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Life cycle assessments (LCA) and environmentally extended input-output (EEIO) analyses both strive to account for direct and indirect environmental impacts of goods and services. Different methods have been developed to hybridize these two techniques and minimize the impact of their respective shortcomings on final assessments. These weaknesses, however, have not been extensively studied in a quantitative manner, especially not for complete LCA and EEIO databases. To this end, we jointly analyzed process-based and input-output-based data sets. We first evaluated their complementarity. Though the LCA data was more detailed overall, some sectors of the economy were more precisely represented in the EEIO database. We then contrasted the representation of the different economic sectors in the LCA database with the economic, environmental, and structural importance of these sectors. The weakness of the correlation results led us to conclude that process-inventory efforts have not been systematically directed at the most important sectors of the economy. The LCA data was also used to evaluate the sensitivity of EEIO data to aggregation uncertainty. This sensitivity proved highly inhomogeneous. We conclude the presence of important research inefficiencies stemming from the lack of hybrid perspective in the compilation of LCA and EEIO data.

This study presents the life cycle assessment (LCA) of three batteries for plug-in hybrid and full performance battery electric vehicles. A transparent life cycle inventory (LCI) was compiled in a component-wise manner for nickel metal hydride (NiMH), nickel cobalt manganese lithium-ion (NCM), and iron phosphate lithium-ion (LFP) batteries. The battery systems were investigated with a functional unit based on energy storage, and environmental impacts were analyzed using midpoint indicators. On a per-storage basis, the NiMH technology was found to have the highest environmental impact, followed by NCM and then LFP, for all categories considered except ozone depletion potential. We found higher life cycle global warming emissions than have been previously reported. Detailed contribution and structural path analyses allowed for the identification of the different processes and value-chains most directly responsible for these emissions. This article contributes a public and detailed inventory, which can be easily be adapted to any powertrain, along with readily usable environmental performance assessments.