EEVBlog video idea... Make a Galaxy Note 7 catch fire.......

[Smokey]

Get your hands on one.  Check out the battery circuitry... Then stress it and see if you can get it to blow up.  That would get a TON of youtube hits.

[Brumby]

With a couple of million Note 7's and only a few dozen failures, the odds aren't good.... and anything you did to 'encourage' the failure would simply neutralise any conclusions you might come up with, since the failure did not occur under normal use.

[EEVblog]

With a couple of million Note 7's and only a few dozen failures, the odds aren't good.... and anything you did to 'encourage' the failure would simply neutralise any conclusions you might come up with, since the failure did not occur under normal use.

Yep.
Same thing with the Hoverboards catching fire. It would be like finding a needle in a haystack.

[EEVblog]

Finding the cause would be quite an achievement though.

The cause is imperfections in the battery manufacture. Finding it exactly require tearing down countless units and having intimate access to the manufacturing line.

[retiredcaps]

A more generic and likely timeless video topic would be something like

What makes a "battery" catch on fire?

This could be applied to cell, laptop, etc batteries.  Dave could explain all the complexities of

- charge circuits
- battery chemistry
- manufacturing tolerance
- fail safe operation
- shielding
- heat
- abuse
- etc, etc

[Smokey]

There is a chance that there just wasn't enough design margin on something.  Maybe a little overvolt is all it takes.  Or they used a cheap protection circuit or something.  Hook it up to a meter and see the actual charge voltages and currents and what the profiles look like.
If nothing else it would be interesting to see how much abuse the battery system could actually survive.

::EDIT:: At this point Dave is kind of the internet battery expert anyway...

[Smokey]

A more generic and likely timeless video topic...

Timeless???  You gotta be kidding!!  Ride the wave.  Title the video:
"10 things you didn't know about the Galaxy Note 7 battery that could kill you RIGHT NOW!"

[retiredcaps]

A more generic and likely timeless video topic...

Timeless???  You gotta be kidding!!  Ride the wave.  Title the video:
"10 things you didn't know about the Galaxy Note 7 battery that could kill you RIGHT NOW!"

That depends if Dave is an ambulance chaser or not.  Certainly, he could have way more views if he did more pop culture technology/electronics with click bait titles.  If he did though, he might find a certain portion of his core viewership leave and replaced with questionable supporters.

[Refrigerator]

How about we send one to the Hydraulic Press Channel ?

[Red Squirrel]

That would actually make a cool video, to do a teardown and speculate on what the cause may be.  I imagine it would be hard to find if it's a software fault though, but could maybe monitor it while it's charging or discharging to look for any weird spikes in voltage or current.

May need to rent a bomb shelter for this one. 

[EEVblog]

Timeless???  You gotta be kidding!!  Ride the wave.  Title the video:
"10 things you didn't know about the Galaxy Note 7 battery that could kill you RIGHT NOW!"

That would actually work 

[EEVblog]

That would actually make a cool video, to do a teardown and speculate on what the cause may be.

Probably would if I had one.

[station240]

That would actually make a cool video, to do a teardown and speculate on what the cause may be.

Probably would if I had one.

I'd imagine the post office wouldn't let anyone post one to you.



http://www.abc.net.au/news/2016-10-12/samsung-ceases-note-7-but-unlikely-to-suffer-permanent-damage/7924972

It may be fair to ask why Samsung didn't pick up the problems with the battery during their testing of the devices. Of the 2.5 million devices shipped, there have been around 100 cases of batteries catching fire and so that is essentially 1 in every 25,000 devices shipped.

Given that Samsung must have had more than 25K of these phones in one place before they were sold, it's clear you have to start using the device before it can fail.

http://www.nytimes.com/2016/10/12/business/international/samsung-galaxy-note7-terminated.html?_r=0

When several Samsung Galaxy Note 7 smartphones spontaneously exploded in August, the South Korean company went into overdrive. It urged hundreds of employees to quickly diagnose the problem.

None were able to get a phone to explode. Samsung’s engineers, on a tight deadline, initially concluded the defect was caused by faulty batteries from one of the company’s suppliers. Samsung, which announced a recall of the Note 7 devices in September, decided to continue shipping new Galaxy Note 7s containing batteries from a different supplier.

The solution failed. Reports soon surfaced that some of the replacement devices were blowing up too. Company engineers went back to the drawing board, according to a person briefed on the test process who spoke on the condition of anonymity because the internal workings were confidential. As of this week, Samsung’s testers were still unable to reproduce the explosions.

Samsung cannot even get the phones to blow up in the lab, what chance has Dave got ?

[EEVblog]

I would have thought that once a charging circuit was proven it would be changed infrequently given the risk reward ratio.

No charging or protection circuitry can stop thermal runaway in a LiIon battery if it's susceptible by design/manufacture. i.e. an internal short/process that causes thermal runaway by nature of the exothermic process.

[EEVblog]

Samsung cannot even get the phones to blow up in the lab, what chance has Dave got ?

None.
Best I could do is put a nail through it (which is actually an industry standard test) and then waffle on about exothermic reactions, maybe with thermal camera running.
https://www.tuv-sud-america.com/uploads/images/1392328973947243720521/designing-meaningful-lithium-ion-abuse-tests.pdf
http://energy.gov/sites/prod/files/2014/03/f13/es142_sriramulu_2013_p.pdf

[Bud]

Noone seems to be talking about analysis of what apps were on the failed phones. I think it is not only the battery charge rate but also discharge rate that needs to be analyzed. My iPhone 5 for example gets as hot during use as when it is charged.  E.g. Clearly, this happens when browsing java bloated web sites. It could be a weird combination of applications causing some sort of power glitches even in turned off state. Just thinking.

[nctnico]

I would have thought that once a charging circuit was proven it would be changed infrequently given the risk reward ratio.

No charging or protection circuitry can stop thermal runaway in a LiIon battery if it's susceptible by design/manufacture. i.e. an internal short/process that causes thermal runaway by nature of the exothermic process.

I read in a news article that the original battery got compressed which caused a short in some cases. With the newer batteries they don't know what is wrong but it is a different problem. Either way it seems Samsung has pushed the boundaries of technology too far.

[EEVblog]

I read in a news article that the original battery got compressed which caused a short in some cases. With the newer batteries they don't know what is wrong but it is a different problem.

It's either:
- bending/compression causing physical damage and internal short
- Overcharging causing internal short due to some unknonw chemisty/manufacturing thing
- Other manufacturing issue from the get-go leading to a short. The units that have failed are right on the edge of the manufacturing bell curve.

All roads lead to an internal short.

[Don Hills]

... Best I could do is put a nail through it (which is actually an industry standard test) ...

It'd be just your luck to have the same result that Clive did...

[Brumby]

... Best I could do is put a nail through it (which is actually an industry standard test) ...

It'd be just your luck to have the same result that Clive did...

 

Samsung need to sign up the manufacturer of that battery ... fast!

[ez24]

Not everyone has the resources of UL:  (warning slow on slow connections and 30 second ad )

http://www.nbcnews.com/nightly-news/video/samsung-battery-recall-draws-more-attention-to-smartphone-fires-785548355963?cid=eml_nnn_20161013

In the talk, I believe he said Samsung's batteries do not have protection in them. ?

I do not think Dave is going to blow up his lab.  I guess he could put them inside old test equipment and then say "Don't take it apart - Blow it up" !

[Bud]

What specifically is it about Java bloat that makes any difference?

I guess processor load?
Just stating the fact, the best way to drain the battery for me (iPhone 5) is to go to a news web site, practically any news web site (they all garbage).

EDIT: on EEVBlog Forum site I can stay for long time, it does not have that overheat effect

[stj]

are the "world market" battery's made in japan, or korea?

because the phones sold in china use chinese battery's - and not a single incident with them!

[D3f1ant]

No they having the same problem in china, and have been since the beginning.

http://qz.com/805991/samsung-ssnlf-will-recall-190084-galaxy-note-7-phones-in-china-and-consumers-there-are-angry/

[3roomlab]

Dave? remember the episodes you make with the microphone expert Doug Ford? Is there a local uni prof that is willing to go on YT with you to make a video about batteries voltages limitations charges and then some controlled bangs? Or do it with an Australian Lithium factory expert, or some interesting stuff like Zcell? I think battery storage alone is a huge topic and very interesting, and it helps alot with the electrical side of design when understood well.