Electromobility: New early warning system to provide better protection against burning lithium-ion batteries
New system measures and analyzes impedance
Burning lithium batteries in cars can quickly become a danger to people and the environment. Previous warning systems react only a few minutes before a battery spontaneously ignites, the so-called thermal runaway. The Federal Institute for Materials Research and Testing (BAM), together with Vitesco Technologies, a leading international supplier of modern drive technologies and electrification solutions, is developing an early warning system that indicates possible dangerous damage to the battery weeks in advance, thus helping to protect people.
The early warning system measures and analyzes the AC resistance and can thus register dangerous changes in a battery cell much earlier.
BAM
Legal regulations in the European Union stipulate that an electric car must issue a warning signal to people in the passenger compartment at least five minutes before the battery undergoes thermal runaway. This is usually done via the battery management system (BMS), the electronic control unit of the battery. The BMS monitors the performance and condition of individual battery cells and cell assemblies.
Total loss of the battery almost inevitable up to now
Previous warning systems register defective changes in the battery via sensors that react to suspicious changes in temperature or pressure within the battery. The disadvantage of this is that an alarm is only triggered when the battery is already seriously damaged. Thermal runaway and thus probably complete destruction of the battery are usually unavoidable at this point.
In cooperation with Vitesco Technologies, BAM is researching a warning system which indicates critical changes in individual battery cells earlier and thus helps to avoid total loss. The basis of the innovative early warning system is a process that continuously measures and analyzes the electrical alternating current resistance - the impedance - in the cell.
New system measures and analyzes impedance
"A change in impedance can indicate various defects or undesirable conditions," explains Tim Tichter, who is conducting research at BAM as part of the project. "These can be caused, for example, by vibrations, shocks, thermal loads, material failure or even manufacturing defects. Regardless of the particular cause, however, a change in impedance can be expected in any case."
Until now, long measurement times have been necessary for meaningful impedance analyses. They prevent the implementation of such analyses in a BMS. The project team's innovative approach: it modifies the measurement methodology so that a high acceleration in recording and processing impedance data is possible.
The early warning system based on this technology is designed to initiate a service in the event of an emergency or as an immediate protective measure, e.g. shutting down individual cells. This would not only prevent serious damage to lithium batteries and thus save costs, but also better protect people from the dangers of a battery fire.
Note: This article has been translated using a computer system without human intervention. LUMITOS offers these automatic translations to present a wider range of current news. Since this article has been translated with automatic translation, it is possible that it contains errors in vocabulary, syntax or grammar. The original article in German can be found here.
Other news from the department research and development
Get the chemical industry in your inbox
From now on, don't miss a thing: Our newsletter for the chemical industry, analytics, lab technology and process engineering brings you up to date every Tuesday and Thursday. The latest industry news, product highlights and innovations - compact and easy to understand in your inbox. Researched by us so you don't have to.
Most read news
More news from our other portals
See the theme worlds for related content
Topic World Battery Technology
The topic world Battery Technology combines relevant knowledge in a unique way. Here you will find everything about suppliers and their products, webinars, white papers, catalogs and brochures.
Topic World Battery Technology
The topic world Battery Technology combines relevant knowledge in a unique way. Here you will find everything about suppliers and their products, webinars, white papers, catalogs and brochures.
