Recyclable Energy Storage Device Designed for Sustainability

Smartphones, smartwatches and small drones may soon have access to a different kind of rechargeable power source—one designed not only to store energy, but also to be taken apart and rebuilt. Researchers have developed a lightweight zinc-ion structural supercapacitor that can be disassembled in water-based acidic solution, allowing key components to be recovered and reused. In a demonstration, four of the prototype devices powered a model glider’s propeller, while one individual supercapacitor was dismantled and its carbon-fiber electrode was incorporated into two new devices. The recycled electrode retained comparable electrical performance, suggesting a possible route toward energy-storage systems that generate less electronic waste.

The device, described in ACS Energy Letters, combines several design strategies intended to address the environmental and safety problems associated with conventional rechargeable batteries. Lithium-ion systems dominate portable electronics, but many contain flammable organic electrolytes and are difficult to recycle because their layers are tightly bonded. Separating metals, electrodes, electrolytes and packaging often requires energy-intensive processes, and damaged or discarded devices can release hazardous materials. The new supercapacitor instead uses zinc ions moving through a water-based electrolyte, dissolvable bonding chemistry and conductive components that can be recovered at the end of the device’s service life.

Supercapacitors store energy differently from most batteries. Rather than relying primarily on chemical reactions that transform the active materials during charging and discharging, they store charge at the interface between an electrode and an electrolyte. This allows them to charge and release energy rapidly and withstand many more cycles than typical batteries, although they generally store less energy per unit of mass. The researchers sought to overcome that limitation by combining a high-energy zinc-ion chemistry with a structural design in which the energy-storage device can also contribute to the strength and form of the object in which it is installed.

The prototype contains a zinc metal and copper-foil anode paired with a cathode made from activated carbon fibers. Activated carbon has a highly porous structure, providing a large surface area where charge can accumulate. The zinc electrode supplies zinc ions during operation, while the carbon-fiber electrode supports the complementary charge-storage process. Between the two electrodes, the team placed a solid electrolyte based on a porous resin coated onto a plastic film. The film was soaked in a solution of zinc(II) chloride, supplying the mobile ions needed for the device to function while helping contain the electrolyte in a thin, solid form.

A key feature of the system is the resin’s reversible bonding behavior. When heated, the resin formed strong connections that held the supercapacitor’s layers together and allowed the researchers to fabricate a thin, integrated device. When placed in a mildly acidic, water-based solution, however, those bonds broke apart. The layers separated within about 30 minutes, making it possible to retrieve the carbon-fiber cathode and other components without using the harsh conditions often associated with conventional recycling. Fresh electrolyte and zinc anodes could then be paired with the recovered cathode to construct another energy-storage cell.

The researchers tested the concept in a small glider, integrating four supercapacitors into its wings. The devices were connected to a motor that drove the model’s propeller after the aircraft was launched like a paper airplane. According to the team, the powered glider traveled about 12 feet, or 3.7 meters, compared with approximately 8 feet, or 3.4 meters, when it flew without an external energy source. Although the demonstration was modest in scale, it showed how a structural supercapacitor could be embedded into a lightweight object while performing a useful electrical function rather than simply adding weight as a separate battery pack would.

The most striking test came after the first supercapacitor had completed its initial use. Researchers immersed the device in the mildly acidic solution and recovered its carbon-fiber cathode. That electrode was reused twice, each time with a newly prepared solid electrolyte and a fresh zinc anode. Across its original fabrication and the two subsequent recycling cycles, the carbon-fiber material completed more than 172,000 charge-discharge cycles. Its electrical performance remained similar throughout the testing period, indicating that the electrode’s porous carbon framework survived repeated operation and chemical recovery.

The result is important because recycling is often treated as a process that begins only after a product has been discarded. In this design, recyclability is built into the architecture of the device from the beginning. The choice of water-based electrolyte reduces flammability concerns, while the separable resin and reusable conductive material could make repair and component replacement more practical. Instead of destroying an entire cell to recover a fraction of its materials, manufacturers could potentially disassemble the device, replace degraded parts and return functioning electrodes to service. Such an approach could be particularly useful for lightweight electronics, wearable systems, drones and other applications in which low mass and rapid energy delivery are valuable.

The researchers emphasize that the prototype is not a direct replacement for every lithium-ion battery. Supercapacitors and batteries have different strengths, and real-world adoption will depend on energy density, manufacturing cost, mechanical durability, environmental performance and the ability to scale the recycling process. Even so, the work demonstrates that sustainability and electrical performance do not necessarily have to be opposing goals. By combining zinc-ion chemistry, structural energy storage and reversible materials design, the team has created a device that can power a flying model and then be converted into new energy-storage cells. The study points toward a future in which portable power systems are designed for multiple lives rather than a single trip from factory to landfill.

News Publication Date: 11-Aug-2026

Web References: https://doi.org/10.1021/acsenergylett.6c01274

References: ACS Energy Letters, DOI: 10.1021/acsenergylett.6c01274

Keywords

Zinc-ion supercapacitors, recyclable energy storage, structural supercapacitors, sustainable electronics, electronic waste, porous vitrimer, carbon-fiber electrodes, zinc chemistry, energy storage, supercapacitor recycling