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Scientists Develop Seawater Battery as an Alternative to Lithium

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Building a battery isn’t terribly complicated: All you need is a cathode, an anode, and an electrolyte that transmits ions between them. In a quest to develop a sustainable alternative to lithium, a team of scientists from South Korea is looking to the sea for some of those components, inhabitat reports.

In their study published in the journal ACS Applied Materials & Interfaces, the nine researchers from Ulsan National Institute of Science and Technology (UNIST) illustrate the science behind their seawater battery. Here the saltwater serves as a catholyte, which acts as both the electron-collecting cathode and the ion-transporting electrolyte simultaneously. Their invention (technically a sodium-air battery) depends on sodium-ion-rich saltwater to function, and with access to the ocean, it’s able to provide a constant charge.

The sustainable nature of seawater makes it the perfect contrast to lithium, which is used in the batteries that power our iPhones and electric cars. Lithium needs to be mined from the earth, which can have damaging effects on entire landscapes. Seawater, on the other hand, is something we have in excess.

The seawater battery still needs some fine-tuning before it’s ready to compete with lithium on the commercial market (UNIST’s battery produces an average of 2.7 volts compared to the average 3.6 to four volts discharged by a lithium-ion battery). But the potential for a day when ocean-powered batteries become mainstream is there.

[h/t inhabitat]

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This High-Tech Material Can Change Shape Like an Octopus
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Octopuses can do some pretty amazing things with their skin, like “see” light, resist the pull of their own sticky suction cups, and blend in seamlessly with their surroundings. That last part now has the U.S. Army interested, as Co.Design reports. The military branch’s research office has funded the development a new type of morphing material that works like an octopus’s dynamic skin.

The skin of an octopus is covered in small, muscular bumps called papillae that allow them to change textures in a fraction of a second. Using this mechanism, octopuses can mimic coral, rocks, and even other animals. The new government-funded research—conducted by scientists at Cornell University—produced a device that works using a similar principle.

“Technologies that use stretchable materials are increasingly important, yet we are unable to control how they stretch with much more sophistication than inflating balloons,” the scientists write in their study, recently published in the journal Science. “Nature, however, demonstrates remarkable control of stretchable surfaces.”

The membrane of the stretchy, silicone material lays flat most of the time, but when it’s inflated with air, it can morph to form almost any 3D shape. So far, the technology has been used to imitate rocks and plants.

You can see the synthetic skin transform from a two-dimensional pad to 3D models of objects in the video below:

It’s easy to see how this feature could be used in military gear. A soldier’s suit made from material like this could theoretically provide custom camouflage for any environment in an instant. Like a lot of military technology, it could also be useful in civilian life down the road. Co.Design writer Jesus Diaz brings up examples like buttons that appear on a car's dashboard only when you need them, or a mixing bowl that rises from the surface of the kitchen counter while you're cooking.

Even if we can mimic the camouflage capabilities of cephalopods, though, other impressive superpowers, like controlling thousands of powerful suction cups or squeezing through spaces the size of a cherry tomato, are still the sole domain of the octopus. For now.

[h/t Co.Design]

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Watch a School of Humpback Whales 'Fish' Using Nets Made of Bubbles 

Just like humans, humpback whales catch many fish at once by using nets—but instead of being woven from fibers, their nets are made of bubbles.

Unique to humpbacks, the behavior known as bubble-net feeding was recently captured in a dramatic drone video that was created by GoPro and spotted by Smithsonian. The footage features a school of whales swimming off Maskelyne Island in British Columbia, Canada, in pursuit of food. The whales dive down, and a large circle of bubbles forms on the water's surface. Then, the marine mammals burst into the air, like circus animals jumping through a ring, and appear to swallow their meal.

The video offers a phenomenal aerial view of the feeding whales, but it only captures part of the underwater ritual. It begins with the group's leader, who locates schools of fish and krill and homes in on them. Then, it spirals to the water's surface while expelling air from its blowhole. This action creates the bubble ring, which works like a net to contain the prey.

Another whale emits a loud "trumpeting feeding call," which may stun and frighten the fish into forming tighter schools. Then, the rest of the whales herd the fish upwards and burst forth from the water, their mouths open wide to receive the fruits of their labor.

Watch the intricate—and beautiful—feeding process below:

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