In a business park south of the historic university town of Cambridge, researchers at Echion Technologies are searching for the ideal formula for fast-charging vehicle batteries.
Given that many governments have the ultimate goal of net-zero carbon emissions, such an invention would be very timely.
Electric cars already have long-distance capabilities — a range of 200 miles is not uncommon — but many need to be plugged in for hours to reach a full charge.
Being able to do this in less than an hour would make cross-country travel more viable and thus make an electric vehicle a more enticing prospect for consumers.
Faster charging can also improve the productivity of electric buses or vans, as more time is on the road and less time connected to the grid.
Fast-charging batteries can also facilitate the use of electric trains without the need to install expensive electrification infrastructure such as catenary equipment.
At the heart of work at Echion Technologies’ headquarters in south-east England is a chemical element many people have never heard of: niobium.
Despite its low profile, niobium has been on the radar as a potential material for lithium-ion battery anodes — the material in a lithium-ion battery that hosts lithium ions — since the 1980s.
Numerous companies around the world are studying its use, so this metal, sometimes found in stainless steel, could play an important role in the transition to electric transport.
“The work done previously was a starting point. It has not been optimized as a commercial material,” said Benjamin Ting, Chief Commercial Officer of Echion Technologies
“Echion’s focus was to find the optimal material for use as a battery anode suitable for use in mass markets.”
Like much research and development, this effort is extremely painstaking: over the past several years, Echion Technologies has screened nearly 1,000 niobium-based candidate materials for anodes and selected “a very narrow fraction.”
Research and development staff, who together make up about two-thirds of the company’s 30+ employees, produce powders containing mixtures of chemical substances in varying proportions that are synthesized in a furnace.
The powder is then mixed into inks and tested for how well they coat foils to become electrodes.
The resulting electrodes are tested in dozens of small coin-like batteries, each of which looks like batteries found in TV remote controls or bank card readers, for example.
“Our coin-level results have prompted a number of major cell manufacturers to start developing commercial formats using our material,” said Mr. Ting.
combination of key factors
Optimizing battery performance requires juggling multiple variables. The decisive factors include the charge rate, energy density, power density, operating temperature, the number of charge and discharge cycles that a battery can hold, as well as its safety and sustainability.
Optimizing the charging current and energy density is of particular importance, since faster charging batteries often have a lower energy density.
“Often when you try to optimize for one, you will see a compromise in others,” said Mr Ting, an Australian chartered engineer. “We say we offer the best balance.”
Creating something viable in mass production is a “big step” from finding a material that works well in the lab. But the company is quietly confident that it has developed an anode material that could find favor in the market.
“We’re not saying we’re game changers, but we like to think we’re going to make a difference for a number of big industries,” says Mr. Ting. “We’re pragmatic, which gives confidence to those looking to commit to a new battery material as it’s a long-term investment and commitment.”
The company says its XNO material offers long life, safe operation, and the ability to work at a range of temperatures, among other benefits.
It is said to retain 70 percent of its energy output even at temperatures as low as -30 °C and is also resistant to high temperatures, which can be particularly useful in regions such as the Middle East.
Major manufacturers are now producing cells using Echion Technologies’ material, and production is being scaled “into the thousand-ton scale.”
Prof Poul Norby, from the Department of Energy Conversion and Storage at the Technical University of Denmark, says there have already been “many advances” in fast-charging technology, which he says are important “to make vehicles really move electric”.
“If you only look back a few years, the cars might have charged 50 or 100 kilowatts [kW]. Now it has become more common to charge at 150 kW,” he says.
Ultimately, there may be numerous types of niobium-containing anode materials that are gaining commercial acceptance. There is certainly no lack of interest among battery manufacturers.
In fact, just a few miles north of Cambridge is another company, Nyobolt, also working on niobium fast charging technology.
A little further afield, electronics giant Toshiba and two partners announced last year that they were working on developing lithium-ion batteries using niobium-titanium oxide as the anode material, while firms in China, Israel and particularly the US are also focusing on niobium.
Many other companies are developing fast-charging batteries based on various chemical elements.
While Echion Technologies’ niobium-based anode material could find its way into car batteries, the company says it’s more likely to be used in batteries for vans, buses, trains or even mining vehicles.
“A personal EV may not be the best solution, but a delivery truck, a UPS van with multiple drivers and short breaks, these vehicles are on the horizon,” says Mr. Ting.
“Fast charging will be important for buses because having buses sitting around six hours a day is not ideal. They want to be able to use them.”
Prof Norby says improving charging speeds for buses and other large vehicles could allow the use of smaller batteries that could be charged quickly at the end of a bus route, potentially saving money and weight.
This may require the installation of additional charging stations than are needed when charging buses overnight at central depots, so the ideal solution depends on weighing ‘pros and cons’.
Mr Ting says that shrinking battery size is reducing the amount of battery material needed, which reduces the environmental impact of production, and underscores the numerous potential benefits of fast-charging technology.
“We’re very confident that there will be segments citing fast charging as a selling point,” he says.
Updated November 14, 2022 at 2:33 am