Time-dependent global sensitivity analysis with active subspaces for a lithium ion battery model

Funding information U.S. Department of Energy Office of Science, Office of Advanced Scientific Computing Research, Applied Mathematics program, DE-SC-0011077, Defense Advanced Research Projects Agency’s Enabling Quantification of Uncertainty in Physical Systems, U.S. Department of Energy Office of Science, Office of Advanced Scientific Computing Research, DE-SC0006402, NSF, CMMI-1454601, Renewable energy researchers use computer simulation to aid the design of lithium ion storage devices. The underlying models contain several physical input parameters that affect model predictions. Effective design and analysis must understand the sensitivity of model predictions to changes in model parameters, but global sensitivity analyses become increasingly challenging as the number of input parameters increases. Active subspaces are part of an emerging set of tools for discovering and exploiting low-dimensional structures in the map from high-dimensional inputs to model outputs.We extend linear and quadratic model-based heuristics for active subspace discovery to time-dependent processes and apply the resulting technique to a lithium ion battery model. The results reveal low-dimensional structure and sensitivity metrics that a designer may exploit to study the relationship between parameters and predictions.