Wildcat Discovery Technologies, a creator of high-throughput methods to rapidly design new battery materials, has developed a new Linear Displacement Measurement (LDM) Device that measures small thickness changes in pouch cells during cycling.
Developed in partnership with BMW, Wildcat’s LDM capability allows new cell performance feedback as parts of projects with its collaboration partners. Measurements of electrode thickness changes can help diagnose failure mechanisms, which can then be used to create improved electrode formulations that mitigate expansion and contraction. Examples of relevant project topics include silicon anode development, lithium metal evaluation and swelling vs. cycle life correlative studies. The device design accommodates a range of pouch cell sizes and thicknesses made by Wildcat or its customers. Wildcat says the device is sensitive enough to get useful data with both single and multi-layer cells.
Chief Scientist Dr. Dee Strand said, “With the Wildcat LDM device, the cell pressure is selected based on chemistry and then held constant during cycling. The device accuracy is +/- 1 micron with 0.1-micron resolution, which is sensitive enough to detect changes for all cell chemistries—even in single-layer pouch cells.”
The company says its instrument has no observable hysteresis or drift during the measurement, and can be operated over a wide range of temperatures. Wildcat has used its new invention to measure dimensional changes during first cycle charge/discharge and cycling at multiple C-rates for cells containing LCO//graphite, NMC//graphite, NMC//silicon and LCO//lithium.
Source: Wildcat Discovery Technologies