Commercial Li-ion batteries are typically cycled between 3.0 and 4.2 V. These voltages limits are chosen based on the characteristics of the cathode (e.g. lithium cobalt oxide) and anode (e.g. graphite). When alternative anode/cathode chemistries are studied the same cut-off voltages are often, mistakenly, used. Silicon (Si) based anodes are widely studied as a high capacity alternative to graphite for Lithium-ion batteries. When silicon-based anodes are paired with high capacity cathodes (e.g. Lithium Nickel Cobalt Aluminium Oxide; NCA) the cell typically suffers from rapid capacity fade. The purpose of this communication is to understand how the choice of upper cut-off voltage affects cell performance in Si/NCA cells. A careful study of three-electrode cell data will show that capacity fade in Si/NCA cells is due to an ever-evolving silicon voltage profile that pushes the upper voltage at the cathode to >4.4 V (vs. Li/Li+). This behaviour initially improves cycle efficiency, due to liberation of new lithium, but ultimately reduces cycling efficiency, resulting in rapid capacity fade

In the quest for a sustainable society, energy storage technology is destined to play a central role in the future energy landscape. Breakthroughs in materials and methods involving sustainable resources are crucial to protect humankind from the most serious consequences of climate change. Rechargeable batteries of all forms will be required to follow the path. Elements that are eligible to harmonically contribute to the development of a sustainable ecosystem and fulfil the demands of high energy density batteries include Na, K, Ca, Mg, Zn, and Al. Numerous research efforts are underway to explore new battery chemistries based on these elements and, depending on the field of application, different elements inherit different advantages and challenges. Full sustainability implies that the environmental friendliness of these systems must be characterized by a “cradle‐to‐grave” approach. In this context, the pursuit of global environmental and economical sustainability from mass production, raw materials, and technical challenges is discussed herein for the most recent battery concepts based on monovalent and multivalent metal anodes. A perspective on strategies and opportunities particularly around the development of all‐solid‐state system configurations is provided, and the most important obstacles to overcome in search of a more sustainable future for electrochemical energy storage are addressed.