The detection of thermal runaway in lithium-ion batteries is vital, particularly in Electric Vehicles and large Energy storage systems. A comprehensive study was conducted by Koch et. al. to evaluate 7 different sensor options, examining their detection speed, signal clarity, and feasibility.
Thermal Runaway Detection Speed:
This is pivotal in ensuring safety, especially in scenarios where batteries are used near humans or animals.
✔️Sensors that reacted fastest to thermal runaway include gas (S2), pressure (S6), and force (S7) sensors.
✔️In contrast, voltage (S1), smoke (S3), and creep distance (S4) sensors exhibited slower detection speeds, which may pose risks to electronics and communication units in thermal runaway events.
Signal clarity:
The ease of evaluating the detection signal, is another key parameter.
✔️Voltage (S1) and gas (S2) sensors displayed a clear step function, while
✔️ smoke (S3) and temperature (S5) sensors exhibited more ambiguous signals.
✔️The signals from creep distance (S4), pressure (S6), and force (S7) sensors required more complex evaluation algorithms due to their brief spikes or minimal signal changes.
Sensor feasibility:
Coverage of factors like size, power consumption, and deployability was also assessed.
✔️Voltage (S1), creep distance (S4), and pressure (S6) sensors scored highly in this category.
✔️However, the gas sensor (S2), despite its excellent signal clarity, scored low due to its large size and significant power consumption.
There isn't a 'one-size-fits-all' sensor for thermal runaway detection. Each sensor brings its own strengths and challenges, and an optimal solution may involve a combination of sensors. Factors such as lifetime stability, diagnosis capabilities, mountability, and cost should be considered in the final sensor selection.
Furthermore, different types of batteries may necessitate different sensor solutions. For instance, the sensor requirements for stationary battery systems used in electricity networks or stand-alone power systems may differ, making other sensor types more suitable for such applications.
Effective detection of thermal runaway in lithium-ion batteries involves careful selection and deployment of appropriate sensors, considering the distinct needs of various battery types and applications.