Post-Test Analysis of Battery Materials: Another Part of the Question
As an example, small cells containing 5-V spinel cathodes and graphite anodes were cycled. Upon disassembly, an unexpected “zebra” staining pattern was seen on the separator facing the anode and on the anode itself (see Fig. 1). Further characterization of the separator by energy-dispersive spectroscopy (EDS) showed that lighter-colored areas had significantly more fluorine than did the dark-colored areas, as shown in Fig. 2.
This talk will describe Argonne’s Post-Test Facility, with an emphasis on capabilities and opportunities for collaboration. Cell disassembly, sample harvesting procedures and recent results will be discussed. In particular, SEM and XPS characterization of Li- and Mn-rich NMC and Li-Ni-Mn spinel cathodes, both pristine and aged in graphite-anode cells, reveal changes in chemical composition of evolved surface films.
This work was performed under the auspices of the U.S. Department of Energy, Office of Vehicle Technologies, Hybrid and Electric Systems, under Contract No. DE-AC02-06CH11357.