Battery Safety: Do We Need New Regulations?

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The inside of a Galaxy NoteAt the time of this writing, we are still waiting for an official announcement from Samsung concerning what caused Galaxy Note 7 batteries to catch fire and explode. However, a manufacturing technology company called Instrumental is suggesting new reasons for this dangerous flaw—among them, that there was no space to allow for swelling of the battery. This insight has led me to think about whether safer regulation and standards for cellphone battery designs should (and could) be implemented.

Instrumental decided to tear down a Galaxy Note 7, owing to a suspicion that the flaw was more than a battery part issue. The firm concluded that the smartphone’s aggressive design was responsible for the battery explosions. “What we found was surprising: The design can compress the battery even during normal operation,” said Anna Shedletsky, Instrumental’s CEO and founder, in a blog entry.

“Any battery engineer will tell you that it’s necessary to leave some percentage of ceiling above the battery [10% is a rough rule-of-thumb],” Shedletsky noted. “Over time, the battery will expand into that space. Our two-month-old unit (see photo) had no ceiling: The battery and adhesive was 5.2 mm thick, resting in a 5.2-mm deep pocket. There should have been a 0.5-mm ceiling. This is what mechanical engineers call line-to-line. And since it breaks such a basic rule, it must have been intentional. It is even possible that our unit was under pressure when we opened it.”

If Samsung—in an effort to innovate—pushed boundaries and consciously built a dangerous product, it begs the question: Should standards be changed to better reinforce the safety of consumers from product fails like this? It is confusing to understand which U.S. entities and international organizations take part in lithium-battery safety standards and regulations, and the roles those involved play. Equally unclear is how device manufacturers deal with battery certification. Some of the organizations that are actively addressing these issues include the Nationally Recognized Testing Laboratory (NRTL), the American National Standards Institute (ANSI), Underwriters Laboratories (UL), the Institute of Electrical and Electronics Engineers (IEEE), and the U.S. Consumer Product Safety Commission (CPSC).

UL, for example, provides safety-related certification, validation, testing, inspection, auditing, advising, and training services to a wide range of clients, including manufacturers, retailers, policymakers, regulators, service companies, and consumers. The key standards are UL 1642, UL 1973, and UL 2580.

Given the crossover between them and the different missions of these organizations, it’s hard to tell which group should step in and at what point. Maybe the Jurisdiction of Consumer Product Safety Commission should change the way it protects consumers by putting in steps to eliminate such product fails. Or should we better reinforce lithium-battery safety standards? Should test and certification procedures for designs change, too?

In an effort to innovate and be number one in the market, many companies are rushing their test and validation procedures. As an engineer, I admire and respect how design engineers are always seeking to innovate in order to increase battery operating times while reducing size and weight.

But as a consumer of electronic products, I think safety should go first. No one wants a cellphone to explode while charging on a nightstand next to their bed or inside their purse or pocket. I believe that stronger standards should be implemented to avoid another major fail design and protect consumers. Yet, such steps must be taken without over-limiting innovation.

What do you think should be done? Feel free to share your opinion with me.

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Discuss this Blog Entry 7

on Dec 13, 2016

Interesting analysis. Although I question whether any regulations are needed or if such a basic design issue was "intentional." Another possibility is that recently many companies are moving toward an "agile" system for development programs. Really it's been around for a while, and used to be called "modular design." Basically, this involves breaking up a design and development program into "bite size" pieces and having a team assigned to each one, troubleshoot each one (in isolation!), and then bring them all together for a complete product. It's the "bringing together" phase where things can go wrong.

on Dec 13, 2016

Its ironic that we are rediscovering "modular" design. I guess that is what happens when MBA types tell others that "experience" is no longer advantageous. :-)

on Dec 13, 2016

Good analysis. From it it appears that Samsung didn't do their home work as well as they can. In regards to more regulations, I believe that the ones currently in place cover all safety aspects relating to the chemistry. Indeed, regulations must never be a substitute to good engineering. As suggest by a reader, breaking down the design into modulus certainly helps. We have been using that system with very good results. Please keep writing like analysis to help develop this into a useful forum for innovation.

on Dec 13, 2016

i remember earlier NiCd accumulator days where some 9V block cells suddenly were getting thicker by some 40% in total - in a shape like if a bolt turned around by 90 degree inside their body...

a chemical object under repeated thermal stress does expand and compact any now and then - at every charging cycle, maybe even multiple times per cycle depending on the charger principle. there might be even some contribution of local gas generating and absorbing. the package is often a tight winding of whatever. and if it hits the walls of an outer chamber, that flat or peaky that case might be, it will see in best case lack of space for more expansion and in worst case it will get punched by some sharp metal corner just in its intended (or better hoped?) to be safe original place. the effect will not be much different from hammering a nail into an openly placed battery. you can visit you tube to find references of experimenters doing such things by the dozens. in the end you might see nothing else than what is reported from those assumed to be broken mobile phone design: sudden extrusion of not that healthy gas (consisting of acid, metals, plastics, smoke, spray, vaporized stuff and many alike components) plus maybe some little flame or fire for a few seconds to a few minutes. yes there is energy inside and that one can be released quite quickly in some sort of more or less impressive fireworks.

its chemistry and physics plus some mechanics all three together that makes up a battery in a technology terms of view. if one of the three starts to fail then this can bring the whole set and the unit in question down as well - in some cases this is very noticeable, but luckily in the majority of cases out in the world it is a rather silent process of sudden or long therm functional degradation.

on Dec 13, 2016

I don't think we need more regulation...Samsung is now paying the penalty of recalling hardware and the damage to the brand will be more than and regulation violation fines will every charge. I understand Airlines are asking if passengers have a Samsung phone and having them removed...Probably all models as folks may not remember which model had the flaming battery...I don't plan on getting a Samsung phone soon, I suspect others feel the same...The market in this case will punish the poor design...

on Dec 13, 2016

I find it puzzling that we don't have accepted formfactors for batteries. Back in the 1940's we managed to agree on the standard ANSI/IEC series A/AA/AAA, C,D; why not now? I understand that standardization would limit the creativity, but most applications aren't that critical and would benefit from standardized size and charging protocol negotiation, avoiding debacles like the hoverboard battery fires.
As it is, the dimensions and charging characteristics are all over the place. Even in something as easy to factor as laptop batteries, not only every manufacturer but every laptop model has a different shape and connector, even though until recently most of them internally used 18650 cylindrical cells.
Given all the safety issues, battery should be required to list its static parameters like capacity and safe charging current. I happen to believe that it should also provide those over some sort of 1-wire data bus, together with dynamic parameters such as charge state and temperature---the marginal cost by now is tiny.

on Dec 21, 2016

good article. Obviously Samsung has not developed a solid root cause analysis process. They initially made a big move (don't use product from a particular supplier) based on weak evidence without understanding the root cause. That was very costly for them. Now you show us that maybe they violated basic design practice. Not religiously following strict root cause protocol for field failures is a blatant management error that can sink product lines or entire companies. It's shocking to see such large resource rich companies miss on basic practices. High level management must insure that they have the best available technical advisers and rely on their advice. Ignore them at your peril!

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