Self-Healing: An Emerging Technology for Next-Generation Smart Batteries

Complex battery degradation is an interplay of different processes correlated to the thermodynamic, chemical, and mechanical instability of materials. Their degradation kinetics and mechanisms are functions of several intrinsic and environmental conditions. The degradation of the battery cell can be minimized by using preventive steps, like artificial interphases, coatings, additives, or materials that operate within the thermodynamic stability voltage window. Like in most systems/applications degradation processes/aging cannot be avoided since battery cells operate in different environments. Self-healing functionalities have been proved in different areas of material science and they can significantly improve the performance of battery cells. Some of them have been demonstrated on the laboratory scale, while other degradation processes have been tackled only by the development of preventive approaches. Since self-healing functionalities add additional weight and cost to the battery cell, directions of development should be focused on modification of nonactive materials, preferably based on biosourced materials to lower environmental impact. Important issues include detection of degradation using sensors and the vectorization of self-healing components and their controlled release. In addition to this, a triggering process of extrinsic self-healing components together with manufacturability and recyclability should be considered from the early stages of the development phase.