31 Mar Cyclocarbonate Monomeric Additives in Lithium-ion Batteries
Pushed by the Battery 2030+ initiative, significant research efforts in the energy sector are dedicated to the improvement of Lithium-ion Batteries (LIBs). Various levers have been identified to improve current technologies such as enhanced sustainability, optimized performances (energy density, cycle life) or improved safety and reliability. All improvement is a step furthers to widespread the use of LIBs in a variety of application fields.
In this field, we actively work on various electrolyte components such as monomers and building blocks bearing ionic moieties, ion-conducting polymers or additives and plasticizers. Within this article, we focus on some interesting electrolytes’ additives, available at SPECIFIC POLYMERS, that can help enhancing Lithium-ion Batteries performances.
Active additives at the interphase!
Chemical reaction that occurs at the interfaces in between the electrolyte and the electrodes are often detrimental to the overall batteries cell performances (continuous electrolyte decomposition, increase of charge-transfer impedance, transition metal dissolution, lower cycling stability and even cell failure). An interesting approach to overcome this issue is to introduce well selected additives in the electrolyte formulation that can lead to in-situ formation of a solid electrolyte interphase (SEI) during the first few cycles of Lithium-ion Batteries. Such protecting layer at the interface enhance the chemical and mechanical stability and can finally reduce or even suppress the electrolyte reactions at the electrode interface at high voltages.
Vinylene carbonate – Additive to promote SEI polymeric layer formation
In this field, vinylene carbonate (VC) was found to be one of the best additives to enhance the performance mainly due to their positive contribution to the CEI (Cathode Electrolyte Interface) formation.  Indeed, VC is reduced during the first cathodic scan at relatively high voltage forming polymeric compounds, which generate a stable and poorly electronically conductive passivation film that hinder solvent decomposition and continuous irreversible consumption of Li ions. Moreover, the flexible VC-based polymeric layer is able to accommodate to slight electrode volume changes.  However, it must be noted that an excessive amount of VC additives in the electrolyte can also bring an increased charge transfer resistance at the anode. It is then recommended in the literature to carefully dosed the VC content into the electrolyte around 1-2%wt.
What about other monomeric cyclocarbonates to promote SEI formation?
Related to this field of research, SPECIFIC POLYMERS proposes three polymerizable cyclocarbonate additives that can play a similar role than VC.
Both cyclocarbonate monomers are similar to VC since they combine a polymerizable moiety together with a cyclocarbonate ring. The main differences are the chemical natures of the polymerizable function and linkers. In the case SP-60-001 (Allyl glycidyl cyclocarbonate), an allyl function is linked to the cyclocarbonate moiety through an ether linker whereas, in the case of SP-40-001 (Glycerol carbonate methacrylate), the reactive double bond is a methacrylate and the linker an ester function. These variations could impact the formation kinetic of the SEI as well as its chemical stability and mechanical properties. All these three cyclocarbonates monomers are sold by SPECIFIC POLYMERS. What if you try and evaluate them – Let’s challenge vinylene carbonate!
Did you know?
SPECIFIC POLYMERS is highly involved in the research field of batteries and more especially in the design of building-blocks, monomers and polymers of interest for battery electrolytes. Our R&D activity is mainly geared toward the synthesis of (i) monomeric and polymeric salts that can be used in the design of single lithium-ion conducting polymer electrolyte, (ii) ion-conductive polymers (poly(ethylene glycol) based, polycarbonates based, etc.) bearing specific moieties that help improving lithium conductivity, enhance interfaces compatibility, limit transference or avoid dendrites growth and (iii) additives and plasticizers that aim favoring the overall performances of the
In addition, SPECIFIC POLYMERS is a member of two consortium linked to this research area: European Battery Alliance (EBA) and Battery 2030.
Related sci. publications
- Publication in Journal of Power Sources from S. Grugeon and coworkers entitled: “Towards a better understanding of vinylene carbonate derived SEI-layers by synthesis of reduction compounds” >
- Publication in Journal of the American Chemical Society from Yanting Jin and coworkers entitled : “Understanding Fluoroethylene Carbonate and Vinylene Carbonate Based Electrolytes for Si Anodes in Lithium Ion Batteries with NMR Spectroscopy” >
- Publication in Electrochemistry Communications from Yi-HungLiu and coworkers entitled : “An approach of evaluating the effect of vinylene carbonate additive on graphite anode for lithium ion battery at elevated temperature” >