Twente helps advance battery technology

Batteries are part of a green future: they make transport in electric cars and buses possible and play a role in the storage of sustainable energy. Various companies in Twente are working on the application of battery systems. Demcon is developing new technology for producing high-quality batteries, for example, and Super B supplies battery systems for a wide range of electric vehicles.

The University of Twente is also researching battery technology, and all activities are brought together at the Twente Centre for Advanced Battery Technology. Battery Technology is continuously improving, and the demands placed on batteries continue to grow. A battery must recharge quickly for applications in electric transport, but it must also have a high density so that it can bridge long distances. In reality, it is often a trade-off between fast charging and energy density. Professor Huijben’s discovery changes this.

The charging speed of lithium-ion batteries can be increased by up to ten times by using a completely new material, nickel niobate, for the anodes. Huijben: “Charging will be extremely fast with this material while the energy capacity remains high. Higher than with the materials that are currently used for fast charging.” The material also has advantages besides a high charging speed; it is easy to use in today’s industry. “Everyone knows them: cylindrical batteries. The car industry still uses them. But a phone battery has a different shape. The material we have developed is no hindrance to this; it can be used in different shapes.”

The material is applied in situations where charging speed matters. But the discharge speed is important as well. Supplying a lot of power and charging back up quickly. Huijben says that trucks and buses benefit mostly from this discovery. “No material can be charged extremely fast and also have a high energy capacity. You have to make choices. When it comes to electric cars, you do not want to compromise on the maximum distance that you can drive. Charging for half an hour is fine in most cases, it does not have to be a couple of minutes. I think that we will therefore see our fast-charging batteries in trucks and buses mainly, where speed is even more important. And where a larger and heavier battery is not an issue.

The applications are still being researched at the moment. “We still have questions that need answering. What happens, for example, if we replace lithium with another element? Lithium is currently always used in batteries, but there is not a lot of it on earth. So, what happens if we replace it with more sustainable materials such as sodium, which we can extract from seawater?”

The professor is also in contact with the industry. “What is the next step so we can start testing our material on a large scale? Which partners can we start working with? The industry already has a lot of attention for fast-charging materials. Even if you only look at the companies that are working on batteries here in Twente, you can see that they are exploring all directions. This means that we will surely see more applications for batteries in the future. Large companies like Toyota are also working hard to take batteries to the next level. They have a large research facility, and they are working on the ‘solid-state battery’, which is a lot safer than liquid batteries. They will probably bring this product to the market in the next few years.”

Several Dutch companies will be using his invention in the future, according to Huijben. “Partnerships between knowledge institutions, the industry and the ministries have been set up in the Netherlands, to increase our knowledge about batteries. These partnerships include important players such as VDL (which focuses on buses), DAF (which focuses on trucks) and Damen (which deals with transport on water). Together, we will investigate the possibilities. I am confident that manufacturers will start working with the new material in the future.”

And more things related to batteries are happening in Twente. A Battery Safety Lab will be set up at the end of this year for example; a collaboration between the Twente Safety Campus and a Norwegian company called Det Norske Veritas (DNV). The lab will carry out fire safety tests on batteries and battery storage systems. Huijben focuses on things at a cellular level, while BSL looks at entire battery packs: from small batteries in electric bikes to the 100 kilowatt-hour batteries in a Tesla.

Tanja Guyken is project manager of the BSL. “This is a unique project. It will be the first test centre in Europe. Battery tests are still done in the backyard. There is little regulation on this at the moment, but we expect that the government will take extra steps in the coming years. Safety first: if a manufacturer sells batteries for electric cars, he must be able to demonstrate what will happen if a battery catches fire.”

Companies will be able to get answers to their fire safety-related questions in the BSL. “Will the fire be limited to one module? Is the fire safety of a battery compromised when you drop it? You hope not, of course, but we have a gas scrubber that filters harmful substances from the smoke if it is. In other words, we keep it safe for people in the area.”

The fire brigade is also involved in the BSL. Guyken: “We, the fire brigade, also gain knowledge about the behaviour of fire in battery packs in this way. We will be able to advise our fire brigade colleagues about adequate fire fighting techniques and thus make our contribution within the energy transition.”

Guyken expects that the necessary permits for the building will be ready within six months. “We can start building immediately after. I expect that the BSL will be in use by the end of the year.”