Photo/IllutrationAll-resin batteries can be turned into various shapes. (Provided by Sanyo Chemical Industries Ltd.)

  • Photo/Illustraion
  • Photo/Illustraion

KYOTO--A chemical maker here is developing a battery made almost exclusively from resin that is safer than conventional storage cells and can be bent into various shapes.

Sanyo Chemical Industries Ltd. plans to mass-produce the resin battery by 2021. Its production costs are expected to be lower than those for conventional batteries.

Demand is growing for batteries for use in electric vehicles, smartphones and other high-tech products. Manufacturers in Japan, China and South Korea are developing the next-generation battery to replace the widely used lithium-ion ones.

Lithium-ion batteries can catch fire or explode if they short circuit due to deformations or being dropped.

The problem can be attributed to their low electrical resistance levels. Lithium-ion batteries contain metal, which is less resistant to electricity and allows electricity to run quickly within.

A battery made of highly resistant resin is believed to have a smaller risk of generating heat and causing fires.

Even at high resistance levels, the new storage cell can maintain its power output by changing the direction of the electric current.

Hideaki Horie, a specially appointed professor of battery studies at Keio University who proposed the idea of resin-based storage cells, described his invention as “the first-ever battery that does not use metal for electrodes or other parts.”

Horie has been involved in the development of the battery system for electric cars at Nissan Motor Co., and started research on the all-resin battery in the 1990s.

One key challenge in commercializing the technology is how to produce dedicated resin for storage cells.

Sanyo Chemical Industries joined the research project in 2012 after one of its employees heard Horie’s lecture. The chemical maker creates mainly water-absorbing resin for disposable diapers and had no know-how on battery development.

Despite the disadvantage, Sanyo Chemical Industries suggested “5,000 kinds of material” to pave the way for the commercial application of Horie’s brainchild.

A characteristic of the resin battery is its simple structure. Larger batteries can be created just by layering positive and negative electrodes made of different resin materials as well as resin-based current collectors.

Resin storage cells do not require the drying process essential to their predecessors, so the sheet-type battery can be “printed” with rotary presses.

This will help slash manufacturing costs by half compared with existing cells, according to Horie.

In addition, resin is flexible, so batteries made of the substance can be shaped freely for various purposes by bending or cutting.

Sanyo Chemical Industries expects the new battery to be used not only in robots and drones but also in large power stations. It has already received inquiries about the product, officials said.

Global sales of the next-generation battery are estimated to rise from 2.1 billion yen ($19.71 million) in 2017 to 2.8026 trillion yen in 2035, according to research firm Fuji Keizai Co.

Horie said his initial sales target is at least 100 billion yen.

“We will move quickly with global expansion in mind,” he said.