This Energy Storage Device Survived 172,000+ Charge Cycles and Could Be Reused. Here's How

Smartwatches, smartphones, drones and other compact electronic devices all depend on lightweight rechargeable energy systems. But when these devices reach the end of their useful lives, their batteries and other electronic parts often become difficult-to-recycle waste.

Researchers have now developed a new type of recyclable supercapacitor that could offer a more sustainable solution. The compact energy-storage device can be quickly taken apart, allowing important components to be recovered and reused. In laboratory tests, one of these components was successfully used in two new supercapacitors without losing significant performance.

The research, published in ACS Energy Letters, demonstrates that high performance and sustainability can be designed into the same energy-storage technology.

A More Sustainable Alternative

Many rechargeable electronic devices currently rely on lithium-ion batteries. Although lithium-ion technology offers high energy density, these batteries can contain flammable electrolytes and are not always easy to recycle. Their different layers and materials are often difficult to separate, making recovery and reuse more challenging.

To address these problems, researchers Tse Nga Ng, Nandu Koripally and their colleagues explored a different approach.

Their new supercapacitor uses zinc ions and a water-based, nonflammable electrolyte. It also contains adhesives that can be dissolved when needed and electrically conductive materials that can be recovered for future use.

The design builds on earlier research combining zinc-ion chemistry with structural supercapacitors. According to Koripally, the lead author, the team wanted to create an energy-storage device that could not only deliver strong performance but also support repair, recycling and second-life use.

How the New Supercapacitor Works

The researchers constructed the device using several thin layers.

One important component was a zinc metal–copper foil anode, which serves as one of the electrodes. The other electrode, or cathode, was made from activated carbon fibers.

Between these electrodes, the researchers placed a solid electrolyte. This electrolyte consisted of a porous resin coated onto a plastic film and soaked in a solution containing zinc chloride.

The resin played a particularly important role in making the device recyclable. When heated, it formed strong bonds that held the different layers together. However, when placed in a mildly acidic liquid, those bonds could be broken.

After the layers were combined using heat, the result was a thin supercapacitor capable of operating at a voltage of about 2 volts.

This combination of strong construction during use and easy separation at the end of life is one of the most important features of the design.

Putting the Technology to the Test

The researchers wanted to demonstrate that their supercapacitors could provide useful power in a real application. For their proof-of-concept experiment, they integrated four of the devices into the wings of a small model glider.

The glider was launched in a way similar to throwing a paper airplane. When its propeller motor was powered by the supercapacitors, the aircraft traveled about 12 feet (3.7 meters).

Without an external power source, the glider traveled about 8 feet (3.4 meters).

Although this was a small demonstration, it showed that the lightweight energy-storage devices could deliver enough power for a practical miniature electric system.

A Supercapacitor That Can Be Taken Apart

The most notable test came after the original device had been used.

The researchers placed one supercapacitor into a mildly acidic, water-based solution. Within about 30 minutes, its layers separated.

This allowed the team to recover the activated carbon-fiber cathode rather than treating the entire device as waste.

The recovered carbon-fiber material was then used to build another supercapacitor with a fresh solid electrolyte and a new zinc anode. After that device was used, the carbon fibers were recovered again and incorporated into a third supercapacitor.

In other words, a key material from the original device received two additional lives.

Strong Performance After Reuse

Recycling often raises an important question: Does reused material perform as well as new material?

In this case, the results were encouraging.

From the initial fabrication through two additional rounds of recycling, the carbon fibers successfully completed more than 172,000 charge-discharge cycles. Their electrical performance remained similar throughout the process.

This suggests that recycling did not significantly compromise the performance of the carbon-fiber component.

The finding is particularly important because energy-storage technologies need to balance several competing requirements. They must be lightweight, powerful, durable and safe, while also becoming easier to manufacture, repair and recycle.

Reducing Electronic Waste

The researchers believe their approach could help reduce waste from future lightweight electronic systems.

Instead of designing energy-storage devices only for their first period of use, manufacturers could consider what happens to their materials after the device is no longer needed. Components that can be separated and reused could reduce the amount of material sent to waste streams and potentially lower the need for new raw materials.

The concept could be especially useful for compact electronics, wearable devices, drones and other applications where lightweight structural energy storage is important.

However, the technology is still at the research and proof-of-concept stage. Further development will be needed to determine how the design performs under larger-scale manufacturing conditions and across different real-world applications.

Sustainability and Performance Can Work Together

The research highlights a broader change in how energy-storage devices can be designed. Instead of treating recycling as something that happens only after a product is discarded, researchers can build recyclability into the device from the beginning.

Koripally says the work shows that sustainability and performance do not necessarily have to be opposing goals. By considering the complete life cycle of materials, engineers can design energy-storage systems that remain effective while also being easier to repair and reuse.

The new recyclable supercapacitor is therefore more than an alternative energy-storage device. It represents a design philosophy in which performance, durability and end-of-life recovery are considered together.

As the demand for portable electronics and lightweight electric systems continues to grow, such approaches could play an important role in reducing electronic waste. A future in which energy-storage components can be easily separated, recovered and given a second life may help make the rapidly expanding electronics industry more sustainable.

Reference: Nandu Koripally, Lulu Yao, Robert Chambers, Shengqiang Cai, Tse Nga Ng; Recyclable Zinc Ion Structural Supercapacitor Enabled by Porous Vitrimer. ACS Energy Lett. 2026; https://doi.org/10.1021/acsenergylett.6c01274