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Various electrolyte additives are developed to construct a cathode electrolyte interphase (CEI) layer for high‐voltage LiCoO2 since the cathode suffers severe interfacial degradation when increasing the cut‐off voltage over 4.55 V. However, the CEI derived from the additive sacrificial reaction faces the risk of rupture due to the corrosion reaction and the volumetric variation of the cathode. Herein, a non‐passivating cathode interface is realized for 4.6 V LiCoO2 with a non‐sacrificial electrolyte additive (TBAClO4) by regulating the solvent environment at the interface rather than the preferential decomposition for CEI formation. Owing to the novel protection mechanism, the cell performance shows little dependence on the CEI‐formation process. Therefore, an ultra‐high initial coulombic efficiency (96.63%) and excellent cycling stability (81% capacity retention after 300 cycles) are achieved in Li||LiCoO2 batteries. Moreover, even with the electrolyte containing 1000 ppm H2O, the remarkable water capture ability of the additive together with its interfacial regulation enables the 4.6 V Li||LiCoO2 battery to retain 80% capacity after 200 cycles. This non‐sacrificial strategy provides new insights into high‐voltage electrolyte additive design for high‐energy‐density lithium metal batteries. [ABSTRACT FROM AUTHOR]

Potassium ion batteries using graphite anode and high‐voltage cathodes are considered to be optimizing candidates for large‐scale energy storage. However, the lack of suitable electrolytes significantly hinders the development of high‐voltage potassium ion batteries. Herein, a dilute (0.8 m) fluorinated phosphate electrolyte is proposed, which exhibits extraordinary compatibility with both graphite anode and high‐voltage cathodes. The phosphate solvent, tris(2,2,2‐trifluoroethyl) phosphate (TFP), has weak solvating ability, which not only allows the formation of robust anion‐derived solid electrolyte interphase on graphite anode but also effectively suppresses the corrosion of Al current collector at high voltage. Meanwhile, the high oxidative stability of fluorinated TFP solvent enables stable ultrahigh‐voltage (4.95 V) cycling of a potassium vanadium fluorophosphate (KVPO4F) cathode. Using TFP‐based electrolyte, the 4.9 V‐class potassium ion full cell based on graphite anode and KVPO4F cathode shows rather remarkable cycling performance with a high capacity retention of 87.2% after 200 cycles. This study provides a route to develop dilute electrolytes for high‐voltage potassium ion batteries, by utilizing solvents with both weak solvating ability and high oxidative stability. [ABSTRACT FROM AUTHOR]

In the article "Non-Sacrificial Additive Enables a Non-Passivating Cathode Interface for 4.6 V Li||LiCoO2 Batteries," researchers Guang Feng, Dengyun Zhai, Feiyu Kang, and their colleagues propose a new method to stabilize a 4.6 V LiCoO2 cathode in lithium metal batteries. By using a non-sacrificial electrolyte additive, they are able to regulate the solvent environment at the cathode interface, reducing interfacial side reactions and improving the cycle life of the batteries. This research offers a promising approach to enhance the performance of high-voltage lithium-ion batteries. [Extracted from the article]

The development of sodium metal batteries has long been impeded by dendrite formation issues. State-of-the-art strategies, exemplified by sodiophilic hosting/seeding layers, have demonstrated great success in suppressing dendrite formation. However, addressing high-capacity applications (>10 mAh cm -2 ) remains a significant challenge. Herein, the study revisits the interlayer strategy by simply covering a carbon nanotube (CNT) film onto the surface of a sodium metal anode, unlocking its overlooked potential for ultrahigh capacity applications. In situ Raman spectroscopy reveals the interlayer's fast-ion-storage feature, enabling deposition at the interface without capacity limitations. Consequently, in symmetric cells, one-year long-term reversible cycling and a record-high capacity of 50 mAh cm -2 under 90% depth of discharge is achieved, representing a significant breakthrough for stabilizing Na anode. Furthermore, the full cell with a 50-µm thin metal anode and a high-loading Na 3 V 2 (PO 4 ) 3 cathode (12 mg cm -2 ) delivers a stable capacity of 94 mAh g -1 for 270 cycles (94% capacity retention)., (© 2024 Wiley‐VCH GmbH.)

Understanding the electrochemical property of superoxides in alkali metal oxygen batteries is critical for the design of a stable oxygen battery with high capacity and long cycle performance. In this work, a KO 2 -decorated binder-free cathode is fabricated by a simple and efficient electrochemical strategy. KO 2 nanoparticles are uniformly coated on the carbon nanotube film (CNT-f) through a controllable discharge process in the K-O 2 battery, and the KO 2 -decorated CNT-f is innovatively introduced into the Li-O 2 battery as the O 2 diffusion electrode. The Li-O 2 battery based on the KO 2 -decorated CNT-f cathode can deliver enhanced discharge capacity, reduced charge overpotential, and more stable cycle performance compared with the battery in the absence of KO 2 . In situ formed KO 2 particles on the surface of CNT-f cathode assist to form Li 2 O 2 nanosheets in the Li-O 2 battery, which contributes to the improvement of discharge capacity and cycle life. Interestingly, the analysis of KO 2 -decorated CNT-f cathodes, after discharge and cycle tests, reveals that the electrochemically synthesized KO 2 seems not a conventional electrocatalyst but a partially dissolvable and decomposable promoter in Li-O 2 batteries.

Background: Mactra veneriformis, a typical marine bivalve mollusk, delicious sea food while low cost, is ubiquitous and abundant in Chinese coastal areas, especially in the coastal shoals of Jiangsu province. To our knowledge, previously reported analytical methods can not meet a set of quality control., Objective: For the simultaneous determination of eight components (uridine, inosine, guanosine, thymidine, adenosine, xanthine, thymine and hypoxanthine) in M. veneriformis, a high performance liquid chromatography with UV detector method was established., Materials and Methods: To develop the method, a reverse phase column, BioBasic-C18 (5 μm, 4.6 mm × 250 mm) was used. The mobile phase consisted of methanol and water using a gradient elution. The UV wavelength was set at 245 nm. The analysis conditions including extraction methods, extraction solvents, and HPLC parameters were optimized systematically for achieving good separation. Linearity, accuracy, repeatability and detection limit was revealed and showed good performance., Results: The optimized HPLC method was successfully applied for the qualititation of 5 nucleosides namely, uridine, inosine, guanosine, thymidine, adenosine and 3 nucleobases namely, xanthine, thymine, hypoxanthine in M. veneriformis., Conclusion: A method with less time-consuming, more sensitive, and more precise was developed for the quantitative determination of nucleosides and nucleobases in M. veneriformis extractions. The established method might apply as an alternative approach for the quality assessment of M. veneriformis.

Background: Schisandra chinensis, one of the well-known traditional Chinese herbal medicines, is derived from the dry ripe fruits of Schisandra chinensis (Turcz.) Baill. according to the 9th China Pharmacopeia. Lignans are the main components isolated from extracts of S. chinensis and their content varies depending on where S. chinensis was collected. We have established a qualitative and quantitative method based on the bioactive lignans for control of the quality of S. chinensis from different sources., Materials and Methods: To develop a high-performance liquid chromatography method, an Elite ODS C18 column (250 mm Χ 4.6 mm, 5μm) at a column temperature of 30°C and flow rate of 1.0ml/min using acetonitrile (A) and water (B) as the mobile phase with a linear gradient and the peaks were monitored at 217 nm., Results: All calibration curves showed good linearity (r ≥ 0.9995) within test ranges. This method showed good repeatability for the quantification of these eleven components in S. chinensis with intra- and inter-day relative standard deviations less than 0.43% and 1.21%, respectively. In the recovery test, results of accuracy ranged from 99.51% to 101.31% with RSD values less than 2., Conclusion: The validated method can be successfully applied to quantify the eleven investigated components in 22 samples of S. chinensis from different sources.