Real-time battery analysis for more safety and longer service life

Until now, monitoring the condition of batteries has been limited: Many measurement methods provide inaccurate results or only work when the battery is at rest. This makes precise battery management difficult and can affect both battery life and safety.

A new measurement method offers a solution. Researchers at Fraunhofer IFAM have developed a method that, for the first time, allows the condition of batteries to be analyzed in real time during operation.

How can batteries be analyzed during operation?

The solution is based on an advanced form of impedance spectroscopy. In this process, a special multi-frequency test signal is superimposed onto the charging or discharging current. The battery’s response to this signal provides detailed information about internal physical and chemical processes.

What makes this unique: The data is measured, processed, and evaluated while the battery is in use. Newly developed algorithms reduce the data volume so efficiently that real-time analysis becomes possible. This creates a continuous and precise picture of the battery’s condition during operation.

What advantages does real-time measurement offer for battery use?

Continuous analysis offers decisive advantages for the use of modern battery systems:

• Early detection of overheating: Changes in impedance indicate critical temperature trends within the cell.
• Greater safety: Battery management systems can react more quickly and intervene if necessary.
• Longer service life: Loads can be better controlled and optimized.
• More precise condition assessment: State of charge and aging can be determined much more accurately than with previous methods.
• Optimized charging behavior: Fast-charging processes can be designed to be more efficient and gentler on the battery.

Compared to conventional methods, which often require minutes for an analysis or only work in a stationary state, the new method delivers immediately usable results.

Why is impedance spectroscopy so important for battery analysis?

Impedance spectroscopy is considered a particularly informative method for evaluating batteries. It allows conclusions to be drawn about key parameters such as state of charge, state of health, and safety-related factors.

Until now, however, its application was complex and hardly feasible in operation. The advancement to dynamic real-time analysis overcomes these limitations and, for the first time, makes the method suitable for continuous applications.

Where can impedance spectroscopy be used?

The new measurement method is versatile and not limited to a single battery type. Possible applications include:

• Electric mobility: more precise battery management in electric vehicles
• Renewable energy: more stable and efficient energy storage for wind and solar power plants
• Aerospace: use in safety-critical systems
• Future battery technologies: also suitable for solid-state, sodium-ion, or lithium-sulfur batteries

Real-time monitoring significantly facilitates the use of battery systems in demanding and safety-critical areas.