The sustainability goals of the current Integrated National Energy and Climate Plan (PNIEC) call for an increasing share of renewable sources in the electricity generation mix. In particular, there will be significant growth, both in percentage contribution and absolute production, from non-programmable renewable sources such as wind and solar. As a result of this growth, both the transmission and distribution networks will require greater flexibility, which can be achieved through modernization efforts aligned with the smart grid approach and through the development of significant storage capacities. In fact, the development of storage systems is one of the PNIEC’s objectives, not only to improve the security of transmission and distribution networks but also to better integrate renewable sources into the electrical system, minimizing overproduction as much as possible.

Electrochemical storage systems are therefore one of the enabling solutions for a sustainable transition of the Italian electrical system. It is essential to evaluate their overall sustainability, both environmentally and economically. In this perspective, a life cycle approach is the most appropriate to assess environmental and economic impacts, using Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) tools. To this end, in 2019, a literature review was conducted on LCA and LCC studies of stationary batteries with the aim of structuring methodologies to apply in life cycle studies that assess the environmental and economic impacts of stationary storage systems.

Building on these methodologies, an LCA study of lithium-ion batteries was conducted during this annual cycle, modeling three types of batteries produced by an Italian manufacturer of stationary storage systems (LFP, NMC 532, and NMC 622) and comparing them with three batteries from the literature (an NMC 111 from Ellingsen et al., an NMC 221, and an LFP from Majeau-Bettez et al.), which were also modeled in LCA terms, updating the cited studies. Regarding battery manufacturing, the most significant phases from an environmental perspective are the production of the cathode and, to a lesser extent, the anode. For most of the impact categories considered, the LFP battery has lower impacts compared to the NMC.

The LCA study revealed that, for all three types of batteries from the Italian manufacturer, the energy required to produce the cells represents one of the main contributions to the Climate Change indicator. Therefore, it is crucial to improve the efficiency of the cell production/assembly process in terms of energy consumption. Additionally, an energy mix with a significant contribution from renewable sources can further reduce the impact on the Climate Change category.

Another key finding is that differences in cell design can lead to significant variations in environmental impacts. In particular, the binder used greatly influences the final results. This applies not only to cell components but also to all other battery components: the inventory phase and data selection are important factors that can significantly influence the final results. Having access to primary data for the cell production phase, provided by an Italian manufacturer, allowed for more accurate results.

The analysis of battery end-of-life also showed that material recovery through pyrometallurgical or hydrometallurgical processes brings NMC cell performance much closer to that of LFP, to the point that in this case, the best chemistry per kWh of capacity is NMC 532.

In 2020, the methodology for calculating the C-LCC indicator was updated to quantify the use of natural resources by products and processes throughout their life cycle. The indicator is based on market prices, a measure of resource scarcity.

NMC batteries are characterized by the highest C-LCC values, while LFP batteries show lower values. However, the gap narrows significantly when considering the possibility of recovering some materials (particularly cobalt) at the end of life. The stability of the results was verified through a Monte Carlo analysis.

A comparison was also made with the resource use economic indicators developed by ReCiPe, which quantify the negative externality caused by the fact that future resource extraction becomes more difficult due to current extraction. Finally, a version of the C-LCC indicator based solely on critical materials identified by the European Commission was calculated, highlighting the challenges posed by NMC batteries in these aspects.