A research agenda for life cycle assessment of electromobility

This is a pre-study, financed by the Swedish Energy Agency, with the aim of presenting a research agenda for life cycle assessment (LCA) of electromobility. Electric vehicles are often portrayed as potential remedies for numerous environmental problems, most notably global warming. At the same time, LCA studies already conducted have shown that electric vehicles can also worsen some environmental problems through increased use of abiotic resources and emissions of toxicity substances. Whether electric vehicles truly do reduce global warming impacts also depends on the production technology for the electricity. This type of ambiguous result calls for a systematic assessment of the environmental and resource performance of electromobility, such as by LCA. Considering the many overlapping issues related to LCA and electromobility, it can be thought of as a nexus, involving different technologies (batteries, fuel cells, electronics, electric motors, different vehicles, etc.) and different environmental issues (resource use, criticality thereof, energy-related emissions, etc.). In order to investigate which parts of this nexus are most interesting to study further, information was obtained from three sources: (1) workshops with relevant industry stakeholders, (2) interviews with researchers in the field, and (3) a literature study of key documents in the area of LCA of electromobility. The result is formulated into a research agenda for LCA of electromobility, which consists of ten research questions. Seven of these regard electromobility technologies important to study (e.g. future battery chemistries and electric aviation), whereas three regard methodological issues (e.g. impact assessment of abiotic resources). Two near-term research projects have been formulated, for which funding applications will be submitted during 2019, and together they cover a majority of the research questions

Life cycle assessment of city buses powered by electricity, hydrogenated vegetable oil or diesel

This study explores life cycle environmental impacts of city buses, depending on the: (1) degree of electrification; (2) electricity supply mix, for chargeable options; and (3) choice of diesel or hydrogenated vegetable oil (HVO), a biodiesel, for options with combustion engine. It is a case study, which uses industry data to investigate the impact on climate change, a key driver for electrification, and a wider set of impacts, for average operation in Sweden, the European Union and the United States of America. The results show that non-chargeable hybrid electric vehicles provide clear climate change mitigation potential compared to conventional buses, regardless of the available fuel being diesel or HVO. When fueling with HVO, plug-in hybrid and all-electric buses provide further benefits for grid intensities below 200 g CO₂ eq./kWh. For diesel, the all-electric option is preferable up to 750 g CO₂ eq./kWh. This is the case despite batteries and other electric powertrain parts causing an increase of CO₂ emissions from vehicle production. However, material processing to make common parts, i.e. chassis, frame and body, dominates the production load for all models. Consequently, city buses differ from passenger cars, where the battery packs play a larger role. In regard to other airborne pollutants, the all-electric bus has the best potential to reduce impacts overall, but the results depend on the amount of fossil fuels and combustion processes in the electricity production. For toxic emissions and resource use, the extraction of metals and fossil fuels calls for attention

Quantifying the life-cycle health impacts of a cobalt-containing lithium-ion battery

Purpose: Lithium-ion batteries (LIBs) have been criticized for contributing to negative social impacts along their life cycles, especially child labor and harsh working conditions during cobalt extraction. This study focuses on human health impacts — arguably the most fundamental of all social impacts. The aim is to quantify the potential life-cycle health impacts of an LIB cell of the type nickel-manganese-cobalt (NMC 811) in terms of disability-adjusted life years (DALY), as well as to identify hotspots and ways to reduce the health impacts. Methods: A cradle-to-gate attributional life-cycle assessment study is conducted with the functional unit of one LIB cell and human health as the sole endpoint considered. The studied LIB is produced in a large-scale “gigafactory” in Sweden, the cobalt sulfate for the cathode is produced in China, and the cobalt raw material is sourced from the Democratic Republic of the Congo (DRC). Potential health impacts from both emissions and occupational accidents are quantified in terms of DALY, making this an impact pathway (or type II) study with regard to social impact assessment. Two scenarios for fatality rates in the artisanal cobalt mining in the DRC are considered: a high scenario at 2000 fatalities/year and a low scenario at 65 fatalities/year. Results: Applying the high fatality rate, occupational accidents in the artisanal cobalt mining in the DRC contribute notably to the total life-cycle health impacts of the LIB cell (13%). However, emissions from production of nickel sulfate (used in the cathode) and of copper foil (the anode current collector) contribute even more (30% and 20%, respectively). These contributions are sensitive to the selected time horizon of the life-cycle assessment, with longer or shorter time horizons leading to considerably increased or decreased health impacts, respectively. Conclusions: In order to reduce the health impacts of the studied LIB, it is recommended to (i) investigate the feasibility of replacing the copper foil with another material able to provide anode current collector functionality, (ii) reduce emissions from metal extraction (particularly nickel and copper), (iii) increase the recycled content of metals supplied to the LIB manufacturing, and (iv) improve the occupational standards in artisanal mining in the DRC, in particular by reducing fatal accidents

A model platform for solving lithium-ion battery cell data gaps in life cycle assessment

With the advent of electromobility, life cycle assessment studies need to keep up with growing number of cell formats and chemistries being adopted for various vehicle applications. This often hindered by lack of data. A model platform is presented, starting with a cell design computation model which is used for calculating the mass of cell components and other design parameters. It also includes a cell performance model, which will link to a battery pack and vehicle model, both used for estimate losses caused by the cell during vehicle operation. Furthermore, the platform comprises a model generating inventory data for life cycle assessment of lithium-ion battery cell production. Together, these parts feed information to life cycle assessment calculations covering both production and use of lithium-ion battery cells. The aim is to support technology development and provide an understanding of how various design changes in cells link to environmental impacts. This conference paper explains model parts and provides exemplary results

Life cycle environmental impacts of current and future battery-grade lithium supply from brine and spodumene

Life cycle assessment studies of large-scale lithium-ion battery (LIB) production reveal a shift-of-burden to the upstream phase of cell production. Thus, it is important to understand how environmental impacts differ based on the source and grade of extracted metals. As lithium is highly relevant to several current and next-generation cell chemistries, we reviewed the effect of varying grades in different sources of lithium (brine and spodumene) worldwide. The review covered the Ecoinvent database, scientific literature, and technical reports of several upcoming production facilities. The results showed that lower-grade lithium brines have higher environmental impacts compared to higher-grade brines. However, spodumene-based production did not show such a trend, due to different technical process designs of the facilities reviewed. Water use impacts are higher in lower-grade sources and are expected to increase with decreasing lithium concentration. This could specifically be an issue in brine-based production, where brine is extracted from already water scarce regions and evaporated, thus increasing the risk of freshwater availability. However, these aspects of water use are not addressed in existing life cycle impact assessment methods. In the context of large-scale LIB cell production, the reviewed lithium hydroxide production routes account for 5–15% of the climate change impacts

Implementation of the crustal scarcity indicator into life cycle assessment software

This report provides a detailed description of how the crustal scarcity indicator (CSI) is\ua0implemented into the life cycle assessment (LCA) software OpenLCA. The original\ua0characterization factors for the CSI, called crustal scarcity potentials (CSPs), were designed to be\ua0paired with life cycle inventory data formulated as the amount (mass) of elements extracted from\ua0the crust. However, some inventory data is not formulated in terms of mass of elements extracted.\ua0For example, data in the Ecoinvent database – the world’s largest LCA database – can also be\ua0expressed in terms of the amount of mineral extracted, the amount of rock extracted, or the amount\ua0of ore extracted. In order to implement the CSI into OpenLCA in a way that captures such nonelement\ua0flows, we construct five categories of inventory data for material flows extracted from the\ua0crust. Type A flows are flows of elements, such as lead or tin, which the original CSPs can be paired\ua0with. Type B flows are flows of minerals, such as kieserite or stibnite. Type C flows are flows of\ua0rocks and groups of minerals, such as basalt or olivine. Type D flows are ores, like copper ore. Type\ua0A flows are paired with the CSPs of the respective element types. However, for type B, C and D\ua0flows, new CSPs were calculated based on their respective content of different elements. These new\ua0CSPs can be found in Appendix A-D. In addition, type E flows are those that are too vaguely\ua0formulated in the Ecoinvent database, for example as general metal or ore, making it impossible to\ua0derive CSPs. In the concluding discussion, we show that this implementation gives the CSI a wider\ua0coverage of different inventory flows than other existing mineral resource impact assessment\ua0methods implemented in different packages for OpenLCA. The implementation might thus be\ua0considered a guidance for a more all-encompassing implementation of other mineral resource\ua0impact assessment methods as well

Environmental life cycle implications of upscaling lithium-ion battery production

Purpose Life cycle assessment (LCA) literature evaluating environmental burdens from lithium-ion battery (LIB) production facilitieslacks an understanding of how environmental burdens have changed over time due to a transition to large-scale production. Thepurpose of this study is hence to examine the effect of upscaling LIB production using unique life cycle inventory data representativeof large-scale production. A sub-goal of the study is to examine how changes in background datasets affect environmental impacts.Method We remodel an often-cited study on small-scale battery production by Ellingsen et al. (2014), representative ofoperations in 2010, and couple it to updated Ecoinvent background data. Additionally, we use new inventory data to modelLIB cell production in a large-scale facility representative of the latest technology in LIB production. The cell manufacturedin the small-scale facility is an NMC-1:1:1 (nickel-manganese-cobalt) pouch cell, whereas in the large-scale facility, the cellproduced in an NMC-8:1:1 cylindrical cell. We model production in varying carbon intensity scenarios using recycled andexclusively primary materials as input options. We assess environmental pollution–related impacts using ReCiPe midpointindicators and resource use impacts using the surplus ore method (ReCiPe) and the crustal scarcity indicator.Results and discussion Remodelling of the small-scale factory using updated background data showed a 34% increase ingreenhouse gas emissions — linked to updated cobalt sulfate production data. Upscaling production reduced emissions bynearly 45% in the reference scenario (South Korean energy mix) due to a reduced energy demand in cell production. However,the emissions reduce by a further 55% if the energy is sourced from a low-carbon intensity source (Swedish energymix), shifting almost all burden to upstream supply chain. Regional pollution impacts such as acidification and eutrophicationshow similar trends. Toxic emissions also reduce, but unlike other impacts, they were already occurring during miningand ore processing. Lastly, nickel, cobalt, and lithium use contribute considerably to resource impacts. From a long-termperspective, copper becomes important from a resource scarcity perspective.Conclusions Upscaling LIB production shifts environmental burdens to upstream material extraction and production, irrespectiveof the carbon intensity of the energy source. Thus, a key message for the industry and policy makers is that furtherreductions in the climate impacts from LIB production are possible, only when the upstream LIB supply chain uses renewableenergy source. An additional message to LCA practitioners is to examine the effect of changing background systemswhen evaluating maturing technologies

Does the grade and source of lithium used in batteries matter?

Lithium-based batteries are increasingly being implemented for storing energy, both in transportation and stationary applications. As battery manufacturing matures and becomes more efficient, the environmental burdens of these batteries shift upstream, for example to the lithium supply. The majority of the current global lithium supply comes from two sources – spodumene mined in Australia and brines extracted in Chile. In this study, we review existing life cycle assessment literature on lithium production regarding data completeness and quality, as well as temporal and geographical relevance. Preliminary results indicate that the currently most used datasets in life cycle assessment studies of lithium-based batteries lack quality and representativeness of current operations. To address these gaps, this study compiles several new datasets for lithium production representing different geographies, technical processes, and lithium grades. First, we compare the inventory data of other existing lithium supply datasets, both older and newly compiled, regarding their quality and representativeness. Second, we look at future scenarios for lithium supply based on global proven reserves and analyze the influence of changing grades on future environmental impacts. Third, we examine the potential for reducing environmental impacts from the lithium-supply chain by linking all electricity inputs to renewable sources. Finally, we use the various lithium datasets compiled in this study to update the results of a giga-scale lithium-ion battery manufacturing in a recently published study. We focus on climate change and mineral resource use impacts. Additionally, to inform a growing debate in scientific literature around the water use impacts related to brine and freshwater extraction in water-stressed regions of the world, such as the salars in South America, we use regionalized water use assessment indicators to further assess the burdens of battery production from water use perspective

Metal requirements for road-based electromobility transitions in Sweden

This research investigated the metal requirements for electrifying Swedish cars and heavy-duty trucks and refueling infrastructure. We assessed vehicle and infrastructure metal use given four cornerstone scenarios: battery electric vehicles and chargers, conductive and inductive electric road systems, and fuel-cell vehicles, besides an internal combustion engine scenario. Twenty-seven metals were evaluated. To our knowledge, this study presents a first attempt to develop a detailed inventory of prevailing and prospective charging infrastructures. Our study estimated total metal requirement at 7400–9600 kt and infrastructure share at 6%–25% (200–2400 kt). Infrastructure requires about 15% of gold, 30%–40% of silver and copper, and 40%–60% of molybdenum. Results revealed that the following metal flows contribute the most to long-term resource scarcities: rhodium in fossil-fueled vehicles; gold in electric vehicles; palladium and gold in conductive and copper and palladium in inductive electric road systems; as well as platinum in fuel cells