Even if the battery is cut, it can restore itself and resume operation once the components are reassembled.
Researchers from Jilin University (China) have developed an elastic and self-healing lithium-ion battery that can stretch up to 250% of its original size without losing its capacity. This is reported by interestingengineering.com.
The research team created the lithium-ion battery using long polymer molecules connected by carbon and nitrogen bonds, known as imine bonds. The polymer can bind to both the positive and negative electrodes of the battery, as well as serve as the electrolyte. The team then built a small lithium-ion battery using lithium iron phosphate and lithium titanate for the electrodes.
By doing so, the team developed a “one-piece” configuration, where the electrolyte and electrodes were fused together at the interface. The battery continued to supply power even when stretched or even cut in half and reassembled.
Researchers worldwide are attempting to create stretchable and self-healing batteries. However, these devices are more flexible than stretchable, and stretchable batteries typically cannot self-heal. But Chinese scientists have achieved record results using dynamic covalent polymers. The polymer electrolyte has an ionic conductivity of 3.6 × 10⁻⁴ S cm⁻¹ at room temperature and the ability to stretch up to 250%. The team also found that the polymer is highly elastic, and its ionic conductivity does not drastically change with increased deformation.
The battery demonstrates self-healing ability at room temperature. After being cut and healed, it showed an average discharge capacity of 126.4 mAh per gram and could steadily power an LED light.
While this may seem like a modest achievement, it lays the foundation for further work in this area and the development of stretchable electronic devices and wearable technologies in the future.
