The 'symmetrical' Note 7 design might be precisely why its batteries were failing

The Note 7 employs a lot of "firsts" for Samsung when it comes to the design, but these might be precisely the reason it is catching on fire, and had to be recalled twice now. For instance, Samsung employs the toughest 7000 series aluminum alloy for the frame and the sides - that would make it 1.3 times stronger and 1.2 times more scratch-resistant than the metal which is used for the Galaxy S7. Moreover, in order to leave the widest amount of flat space for the S Pen to draw on, Samsung employed a rare 3D thermoforming process, producing the steepest "edge" sloping of a curved display it's ever done, as you can see in the drawings here. Not only that, but Samsung bragged that the design is now absolutely "symmetrical," as the glass backplate is sloping towards the metal frame with the same curvature as the display at the front.

The steep glass curve makes the device the narrowest Note ever, even when compared to the first 5.3" one, and the narrowest phone with a 5.7" display, but it also might be precisely why the phone is combusting out of the blue. During the first recall, leaked docs from the Korean consumer protection agency showed that the battery packs made by Samsung's own SDI subsidiary were slightly larger for their compartment by a hair, and the isolation plates that separate the anode and cathode inside were too close towards the edges, hence prone to collapsing under pressure, short circuiting the battery, and causing thermal runaway. They also found issues with the packaging of the battery cells, like the insulating tape, which was done by a separate company, as well as the coating of the negative electrode.

While these issues taken separately might not produce the spontaneous combustion that the Note 7 is prone to, in aggregate they present a dangerous combo, especially if there was pressure applied on the isolation plates. Where would that pressure come from? Well, one of the theories seems to be that the culprit is precisely the steepest edge curve Samsung has ever done. The plates are apparently situated towards the edge of the battery, and, when sealing the waterproof phone tight, the pack might be subjected to a pressure that is higher than normal at the wrong end. Coupled with the production faults in the battery packs themselves, this could explain the first recall.

The second recall is a bit of a mystery, though. While leaked info shows that it is allegedly still a battery issue (duh), the replacement packs were reportedly produced entirely by ATL, hence they shouldn't have sizing, isolation plate, insulation, or negative electrode coating issues. The eventual abnormal pressure from the steeply curved sides remains, though, and that could be the design flaw that ate the Note 7's head. That, or a faulty voltage controller design, or the three weeks timeframe in which Samsung acknowledged the problem, and rushed ATL to produce hundreds of thousands of spare batteries for quick replacement. Well, as the jail writing says, those who are ahead of their time should wait for it at the designated places. In the case of the Note 7, it might very well be in the dustbin of electronics' history.

source: NYT, Bloomberg, FTSBS

Story timeline

Related phones

Galaxy Note 7
  • Display 5.7" 1440 x 2560 pixels
  • Camera 12 MP / 5 MP front
  • Processor Qualcomm Snapdragon 820, Quad-core, 2150 MHz
  • Storage 64 GB + microSDXC
  • Battery 3500 mAh



1. CoastCity

Posts: 257; Member since: Mar 07, 2014

It's only for show and product diversification. Sometimes it makes the use difficult (S7 edge, accidental touches) without adequate software improvement

3. TerryTerius unregistered

Having owned the S6 edge and now the S7 edge, accidental touches have rarely been an issue. With or without a case. The palm rejection software they built-in consistently does a good job. Granted, you do get used to holding your phone in certain ways.

29. Brewski

Posts: 725; Member since: Jun 05, 2012

I completely disagree. I have had the S7 edge since March and I hate it for that one reason. I use a Moto Turbo 2 as my daily driver and it is far superior. The S7 was given to to me by my work and it never leaves my desk holding papers down all day and all night. Every single time I pick up the phone it registers the edge touch. I have to hold it flat on my hand while I am sitting down or it exits out of an app I'm using or thinks I am trying to touch somewhere when I am just holding the phone reading an email. If the screen is on and I set the phone down it is impossible to pick it back up without it registering an edge touch. I let my friend borrow it for a week while he was sans phone and he practically threw it at me saying he never wanted to use it again. I agreed with him telling him that's why I let him use it because it is such a pain to use. I had already decided I would never purchase a Samsung phone again and now with the Note 7 battery issues this just cemented that fact. I will never own another Samsung device again.

31. TerryTerius unregistered

Cool. Hope you enjoy whatever you get next.

36. phonearenarocks

Posts: 607; Member since: Mar 26, 2015

Well! I second Terry, been using S6 Edge and faced no issue - and give the trophy to him based on the likes difference. Terry - Beers!

5. trojan_horse

Posts: 5868; Member since: May 06, 2016

^^ I too, I've not liked the curves of Samsung's 2016 flagships. The original curve of the Note Edge was much better, and the curves of the S6 Edge Plus is more pronouncd than the S7 Edge. This steeply curved sides needs to be modified in the next flagship!

8. TerryTerius unregistered

I guess that comes down to personal taste. I would vehemently disagree with you on that point but to each their own

2. Darckent

Posts: 98; Member since: Sep 17, 2016

Phonearena a well known apple bias fansite seem to be enjoying this battery issue of the note 7 Such an unprofessional site While your at it review all phones fairly reading your iPhone reviews compared to other phones which do more and bring more to the table is disgusting

7. TerryTerius unregistered

How exactly is it unprofessional for a mobile news site to report on news related to the largest phone company on the planet? I would agree that the unending barrage of articles could certainly be handled via longer & more well-thought-out pieces instead of posting all day long... but the practice of reporting facts in and of itself is not unprofessional. Well, aside from authors giving their personal feelings on Samsung which is frankly irrelevant and serves no purpose other than to stir up the beehive and get more clicks. They could definitely stop doing articles like that, whether that is about Samsung, Apple, or anyone else. That said, what exactly is fair? That is a pretty subjective term. Unless they strictly talked about nothing but objective performance parameters and left it at that, all reviews are subjective. It is basically asking somebody what their opinion is on a given product. If that is the basic premise, you have to accept that reviewers may disagree with your opinion on what makes a good phone.

10. NoToFanboys

Posts: 3231; Member since: Oct 03, 2015

Very well said


Posts: 63; Member since: Oct 11, 2016

That happens when you hire morons to write articles.

30. Aploine

Posts: 445; Member since: Oct 24, 2013

Pou ise re arpaktiko?

23. piyath

Posts: 2445; Member since: Mar 23, 2012

This is the news flash of the year.. Probably might be the news of the century. SO how can anyone not write about it. Are you kidding???

28. nctx77

Posts: 2540; Member since: Sep 03, 2013

People like you always say that BS, but fail to see various other sites reporting the same thing!

33. Nine1Sickness

Posts: 896; Member since: Jan 30, 2011

Phonearena readers are well known to be salty. If you want to only read articles that praises Android and Android devices, go elsewhere.

34. greyarea

Posts: 267; Member since: Aug 14, 2015

Feel free to not visit the site. You're complaints will not be missed.

4. piyath

Posts: 2445; Member since: Mar 23, 2012

Let's see what the Samsung engineers have to say about this problem in the comment section below... LOL

9. tangbunna

Posts: 491; Member since: Sep 29, 2016

they should replace with a new smaller battery at 2600mah and make more space to pack special matterial for heat-proof, burn-proof, leak-proof, short-circuit-proof, explosion-proof, water-proof and whatever proof. damn it.

17. AmashAziz

Posts: 2934; Member since: Jun 30, 2014

The comment section needs to be trollproof.....

11. tacarat

Posts: 854; Member since: Apr 22, 2013

At least now we know that the pretty edges are form over function. I wonder how long it'll be before they design around that, maybe even patent the fix or kaboom reduction tech?

14. Nine1Sickness

Posts: 896; Member since: Jan 30, 2011

I see, so the batteries were OCD.

15. Guaire

Posts: 893; Member since: Oct 15, 2014

I'm not sure if I have ever read such a BS article.

18. AmashAziz

Posts: 2934; Member since: Jun 30, 2014

Yeah, when you don't understand a single word, it becomes trash for you......nice, very nice !

24. Guaire

Posts: 893; Member since: Oct 15, 2014

It becomes trash when you have a clue.

19. acruzlu unregistered

By this author's logic shouldn't have all the other phone's mentioned have some kind of risk of failure?

20. AmirBudi

Posts: 88; Member since: Mar 21, 2014

"The eventual abnormal pressure from the steeply curved sides remains, though, and that could be the design flaw that ate the Note 7's head."

32. fiji.siv

Posts: 95; Member since: Nov 25, 2015

That entire last paragraph is a hot mess. "design flaw that ate the Note 7's head" - Ate the Note 7's head? WTF is that? "That, or a faulty voltage controller design, or the three weeks timeframe in which Samsung acknowledged the problem, and rushed ATL to produce hundreds of thousands of spare batteries for quick replacement." - Is that a complete sentence? Are you saying the 3w timeframe is the design flaw or what ate the head? I'd say it ate the head except it's paired with 'faulty voltage controller' which sounds like a design flaw but very well could be what ate the head according to the author. "Well, as the jail writing says, those who are ahead of their time should wait for it at the designated places." - Jail writing? What are you talking about? Where are these designated places?

26. dimas

Posts: 3419; Member since: Jul 22, 2014

Interesting. If samsung placed the battery at the center, could the battery's short circuiting be prevented?

27. Jeradiah3

Posts: 1149; Member since: Feb 11, 2010

Although I still think that its the battery, it could be the design as well.

* Some comments have been hidden, because they don't meet the discussions rules.

Latest Stories

This copy is for your personal, non-commercial use only. You can order presentation-ready copies for distribution to your colleagues, clients or customers at or use the Reprints & Permissions tool that appears at the bottom of each web page. Visit for samples and additional information.