With growing interest in solar power storage, backup power, and electric vehicles the race to improve the working of rechargeable lithium batteries is on. In an effort for this, a research team at Berkeley Lab has developed an easy, fast, and inexpensive method to calculate battery performance.
The new method uses thermal waves to measure local concentration of lithium as a function to measure the depth of battery electrodes inside. The study is recently published in the journal Joule.
Using the method, a battery is taken and sensor placed on top of the battery. In this apparatus, signal is sent by the sensor and depending on the signal frequency, the depth of penetration of the wave can be changed. Importantly, the method is much faster and cheaper than other diagnostic procedures. This provides a faster and cheap way to measure battery characteristics.
Termed ‘operando’, the technique works while the reaction is happening. This demonstrates that thermal wave sensing enables to provide spatial information of lithium concentration that is comparable to experimental outcomes obtained using synchrotron X-ray diffraction. The advantage is that the technique does not use a large synchrotron space such as Advanced Light Source.
Meanwhile, to measure battery performance is not an easy task. This makes testing of new materials to improve battery performance expensive and time consuming. The testing of materials to improve charging speed, different areas of electrodes have local degree of charge and age at varying rates. This implies spatially averaged chemical information that existing battery diagnostic tools provide are insufficient to understand degradation of lithium-ion batteries.
The team is now testing the method at lab scale, and next is to test for commercial batteries.