it to all batteries.

    So, it is not necessary. Even if the manufacturer does it it is probably not necessary so much as it ensures consistency. But it does do something

    Sorry for typos...rushed.

    Namrak likes this.
  9. nj02vette

    nj02vette Well-Known Member

    My post was written from the point of the consumer, so in that we completely agree. The consumer has absolutely nothing to do special. Just plug it in and charge.

    Just like the consumer doesn't have to know injector flow rates and timing advance in modern computer controlled cars. Just turn the key and go. My point was there is a lot of old world thinking that gets applied to new technology which isn't applicable anymore. You're fairly young and probably don't remember having to do all sorts of tricks with rechargable batteries to improve capacity and life. But that day has passed and "conditioning cells" (at the consumer level) isn't applicable anymore.
    BlackHawk1776 likes this.
  10. nkk

    nkk Well-Known Member

    OP edited with a few FAQs and a plea for questions from everyone.

  11. Mahalo

    Mahalo Well-Known Member

  12. Ytram

    Ytram Well-Known Member

    Is it bad for my battery to just leave my phone constantly plugged in? This is actually for my OG Droid that will be replaced by the SGN(soon I hope ;)). I intend to buy one of those multimedia docks for it and use it as my alarm clock/radio, and I'll probably never remove it from the dock and leave it constantly plugged in.

    If I've heard correctly, once the battery is fully charged, the phone won't switch to "AC Power Only" or something like that, but will actually let it drain approximately 5% before charging it back up to 100%.
  13. taxtherich

    taxtherich Member

    Does it hurt the battery life to partially recharge the battery in the middle of the day?

    i plug in my phone to the car charger between trips to get extra battery life. instead, should i just let it completely discharge before i plug it in?
  14. standardtoast

    standardtoast Member

    This seems like the perfect place to have my confusing question answered.

    Long story short: my in car charger doesn't supply enough power to stop the battery draining over long trips.

    I've got one of these, which Griffin says supplies 1amp. This worked great on my Wildfire, and charged much faster than the standard 500mA charger I had before.

    Bought my Nexus ~1.5 weeks ago and I was having trouble getting the phone to display "Charging (AC)" while in the car (I'm lead to believe that "AC" charging is 1 amp, and "USB" charging is 500mA). A swift bit of googling later, and I cut open a USB cable and shorted the D+ and D- wires on the phone side. This did the trick! It displayed "Charging (AC)", oh happy days!

    However, the charge is still woefully inadequate, and after my test today, it seems only marginally better than no charge at all when running the Navigation app. I thought it was the cable, so I switched to the one that came with the phone, and another I had from my old Wildfire, no change.

    Could anyone shed some light on my confusion? Or recommend a charger/cable combo that will allow my phone to gain a net increase in charge while having the navigation app running?


    EDIT: Here's a screenshot of my battery drain while charging (over AC apparently) and uskng Navigation.

  15. monitron

    monitron Active Member

    I am having the same issue. This seems to be a very hungry phone with the screen on at full brightness. (at least, the Android battery stats indicate that the screen is the primary source of drain). If I turn off the screen entirely and just use Bluetooth to play local audio, the percentage creeps...up...very...slowly.

    I plan to run to Best Buy later on today to pick up a few chargers to try out. Some of them claim to supply 2 amps or more. If I find any that can keep the Nexus happy, I'll report back.
    standardtoast likes this.
  16. nkk

    nkk Well-Known Member

    So sorry for not answering your questions, but I am in the middle of finals so I am sort of preoccupied. :rolleyes:

    I will try to answer your questions vaguely this weekend, and then with real answers on Friday when I am done.

    standardtoast likes this.
  17. Anyone know how to get a blackberry or original droid charger to work with the Nexus?
  18. jraskell

    jraskell Well-Known Member

    I just plugged my OG droid charger into my Nexus and it charged it. Didn't have to do anything else.
  19. nkk

    nkk Well-Known Member

    FAQ question #1 answers that question almost exaclty. There is no magic to get it to work, it will work. It may charge a bit slowly (IIRC BB chargers are 500 to 600mA, whereas stock Samsung is 1A).

    Also, OP updated. I do apologize for the delay (I haven't said that before...:rolleyes:).

    Keep the questions coming!


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