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Leave Phone on Charger

Discussion in 'Android Devices' started by jlh4480, Aug 2, 2010.

  1. jlh4480

    jlh4480 Newbie
    Thread Starter

    Hello Everyone,

    I recently picked up my EVO, and am loving it. Does anyone know if there are negative effects to leaving the phone on the charger? At work, I'm primarily in my office, and could leave the phone on the charger during the day and then it would always be full when I leave in the afternoon.

    Thanks for the input.

    joshyone likes this.

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  2. Intel

    Intel Newbie

    Leaving the phone on its charger can produce heat that can weaken your battery in the long run. So if you plan on leaving it on the charger then I would suggest turning off the phone while it charges. Just something I have read multiple times about mobile phone batteries.
    joshyone likes this.
  3. damewolf13

    damewolf13 live~laugh~love

    Whenever I am home, I leave my phone on the charger most of the time. I have seen no ill effects, and my battery life is between 15/20 hours depending on usage.
    vmbgap and joshyone like this.
  4. ScorpDX

    ScorpDX Android Expert

    The only issue is that it won't have a "full" charge when you unplug it. You'll see a rapid 10% drop or so. The phone doesn't trickle charge once reaching full like most phones do. It'll show 100% when you unplug it and then drop to 90% within minutes. You can unplug it and plug it back in 30 minutes before you leave or so and it'll charge back to full.
    joshyone and lillygirl7 like this.
  5. edlex

    edlex Android Expert

    The charging sub routine will never allow you to overcharge the battery so you can leave it on the charger as long as you want either off or on. The problem with the evo's charging routine is that as a safety measure, once the phone senses it's at 100%, it stops charging until the phone goes back down to about 90%. What that means to you is that you could take the phone off the charger thinking it's at 100% and within a short while it will drop very quickly into the 90's. To assure its at 100% you can unplug the phone for 2-3 minutes and replug. By taking it off the charger right when the light turns green you can assure youself it's at full capacity.
    joshyone likes this.
  6. TheAndroidWorks

    TheAndroidWorks Android Enthusiast

    joshyone likes this.
  7. IAmSixNine

    IAmSixNine Well-Known Member

    Leave it on the charger over night. It will be fine.
    As far as what the poster said about it diminishing the battery, i will not say anything negative about that.
    The device charges to full or close to full capacity then shuts off the charger. This prevents over charging. Li-Ion devices dont have a slow or trickle charge. I learned this from the old 2-way radio days when everything was Ni-Cad. When companies like Motorola and Kenwood introduced Ni-Mah and Li-Ion batteries they HAD to also introduce rapid chargers that were Tri Chemistry. Ni-Cad can be charged rapid or slow. But the 2 newer technologies were designed for Rapid charging. This is also the same reason pretty much all cell phones have rapid chargers.
    Your more likely to replace the device before you have to replace the battery. Weather it be physical damage or just new device comes out in a year or two that you want more then the EVO.
    Sure you see a small percentage of drop when its off the charger in the morning but thats just because if you leave it off over night, and the light goes green, then your back to using the battery power. Its actually dropping because you have been using the battery as soon as the light goes from Yellow to Green. It takes a few minutes to get the percentage to adjust to the actual battery level.

    Long story short, you can leave it on the charger over night and not have any problems. I do this to my EVO and am confident it will be ok.
    joshyone likes this.
  8. it'll be interesting to see long term effects of two different charging styles.

    i leave mine off charge from 7:30am until 6pm plus. maybe later, depending on how much i use it after work.

    gf has her on the juice during the day in her office, comes home and puts it back on teh charger. uses the phone during her daily train ride.
    joshyone likes this.
  9. Barats

    Barats Android Enthusiast

    If you do not take it off right away, you will see the huge 10% drop in a matter of minutes, even with light usage.
    joshyone likes this.
  10. meyerweb

    meyerweb Android Enthusiast

    Wrong. When the battery gets close to full charge, the charger shuts off completely. No more charge, no heat. If you leave it turned on while on the charger, the battery will gradually run down. At some level of discharge, the charging circuit will kick in again, until the battery is close to full charge, when it will stop charging again. This is all very well documented.

    What you describe hasn't been true of cell phones for many years.

    What WILL get the battery quite hot is if you're running something that drains the battery heavily (e.g., running GPS Navigation, Pandora and 4G all at once). But that's what the phone is designed to do. It'll reduce battery life somewhat, but since you can get batteries for $5 each, it's hardly a major concern.

    This has nothing to do with leaving it on the charger. If you took if off the charger as soon as it was fully charged, the battery would drop the same amount over time. An example: Let's say you plug the charger in at midnight, and the battery is fully charged at 2:00 a.m. If you leave the phone on and the charger connected, the phone runs off the battery until you unplug it, say, 6 hours later. But if you unplug it at 2:00 a.m., as soon as the battery is fully charged, the phone, umm, runs off the battery until 8:00a.m. IOW, it'll use exactly the same amount of battery whether it's plugged in or not.

    See above paragraph.

    Truth, but difficult to deal with in normal usage. LI batteries don't like beeing overcharged, and don't really like being fully charged. Nor do they like being fully discharged. Cars with LI battery packs (like the Volt), maintain the battery pack between 25% and 75% to maximize battery life. But the battery pack in a Volt costs something like $20,000. Keeping that alive for a long time makes sense. I'll put up with buying a new battery every 12-18 months in exchange for not worrying about it on a daily basis.
    joshyone likes this.
  11. ScorpDX

    ScorpDX Android Expert

    That and these batteries now days are built much better and will last longer than this phone will be a relevant device no matter how hard you are on them!
    joshyone likes this.
  12. TheAndroidWorks

    TheAndroidWorks Android Enthusiast

    I have a 4 year old HP laptop with a 12 cell battery that still gets a full a 5 hours of continuous use. :) My old treo 650 which is now retired had the same battery for 5 years and still had better battery life than my hero, evo, Dx, etc.. :) I do realize that is like saying that my volkswagen gets further on a tank of gas than my corvette, but it is impressive none the less. I am just making the case that someone that understands the dos and don'ts of battery care can maintain charge capacity life of Li batteries much longer than the average bear and it does add up over time. I think the absolute quickest way to kill batteries is to keep deep cycling them over and over and over.... my ex girlfriend had 2 year old macbook pro that could literally not be unplugged for more than .5 seconds or it would totally die, her treo also got abot 1/2 the life of mine despite that fact that I used mine far more. You can probably guess why our batteries had different performance levels.
    joshyone likes this.
  13. leebo

    leebo Newbie

    Because she dumped you?
  14. Crodley

    Crodley Android Enthusiast

    Whenever I bump into an Iphone lover at work and they try to compare our phone with theirs and scoff at me saying the iphone is much better, I ask them, "Can your phone do this?" And I pull one of my extra batteries out of my pants pocket and hold it up. They sputter and say no with a frown most of the time.

    One person even said, "I can't seem to figure out how to remove my battery yet." I had to break it to them that they can't.

    I friend at work has an iphone and needs it charged because of a bad health situation with a family member at home, so he won't use the phone at work, afraid he will run it down and not be able to charge it and miss that important call.

    Yes, I LOVE my HTC EVO :)
  15. hfwplaya08

    hfwplaya08 Member

    how much are batteries and is there a link where i can buy them? also, are these sprint htc sponsored? or just a third party make?
  16. ScorpDX

    ScorpDX Android Expert

    All over ebay for cheap. Some are HTC some are aftermarket.
  17. meyerweb

    meyerweb Android Enthusiast

    Many of us have purchased the ebay 2 batteries + charger deal for about $10 to $12. I have 2 of those batteries, and they work fine. I'd estimate they last for about the same length of time as the OEM battery, maybe slightly (10%) less. I haven't done identically controlled tests, so can't be 100% accurate.

    Again, though, at 2 for $10 it's hard to go wrong.
  18. TheAndroidWorks

    TheAndroidWorks Android Enthusiast

    LOL, perhaps our charging philosophies led to irreconcilable differences!

    Those ebay batteries and the charger work great. I was using them with my hero before the EVO came out and have been very pleased with them in both devices. The only gripe is that when I use the USB port on the charger with my EVO, it messes up the touchscreen and makes it unresponsive. Some sort of grounding issue, but not a big deal!
  19. novox77

    novox77 Leeeroy Jennnkinnns!

    there's no short term harm in leaving your phone in the charger, but try not to do it too much. It does affect the longevity of your battery. If you plan to get a new phone in under two years, then it really doesn't matter.

HTC EVO 4G Forum

The HTC EVO 4G release date was June 2010. Features and Specs include a 4.3" inch screen, 8MP camera, 512GB RAM, Snapdragon S1 processor, and 1500mAh battery.

June 2010
Release Date

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