Phone shut off at 17% is the battery failing?

[Lucy Davies]

My phone battery was at 17% & I wanted to get the battery a bit lower then charge it so I launched Pokemon go & the game was struggling to find my location so I decided to exit the game but as I did that the game found my location so I re entered the game & all I got was a black screen then I had a battery icon appear with really low battery so I plugged in my power bank & the battery icon came up again looking completely empty then a few seconds later it came up saying 19% charged so I turned the phone on & it stayed on the Motorola powered by android screen for ages (I thought the phone was stuck on that screen) then it booted up fine. Then on the home screen I noticed one of my apps had removed itself but it was still in the app draw.

Battery has been fine since but I'm worried incase it does it again at 17%. Any idea what happened?

 

[doogald]

That sounds a lot like the infamous iPhone battery problem reported in the last few weeks, which Apple has been getting heat for throttling the phone to prevent it shutting down when the battery still has life left but can't supply enough voltage. I'd suggest charging the phone when it starts getting to, say, 30% or lower, since Motorola is unlikely to do the same thing that Apple did.

 

[Ry]

I agree with doogald.

 

[Lucy Davies]

I read that bit about Apple & a few days after Motorola said they don't do that. I no my battery isn't what it use to be on this phone but I need it to last until I upgraded but no idea what phone I'm gonna get.

 

[Lucy Davies]

Phone done it again tonight. Battery stayed at 21% for the 4 hours I worked then shut itself off at 19% when I went to read Twitter. What is happening to this battery?

 

[Lucy Davies]

Phone is getting worse I swear. I touched an app & the phone shut down again at 26% when I powered it back on the battery was still at 26%. What is going on?

 

[doogald]

I read that bit about Apple & a few days after Motorola said they don't do that. I no my battery isn't what it use to be on this phone but I need it to last until I upgraded but no idea what phone I'm gonna get.

What Apple does is temporarily slow down the phone so that when something running on the phone needs so much battery that it would cause the phone to shut down, because the battery cannot supply enough voltage to keep the phone running, it will slow down the processor, which reduces the amount of voltage required from the battery, and keep the phone running.

Motorola doesn’t do that, so rather than the phone continuing to run, because the battery cannot supply enough power at that moment, even though there is still available charge, the phone must power down. When you power back up, you find that there is still available battery percentage, but the same thing will keep happening if the phone requires more power than the battery can supply.

This happens when batteries get old (or cold - it can happen to a new battery when the phone is running when it is exposed to extremely cold temperatures.) You are describing exactly the thing that Apple was preventing by slowing down the phone temporarily and had everyone upset (as if having your phone shut down unexpectedly is better than having it continue to run, just a little bit more slowly.)

Sorry to say that if this is what is happening to you, and it sounds like it is, the answer is to try to keep the battery more charged if you can, somehow get the battery replaced, or, of course, move on to another phone. When phone batteries get about two years old or so, this starts happening.

 

[Lucy Davies]

I am due to upgrade my phone next month but I may wait a little longer coz the HTC U12 looks really nice so may go for that.

 

[LeoRex]

Yep... When your phone powers down like that, it's because the battery is no longer able to provide consistent power. If that happens at 17%, that is a telltale sign that the battery is showing signs of degrading.

 

[Lucy Davies]

Is there a way to slow the degrading down?

 

[doogald]

Is there a way to slow the degrading down?

No, it’s only going to get worse. However, if you keep your phone charged - plug in more often - you shouldn’t see the shutdowns quite as often if at all. With a quick charger , 5-10 minutes should be able to give quite a boost. Or even carry an external battery pack around and plug in the phone occasionally when it’s in your bag/pocket/etc. I’d say the goal is to keep it above 50 to 60 percent as much as possible.

 

[Lucy Davies]

Well my phone did well when I was at work only loosing 2% which is the least it's lost as I normally looses about 8%. The phone came with a turbo charger which I use to charge the phone & I have 2 power banks which I carry around coz I love playing Pokemon go. So far the phone hasn't shut down for nearly a week. Not doing anything different either. Wonder what's happening?

 

[Lucy Davies]

My supervisor at work thinks it's a good idea to let phones go to 0% then give it a 12 hour charge especially if it's a new phone. Is this true?

 

[LeoRex]

My supervisor at work thinks it's a good idea to let phones go to 0% then give it a 12 hour charge especially if it's a new phone. Is this true?

Draining to 0% is kind of like waiting a little longer than you should to change your oil... If you do it every once in a while, you are fine. Do it every cycle and your engine might not last a long as it should.

 

[Lucy Davies]

But I heard that draining to 0% was bad for the phone. I've always charged my phone when it tells me at 15% & always had good battery life apart from when the phone is getting to two years old. Should I try it with this Moto X Force which is 23 months old? Maybe it will stop turning off between 26 & 15%?

 

[Mooncatt]

Li-ion batteries do not need to be fully cycled, and draining to zero will degrade it quicker. Your boss is probably thinking of NiCad batteries and such that do need full cycles.

Discharging even to 15% is still doing damage to it. These batteries should not be discharged below 40%, 20% at the least. They prefer a happy medium of being 40-75% charged for the greatest longevity.

 

[Lucy Davies]

Well my supervisor is letting her phone go to 0% then giving it a 12 hour charge over night. She has a Samsung phone I think it's the S7 or S8. I told her about not doing that but she strongly disagrees with me. So phones should be charged around the 20-40% mark not 15 like I thought.

 

[Mooncatt]

Well my supervisor is letting her phone go to 0% then giving it a 12 hour charge over night. She has a Samsung phone I think it's the S7 or S8. I told her about not doing that but she strongly disagrees with me. So phones should be charged around the 20-40% mark not 15 like I thought.

Charging at 40% and unplugging at 80% is the generally accepted guideline to balance longevity and runtime between charges. If you want the max longevity without worrying about the runtime between charges, then keep it between 65-75% (which is often admittedly not practical). This article goes into great detail on the care and charging habits of Li-ion batteries. Not that I'd suggest you debate a stubborn boss, but it may be worthwhile for him to read too.

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

 

[doogald]

My supervisor at work thinks it's a good idea to let phones go to 0% then give it a 12 hour charge especially if it's a new phone. Is this true?

No. Completely wrong. Lithium based batteries do not like being close to 0%.

How to Prolong Lithium-based Batteries - Battery University

Similar to a mechanical device that wears out faster with heavy use, the depth of discharge (DoD) determines the cycle count of the battery. The smaller the discharge (low DoD), the longer the battery will last. If at all possible, avoid full discharges and charge the battery more often between uses. Partial discharge on Li-ion is fine. There is no memory and the battery does not need periodic full discharge cycles to prolong life. The exception may be a periodic calibration of the fuel gauge on a smart battery or intelligent device.

[edit] Sorry for the duplicate of @Mooncatt - I responded before I scrolled through all the replies....

 

[doogald]

Well my supervisor is letting her phone go to 0% then giving it a 12 hour charge over night. She has a Samsung phone I think it's the S7 or S8. I told her about not doing that but she strongly disagrees with me. So phones should be charged around the 20-40% mark not 15 like I thought.

Honestly, the more often you can give a small charge, the better. Plug in for a few minutes while have a tea or coffee break. Plug in while you are in the shower. Plug in while you are washing up for bed. If you drive somewhere, plug in, at least for part of the trip. (The only exception to any of these is if the phone is already fully charged.)

This is particularly true in your case, if your phone is having periodic shutdowns while it's reporting adequate battery charge.

I'd also say that Pokemon Go Time is a perfect time to keep it plugged in to a power bank, unless it would be terribly inconvenient to carry the phone that way. As to why it is different, when it was shutting down a lot, was it colder outside than it is now? Cold temperatures can cause the battery to work even harder (though you would think that it would be better to help cool the battery pack, really cold, like under -5C, can really stress the battery pack (as I have learned on my morning runs lately; if I forget to put it in an inner pocket under some layers, and instead leave it in an outer pocket, when I get back my phone can be as low as 65% rather than the typical 90%, and I can watch it fall 1% every 15 seconds until it warms back up.)