Argonne National Laboratory

Electrochemical Analysis and Diagnostics

Argonne scientist Nancy Dietz Rago analyzes results in the Post-Test Facility. After a battery sample is characterized in the large glove box, it is transferred without exposure to air to the scanning electron microscope for detailed, microstructural characterization.

Argonne scientist Nancy Dietz Rago analyzes results in the Post-Test Facility. After a battery sample is characterized in the large glove box, it is transferred without exposure to air to the scanning electron microscope for detailed, microstructural characterization.

The EADL consists of two parts: battery testing and post-test analysis. Our objectives are to provide reliable, independent, and unbiased evaluations of battery performance and life; and to identify the physical and chemical changes in aged batteries which cause performance degradation. In the past, the cause of performance degradation could only be inferred.

Battery Testing: Argonne has a long history of conducting independent battery performance and life studies for the U.S. Department of Energy (DOE), dating back to the early 1970s. The EADL can test everything from small cells for consumer electronics to full-size electrical vehicle batteries. The EADL can test cells and batteries to any profile using custom design hardware and software. Also, it possesses the ability to test over a wide range of temperatures by using environmental chambers to house the test items, from cells to full-size batteries. We routinely evaluate contract and benchmarking deliverables for the USABC and DOE.

The methods we use accelerate the performance degradation process, enabling the collection of data in a relatively short amount of time. These data are then used for modeling and life estimation.

Post-test Analysis: Battery testing provides a lot of information about how battery performance changes under a given set of conditions. Post-test diagnostics of the aged batteries can provide additional information, which, previously, could only be inferred. Here, the results from physical, spectroscopic, metallographic, and electrochemical tests are used to aid in the further development of a given technology. These techniques are used in a systematic fashion, similar to battery testing. This will make comparisons of failure modes within a given technology and, perhaps, across technologies easier.