Battery drops from ~35% to 0% instantly

[RyMac04]

For the past two nights my s7 edge has suddenly died. Out of nowhere. From around 35% to 0% instantly. No new apps have been installed.

When I plug it in, the battery charges up from 0%.

Check out the screenshot. Any solution to this? About a 2 year old s7 edge.

 

[chanchan05]

For the past two nights my s7 edge has suddenly died. Out of nowhere. From around 35% to 0% instantly. No new apps have been installed.

When I plug it in, the battery charges up from 0%.

Check out the screenshot. Any solution to this? About a 2 year old s7 edge.

It's a 2 year old battery. You need a new one.

 

[RyMac04]

It's a 2 year old battery. You need a new one.

Fair - but I would simply expect faster drain if the battery was a problem.

I can't understand why it's normal battery life and then suddenly dead?

 

[chanchan05]

Fair - but I would simply expect faster drain if the battery was a problem.

I can't understand why it's normal battery life and then suddenly dead?

Batteries don't degrade the same way. It could be a circuitry problem inside the battery that cuts power when it reaches that voltage point.

 

[Mooncatt]

Fair - but I would simply expect faster drain if the battery was a problem.

I can't understand why it's normal battery life and then suddenly dead?

All batteries, regardless of type will experience something called voltage sag. Heck, you even see this with your AC power for your home when the lights dim for a split second whenever something like the air conditioning kicks on and draws a lot of power.

In short, any time a demand is placed on the battery, the voltage will drop for a bit. This is natural and to be expected, but the amount of voltage loss is minimal on a healthy battery. As a battery ages and the internals breakdown, the amount of voltage loss increases. The amount of demand you put on the phone affects this as well. I.e. Gaming would result in more of a voltage sag than just sitting idle.

What makes Li-ion batteries unique is that they can not be discharged to 0 volts and then recharged (at least not without special care and equipment, and even then it's not guaranteed). 0% on your battery gauge is not zero voltage. It's the lowest the battery can go and still be safely recharged.

So what you are experiencing is what happens when these two issues intersect. As your battery gets low, something is putting a power demand on the weakened battery that causes the voltage sag to dip below the cutoff point. When this happens, it's an instant shutdown as if you pulled the battery. This usually isn't noticed at first because it may start at 5% or so, which most people would've already plugged in before then. It'll only get worse from there. So you keep using your phone not knowing this is getting worse and worse, except maybe for shortened usage time between charges, until it finally starts sagging so much that the cutoff happens before you'd plug it in.

Hopefully this helps clear it up for you. As a side note, this instant shutoff is what Apple was trying to avoid when they started slowing down their phones with weak batteries. By throttling performance, the voltage sag wouldn't be as bad, letting you keep using the phone longer without the instant shutdown. Not that this is necessarily a good thing, as Li-ion batteries hate being deeply discharged and letting people keep doing so like this could actually speed up the degradation.

 

[RyMac04]

Wow. Thank you MoonCat. That's really interesting and informative. Now I know.

 

[Mooncatt]

Wow. Thank you MoonCat. That's really interesting and informative. Now I know.

"And knowing is half the battle."

...I couldn't help myself. XD

 

[neddyuk]

I have been getting exactly the same problem and mine is about 22 months old now shame its not like the old days in just swapping the battery by unclipping the back cover now you have to play with heat guns and adhesive.:-\

 

[jimjonesG7]

So whats the solution??? by mid-day my edge battery life is 50% always have to take my charger and charge at least twice a day to get through a full day

 

[Mooncatt]

So whats the solution??? by mid-day my edge battery life is 50% always have to take my charger and charge at least twice a day to get through a full day

For the OP, the solution was pretty obvious that he needed to replace the battery. Is yours also shutting off before hitting zero on the battery gauge? If so, then the same applies to you. If you are noticing increased battery drain but haven't had it shut down early on you, then it's a little more tricky.

Sure, it very well could be that the battery is bad. Especially if it's over a year old, has been repeatedly drained below 20%, held at levels above 75% (I.e. Overnight charging), or exposed to excessive heat. It could also be new/updated apps are simply using more resources to run and the only option there would be to uninstall them or deal with it. It could also be something buggy in the system needing a system cache clear, or a rogue app needing a cache or full data clear.

 

[RyMac04]

FWIW I've seen improvement after wiping the cache partition. But certainly I still need a new battery/phone.

 

[natehoy]

So whats the solution??? by mid-day my edge battery life is 50% always have to take my charger and charge at least twice a day to get through a full day

Best option: Replacing the battery with a brandy-new one. $20-30 for the battery itself, some tools to make it easier, and a couple fairly risky (!) hours of effort and bam! new battery life. Not for the faint of heart, and may never be water resistant again, but doable. Spend some extra on one of the really well-reviewed ones, your labor is the real cost here!

https://www.ifixit.com/Teardown/Samsung+Galaxy+S7+Teardown/56686


Short of replacing the battery, you can add a battery case.

Cost: About $30-50 on average.
Advantage: Will give you long battery life before your internal battery even starts to discharge, no risk of damage to your phone by ripping it apart to get at the battery.
Disadvantage: Makes your device bigger and heavier, keeps your internal battery at 100% while in use so it degrade slightly more quickly.


You can also get a wireless charging pad for work, so all you have to do is drop the phone on it rather than plugging it in all the time. You may find that more convenient, at least...


Or of course there are battery packs, but that means you are carrying around your phone, a cable, and a battery pack. A decent alternative if you need to be in meetings a lot during the day. It's the cheapest option and very effective if you don't mind walking around with a cable plugged into your phone and leading in to your pocket or backpack.

Or, sort of a hybrid solution, a few companies make QI wireless charging battery packs - so you can have a no-cables way to add some charge to your phone where outlets might not be conveniently available. Pull out the battery pack, turn it on, and set your phone on top of it.

 

[Minion Mangala]

Thank for the extensive explanation. You sir deserve an award for the time you took to write that comment.

 

[punk999]

Hi, was this problem solved for you? I'm having the exact same problem, battery reaches 30% and drains rapidly to 0%

 

[chanchan05]

Hi, was this problem solved for you? I'm having the exact same problem, battery reaches 30% and drains rapidly to 0%

Same solution. Basically get a new battery. It's a hardware issue, not something any tweak can fix.

 

[testtesttesttesttesttesttest]

It is not a ""normal wear and tear". If it was it, it wouldnt get from 35% to 0. it would start with 10, 15 20 etc.
thats firstly.
And secondly, there is something called planned planned obsolescence. Samsung strategy is following:
We will make an awesome device which blow people away. But they put batteries which doesnt last that long. Fortunately its not something like some companies *cough* do with their updates and slow down their devices. but anyway.
Unfortunately for you and all samsung users, only way is to switch phone or replace battery. happens with my s8 and irritates me too. But its not just lifespan of battery. I had galaxy S4 for 5 years, and i didnt replace its battery (good ol easy battery switch times). back then samsung was hungry for reputation, but now they are hungry for money......

 

[belodion]

It is not a ""normal wear and tear". If it was it, it wouldnt get from 35% to 0. it would start with 10, 15 20 etc.
thats firstly.
And secondly, there is something called planned planned obsolescence. Samsung strategy is following:
We will make an awesome device which blow people away. But they put batteries which doesnt last that long. Fortunately its not something like some companies *cough* do with their updates and slow down their devices. but anyway.
Unfortunately for you and all samsung users, only way is to switch phone or replace battery. happens with my s8 and irritates me too. But its not just lifespan of battery. I had galaxy S4 for 5 years, and i didnt replace its battery (good ol easy battery switch times). back then samsung was hungry for reputation, but now they are hungry for money......

Welcome.

I don't believe that any manufacturers do that. Android Central would deprecate such claims, unless backed by proof.

This is also relevant to this thread: https://forums.androidcentral.com/showthread.php?t=500054

 

[Mooncatt]

If it was it, it wouldnt get from 35% to 0. it would start with 10, 15 20 etc.
thats firstly.

Already explained in my comment above.

And secondly, there is something called planned planned obsolescence. Samsung strategy is following:
We will make an awesome device which blow people away. But they put batteries which doesnt last that long.

Conspiracy theory at best. If this were the case, there would be a lot more complaints about it.

Fortunately its not something like some companies *cough* do with their updates and slow down their devices. but anyway.

Also already explained in my comment.

Unfortunately for you and all samsung users, only way is to switch phone or replace battery.

Not just Samsung, but all brands. No one makes a forever battery.

back then samsung was hungry for reputation, but now they are hungry for money......

All companies are hungry for money. It's why they are called a business and not a charity.

 

[RyMac04]

OP here... It's interesting re-reading this a year later on a galaxy s9+ with 21% left after 14h and 23m of use today.

No, they don't make batteries that last forever. But they've sure made ones that last all day and then some. As discussed, the issues with your batteries can mostly be attributed to simply being old. That was the case with mine.

 

[ragnarok687]

OP here... It's interesting re-reading this a year later on a galaxy s9+ with 21% left after 14h and 23m of use today.

No, they don't make batteries that last forever. But they've sure made ones that last all day and then some. As discussed, the issues with your batteries can mostly be attributed to simply being old. That was the case with mine.

My Galaxy S9 has recently suddenly starting dying when it hits 30% battery remaining. I've only had it for 15 months, and in fact had a repair carried out under warranty after 9-10 months of ownership. Samsung ran a battery diagnostic on it and said it had only lost 3% of original battery condition, which I put down to my strict regime of only letting the battery deplete down to 30%, then charging to about 80% max as this was the recommended charging regime.

Fast forward 6 months and this forum seems to be saying that I've gone from 3% degradation to my battery being practically junk?! What a rip! I'd kinda hope that after forking out £700 on a handset and carefully protecting the battery that it would last at least two years! With my old Galaxy S4 that lasted 5 years and I only swapped the battery once.