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The trend toward impenetrable design in small consumer electronics

As a society, we rely on our electronics more than ever before. Depending on their function, small electronic devices can improve communication, enhance quality of life, contribute to physical well-being, and generally provide entertainment, safety, and security. They also produce a lot of waste—waste that is destined for landfills and will never be recycled. The Consumer Electronics Association reports that the average American household uses around 28 personal electronic devices, the vast majority of which will only last about five to seven years before being discarded because they break or because their technology or design becomes outdated.

The United Nations University 2014 Global E-Waste Monitor estimated that, that year, around 41.8 million tons of e-waste was produced globally. Of that total number, the United States contributed 11.7 tons, and only an estimated 15 percent of that 11.7 tons was recycled. Meanwhile, small electronics—including cell phones, wearables, medical devices, hearables, and fitness trackers, just to name a few (all market categories slated for significant future growth)—are increasingly being designed to be impenetrable, and thus unrecyclable.

The government is stepping in to change the way products are designed

This trend toward impenetrable design is unsustainable from the standpoint of both its impact on the environment and its impact on the consumer. Devices designed in this manner are unable to be repaired by anyone outside of the manufacturer—if they can be repaired at all. Their batteries are sealed in and cannot be replaced; and when the battery dies, the entire device dies with it (whether or not it might still function with a new power source). Then, upon device disposal —even when they are disposed of through approved recycling channels —these devices often cannot be disassembled easily enough to be profitable for recycling companies, and end up in the landfill anyway.

In fact, the problems that this design method generates has reached such a level of visibility that now the government is stepping in. Eighteen states have introduced legislation concerning users’ “right to repair” their electronic devices. The most extreme form of legislation has come from Washington State, where a bill is currently being considered that would completely ban the sale of electronic devices that do not have easily removable batteries.

Washington State House Bill 2279 states: “Original manufacturers of digital electronic products sold on or after January 1, 2019, in Washington State are prohibited from designing or manufacturing digital electronic products in such a way as to prevent reasonable diagnostic or repair functions by an independent repair provider. Preventing reasonable diagnostic or repair functions includes permanently affixing a battery in a manner that makes it difficult or impossible to remove.”

This bill still has a way to go before it can potentially become law, and it technically only applies to devices “containing a microprocessor and flat panel computer monitor.” Nevertheless, designers and manufacturers should view it as the canary in the coal mine and a signal that current design methodologies must change or be changed eventually by force of law.

Impenetrable design and the recyclability conundrum

In 2014, and every year before and after, the e-waste that didn’t find second life through disassembly and recycling (around 15%–20% currently) was carted away to landfills or incinerators, where the resources used to make it are lost; Business Insider reports that we throw away approximately $60 million in gold and silver each year in unrecycled cell phones alone. Meanwhile, these discarded devices —which often also contain toxic chemicals, including lead, chromium, mercury, arsenic, and lithium—have the potential to release noxious gases, poison groundwater systems, and leach into soil.

But why do designers choose to build small electronics like this in the first place? There are a number of reasons —the protection of intellectual property being the most highly cited. But another reason, which does not get as much attention, is that the batteries powering these devices are dangerous when mishandled or swallowed.

Sealed-in batteries in small electronics—an unsustainable consumer protection method

In the case of small consumer electronics, the trend toward sealing batteries into devices is often part of an effort to protect consumers from the bad things that can happen to them when a battery is mishandled or swallowed. Poison.org reports that in 2017, 3,240 button cell batteries were ingested in the United States. Of that number, 1,984 of them were ingested by children under the age of six. And while the majority of these incidents were resolved without injury, the injuries that did occur ranged from mild to severe and included esophageal burns requiring surgery, feeding tubes, long hospital stays, and even death in the most tragic cases.

Meanwhile, mishandled batteries and malfunctioning batteries have been known to overheat or even explode, causing damage to both persons and property. We are all familiar with reports of batteries in everything from computers to phones to e-cigarettes malfunctioning in dangerous ways.

Designing for battery failure

Safety is always of paramount importance when a designer develops an electronic device for the general consumer market. Therefore, it is understandable that when designing with the knowledge that a potential battery failure could be catastrophic (and in the worst cases, fatal), sealing in the battery does not seem like such a bad idea. The more difficult it is to access the battery, the more protection from accidental swallowing or mishandling is provided. This makes sense from a consumer protection standpoint. Unfortunately, it is a method that is unsustainable.

Enter silver-zinc: a clean, non-toxic, non-flammable, rechargeable microbattery chemistry that could provide a solution to this ever-growing problem.

Silver-Zinc microbattery technology provides a workaround

It used to be that the only battery technology available that had the energy density and capacity to power small electronics for prolonged periods of time was chemistry that was highly volatile. That meant that when a battery failed, it failed in a spectacular way—a way that was harmful and potentially fatal. But silver-zinc is changing that.

When it comes to the theoretical specific energy density (Wh/kg) and energy density (Wh/l) of rechargeable microbattery chemistry, silver-zinc has the highest of all chemistries currently available, which means it can do an equal or better job at powering the streaming-based electronics that are becoming more and more ubiquitous.

Silver-zinc primary and secondary batteries are non-toxic. They contain a zinc (Zn) anode, a silver oxide (AgO) cathode, and an aqueous-based electrolyte. Since the contents of the battery are non-toxic and more stable, there is less of a chance of the cell expanding and leaking its contents if swallowed. Also, since the voltage of a silver-zinc battery is so much lower than that of a Li-ion battery (1.6V versus 3.7V, respectively) there is less of a driving force for the electrolysis of saliva that could lead to the burning of the esophageal lining. This means that, while swallowing a battery will always present a choking hazard, if a silver-zinc battery were to be swallowed, there is a reduced potential or likelihood for added injury through either hazardous chemicals leaching out or the electrolysis of saliva causing esophageal burns or worse.   

And finally, silver-zinc batteries are non-flammable, which means that the only danger in mishandling the batteries comes from accidently losing them in the shag carpet. Because of this, designers can create products with batteries that can easily be replaced either by third-party repair persons or the consumers themselves, without worrying about the potential for a mishandled battery accident occurring. This frees designers up to create more sustainably designed products that have the potential for a longer usable life and a second life through recycling. Silver-zinc batteries are also 100 percent recyclable, which means that all of their parts can be reused over and over again.

As a primary battery chemistry, silver-zinc is an ideal choice for emerging technologies, including medical devices that are meant to be swallowed or used internally in other capacities. As a secondary battery chemistry, silver-zinc is perfect for long-use electronics that are designed to be worn on the body or in products designed for children and the elderly.

Billions of small electronics coming down the pike represent the potential for a bellwether moment in sustainable design 

Research and Markets predicts that the wireless earbud market in particular and the hearables market in general are slated to experience a 120 percent compound annual growth rate for a value of $7.6 billion by 2020. That is just one corner of the small electronics industry, but it represents an overwhelming amount of potentially non-recyclable trash if we don’t make a change. Silver-zinc can be a part of that change.

One only needs to look to the international hearing aid market to see that change in action. Since 2016, nearly every major hearing aid manufacturer in the world has come out with a hearing aid product powered by silver-zinc rechargeable batteries. These rechargeable hearing aids provide proof of concept, while also providing a road map to new battery chemistry implementation. The convenience of re-chargeability and long-lasting charge are the primary motivators for this market’s adoption of silver-zinc, but the ancillary benefits that come with not needing to seal in the batteries (the devices are easy to maintain and they are easily disassembled at end of life) are probably, in the long run, the greatest benefit to society as a whole.  

Dr. Jeffrey Ortega, Ph.D. is the Director of Research at ZPower

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