Lithium ion batteries (LIBs) are one of the most promising electrochemical energy storage technologies today. This is due to its high energy density, high voltage, low weight and minimal memory effect. LIBs are currently used in everyday devices, such as mobiles or electric cars. Even so, and despite their great potential and application, they present significant problems associated to sustainability issues. For instance, commercial LIBs rely on electrode materials based on inorganic elements that are very scarce in the Earth's crust (Lithium, Cobalt, among others) and are geographically located in a few countries with perilous mining conditions.
Organic batteries, based on organic active materials, are a promising and sustainable alternative that have attracted the interest of scientific community in the last few years. These compounds have interesting characteristics, such as low price, environmentally friendly and great versatility. Researchers from all over the world are focusing their research on a multitude of organic compounds, from small molecules to large polymers with different structures and models. One of the most promising compounds is redox conjugated microporous polymers (RCMPs). These RCMPs combines the advantages associated to their organic nature together with a three-dimensional porous structure that facilitates ion diffusion and electronic transfer within the battery.
Using a promising approach, researchers from Electrochemical Processes Unit in collaboration with Photoactivated Processes Unit of IMDEA Energy Institute have recently published an interesting article* in Advanced Functional Materials. We have developed a new anthraquinone‐based conjugated microporous polymer that is easy to disperse, enabling the fabrication of high‐quality electrodes tested as cathode for high performance lithium ion batteries. The reported redox microporous polymer exhibits ultra‐high specific surface area (>2000 m2 g−1) with dual micro‐mesoporosity. These interesting textural properties and the inherent robustness of conjugated porous polymers contribute to their excellent electrochemical performance such as high gravimetric capacity (100 mAh g‒1), excellent rate capability (50% capacity retention at 30 C) and unprecedented long-term cyclability, retaining 58% of its initial capacity over more than 80 000 cycles at 30 C.
(*) Molina, N. Patil, E. Ventosa, M. Liras, J. Palma and R. Marcilla, “New Anthraquinone-based Conjugated Microporous Polymer Cathode with Ultrahigh Specific Surface Area for High-Performance Lithium-ion Batteries“ Advanced Functional Materials (2019) 1908074. https://doi.org/10.1002/adfm.201908074