Droid 4 Battery Swelling

Discussion in 'Droid 4 Tech Support' started by tailwinddon, Jul 20, 2013.

  1. FoxKat
    Offline

    FoxKat DF Super Moderator Staff Member Premium Member

    Joined:
    Apr 2, 2010
    Messages:
    8,610
    Likes Received:
    822
    Trophy Points:
    113
    Location:
    Pennsylvania
    I'd say...half-right. You are avoiding the bottom 20% of the charge cycle, which is good as it doesn't stress the battery to pull every last drop of power from it...but you are running into the top 20% (*from 80% to 100%), so in that end of the spectrum you are putting the battery through another stress which is to eek out every last space of unused storage and shove electrons into them. So you would likely gain a benefit of a longer battery lifespan due to avoiding the bottom, but no where near the 500% potential lifespan increase available if you avoid both ends of the charging cycle.


    Mountainbikermark is spot on. If you stay in the middle of the ranges specified, or in other words, never let it go below 20% and never let it go above 80%, you will reap rewards of a longer lasting battery. Of course, this also means that between charges you only have up to a maximum of about 60% of the battery's capacity available to you at any given time. So as with just about any decision we make as Humans, there's a trade-off for one versus the other...

    As for the "Bump charge" method, that is as he's indicated VERY BAD for these batteries and will dramatically shorten their lifespan. Look at it this way. If you blow up a balloon to 75% of its capacity every time, it will withstand hundreds of inflations. But if you inflate to 100% each time, you'd be lucky if it lasted more than a couple dozen - if that. I know that's not a good analogy, but it does prove the point. If you stress something to its limits consistently, it will likely fail far sooner than the average lifespan of one which is not stressed. Since the battery is not a mechanical device, but is instead an electro-chemical one, the physical aspects of stressing the battery happen at mollecular levels - far too small for the eye to see, however they are actually mechanical in nature since they break down the internal electrode making it less able to move and store electrons efficiently.
    Last edited: Jul 21, 2013
  2. dezymond
    Offline

    dezymond Tech Support Mod Staff Member Premium Member

    Joined:
    Nov 11, 2009
    Messages:
    10,756
    Likes Received:
    571
    Trophy Points:
    113
    Location:
    Bay Area, California
    It all makes sense and the analogy is good.

    One question then. Let's say I stay out of the bottom and top 20%, would I notice an increase in everyday battery life? Or are we strictly talking about the battery life cycles when it comes to these? Cause if it's just the battery life cycle, then in my specific case I can at least get a brand new battery and easily replace it.

    I'm pretty sure there is no increase in everyday battery life by staying within the 20-80% range, but just want to make sure.
  3. mountainbikermark
    Offline

    mountainbikermark DF Super Moderator Staff Member Premium Member

    Joined:
    Sep 5, 2010
    Messages:
    3,355
    Likes Received:
    456
    Trophy Points:
    83
    No difference in day to day until down the road when the screen time remains what it was a thousand charges ago vs if you do full recharge/discharge each time. If you are unlike my wife who only upgrades her phone about every 3-4 years it's not going to be a notable effort to stay between those parameters

    Support Our Troops!!!
    <><
    A Rezound phone was used for this Tapatalk post
  4. FoxKat
    Offline

    FoxKat DF Super Moderator Staff Member Premium Member

    Joined:
    Apr 2, 2010
    Messages:
    8,610
    Likes Received:
    822
    Trophy Points:
    113
    Location:
    Pennsylvania
    OK, let's differentiate "runtime" from "lifespan". Runtime is the length of actual time the battery will supply power sufficient to run the device based on some specific percentage of capacity. From a full charge at 100% to completely depleted at 0%, this would be the maximum capacity. So in the case of a brand new battery that has been fully charged properly, and since it's bad practice to allow the battery to discharge below annoy 10% let's assume for explanation purposes that the expected runtime for that battery to the point at which it indicates that it's time to charge (10%), would be 18 hours (or 2 hours for each 10%). So then from that we can extrapolate that if you only charge to 80% and use to 20%, you are using 60% of the battery's capacity, and at 2 hours per 10%, that means a runtime of 12 hours.

    Whether you charge to 100% and use to 40%, or you charge to 80% and use to 20 %, or you charge to 60% and use until the phone powers down on its own at 0%, you will get 12 hours of runtime in all three scenarios.

    Now, lifespan is the time from when the battery leaves the factory as a brand new baby boy or girl, until the time when it can no longer keep up with others on the dance floor. In numerical terms, if a battery is supposed to be able to take a charge of 3,300 mAh (its rated capacity), then one would expect it will do that the very first time it's charged. Each subsequent charge will reduce that capacity ever so slightly but over time will result in the battery having a significantly reduced capacity. A 10% reduction in capacity would mean the battery will now only hold 2,970 mAh, and a 20% reduction means it will now only hold 2,640 mAh.

    A battery that's at 90% of rated capacity will supply 90% of the runtime for the same percentage of capacity used (since the capacity is now 10% less than before). Using the brand new 3,300 mAh battery above as an example we can calculate that each hour consumes 165 mAh to a 10% charge level remaining (3300-10%=2,970/18=165). So then if we use that same formula with the battery that has the 10% reduced capacity, we arrive at 148.5 mAh available with each 10% of power available (2,970-10%=2,673/18=148.5) . Since we need 165 mAh to give us 2 hours of runtime, we will be falling short by 10% in time, or 6 minutes and (165/60=2.75 per minute) and (148.5/2.75=54 minutes per 10% consumed).

    SO...a battery that is only able to hold 90% of its rated capacity will yield a reduced runtime of an equivalent 10% less for the same numerical percentage of power used, all other things being equal. Therefore that battery which in the first example gave you 12 hours for the 60% consumed from between 20% and 80% charge, would now only give you 10 hours and 48 minutes (12 hours*60 minutes=720 minutes, 10.8 hours*60 minutes=648 minutes - or 10 hours 48 minutes).

    And if that battery were at only 80% of rated capacity or "end of useful life" as deemed by the manufacturers, it would only supply 8 hours and 36 minutes for 60% of capacity. A full charge to fully depleted for a new battery as illustrated at the top, would supply 20 hours total, whereas one that is no longer "useful" (only able to hold a charge of 80% of original rated capacity), would only be able to run 16 hours before being completely dead.

    In the case of someone whose phone battery is easily replaceable, this may not be such a big deal...and they may actually notice the reduced runtime sooner than the 20% threshold manufacturers specify, so they might decide to actually replace that battery even sooner than when the manufacturer indicates is time. On the other hand with someone like me whose phone is a Razr MAXX, I would likely be more concerned about lifespan since replacing the battery is a big hassle.

    Edited to correct for a divergence in my math by 10%.
    Last edited: Jul 22, 2013
  5. leeshor
    Online

    leeshor DF Super Moderator Staff Member

    Joined:
    Jan 30, 2012
    Messages:
    2,896
    Likes Received:
    359
    Trophy Points:
    83
    Location:
    Norcross, GA - USA
    Good post @FoxKat but we are getting a tad off topic. :icon_ banana:
  6. dezymond
    Offline

    dezymond Tech Support Mod Staff Member Premium Member

    Joined:
    Nov 11, 2009
    Messages:
    10,756
    Likes Received:
    571
    Trophy Points:
    113
    Location:
    Bay Area, California
    Hehe yup, my fault, but I'm sure whoever reads what FoxKat wrote will learn quite a bit, I know I did.
  7. FoxKat
    Offline

    FoxKat DF Super Moderator Staff Member Premium Member

    Joined:
    Apr 2, 2010
    Messages:
    8,610
    Likes Received:
    822
    Trophy Points:
    113
    Location:
    Pennsylvania
    Well, yes... and no. Proper care of the battery and more frequent, gentle partial charging/discharging cycles will not only yield longer lifespan and greater runtime during it's relatively longer life (or perhaps more accurately stated - a more gradual diminishing of runtime over the same time period), but will also not suffer the ill effects of swelling either as soon or possibly not at all, or at least not directly due to stress from charging and discharging. It's all interrelated since it's chemistry at its most rudimentary level.

    Sent from my DROID RAZR using Tapatalk 2
    Last edited: Jul 22, 2013
  8. leeshor
    Online

    leeshor DF Super Moderator Staff Member

    Joined:
    Jan 30, 2012
    Messages:
    2,896
    Likes Received:
    359
    Trophy Points:
    83
    Location:
    Norcross, GA - USA
    I guess I've been pretty fortunate. As a general principle I don't want to buy a phone that doesn't have a user replaceable battery but I have never needed to replace one and have managed to maintain runtime from the beginning to the end of life. (I usually keep them close to 2 years)

    But I also haven't used any or at least many of the tricks listed. I wait, if possible, until the phone is between 30% and 40%, (now and then much lower if I'm on the road), then charge to 100% but I don't charge overnight. My phones do stay on charge, most of the time, beyond the point of getting to 100% just because I'm not checking it so I don't know exactly when it happened and don't really care.
  9. FoxKat
    Offline

    FoxKat DF Super Moderator Staff Member Premium Member

    Joined:
    Apr 2, 2010
    Messages:
    8,610
    Likes Received:
    822
    Trophy Points:
    113
    Location:
    Pennsylvania
    Charging overnight shouldn't cause an issue. This used to be a BIG problem with Nickel Cadmium batteries, and much less of a problem with Nickel-Metal Hydride batteries, but the Lithium batteries don't suffer from the "memory" effect that constant charging would create. Our phones have circuitry that protects the battery from over-charging, and keeps it floating between 90% and 100%, and when it reaches 100% it stops charging, then monitors the current and voltage until it gets to 90%, at which time it resumes. In most cases if the phone is lying dormant, that may only happen once during the entire night, but if the phone is really laden with apps that check statuses of email accounts, facebook, other sync'ing processes, it could drain the battery enough to have it cycle in that range several times overnight.
  10. leeshor
    Online

    leeshor DF Super Moderator Staff Member

    Joined:
    Jan 30, 2012
    Messages:
    2,896
    Likes Received:
    359
    Trophy Points:
    83
    Location:
    Norcross, GA - USA
    I got in the habit of not charging overnight for what was once a really good reason and may still be. For the longest time I noticed data usage somewhere between midnight and 1 AM even though the phone was on WiFi & sleeping. I found that it ONLY happened when the phone was on the charger during that time. The data appeared to be usage information AT&T was pulling from the phone though I can't say that for a fact, but I did my research.

    Haven't seen that data use in the middle of the night since I stopped charging overnight.
Search tags for this page
battery swell galaxy s4
,
battery swelling
,
battery swelling reason samsung
,
battery swollen droid 4
,

droid 4 battery

,
droid 4 battery expanding
,
droid 4 battery swell
,

droid 4 battery swelling

,
droid 4 battery swollen
,

droid battery swelling

,
how to fix droid x battery swell
,
motorola droid 4 battery swelling
,
motorola droid 4 swollen battery issue
,
swelling battery
,
swollen cell phone battery in droid 4