Electrode Engineering of Redox-Active Conjugated Microporous Polymers for Ultra-High Areal Capacity Organic Batteries

Abstract

Redox-active organic compounds have become promising electrode materials for the development of more sustainable, economical, and safer batteries. However, their high electrochemical performance is inherently associated with the use of low mass-loading electrodes with high carbon content, which collectively hinders their applicability in real batteries. This work presents an innovative approach for developing high-performance and practical organic electrodes through the synthesis of anthraquinone-based conjugated microporous polymers in the presence of carbon nanostructures and further processing into self-supported buckypaper electrodes. This effective method enables high-mass-loading hybrid electrodes (up to 60 mg cm–2) with low carbon content (20 wt %), which attained high gravimetric capacity (83.7 mAh gelectrode –1), high areal capacity (6.3 mAh cm–2), good rate capability (0.8 mAh cm–2 at 10C), and remarkable cycle stability (>80% capacity retention over 1000 cycles). These are the highest values reported for an organic electrode, constituting a great leap forward in the development of practical organic batteries.

Conjugated Microporous Polymers with Bipolar and Double Redox‐Active Centers for High‐Performance Dual‐Ion, Organic Symmetric Battery

“…[29,30] Owing to their low solubility, higher stability, fast electron/ion diffusion, good electronic conductivity and fast kinetics, redox-active CMPs constructed by the redox-active building blocks have attracted much attention as desired energy storage materials. [31][32][33][34][35][36][37] In view of the structural advantage, Pc can be served as both periodic building block and redox-active centers to construct redox-active CMPs. However, the introduction of inactive linking group could result in the high molecular weight and the low capacity.…”

Aqueous zinc batteries: Design principles toward organic cathodes for grid applications

“…As such, we propose that it is critical to assess the cost of the input materials relative to the energy stored over the device lifetime when designing new organic cathode materials for ZIBs. This evaluation may either take the form of a life cycle cost analysis, or may be a quick, approximative assessment used to supplement a scientific publication, as was recently demonstrated by Molina et al. (2020) .…”

Macromolecular Engineering of Poly(catechol) Cathodes towards High-Performance Aqueous Zinc-Polymer Batteries

“…Optimistically, our copolymerization strategy enabled us to push the mass loading to a high value (30 mg cm −2 ), and attained competitive areal capacity of 5.4 mAh cm −2 , which is the highest value reported till date for organic cathodes in AZPBs ( Figure 7 b). This high value of areal capacity is particularly encouraging from the perspective reducing the cost of a practical battery by simultaneously minimizing the inactive components in the battery and maximizing the capacity at the cell level [ 52 ].…”

“…Preparation of RAP/CNTs buckypaper electrodes: We fixed the buckypaper electrode composition of RAP:CNTs to 60:40 wt%. We prepared RAP/CNTs buckypaper electrodes of different mass loadings in the range of 0.5 to 30 mg cm −2 following our recent articles [ 30 , 52 ]. For instance, buckypaper electrode of 2.5 mg cm −2 mass loading is fabricated as following: 28.9 mg of CNTs were dispersed in 20 mL NMP using a tip sonicator, followed by addition of 43.4 mg of RAP, proceeding to sonication for 2 h in a bath sonicator (Branson 2510, 100 W, 42 kHz) and overnight stirring to prepare the electrode ink.…”