Mobile storage of electrical energy using high-performance batteries is one of the key technologies for energy supply in the 21st century. High performance and energy density, good cycle stability and durability make lithium-ion batteries strong candidates for use in hybrid and electric vehicles.
However, large-scale lithium-ion cells are extremely susceptible to faults as a result of even the smallest of errors during the production process. Although the exact process parameters are documented during production, a number of faults can only be detected when the battery is actually being used. Monitoring the internal life of the battery during formation and use is currently not possible – or only to a limited extent – but would be a great advantage.
In the Smart-LIB project funded by the Baden-Württemberg Ministry of Economics, lithium-ion cells in the PHEV1 format were equipped with internal sensors (T, V) for the first time and then subjected to a stress test. The collected sensor data was wirelessly transferred to an external receiver via an infrared transmitter, thus monitoring the state-of-health of the cell (SOH) in real time. This opens up new possibilities to detect critical battery conditions at an early stage and avoid failure in the field.