Energy & Environmental Science最新文献

Sodium-ion batteries (SIBs) present a resource-sustainable and cost-efficient paradigm poised to overcome the limitation of relying solely on lithium-ion technologies for emerging large-scale energy storage. Yet, the path of SIBs to full commercialization is hindered by unresolved uncertainties regarding thermal safety and lingering debates over the origin of thermal runaway. Herein, through multiscale equivalent analysis from Ah-grade cells to microstructures of battery components, we probe that the difference in the chemical environment for cation storage in anodes is the mechanistic origin underlying the inferior thermal safety of SIBs compared to lithium-ion batteries (LIBs). Bearing a quasi-metallic nature, sodium clusters that form in hard carbon (HC) anodes during routine sodiation predominantly initiate cell self-exothermic reactions, significantly earlier than the decomposition of the solid–electrolyte interphase (SEI) typically observed in LIBs. Solid-state NMR measurements elucidate that clustered sodium in HC exhibits electronic properties more akin to metallic states than lithium in graphite, with even higher electron state densities at the Fermi level than bulk sodium. This heightened reactivity triggers the decomposition of linear carbonates, ultimately culminating in a thermal runaway event almost on par with scenarios involving sodium plating. Our work challenges the prevailing brief that the thermal safety insights between LIBs and SIBs are interchangeable and highlights the necessity of stabilizing deeply sodiated HC for practically safe sodium-based battery chemistries.

It is now well-known that moderate amounts of lead iodide (PbI₂) in organic–inorganic hybrid perovskite films are capable of passivating defects and stabilizing the material. However, contrarily, excessive PbI₂ instead leads to rapid degradation and thus destabilizes the perovskite solar cells (PSCs). To address this challenge, we propose to use melamine (MEA) additive to control the concentration of PbI₂ in perovskite films fabricated with sequential deposition method. As demonstrated by our calculations and NMR measurement results, MEA has both donor and acceptor regions which combine well with the PbI₂'s surface topology: the triazine core units are capable of binding to uncoordinated lead while the amino groups of MEA are capable of coordinating with the iodide anions and effectively “trichelate” PbI₂, thus passivating the defects and promoting carrier separation. Furthermore, the simultaneous introduction of MEA and cesium iodide regulated the crystallization of perovskite films, improved the degree of (111) crystal orientation, and enabled the formation of high-quality perovskite films without pinholes. As such, based on the synergistic effect of MEA and cesium iodide, we prepared inverted PSCs by sequential deposition method with a PCE of 25.66% (certified at 25.06%) and high V_OC approaching 1.2 V with a steady state PCE of 25.19%. The optimized device can maintain more than 90% of the initial efficiency at the maximum power point for 1000 h. In addition, through this strategy, we also prepared a flexible device with an efficiency of up to 24.03%, which can maintain more than 90% of the initial performance after 5000 bending cycles, thus demonstrating an excellent mechanical stability.

Zinc–iodine batteries (ZIBs) have long struggled with the uncontrolled spread of polyiodide in aqueous electrolytes, despite their environmentally friendly, inherently safe, and cost-effective nature. Here, we present an integral redesign of ZIBs that encompasses both the electrolyte and cell structure. The developed self-sieving polyiodide-capable liquid–liquid biphasic electrolyte can achieve an impressive polyiodide extraction efficiency of 99.98%, harnessing a meticulously iodine-containing hydrophobic solvated shell in conjunction with the salt-out effect. This advancement facilitates a membrane-free design with a Coulombic efficiency of ∼100% at 0.1C, alongside an ultra-low self-discharge rate of ∼3.4% per month and capacity retention of 83.1% after 1300 cycles (iodine areal loading: 22.2 mg cm⁻²). Furthermore, the integrated cell structure, paired with the low-cost electrolyte ($4.6 L⁻¹), enables rapid assembly into A h-level batteries within hours (1.18 A h after 100 cycles with a capacity retention of 86.7%), supports electrolyte regeneration with ∼100% recycling efficiency, and extends to ZIBs with a two-electron iodine conversion reaction. This endeavor establishes a novel paradigm for the development of practical zinc–iodine batteries.

Perovskite solar cells (PSCs) as new-generation photovoltaic cells have received remarkable interest due to the facile fabrication procedures and superb power conversion efficiencies (PCEs). Nevertheless, the widely used noble metal-based rear electrodes such as Ag and Au in PSCs suffer from the relatively high material costs and instability induced by the halide anion degradation reaction, strongly hindering the practical applications of PSCs. Consequently, carbon-based materials are considered as some of the most encouraging candidates to substitute noble metals as rear electrodes due to the cost effectiveness, superior physical/chemical stability, superb structural flexibility and diverse/easily tuned properties to realize low-cost and highly robust PSCs. However, the carbon electrode-based PSCs still suffer from the much inferior PCEs to those of the noble metal-based counterparts due to the insufficient carrier transfer capability and inferior interface contact. In this paper, the recent advancements in the design and fabrication of advanced carbon-based rear electrodes for low-cost and efficient PSCs are reviewed by highlighting the unique merits of carbon-based rear electrodes over metal/metal oxide-based counterparts. Several distinct strategies are also proposed to improve the PCEs and durability of carbon electrode-based PSCs. Lastly, the current challenges and future directions of carbon-based rear electrode-based PSCs are also highlighted and discussed, intending to present vital insights for the future development of low-cost carbon-based PSCs towards the scalable production and widespread applications of this technology.

Lithium-ion batteries (LIBs) are highly sensitive to cycling conditions and show a nonlinear degradation pattern, typically noticeable in later stages. This affects the accuracy of most battery health prognostic models, especially those relying on long-term data collected under varying operational conditions. To tackle these challenges, we propose using statistical features extracted from the battery surface temperature during the first 10 cycles and developing a data-driven machine learning (ML) model for early-cycle lifetime prediction. Models are trained on each of the selected open-source datasets comprising 223 LIBs and tested on their respective datasets with non-stratified data splits using a balanced ratio. These datasets include lithium iron phosphate (LFP), nickel cobalt aluminum oxide (NCA), and nickel manganese cobalt oxide (NMC) cells, tested under different environmental temperatures and cycling protocols. In one comprehensive dataset, our model achieved competitive performance compared to state-of-the-art studies that rely on features extracted from much longer cycling data—up to ten times the duration. This work provides valuable insights into the strong correlation between early-cycle surface temperature and battery lifetime across various battery chemistries, cycling rates, and environmental temperatures.

Electrochemical reactors can reduce the carbon intensity of cement production by using electricity to convert limestone (CaCO₃) into Ca(OH)₂, which can be converted into cement clinker by reacting with silica (SiO₂) at high temperatures. A key challenge with electrochemical reactors is that the deposition of solid Ca(OH)₂ at the membrane leads to unacceptably low energy efficiencies. To address this challenge, we connected the electrochemical reactor used for limestone calcination (“cement electrolyser”) to a distinctive chemical reactor (“calcium reactor”) so that Ca(OH)₂ forms in the calcium reactor instead of within the electrochemical reactor. In this tandem system, the cement electrolyser generates H⁺ and OH⁻ in the respective chemical and cathode compartments. The H⁺ then reacts with CaCO₃ to release Ca²⁺, which is diverted into the calcium reactor to react with the OH⁻ to form Ca(OH)₂. We fabricated a composite membrane to selectively block the transport of Ca²⁺ into the cathode compartment. Charge balance in the cement electrolyser was enabled with monovalent ions (e.g., K⁺) as the positive charge carrier. This orthogonalized ion management was validated by operando imaging. The tandem reactor enabled the electrolysis process to operate for 50 hours at 100 mA cm⁻² without any voltage increase, which represents a meaningful step forward for electrochemical cement clinker precursor production.