In recent years, sustainability has been integrated as one of the fundamental pillars of the energy storage sector. Proof of this is the Regulation on batteries and battery waste, approved by the European Parliament in July 2023. This legal framework aims to ensure that batteries can circulate freely in the EU internal market, eliminating trade barriers and facilitating fair competition. All this, moreover, with the aim of reducing and preventing the negative impacts derived from the generation and management of battery waste on the environment.

One of the most relevant articles of this regulation from the sustainability point of view is Article 7, which defines for each type of battery, the date by which it will be mandatory to submit the Carbon Footprint declaration, as well as the minimum information required.

Challenges and advances in the Carbon Footprint of batteries

The Carbon Footprint is an important component in the environmental assessment of batteries, as it determines the total amount of CO₂ emissions generated directly or indirectly during the life cycle, including from the extraction of raw materials to production, use and final disposal.

In the context of the Battery Regulation, the document "Rules for the calculation of the Carbon Footprint of Electric Vehicle Batteries", developed by the Joint Research Center (JRC), will be the basis for the application of the requirements established in Article 7 of the Regulation, since, through clear alignments and common framework, it determines the methodology for the calculation and verification of the Carbon Footprint of batteries for electric vehicles.

This document is based on the Environmental Footprint (EF) method developed by the European Commission, as well as on the Product Environmental Footprint Category Rules for Batteries (PEFCR).

Since the publication of the Regulation, it is clear that this is one of the requirements that is generating more interest at national and international level, since manufacturers who want to produce or market their batteries in the European Union, must comply with the declaration of the Carbon Footprint of their product, thus involving an assessment of all stages of production of the product.

This can be complicated due to European dependence on third countries such as China, which not only control the global supply chain for key materials such as lithium, cobalt and graphite, but also perform much of their processing. This presents significant challenges to accurately calculating the carbon emissions associated with battery production, due to the inaccessibility of information. In addition, the complexity of international supply chains requires cooperation and sharing of sensitive (and in most cases confidential) data between multiple actors along the chain.

Due to this, during the last years, several efforts have been made to calculate the Carbon Footprint of different battery technologies, mainly lithium ion. This value depends on several factors such as: the type of technology, its application, the manufacturing process, the size, the energy source used during production, the country where it is produced, the stages of the life cycle that have been included, among others. Therefore, emission ranges vary widely, complicating the task of having a single value.

Analyzing the most relevant studies of recent years, it is established that CO₂ emissions per kWh of lithium ion batteries are in a range between 70 and 170; while for solid state they are between 75 and 120; and for sodium batteries between 80 and 110. In the case of lithium ion batteries, it is the cathode that, as a general rule, contributes between 27 and 39% of the impact.

Implications and strategies for sustainability in the battery industry

Understanding these values is essential for several reasons. On the one hand, it helps to understand the multiple challenges faced by the sector, such as the intensive use of energy, the extraction of critical raw materials, the coordination of actions throughout the value chain, the increase in demand for batteries or the exchange of sensitive information.

In addition, it enables the development of a strategy aimed at both informed decision-making and innovation in design and manufacturing. It also involves transparent disclosure that encourages competition based on environmental performance, developing cleaner and more sustainable technologies that can differentiate themselves in the marketplace.

Addressing these challenges will therefore generate significant opportunities to transform the industry towards more sustainable models and contribute to climate change mitigation through the electrification of mobility, thus producing a close collaboration between all the agents involved.

From CIC energiGUNE we work for the development of sustainable technologies that, in addition to responding to the technical needs of the sector, allow to meet the required sustainability standards. Furthermore, we contribute by helping the different agents in the value chain to adapt to these new technical and sustainability standards, facilitating the transition of our partners towards more sustainable and responsible practices.