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Charging Battery Overnight?

Discussion in 'Android Devices' started by robo21, Aug 3, 2010.

  1. robo21

    robo21 Android Expert
    Thread Starter

    I spoke to a Samsung tech about charging the battery. He said "After your initial full charge, if you charge the battery for more than 4 hours you will reduce the life of your battery." I was stunned, why not include a smart charger that would curtail the charge current as the battery reached full charge? He had no answer. We know the answer.

    So no more overnight charging for me.

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  2. SamsungVibrant

    SamsungVibrant Android Expert

    I don't think he knows what he is talking about. The phone prompts you that charge is complete, this makes me think that the phone also turns off charging of the battery.
  3. robo21

    robo21 Android Expert
    Thread Starter

    Or it could be that it prompts you so that you don't overcharge it. I'm just relating what the Samsung (level 2) rep told me. FWIW YMMV.
  4. 2FR35H

    2FR35H Android Expert

    I would trust the Rep and not overcharge because if they are reps of a certain product then they have to know the ins and outs of the product.

    Overcharging is never good in any case.
  5. krichek

    krichek Android Enthusiast

    Exactly, I charge mine overnight and every morning when I take it off the charger it is at somewhere between 97 and 99%. Once it reaches full charge it pops up the notification and stops charging.. I've been meaning to leave it on the charger and see if it'll start auto charging again after a certain point but am always in a hurry in the morning hehe.
  6. justjimjpc

    justjimjpc Premium Member

    From another thread ...

    The Samsung tech was blowing smoke and doesn't know what he is talking about ... these batteries can be charged and stayed connect full-time without issue... the battery doesn't have the memory issue of the old NiCad batteries of years ago. So you can charge them at any point in their cycle and not have any bad effects... The battery charging circuits in the phone will limit and prevent the battery from becoming over-charged or damaged... If that circuit failed then there could be a problem ... but most likely you will never see that happen ..
  7. robo21

    robo21 Android Expert
    Thread Starter

    Perhaps but no one ever said anything about a "memory issue." Of course, lithium ion and NiMh batteries have virtually eliminated the memory issue that was so common with NiCad batteries. We know they are not nicads, they can be charged at any time. It is however beneficial to take them down to 90% occasionally before recharging. The newer batteries can be damaged by completely draining them. Lithium ion and NiMh batteries can also be damaged by overcharging. The question is whether or not the phone circuitry or charger circuitry limits the charge current when the battery reaches full charge.

    It could be that the level 2 tech was wrong. But I haven't been able to find written confirmation of that anywhere as of yet. And it does state in the Samsung Vibrant User Guide that a discharged battery takes approximately 4 hours to reach a full charge.

    Justjimpc, please, if you could refer me to any technical reference(s) on this phone that establishes the existence of "overcharge protection circuitry" in the phone or the OEM charger I would be most grateful. I have looked and asked support and so far documented information has eluded me. From the tone of your reply it sounds like you have concrete information that establishes the existence of such circuitry. Thanks in advance.
  8. zillah2004

    zillah2004 Member

    Could you please refer us to any authenticated documentation from one of a manufacturer

    I have got Samsung F480i and I am located in Australia.

    Today the tech guy at the Samsung authorized dealer told me same thing :
    I suppose not to overcharge my Samsung F480i overnight, because that would damage the battery.

    I tried to search Google using this phrase :

    Outcome I got different ideas and opinions contradict each other.
  9. becklox

    becklox Lurker

    This is just a simple issue. you don't need to be techie to know that over charging the battery will make a bad effect in the future.
    -The rep said that it will reduce the life of the battery means that the effect will be on a long run not on the spot.
  10. robo21

    robo21 Android Expert
    Thread Starter

    Bottom line, if you can charge your watch just enough to reach full charge you will likely be better off than just leaving it plugged in overnight or for extended time periods. ;)
  11. over88mph

    over88mph Member

    Why would one think that a phone that can do a million things can't "know" when it's charged and "protect" itself ?
    I guess the same person that would ask for manufacturer documentation of how each mircoscopic circuit in the device works.
  12. comatzd

    comatzd Lurker

    As an engineer that works with LI-Ion charging systems, I would tell you the battery charging circuit HAS to disable charging when the battery is full. If it didn't, the battery would overheat, vent, start on fire, and burn down anything near it. No reputable battery manufacturer would sell to company that does not include over-charge and over/under-voltage protections in the charging system.
  13. laramavreen

    laramavreen Lurker

    Does ocercharging damages the phone? i mean if it will damage the battery or not, you can always buy another battery. But is overnight charging damages the phone? i really need an answer. i fall asleep while charging :) so i left it charging for almost 8 hours. the manual indicated "do not over charge for a week" .
  14. robo21

    robo21 Android Expert
    Thread Starter

    Don't worry. You will not damage your battery or phone in that amount of time. What I generally do is charge the phone after work and it is fully charged by bedtime. Then I disconnect it while I sleep. It has at least enough charge for all night and the following day.
  15. Metroid Prime

    Metroid Prime Oil Can!!! Oil Can!!!

    No, you can't overcharge the battery. :)
  16. akash4u

    akash4u Lurker

    Reading all these posts here, I want to share my real experience with overcharging (may be) with Samsung Galaxy Y ( 700mA 5V USB Charger).

    My original battery swell to nearly 2 times its width suddenly in a fortnight, and back went to nearly 10% of original earlier it was nearly 80 - 90% of the original before a month.

    I used to plug car charger 5.5V,other chargers and laptop charging also ocasionally, and used to keep charging overnight 50% of the times.

    I dont know why my original batt. lived out in just 1.5 years of purchase of mob. in which I guess I charge atmost once a day. So, this hardly equals 500 charge discharge cycle. Original batt, should give near about 800-1000 charge discharge cycle.

    When I gone to buy original batt. from a Samsung (only) Retail shop, retailer opened the back cover to mount/check new batt.

    Just after opening and seeing the cond. of my old batt. he said the line "Do you used to charge the phone overnight."
    I said ,yes. He said it is deduced from the batt.

    And, he strongly recommended not to charge overnight/overcharge the new batt.Your old batt. lived out due to overcharging. Usually Original batteries run for more than 2 years.

    I asked him,"but the phone has internal circuitry to protect overcharging, and phone shuts down charging once batt has full charged." He said no whatever may be the reason but today phones are not coming with good battery monitoring circuits and they are getting damaged to overcharging, and in the long run batt is gets ruined.
    Thats it,

    I am also a Electrical and Electronics Engg. I know there are circuits just below the battery connectors on a battery width sized pcb ( I once opened it),

    It has temperature sensor (generally on the middle pin which varies voltage linearly with temperature ), short circuit protection circuit ( as batt opens when more than the set level of current flows through it), over discharge protection ( you will get zero voltage on the terminal if pot. diff. of batt. goes below 3V ) and overcharge protection ( may be charging stops or trickle charging start after batt has reached 4.2V , I have not tested it yet but now I will as this happened to me).

    By googling around I have read that li-ion batt. swell due to overcharging.

    I think most people here who are saying very confidently that batt. are overcharged protected don't have any authentic proof.
    But, ya I do agree that costly phones ( more than 200$ ) do have protections as good companies don't skip these small circuitry.

    But cheap phones/companies may have cheap circuitry or no overcharge circuitry to cut down the production cost .
    Mine is Galaxy Y (less than 150$) ,may be I have burnt out overcharge pro. circuit by using 5.5V charger.

    So, whatever may be the reason, its good idea to abandon your habbit of charging overnight or reduce its frequency if you can't.
    Otherwise if you are comfortable spending 10$ more in a year, its really not a big deal to bother that much.
    scary alien likes this.
  17. scary alien

    scary alien not really so scary
    VIP Member

    Welcome to the AndroidForums, akash4u!

    Good info and interesting take--it's hard to really know what's inside a given manufacturer's battery without actually taking it apart, but I've never liked the idea of leaving my devices plugged-in and unwatched while I sleep anyway.

    Here's an interesting thread over on XDA about battery charging (and bump-charging) that might be relevant to your points:

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

    Anyway, good food for thought! :)

    Cheers and thanks for signing-up with us here at AF.

Samsung Vibrant Forum

The Samsung Vibrant release date was August 2010. Features and Specs include a 4.0" inch screen, 5MP camera, 512GB RAM, Hummingbird processor, and 1500mAh battery.

August 2010
Release Date
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