Two battery defects caused Galaxy Note 7 explosions

Scorpus

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Samsung's full investigation into their issues with the Galaxy Note 7 has blamed two major battery defects as the root cause of numerous device explosions that lead to a worldwide recall. After testing more than 200,000 defective devices with the help of 700 dedicated staff, Samsung identified specific issues with the design and manufacturing of these batteries, but claimed there were no issues with the rest of their smartphone's hardware or software.

In the first set of batteries, manufactured by Samsung SDI, there was a flaw in the upper right corner of the battery that caused a deflection in the negative electrode. This deflection led to a short circuit, which caused fires and explosions in some cases. Samsung also identified a secondary issue where the negative electrode was incorrectly located in the curve of the battery.

After the initial recall of Galaxy Note 7s with Samsung SDI batteries inside, Samsung switched to a new supplier, Amperex Technology (listed as "Battery B" in Samsung's press release). This supplier had issues ramping up production to meet demand, and inadvertently introduced a manufacturing defect during this ramp-up process. The defect, introduced as the batteries were being welded, led to the positive tab short circuiting with the negative electrode. Again, this caused fires and explosions.

It's possible that Samsung was just unlucky that both battery suppliers produced batteries with defects. It's more likely that Samsung's battery validation and quality control procedures were inadequate, leading to these issues going undetected until Note 7s hit the hands of consumers.

For all future smartphones, Samsung will be using a new eight-step battery validation procedure, that expands upon their previous testing and introduces several new tests. Part of this new procedure will involve actually powering up and down finished handsets, which is something the company didn't do previously. Samsung will simulate two weeks of "real life" battery usage in five days as well, to test for any issues during normal usage.

Samsung will now work to rebuild trust in their smartphones, and the depth of this investigation, plus their public explanation of their battery issues, should help matters somewhat. 

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Cool, well... Good to hear, but... After they simulate two weeks of battery testing on the handsets, I think I'll wait an additional 2 months before considering buying a Samsung smartphone!
 
That's all in the past now and I hope that they learned their lesson that profit isn't the be all and end all of everything. I'll still drop my dough on their products in the future without much too much hesitation, I've never bought one of their products that I haven't been satisfied with. It's a good thing I was never a Note series fan otherwise things could've been different.
 
AllAboutCircuits did their own teardown and investigation of a good number of Note7s, and found that they also had a design flaw: batteries too large for their compartments. All rechargeable batteries expand and contract during their normal charging/discharging cycles. Their compartments are supposed to have the clearances for this. In Samsung's pursuit of the thinnest phone with the biggest battery, they trimmed these clearances too much, so that as the battery expanded and contracted, the anodes and cathodes were forced together to create short circuits. This is probably why Samsung immediately said to stop charging your phone, but didn't seem to care if you left them on - they probably suspected the cause of the issue.

This seems to fit with Samsung's report, but Samsung's report still tries to hide that they screwed up. If those defects existed due to manufacturing, the devices would have been catching fire in the factory and immediately upon first charging - which happens before they put in box and shipped out, completely drained lithium batteries require very specialized charging equipment. Instead, it is more likely that these are the flaws that came about from not having the necessary clearances in the battery compartment, and how the flaws differed between the two batteries.
 
And, I think Sammy was partly to blame, for trying to "one up" Apple. When it was pretty clear how big the battery in the iphone was going to be, Sammy told the engineers to put a bigger battery into the Note7.
Again, if manufacturers would STOP making phones "stylish" and just make them a little thicker, this crap wouldn't happen. The non removable battery is a direct result of this "thin is in" crap. By eliminating the removable battery, they can use the room that is taken up by the plastic casing around the battery, the contacts and what not, for a slimmer design, and stuff as much battery as they can into that given area. When a battery has the slightest flaw in design, coupled with a super thin design, that people constantly shove into their skinny jeans, then sit down and get up a few dozen times a day, the thin case flexes, and before you know it POOF!
 
This seems to fit with Samsung's report, but Samsung's report still tries to hide that they screwed up. If those defects existed due to manufacturing, the devices would have been catching fire in the factory and immediately upon first charging
Bro do you even read? They even put pretty pictures for you...

Ok @koblongata and @Puiu, was it the fundamental design flaw... or the battery????
 
Bro do you even read? They even put pretty pictures for you...

Ok @koblongata and @Puiu, was it the fundamental design flaw... or the battery????
do you honestly believe that the "rounded" batteries made by SDI were made like that without Samsung having a hand in it's design? from the shape to the thickness and weight, everything was done by Samsung.
the 2nd manufacturer might be to blame for the manufacturing defects (missing protection, etc), but don't go having naive thoughts about the other things.
TL;DR it's not just the battery, it's the overall design of the phone that was flawed. they tried to make as thin and as light as they could and took too many risks.
 
In the first set of batteries, manufactured by Samsung SDI, there was a flaw in the upper right corner of the battery that caused a deflection in the negative electrode. This deflection led to a short circuit, which caused fires and explosions in some cases. Samsung also identified a secondary issue where the negative electrode was incorrectly located in the curve of the battery.
do you honestly believe that the "rounded" batteries made by SDI were made like that without Samsung having a hand in it's design?
Ok I'll bite, but was it the "phone"'s design flaw or... the battery???? Which was always the point...
 
Funny how an independent test of this issue showed that the batteries were actually fine, but that Samsung built the battery covers too close, not allowing the natural slight bulging of the battery throughout the day. Not surprised Samsung is trying to shift the blame away from themselves.
 
Funny how an independent test of this issue showed that the batteries were actually fine, but that Samsung built the battery covers too close, not allowing the natural slight bulging of the battery throughout the day. Not surprised Samsung is trying to shift the blame away from themselves.
Yes, it makes you wonder how a 200.000 units sample along with 700 dedicated people can compete against an independent small group of people testing.
 
Poor ATL, made their success from making batteries for Apple for years and then BOOM everything blew up with the partnership with Samsung for the first time.
 
Don't think I remember hearing about one of those things exploding.
lots overheated, many even caught fire. but exploding? links?
 
Yes, it makes you wonder how a 200.000 units sample along with 700 dedicated people can compete against an independent small group of people testing.
Can you imagine Samsung coming up with "sorry guys, we thought expanding batteries was just a hoax…"?
 
Ok I'll bite, but was it the "phone"'s design flaw or... the battery???? Which was always the point...

It is both. You can't design any one part of a system in a vacuum, separate from the system as a whole. Samsung made the battery compartment too small for the battery I.e. some project manager for the Note7 told the battery team "AxBxC" mm dimensions, and didn't make it clear whether those dimensions included the clearances or not, or they told the mechanical team that the battery would need "AxBxC" mm, and again did not make it clear if that included clearances or not. Or they knew they were cutting the tolerances tight, but I doubt this. AllAboutCircuits described it as a 'rookie' mistake, and you don't use that language when looking at solution an engineer who was trying to be clever came up with. It was either poor communication between teams/management, or the loss of talent who actually knew what they were doing (replaced with someone who didn't).

AllAboutCircuits is another tech blog, dedicated to electrical engineering, they employ electrical engineers who write about their specific areas of expertise. If they say the Note7 phones they pulled apart had battery compartments too small for their batteries, I believe them over Samsung in this case. Samsung disclosed what the defects were, but if those defects existed from the manufacturing of the battery, they would have been catching fire in the factories - Samsung would have known from the start that the phones were a mass recall waiting to happen. Instead, it is more far likely those are the defects that arise from the charging cycles the phone naturally goes through.

Samsung screwed up - they screwed up their project management, the design, the recall, the re-design, and re-recall - and now they are still trying to hide the exact cause by only telling half of the truth. Get over it.
 
It is both. You can't design any one part of a system in a vacuum, separate from the system as a whole. Samsung made the battery compartment too small for the battery I.e. some project manager for the Note7 told the battery team "AxBxC" mm dimensions, and didn't make it clear whether those dimensions included the clearances or not, or they told the mechanical team that the battery would need "AxBxC" mm, and again did not make it clear if that included clearances or not. Or they knew they were cutting the tolerances tight, but I doubt this. AllAboutCircuits described it as a 'rookie' mistake, and you don't use that language when looking at solution an engineer who was trying to be clever came up with. It was either poor communication between teams/management, or the loss of talent who actually knew what they were doing (replaced with someone who didn't).

AllAboutCircuits is another tech blog, dedicated to electrical engineering, they employ electrical engineers who write about their specific areas of expertise. If they say the Note7 phones they pulled apart had battery compartments too small for their batteries, I believe them over Samsung in this case. Samsung disclosed what the defects were, but if those defects existed from the manufacturing of the battery, they would have been catching fire in the factories - Samsung would have known from the start that the phones were a mass recall waiting to happen. Instead, it is more far likely those are the defects that arise from the charging cycles the phone naturally goes through.

Samsung screwed up - they screwed up their project management, the design, the recall, the re-design, and re-recall - and now they are still trying to hide the exact cause by only telling half of the truth. Get over it.

Wait, they screwed up the re-recall? Urmmm... How?
 
Wait, they screwed up the re-recall? Urmmm... How?
They still don't have all the Note7s back, and people are refusing to return them. They tried to do it unofficially at first, by contacting consumers directly without involving regulatory agencies like the CPSC. They failed to properly differentiate the issue as Note7-specific to the general public, and information was so poorly disseminated that airlines gave out blanket bans on all Samsung devices. When the replacements started catching fire as well, Samsung tried to buy off the people with those devices (and got caught doing so) - while continuing to ship the replacements.

If that isn't a botched re-recall, I don't know what is. The first time was botched because they only recalled a small portion of affected devices, and the solution didn't actually work. The second time was botched because they tried to hide how badly they screwed up from consumers, and started a PR and liability sh!tstorm as a result. They were the victims of their own hubris and pride.
 
They still don't have all the Note7s back, and people are refusing to return them. They tried to do it unofficially at first, by contacting consumers directly without involving regulatory agencies like the CPSC. They failed to properly differentiate the issue as Note7-specific to the general public, and information was so poorly disseminated that airlines gave out blanket bans on all Samsung devices. When the replacements started catching fire as well, Samsung tried to buy off the people with those devices (and got caught doing so) - while continuing to ship the replacements.

If that isn't a botched re-recall, I don't know what is. The first time was botched because they only recalled a small portion of affected devices, and the solution didn't actually work. The second time was botched because they tried to hide how badly they screwed up from consumers, and started a PR and liability sh!tstorm as a result. They were the victims of their own hubris and pride.

As I see you making some valid points here, I have to say that some of this is out of their control and just not true.

"On 2 September 2016, Samsung suspended sales of the Galaxy Note 7 and announced an informal recall"

This was before everyone realized it wasnt an isolated event. Sure, it's informal and they should have reported it, but if you have 1 device out of 1,000,000, it's not legally required until they deem it a defect of the product and not the environment.

"On 12 September 2016, the Galaxy Note 7 was officially recalled in the U.S. by the Consumer Product Safety Commission"

They filed 10 days later... Sure, I mean, they could have handled it better... but every company could have done SOMETHING better.

They can't force people to return them. They don't have control over what the airlines ban. The rest of the things I dont address, well... I guess I don't care enough to look up and verify everything.

If I'm wrong about any of this please feel free to link me to corresponding articles, I'm not a complete *** and can admit when I'm wrong or looked something up incorrectly.

Now, I may be somewhat of a Samsung fanboy, but I've also already commented that their reputation and quality control has been damaged in my eyes, and that I will be reluctant to buy a new Samsung handset for awhile, but some of what you say just doesn't seem to be quite true, or is just unreasonable blame, that's all. Please inform me.
 
Yes, it makes you wonder how a 200.000 units sample along with 700 dedicated people can compete against an independent small group of people testing.
700 dedicated biest people, hired by the company that made the mistake
vs
an unbiest organization with an undetermined amount of units to test
hmm indeed.
 
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