Marcel Weil

Closed-loop recycling of construction and demolition waste in Germany in view of stricter environmental threshold values:

Recycling of construction and demolition waste contributes decisively to the saving of natural mineral resources. In Germany, processed mineral construction and demolition waste from structural engineering is used nearly exclusively in civil engineering (earthwork and road construction sector) as open-loop recycling. Due to the planned stricter limit values for the protection of soil and water, however, this recycling path in civil engineering may no longer be applicable in the future. According to some new guidelines and standards adopted recently, recycled aggregates may also be used for concrete production in the structural engineering sector (closed-loop recycling). Wastes from the structural engineering sector can thus be kept in a closed cycle, and their disposal on a landfill can be avoided. The present report focuses on the determination of maximum waste volumes that may be handled by this new recycling option. Potential adverse effects on the saving of resources and climate protection have been analysed. For this purpose, materials flow analysis and ecobalancing methods have been used.

Life cycle assessment of sodium-ion batteries

Sodium-ion batteries are emerging as potential alternatives to lithium-ion batteries. This study presents a prospective life cycle assessment for the production of a sodium-ion battery with a layered transition metal oxide as a positive electrode material and hard carbon as a negative electrode material on the battery component level. The complete and transparent inventory data are disclosed, which can easily be used as a basis for future environmental assessments. Na-ion batteries are found to be promising under environmental aspects, showing, per kWh of storage capacity, environmental impacts at the lower end of the range published for current Li-ion batteries. Still significant improvement potential is given, especially by reducing the environmental impacts associated with the hard carbon production for the anode and by reducing the nickel content in the cathode active material. For the hard carbons, the use of organic waste can be considered to be promising in this regard. Nevertheless, when looking at the energy storage capacity over lifetime, achieving a high cycle life and good charge–discharge efficiency is fundamental. This represents the main challenge especially when competing with LFP–LTO type Li-Ion batteries, which already show extraordinarily long lifetimes.

A comparative probabilistic economic analysis of selected stationary battery systems for grid applications

This Paper focuses on a comparative probabilistic economic comparison of sodium sulfur batteries (NaS), Lithium-Iron Phosphate batteries (LFP), Vanadium Redox Flow Batteries (VRB), Lead Acid batteries (PbA) and a Pumped Hydro Storage Plant (PHS). Two cases for a load leveling and peak shaving storage application were analyzed and compared. The comparison is based on a comprehensive literature review which showed remarkable deviations within most techno-economic values. This makes it difficult to assess the technologies by a deterministic approach. Therefore, a complementary probabilistic approach was developed in form of a Monte Carlo Simulation (MCS). The results show clearly that among batteries, PbA have the best cost performance followed by NaS and VRB. LFP has the highest costs within all scenarios. However, PHS is the most cost efficient technology for load leveling. In the case of peak shaving the battery costs decrease significantly due to lower initial investment costs.

Recycling of Traction Batteries as a Challenge and Chance for Future Lithium Availability

Lithium-based secondary batteries can be considered the presently most promising electrochemical energy storage systems for mobility applications. There is a strong interest in lithium traction batteries and their prospective mass application in hybrid and fully electric vehicles. The question arising is whether enough lithium is available for the production of such batteries and how much recycling of the batteries will contribute to a higher availability of lithium in the future. Extensive literature search produced different statements regarding presently known reserves and resources, the criticality of lithium, and the degree of recyclability of lithium from traction batteries. An investigated scenario regarding lithium availability and demand suggests that no real lithium scarcity is foreseen in the near future even from the resources policy perspective. After the year 2050, the situation might change when the easily extractable reserves in stable countries will decrease significantly.

Database development and evaluation for techno-economic assessments of electrochemical energy storage systems

A battery storage technology database was developed to assess the state of the art of different battery types by a literature and manufacturer data review. The database contains key techno-economic parameters to provide a solid basis for common assessment, modeling and comparison of battery storage technologies. A new approach is the comparison of literature data with manufacturer data to identify possible inconsistencies between different data sources.

Guidelines to design organic electrolytes for lithium-ion batteries: environmental impact, physicochemical and electrochemical properties

Electrolytes for lithium-ion batteries (LiBs) have been put aside for too long because a few new solvents have been designed to match electrolyte specifications. Conversely, significant attention has been paid to synthesize new electrode materials and especially positive electrodes. Particularly, most of the studies dedicated to the investigation of electrolytes for LiBs have been focused on mixing different molecules. Currently, the development of high-voltage materials for LiBs stimulates the synthesis of new solvents and new salts that are more stable against oxidation. Despite the challenges, only a few teams are active in this field in developing a rational approach combining physicochemistry, electrochemistry and modelling from the molecular to the macromolecular levels. After assembling a critical collection of physicochemical and electrochemical data from the literature, this study highlights the main trends between the chemical structure of the organic dipolar aprotic solvents and their physicochemical and electrochemical properties to provide a guide for chemists to design new electrolytes for LiBs. This guide also includes indicators to take into account the environmental impact of solvent production by including a life cycle assessment of eight different solvents.

Nanotoxicity and Life Cycle Assessment: First attempt towards the determination of characterization factors for carbon nanotubes

Carbon materials, whether at macro, micro or at nanoscale, play an important role in the battery industry, as they can be used as electrodes, electrode enhancers, bipolar separators, or current collectors. When conducting a Life Cycle Assessment (LCA) of novel batteries manufacturing processes, we also need to consider the fate of potentially emitted carbon based nanomaterials. However, the knowledge generated in the last decade regarding the behavior of such materials in the environment and its toxicological effects has yet to be included in the Life Cycle Impact Assessment (LCIA) methodologies. Conventional databases of chemical products (e.g. ECHA, ECOTOX) offer little information regarding engineered nanomaterials (ENM). It is thus necessary to go one step further and compile physicochemical and toxicological data directly from scientific literature. Such studies do not only differ in their results, but also in their methodologies, and several calls have been made towards a more consistent approach that would allow us model the fate of ENM in the environment as well as their potentially harmful effects. Trying to overcome these limitations we have developed a tool based on Microsoft Excel® combining several methods for the estimation of physicochemical properties of carbon nanotubes (CNT). The information generated with this tool is combined with degradation rates and toxicological data consistent with the methods followed by the USEtox methodology. Thus, it is possible to calculate the characterization factors of CNTs and integrate them as a first proxy in future LCA of products including these ENM.

Cost analysis of supercapacitor cell production

A life cycle costing (LCC) is to be performed complementary to the ongoing research on an enhanced supercapacitor pouch cell, in order to provide additional decision support on the best cell chemistry from the economic point of view. Due to the early stage of the project so far merely the production phase is considered. The detailed cost calculation method was chosen and complemented with a scale up using dimension analysis and analogy analysis, in order to be able to utilize this method since available data is either scarce or refers to laboratory scale. It was found that the researched cells are within the lower margin of costs reported in literature. Also the relative contribution of material and production costs as well as energy consumption was in the same range as stated in literature. Although these comparisons should be handled with care as they do not always refer to the exact same item. Further, we concluded that the developed approach provides a sound basis for a reproducible calculation of production costs for technologies at an early research stage.

Proposal of a framework for scale‐up life cycle inventory: A case of nanofibers for lithium iron phosphate cathode applications

Environmental assessments are crucial for the management of the environmental impacts of a product in a rapidly developing world. The design phase creates opportunities for acting on the environmental issues of products using life cycle assessment (LCA). However, the LCA is hampered by a lack of information originating from distinct scales along the product or technology value chain. Many studies have been undertaken to handle similar problems, but these studies are case-specific and do not analyze the development options in the initial design phase. Thus, systematic studies are needed to determine the possible scaling. Knowledge from such screening studies would open the door for developing new methods that can tackle a given scaling problem. The present article proposes a scale-up procedure that aims to generate a new life cycle inventory (LCI) on a theoretical industrial scale, based on information from laboratory experiments. Three techniques are described to obtain the new LCI. Investigation of a laboratory-scale procedure is discussed to find similar industrial processes as a benchmark for describing a theoretical large-scale production process. Furthermore, LCA was performed on a model system of nanofiber electrospinning for Li-ion battery cathode applications. The LCA results support material developers in identifying promising development pathways. For example, the present study pointed out the significant impacts of dimethylformamide on suspension preparation and the power requirements of distinct electrospinning subprocesses. Nanofiber-containing battery cells had greater environmental impacts than did the reference cell, although they had better electrochemical performance, such as better wettability of the electrode, improving the electrodes electrosorption capacity, and longer expected lifetime. Furthermore, material and energy recovery throughout the production chain could decrease the environmental impacts by 40% to 70%, making the nanofiber a promising battery cathode. Integr Environ Assess Manag 2016;12:465-477.

Ecological assessment of nano-enabled supercapacitors for automotive applications

New materials on nano scale have the potential to overcome existing technical barriers and are one of the most promising key technologies to enable the decoupling of economic growth and resource consumption. Developing these innovative materials for industrial applications means facing a complex quality profile, which includes among others technical, economic, and ecological aspects. So far the two latter aspects are not sufficiently included in technology development, especially from a life cycle point of view. Supercapacitors are considered a promising option for electric energy storage in hybrid and full electric cars. In comparison with presently used lithium based electro chemical storage systems supercapacitors possess a high specific power, but a relatively low specific energy. Therefore, the goal of ongoing research is to develop a new generation of supercapacitors with high specific power and high specific energy. To reach this goal particularly nano materials are developed and tested on cell level. In the presented study the ecological implications (regarding known environmental effects) of carbon based nano materials are analysed using Life Cycle Assessment (LCA). Major attention is paid to efficiency gains of nano particle production due to scaling up of such processes from laboratory to industrial production scales. Furthermore, a developed approach will be displayed, how to assess the environmental impact of nano materials on an automotive system level over the whole life cycle.