Self-Healing Polymer Electrolytes for Next-Generation Lithium Batteries

Abstract

The integration of polymer materials with self-healing features into advanced lithium batteries is a promising and attractive approach to mitigate degradation and, thus, improve the performance and reliability of batteries. Polymeric materials with an ability to autonomously repair themselves after damage may compensate for the mechanical rupture of an electrolyte, prevent the cracking and pulverization of electrodes or stabilize a solid electrolyte interface (SEI), thus prolonging the cycling lifetime of a battery while simultaneously tackling financial and safety issues. This paper comprehensively reviews various categories of self-healing polymer materials for application as electrolytes and adaptive coatings for electrodes in lithium-ion (LIBs) and lithium metal batteries (LMBs). We discuss the opportunities and current challenges in the development of self-healable polymeric materials for lithium batteries in terms of their synthesis, characterization and underlying self-healing mechanism, as well as performance, validation and optimization.

Solvent and catalyst free vitrimeric poly(ionic liquid) electrolytes

“…Thus, introducing self-healing functionality in PE additionally enhances a life-time of LiBs. 8 Furthermore, PEs provide improved mechanical properties and offer the possibility to create batteries with specific shapes and designs suitable for wider range of application. Features of polymeric materials can be tuned in a way to make them suitable for application in additive manufacturing of LiBs.…”

“…Introducing self-healing abilities in electrolytes proved to extend the cyclic lifetime of the battery. 8,[18][19][20] This can be achieved via incorporating dynamic covalent or noncovalent supramolecular bonds/interactions between polymer chains. Noncovalent bonds/interactions are classically hydrogen bonding, ionic interaction, pi-pi stacking etc.…”

“…Noncovalent bonds/interactions are classically hydrogen bonding, ionic interaction, pi-pi stacking etc. 8,20,21 Polymers crosslinked via dynamic covalent bonds are known as vitrimers (also referred as dynamic covalent network (DCN) or covalent adaptable network (CAN) polymers) and represent a relatively new class of materials. [22][23][24] According to their nature vitrimers are situated between thermosets and thermoplastics, allowing reprocessing or reshaping above threshold temperatures without losing their initial properties.…”

Catalyst-Free, Mechanically Robust, and Ion-Conductive Vitrimers for Self-Healing Ionogel Electrolytes

“…Successful attempts have been made using disulfide bonds 16,17,29 and boric esters 30−32 for generating self-healing all-solid-state polymer electrolytes. 1,33 However, there are very few reports on vitrimer-based self-healable GPEs, placing the application of vitrimers into mechanically robust and self-healable GPEs that can withstand fragmentation during charging and discharging still as a major challenge.…”

“…Such external catalysts, often Lewis or Bro̷nsted acids, strong bases, transition metals, or nucleophilic reagents, can result in catalyst aging, oxidation, or even degradation under charging and discharging-cycles. ,,− Therefore, there is a high demand for catalyst-free vitrimers in PE applications. Successful attempts have been made using disulfide bonds ,, and boric esters − for generating self-healing all-solid-state polymer electrolytes. , However, there are very few reports on vitrimer-based self-healable GPEs, placing the application of vitrimers into mechanically robust and self-healable GPEs that can withstand fragmentation during charging and discharging still as a major challenge.…”