The development of high‐capacity, sustainable cathode materials remains a critical challenge in advancing lithium‐ion battery technologies for next‐generation energy storage. Organic electrode materials (OEMs) represent a promising alternative to conventional inorganic cathodes, owing to their composition from earth‐abundant elements and chemically tunable structures that enable high theoretical capacities. Herein, a polyimide‐linked porous organic polymer (HAT‐PTO) is reported to be synthesized via a straightforward hydrothermal reaction from redox‐active hexaazatriphenylene (HAT) and pyrene‐4,5,9,10‐tetraone (PTO) building blocks. The resulting HAT‐PTO framework incorporates multiple redox‐active C═O and C═N centers, delivering a high theoretical capacity of 484 mAh g⁻¹. To overcome limitations in electronic conductivity, hybrid materials are synthesized by in situ growth of HAT‐PTO on multiwalled pristine (CNT) and carboxyl‐functionalized carbon nanotubes (cCNT). Notably, the HAT‐PTO‐cCNT hybrid delivers a high capacity of 397 mAh g⁻¹ at C/10, outstanding rate capability of 225 mAh g⁻¹ at 20 C, and long‐term cycling stability, retaining 171 mAh g⁻¹ after 6000 cycles at 2 C. Ex situ FT‐IR, supported by density functional theory (DFT) calculations, confirms the involvement of both HAT and PTO units in the charge storage mechanism. This work presents a molecular design strategy and scalable synthesis approach toward high‐performance organic cathodes, paving the way for durable, high‐rate lithium‐organic batteries.

Li-ion batteries (LIBs) represent the most sophisticated electrochemical energy storage technology. Nevertheless, they still suffer from safety issues and practical drawbacks related to the use of toxic and flammable liquid electrolytes. Thus, polymer-based solid electrolytes may be a suitable option to fulfill the safety and energy density requirements, even though the lack of high ionic conductivity at 25 °C (10⁻⁸–10⁻⁷ S cm⁻¹) hinders their performance. To overcome these drawbacks, herein, we present an all-solid-state Li-metal full cell based on a three-component solid poly(ethylene oxide)/lithium bis(trifluoromethanesulfonyl) imide/titanium dioxide composite electrolyte that outclasses the conventional poly(ethylene oxide)-based solid electrolytes. Moreover, the cell features are enhanced by the combination of the solid electrolyte with a self-standing LiFePO₄ catholyte fabricated through an innovative, simple and easily scalable approach. The structural, morphological and compositional properties of this system are characterized, and the results show that the electrochemical performance of the solid composite electrolyte can be considerably improved by tuning the concentration and morphology of TiO₂. Additionally, tests performed with the self-standing LiFePO₄ catholyte underline a good cyclability of the system, thus confirming the beneficial effects provided by the novel manufacturing path used for the preparation of self-standing electrodes.

Lithium‐ion batteries (LIBs) are one of the most advanced electrochemical energy storage technologies. However, the increasing demand for LIBs, coupled with problems related to availability and lack of manufacturing centers, has led to lithium market inflation. At this point, sodium‐ion batteries (SIB) represent an economically and environmentally attractive alternative for LIBs. Prussian Blue cathodes (PB) have been extensively studied as cost‐effective materials with volumetric variations that allow the accommodation of sodium ions in the structure. Herein, we present a quasi‐solid Na‐ion cell based on PB cathode and green gel polymer electrolyte (GPE). Nanometric and micrometric PB powders are synthesized and characterized using a wide variety of structural, compositional and electrochemical techniques. The effect of the PB particle size in combination with different electrolytes is investigated. Enhanced cell safety is obtained using a GPE prepared by following a novel green method that avoids using toxic organic solvents. All the tested cells report remarkable electrochemical performance, being the nanometric‐PB/ GPE/ Na cell configuration the one with the highest specific capacity and almost no capacity loss after 100 cycles, outperforming analogous cells assembled with liquid electrolyte. This electrochemical stability is triggered by a robust electrode‐electrolyte interphase.

Sodium-ion batteries (SIBs) are gaining increasing attention due to the abundant availability of sodium. However, the development of suitable electrode materials for SIBs remains a significant challenge. Organic materials such as two-dimensional covalent organic frameworks (2D COFs) have emerged as promising electrodes due to their vast versatility, although their sodium storage mechanism remains poorly understood. In this work, the sodium storage mechanism of a β-ketoenamine anthraquinone-based COF (DAAQ-TFP), employed as a cathode for SIBs, is unveiled through a combination of electrochemical, physicochemical, and computational studies. In contrast with previous studies suggesting a capacitive storage mechanism, our results reveal a combination of pseudocapacitive and faradaic processes. Molecular dynamic simulations combined with ex situ X-ray diffraction studies confirmed that sodium storage occurs via interaction with carbonyl groups located within the COF channels rather than through intercalation between the COF layers. Moreover, electrode calendering experiments demonstrate that the faradaic contribution is governed by the porous COF structure. Finally, the redox inactivity of the carbonyl groups of the β-keto units is demonstrated through both computational and electrochemical measurements. These results further reinforce the role of anthraquinone units as the sole active sites responsible for sodium storage in this type of organic electrode materials.

In today's sustainability‐driven society, the circular economy has emerged as a guiding principle for responsible resource use, aiming to transform production by prioritizing reuse, repair, and recycling, thus extending product lifecycles and reducing waste. Herein, the impact of the circular economy on upcycling, focusing on poly(vinyl butyral) (PVB), widely used as an interlayer in laminated glass, recovered from automotive waste via a patented mechanochemical process, is investigated. For the first time, this process is applied in an innovative closed‐loop design for solid polymer electrolytes (SPEs) in Li–metal batteries (LMBs). A green, solvent‐free method produces polymer blends of PVB, ensuring outstanding mechanical properties, and poly(ethylene oxide) (PEO) as the ion‐conductive matrix. PVB effectively reduces PEO crystallinity, improving ionic conductivity, mechanical strength, and oxidative stability. The resulting SPEs exhibit stable lithium stripping/plating and reduced interfacial resistance in symmetric cells, confirming excellent lithium compatibility. Lab‐scale lithium metal polymer cells with a high‐loading LiFePO ₄ ‐based catholyte (13 mg cm ^{− 2} ) achieve near‐theoretical capacities at low C‐rates (154.4 mAh g ⁻¹ at C/5) and excellent rate performance at 65 °C. By promoting a holistic approach to sustainable resource use, PVB contributes to the development of high‐performance, environmentally sustainable polymer electrolytes for next‐generation LMBs.

Sodium-ion batteries are gaining momentum, and to accelerate their commercial viability, the development of cost-effective and environmentally sustainable materials is crucial. Although hard carbons have been already established as the anodes of choice, several controversies still exist regarding the storage mechanism and interfacial properties during cycling. Here, we present a comprehensive study of a novel hard carbon from licorice root bio-waste by coupling a wide array of physico-chemical techniques, to gain insights into the sodium storage behavior and interfacial properties. Analytical techniques like potentiostatic and galvanostatic intermittent titration were used to assess solid-state sodium-ion diffusion, while ex situ small-angle X-ray scattering and electrochemical impedance spectroscopy modeled with transmission line enabled the monitoring of pore-filling storage evolution during cycling, as well as SEI formation. Staircase potentiostatic electrochemical impedance spectroscopy, and relaxation times analysis was used to further investigate interfacial evolution and charge-transfer kinetics within the initial cycles. While each of these techniques has been previously employed in the study of hard carbons, their combined application to a single material remains relatively uncommon; this work aims at providing a comprehensive and integrated perspective on the electrochemical behavior of licorice-derived hard carbon, highlighting its potential as a sustainable anode material for next-generation sodium-ion batteries.