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A Cotton Powered Future for EVs?

Big claims emerge from Power Japan Plus about cotton-derived, carbon-fiber battery

2 min read
A Cotton Powered Future for EVs?
Japanese Le Mans team Taisan, here pictured on a pit stop with a petroleum-fueled race car, have partnered with battery company Power Japan Plus to develop a carbon-based battery for an electric-powered racer.
Photo: Power Japan Plus

A Japanese battery maker and a Japanese auto racing team have announced a collaboration to develop an electric car battery, whose promised performance certainly raises an eyebrow. The battery maker’s claims — faster charge times, greater capacity, longer range, greater number of charge-discharge cycles and less volatility than conventional lithium-ion EV batteries — perch the technology at the moment somewhere between “breakthrough” and “too good to be true.”

PowerJapan Plus, whose recent announcement video cites ten years’ lab development of its battery, has to date remained guarded about its proprietary technology. The company’s webpage about the “Ryden Dual Carbon Battery” states that it uses both a carbon anode and carbon cathode made from modified cotton fibers. (Ryden is a homophone of “Raijin,” a Shinto god of lightning, thunder, and storms.)

Not yet revealed is the detailed chemistry of the cathode, anode and electrolyte and how they might work together — and how this unique design might also yield such a powerful battery for EVs. (Though technical specs are still scarce, one fact that may have gotten lost in translation in English-language press coverage to date is the word “organic.” Some reporters have seized on the Ryden’s “organic cotton” composition, implying the cotton fibers in the anode and cathode were grown in a pesticide-free or pesticide-reduced field. We suspect the word “organic” in the present context instead means carbon-based, as in “organic chemistry.”)

Last month, PowerJapan Plus unveiled its Ryden battery to some media fanfare—albeit quizzical fanfare—for the many unanswered questions that remain about the technology. Readers are certainly prudent to remain cautious about Power Japan Plus until more details are known, and third-party verification of their claims are offered up. We’ve been down this road before, such as in 2007 and 2008 when ultracapacitor maker EEStor first made waves about an allegedly revolutionary energy storage technology that never quite materialized.

This month, the Japanese Le Mans auto racing team, Team Taisan, has announced its partnership with PowerJapan Plus to develop Ryden batteries for an electric vehicle it hopes to race with one day. The first stop on that road, they say, is a Ryden-powered electric go-kart that is now slated to start test driving in August. In the PJP-Taisan announcement video, Taisan team owner Yatsune Chiba says it had previously tried to race Tesla electric cars but had difficulties with its batteries overheating.

“We have faced a number of issues with electric vehicle batteries up until now,” says Chiba in the accompanying press announcement. “The Ryden battery from Power Japan Plus is the solution we have been searching for. We will first develop a battery capable of withstanding the rigorous demands of racing, before advancing the technology for use in commercial applications.”

And we will be watching, like fans at the start of a big race, curious to see more and not quite certain yet whom to root for.

The Conversation (0)
This photograph shows a car with the words “We Drive Solar” on the door, connected to a charging station. A windmill can be seen in the background.

The Dutch city of Utrecht is embracing vehicle-to-grid technology, an example of which is shown here—an EV connected to a bidirectional charger. The historic Rijn en Zon windmill provides a fitting background for this scene.

We Drive Solar

Hundreds of charging stations for electric vehicles dot Utrecht’s urban landscape in the Netherlands like little electric mushrooms. Unlike those you may have grown accustomed to seeing, many of these stations don’t just charge electric cars—they can also send power from vehicle batteries to the local utility grid for use by homes and businesses.

Debates over the feasibility and value of such vehicle-to-grid technology go back decades. Those arguments are not yet settled. But big automakers like Volkswagen, Nissan, and Hyundai have moved to produce the kinds of cars that can use such bidirectional chargers—alongside similar vehicle-to-home technology, whereby your car can power your house, say, during a blackout, as promoted by Ford with its new F-150 Lightning. Given the rapid uptake of electric vehicles, many people are thinking hard about how to make the best use of all that rolling battery power.

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