iPhone Battery drops suddenly even when fully charged - Help!

I had the mostly the same issue after updating to 10.1.1 my battery drained very fast 100% in the morning and at ~4pm 35% without mobile date use etc. I don't know how I exactly solved the problem. I drained the battery to 0% tried a few times to start the phone until only the battery sign appeared. After that I charged the phone till 100%. After reaching 100% just let the phone 1 -2h plugged in. Now battery life time is normal again. What I recognized was while the battery drained so fast, battery time use (Settings>Battery) was empty still if I chareged to 100% .. It said load to 100% even if Ifully charged. Now everything is fine. Maybe this solution helps.

Sry for my bad English :/

I have this problem, too.

and This helps me find out that Apple Care service is really bad...

My Iphone 7plus 128gb bought since Nov 11, 2016, after using it for 3 weeks, I noticed that the battery got something wrong. So I tested it twice:

- with my normal using habit (ON for all notifications, location service, 30% brightness): 34% dropped to black screen in 6 hours at night.

- then the next day I turned off all the notifications, location service, turned on the low battery mode, 10% brightness: 23% dropped to black screen in 6 hours at night.

So, definitely it had something wrong so I brought it to local AppleCare service authorized by Apple and totally depressed:

- they asked me to open my iphone to check, . I let them open because they said if not, they could not check the issue.

- After open my iphone, they said: the phone is OK, not soak (***??? I DIDNT ASK THEM TO CHECK IF MY PHONE HAD SOAKED)

- then they said they need to check the software for battery, and the result is GOOD.

- finally, they asked me to leave the phone at the service to check overnight (***??? I THOUGHT THIS SHOULD BE THE FIRST STEP)

If the result is from the software, what should do with my already-opened-iphone ???

I have been using iphone since 4S. Totally disappointed.

Sorry for my bad grammar 😟

Hi there,

Well it looks like you have the same issue. I was at a TorontoFC soccer game and it was a WARM night, so I know this wasn't cold weather related as it happened in other conditions at home and work. I noticed my battery drop from 77% to 20% other day and today, I was at 55% and it dropped to 17%!. I am on 10.1.1 and not sure exactly when this started to happen but when I called Apple, I ran diagnostic while on phone and it sent data and they said my battery was ok on a 2014 Iphone 6 plus. I was thinking it was cold weather in past but there's something going on.

Apple support said they're sorry and they suggest I do a CLEAN INSTALL "from iTunes" (not from phone) to clean out completely. They've had similar reported cases but this seems to solve problem. Sometimes, there ARE issues when we do progressive updates from previous OS' to new version updates. That is, having 10.0, and then updating 10.1.1 or something like that. Thus, doing a full fresh install of 10.1.1 direct to phone may help. This kind of is painful BUT most of the stuff is backed up to iCloud (contacts) and other app data so thankfully not as bad as other platforms. In the end, I have way too many apps installed and some are hardly used and I have to be more militant with my apps as there's no doubt something is draining this in background even thought I have eliminated refresh and diagnostic logging and advertising and other things that log data in background.

I will give it a go and report back here.

I actually took mine to the Apple Store for the battery issue. They told me it was a software problem and the only way to fix it was to do a factory reset. It's been done 3 times and the only thing it accomplished was losing my ringtones. Battery is awful. I have to carry a charger everywhere I go. I have an iPhone 6.

Me too, and very lag apps. 😢😢😢

Sao không ra bên fpt ấy.

ra rồi, FPT nói bên đó ko bảo hành, mà bên đó sẽ giúp khách hàng chuyển qua Apple Care, nên nếu KH muốn nhanh thì đem thẳng ra đó, bởi vậy mình mới đem thẳng ra Apple Care