The Environmental Performance of Traction Batteries for Electric Vehicles from a Life Cycle Perspective

Abstract

The aim of this review article is the analysis of the results obtained from the scientific literature concerning all the phases that make up the life cycle of traction batteries for electric vehicles, in order to evaluate the associated environmental impact. In this regard, some scientific articles dealing with LCA studies concerning electric vehicles, with particular reference to batteries, will be examined. The revision of these articles will provide a general framework for the production, use and recycling phases of traction batteries. In particular, different parameters that influence the outcome of the LCA studies will be shown, parameters on which we can then act to improve the environmental impacts of the transition from internal combustion vehicles to electric mobility. These parameters are represented by the chemistry of the battery considered, aspect at the centre of the discussion, by the specific energy and efficiency of the battery pack, by the durability of the latter, but also by other aspects, such as the energy mix considered (both for the production phase, for the use phase and for recharging) and the functional unit chosen for the study, which determines a different approach, related to the analysis of a specific problem or aspect rather than another. Finally, the usefulness of the recycling practice and the related problems will be shown. In fact, the recycling must be perfected according to the battery chemistry in question to obtain benefits and better reduce environmental loads.

Battery only electric traction for freight trains - A technical and operational assessment

“…This impact might be assessed in a life-cycle model, which takes into account three phases: i) mineral extraction and battery production; ii) battery use and iii) battery recycling. 40 The environmental impact considers the effects of i) GHG emissions; ii) human social impact and toxicity and iii) metal depletion.…”

“…The production of cobalt, a key component in NMC batteries, is also concentrated (around 66% in an African country -The Democratic Republic of Congo), which has drawn international concerns, associated with workers' safety and environmental issues, related to inadequate mining tools and for reportedly using child labor. 41,42 Sandrini G. et al 40 report that, regardless of the battery chemistry, the energy requirements for the production phase are a major cause of global warming, with the materials preparation phase accounting for the main impact.…”

“…Finally, regarding the recycling phase, it is important to highlight that most of the materials used in traction batteries are precious and toxic metals, such as nickel, lithium, cobalt and manganese, as well as organic and plastic materials, that can produce large quantities of pollutants, if not disposed of properly. 40 Nevertheless, the regulatory authorities have not yet set recycling guidelines to the battery manufacturing process, with current battery manufacturers not yet designing them to optimize recycling, especially with the absence of a labeling policy, essential to identify the different chemistries of all battery components. Furthermore, an optimized disassembling process (provided the required safety during its use) is important to avoid the use a pyrometallurgy recycling process, which requires high energy, is expensive and inefficient in recovering the active materials.…”

“…Sandrini G. et al 40 report that, regardless of the battery chemistry, the energy requirements for the production phase are a major cause of global warming, with the materials preparation phase accounting for the main impact.…”

“…In the battery use phase, the grid energy mix strongly influences indirect (GHG and criteria pollutants) emissions, which also varies with time slots for recharging, with the night shift tending to set lower environmental loads than the daytime. 18 - 40…”