EV Disassembly

When considering a traditional ELV dismantling process, disassembly is the second activity, after fluids and hazardous systems decontamination, done by car dismantlers on obsolete vehicles. It represents a high value stage for car dismantlers, given that disassembled components (if in good conditions) can usually be resold as spare parts on the secondary market. For EV disassembly, the main elements taken into account by experts are batteries, electric engines and power electronics (see Table 1).

For the batteries, disassembly is done (after discharging) immediately before either recycling or remanufacturing. Given the lack of information in product variants, battery disassembly is done manually. Only two examples have been found in literature [41,42]. Here, the authors present a concept for a battery disassembly workstation where operators are assisted by robots. While persons perform more complex tasks, robots perform simple and repetitive tasks, such as removing screws and bolts from cases. A similar approach is proposed also by [43], but focusing on EV electric engines.

Finally, other experts focus on power electronics [44,45]. Here, a robotized workstation is proposed for the automatic disassembly of electronic components from EV batteries before their final recycling. An identification of the profitability of recycling such electronic components is also provided.

Table 1. Focus of EV disassembly-oriented papers.

One of the first steps of EoL management is disassembly, typically requiring several time/cost consuming processes. It depends on the costs and risks related to the ability to separate the sub-components from the whole product as to whether disassembly is viable or not. From a technological point of view, manual procedures are usually adopted, explaining the low number of papers focusing on this topic.

EV Recycling

The EVs market is one of the most interesting fields from the recycling point of view. A generic EV embeds lots of key materials (almost 25 kg per car) inside different subsystems and components, offering great recycling potentials. Some important examples are represented by traction batteries, electric drive motors and power electronics [46]. The production of electric cars is expected to grow rapidly, reaching 20 million cars by 2020 [36]. By assuming a mean life of a car of 10 years, there will be an enormous amount of EVs to be recycled by 2030. From these data, it is clear that the strategic importance can be assumed by a preventive decision about alternative sustainable treatments for this waste flow. In particular, the use of industrial symbiosis can minimize material wastage and environmental burdens [23]. A comparison among recycling methods is proposed by some authors [47], in which the final result defines the role of recycling policies that aim to incentivize battery collection and emissions reductions (Table 2).

Table 2. Focus of EV recycling-oriented papers.

Recycling is an opportunity to close the loop of EVs, which aims to reach sustainability goals. However, specific recycling pillars are proposed in the next sub-sections. One of the main results from this review is the significant number of papers focusing on this EoL option. Certainly, reuse is a better solution in terms of the waste hierarchy, but it is not always feasible from a technical point of view. Recycling processes, instead, are suitable to satisfy the circular economy model. Material circularity requires the development of secondary markets where critical and special metals can re-enter in the raw materials cycle. As the authors express, in order to support this development, the economic side must be always taken into account when new technological options are selected.

EV Battery Recycling

The EoL management of EV batteries is one of the most discussed issues in literature. Broadly speaking, EoL strategies can be distinguished in three categories: reuse, remanufacturing and recycling. Literature works are focused on the pros and cons related to each battery technology from both a technical, environmental and economic perspective [83–86]. Other authors focus on both a kind of technology (usually Li-ion) and the management of materials embedded in batteries [87–90] (Tables 3–5). Considering the economic perspective, the cost of EV batteries plays a critical role in determining the commercial viability of EVs, not only during their usage, but also at the end of their useful life. Spent batteries maintain a relevant market value as manufacturers can extract critical materials from key components (e.g., cells and power electronics), typically through hydrometallurgical processes. This topic is investigated from multiple perspectives in literature (see Table 2).

One way to manage obsolete EV batteries is represented by reuse. Given the short lifetime of an EV battery (quantified by many experts as 8–10 years—or the period where the battery capacity reduces to 80% of the original one), their reuse is seen by experts as a reasonable and sustainable strategy, before opting to recycle [48]. Better performances can be obtained by reusing EV batteries together with Renewable Energy (RE) sources in stationary applications. Because of this, several business perspective are proposed in the literature, either under the form of Product-Service Systems (PSSs) [49], dedicated EU regulations [50] or are considered industrial symbiosis [51]. However, the most effective way to manage obsolete EV batteries seems to be a combination of both reuse and recycling practices [52,53].

Table 3. Focus of EV battery reuse-oriented papers.

Several papers have been written about EV battery recycling in the last decades. In general terms, EV battery recycling follows the same process exploited for recovering any type of e-waste, with disassembly, shredding, separation and refining as the main process steps. Depending on the technologies employed during refining (chemical or mechanical ones), it is possible to reach different material recovery performances.

From the current state of the art perspective on EV battery recycling, some works are available in literature, but none of them consider this topic in a broad perspective. Some experts focus on the EV battery design stage by considering the economic and environmental strategies supporting the sustainable treatment of these products [54]. Others follow the same logic, but focus on either a specific type of EV battery [55], national context [18] or recycling method [42].

From the prediction perspective, the focus is on critical materials embedded into EV batteries, either in terms of current availabilities, projected mining capacity or forecasted demands [56]. These assessments are usually presented under the form of decision-support tools [57] or generic simulation platforms [21]. Finally, other experts assess the introduction of EV batteries recycling on current ELV regulations by taking as reference either the Umicore battery recycling process [58] or the Chinese context [50].

From a technological perspective, EV battery recycling is a well-assessed topic in literature, with a prevalent role for the hydrometallurgical process, given its high performances in terms of materials recovery. Some authors describe it through a review on the evolution of chemical recovery technologies [59,60]. Others prefer to focus on either a specific chemical process [61,69], separation processes [66–68], EV battery type [62], leaching agent [63] or recovered material [64,65]. A promising sub-category of hydrometallurgical processes is represented by biological ones. However, only two works have been found in literature on this topic, and both of them focus on organic leaching agents [70,71]. The mechanical process is another way to recover EV batteries. However, in this case, only two works have been found in literature [72,73]. Finally, other experts put together both chemical and mechanical processes, by employing all their benefits [42,74].

Table 4. Focus of EV battery recycling-oriented papers.

Table 5. Technologies supporting EV battery recycling processes.

EV Magnet Recycling

After EV batteries, EV magnets are the second element discussed in literature. Several works present innovative ways to recover Rare Earth Elements (REEs) from obsolete magnets, either coming from mixed sources [75] or specific waste streams (including magnets from HEVs) [76–78]. Other works quantify present and future amounts of recovered REEs from specific HEV components [79]. Finally, different recycling approaches for recycling magnets from HEVs are compared [80].

EV Power Electronics Recycling

As evidenced by the authors many times for common ELVs, in the similar case of EVs, the recovery of electronic components is still in its infancy [46]. Even if electronics in EVs are even more present than in ICEVs, neither industry, nor politics, nor scientists consider its recovery to be an important issue, preferring to focus on batteries (see the previous Sections 3.2 and 3.2.1). The only paper found in literature on this topic compares, both in economic and environmental impact terms, two different ways to recycle EV power electronics, by exploiting either traditional ELV recovery processes or coupling them to a dedicated plant [81].

Fuel Cells Recycling

Another focus related to EVs is the recycling of fuel cells. Given the difficulty of the BEV’s ability to cover long distances, FCEVs will surely take part of the market in future car sales. This way, a percentage of future obsolete EVs will be constituted by FCEVs. Unfortunately, also in this case, only two articles have been found in literature. The first one assesses the effects of a probable update of the current EU ELV Directive towards the recovery of fuel cells [82]. The second one investigates the potential contribution offered by the recycling of FCEVs for meeting the current platinum demand of Europe [13].

EV Remanufacturing

The remanufacturing of components coming from obsolete cars is a well-assessed business. However, from an EV perspective, the literature considers of only EV battery remanufacturing. Considering the few papers focusing on that, EV battery remanufacturing is discussed in terms of either overall process [91], economic performances (compared with reuse/recycling ones) [92,93] or real application cases [94].

EV Environmental Issues

The diffusion of EV technologies is strictly related with energy storage technologies [95]. This way, the environmental analysis has been historically focused on the use phase of EVs. However, many components of EVs (e.g., electronics, magnets and batteries) embed critical raw materials. In this way, experts have started to assess the positive environmental impact associated with EV recycling (as a more sustainable alternative than landfilling), both in terms of GHG emissions reduction [20], electricity mix generation technologies [96], secondary resources recovery (specifically REEs [97], critical metals [12] and lithium [98]) and policy measures that ensure the availability of materials [33].

EV Economic Issues

An important result coming from the present work is that economic issues of EV recycling systems are not well assessed. In particular, the following gaps have been evidenced [99]:

• Scarcity of studies assessing the potential value of different EV battery technologies [100,101];
• Low EV battery recycling rates given the focus of recycling plants on high-volumes [102];
• Translation of expected environmental benefits into real economic benefits [103].

EV Social Issues

Social issues related with EVs are rarely assessed by the experts, mainly in terms of the social influence on eco-innovation adoption. For this topic, just one paper [104] underlined the importance of interpersonal social influence, opinion leadership and personal norms on eco-innovation adoption.

This publication can be found here:https://www.mdpi.com/2071-1050/11/23/6876