Tag Archives: Li-Ion

A Bending and Stretching Battery

All electrical and electronic equipment we use in our daily lives requires power to operate. Movable equipment depends on batteries for their mobility. We are used to various types of batteries, like dry cells, lead-acid batteries, rechargeable Ni-Cd and Li-Ion batteries, and so on. However, all the batteries in common use are rigid, non-flexing structures. That may be changing now, as some researchers have claimed to have created a battery that is flexible and stretchable like a snake but unlike a snake, totally safe for humans.

Researchers in Korea claim to have developed a new type of battery that is flexible and stretchable with smooth movements imitating the movements of scales on a snake’s body. However, they have issued assurances that the battery is totally safe for use. This flexible and stretchable battery has a range of applications in contoured devices like wearables and soft robotics.

Although individual scales on the body of a snake are rigid, they can fold together to offer protection against enemies and external forces. The structural characteristics of the scales allow them to move alongside other scales, offering flexibility and stretching capabilities to the snake’s body. At the Korea Institute of Machinery and Materials, researchers from the Ministry of Science and ICT decided to replicate the reptilian characteristics in a mechanical meta structure.

Most conventional wearable devices have the battery in a tight formation with the frame. The new device has several small and rigid batteries in series and parallel connections within a scale-like structure. The researchers ensure the safety of the battery by optimizing its structure so that there is minimum deformation of each battery. They have even optimized the shape of each cell in the battery to offer the highest capacity per unit area.

The connective components and the shape of the battery cell hold the key to this unique device. Each cell is a small hexagonal, resembling the scale on a snake. The researchers have connected each cell with polymer and copper, and there is a hinge mechanism to allow folding and unfolding.

With an aim to mass production in the future, the researchers claim the batteries can be cut and folded with flexible electrodes, with Origami inspiring their manufacturing process.

Wearable devices for humans requiring soft and flexible energy storage can make the best use of these flexible batteries. Another application might be in rehabilitation medical devices for the sick and elderly requiring physical assistance. Soft robots can make use of these flexible batteries as power supply devices at disaster sites when conducting rescue missions. With their ability to freely change shape and move flexibly, these soft robots can move through blocked narrow spaces unhindered by flexible batteries.

Senior researcher, Dr. Bongkyun Jang co-led the research team has commented that mimicking the scales of a snake helped the researchers to develop a flexible battery, making it stretchable and safe to use. The researchers hope that in the future they can develop more soft energy storage devices while boosting their storage capacity. They also hope to develop multi-functional soft robots offering a combination of artificial muscle with actuation technology.