Global warming potential of lithium-ion battery energy storage systems: A review [Umwelteinflüsse von stationären Lithium-Ionen Batteriespeichern: Ein Review]

Gutsch, Moritz; Leker, Jens

Abstract

Decentralised lithium-ion battery energy storage systems (BESS) can address some of the electricity storage challenges of a low-carbon power sector by increasing the share of self-consumption for photovoltaic systems of residential households. Understanding the greenhouse gas emissions (GHG) associated with BESSs through a life cycle assessment (LCA) is important. This review is the first review to look at life cycle assessments of residential BESSs. Our analysis reveals that GHG emissions associated with 1 kWh lifetime electricity stored (kWhd) in the BESS are between 9 and 135 g CO2eq/kWhd. Surprisingly, BESSs using NMC were consistently reported with lower emissions for 1 kWhd than BESSs using LFP. Expanding the system boundary to include the photovoltaic system used for charging the BESS, the photovoltaic system contributed 40–70 % to total GHG emissions. Only two out of 13 LCA studies provided own primary data for the BESS. Therefore, additional sources for primary data were identified. GHG emissions associated with LFP and NMC lithium-ion battery production showed mixed results, depending on the data source. Employing most up-to-date primary data we find LFP with 8 g CO2eq/kWhd and NMC with 12–14 g CO2eq/kWhd, challenging some results of reviewed studies.