All-polymer batteries will be 90% cheaper than lithium-ion

In 2018, Hideaki Horie founded a Tokyo-based company called APB Corp to make all-polymer batteries. He plans to cut mass production costs by 90% and improve their safety.

"The problem with making lithium batteries now is that it's device manufacturing like semiconductors," Horie said in an interview with the Bloomberg. "Our goal is to make it more like steel production."

Making a cell, the fundamental unit of a battery, is a complex process involving cleanroom conditions — with airlocks to regulate heat, continuous air cleaning, and exacting accuracy to avoid highly reactive material contamination. The setup can be so expensive that a handful of top players including South Korea's LG Chem Ltd, China's CATL and Japan's Panasonic Corp spend billions of dollars building an adequate plant.

Horie 's idea is to substitute the fundamental elements of the battery — metal-lined electrodes and liquid electrolytes — with a resin framework. He says this method simplifies and speeds production significantly, making it as simple as "buttering toast."

This makes 10-meter-long battery sheets which can be stacked "like seat cushions" on top of each other to maximize capacity, he said. Importantly, if punctured, the resin-based batteries are often resistant to fire catching.

A puncture will produce a surge in a conventional battery which measures hundreds of amperes, many times the electricity supplied to an average home. Then temperatures can rocket up to 700 degrees centigrade. In employing a so-called bipolar architecture, removing existing voltage bottlenecks and allowing the entire surface of the battery to withstand spikes, APB 's battery prevents these cataclysmic conditions.

"Because of the many incidents, safety has been at the top of mind in the industry," said Mitalee Gupta, senior analyst for energy storage at Wood Mackenzie. "This could be a breakthrough for both storage and electric vehicle applications, provided that the company is able to scale up pretty quickly."

But the technology is not without its shortcomings. Polymers are not as conductive as metal and this may have a major effect on the carrying power of the battery, according to Menahem Anderman, president of Complete Battery Consultancy Inc, California. One downside to bipolar architecture is that in a sequence, cells are bound back-to-back, making it impossible to monitor specific ones, Anderman said. He also asked whether the cost cuts were enough to cope with the incumbents.

"Capital is not killing the cost of a lithium-ion battery," Anderman said. "Lithium-ion with liquid electrolyte will remain the main application for another 15 years or more. It's not perfect and it isn't cheap, but beyond lithium-ion is a better lithium ion."

APB received 8 billion yen ($74 million) in March, which is small by the standards of the broader industry but will be enough to completely outfit one factory for mass production expected to begin next year.

Horie expects the funds will push the plant to 1 gigawatt-hour capacity in central Japan by 2023.