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Abstract In recent decades, cathode materials, significant in both liquid and solid-state lithium-ion and beyond-lithium batteries, are essential for global sustainability due to their unique redox and ionic transport properties. The mass production of cathodes to keep pace with electrochemical energy storage demand has increasingly come under scrutiny. However, the environmental impacts, specifically emissions and waste produced during the synthesis and surface treatment of these materials, have largely been overlooked, even in laboratory settings. This perspective addresses this gap by discussing the importance of adopting entirely dry, waste-free processes for cathode material production. We summarize recent advances in both physical and chemical dry processing techniques and outline potential future research directions in this domain, emphasizing their significance for sustainable battery manufacturing. 

LiMn_0.6Fe_0.4PO₄has attracted attention as a promising, high-energy, and cost-effective alternative to LiFePO₄(LFP) for lithium-ion batteries. However, its thermal stability, especially at full cell level, remains less understood compared to LFP. This study compares the cycling performance and thermal stability of LiMn_0.6Fe_0.4PO₄/graphite and LFP/graphite pouch cells using a consistent electrolyte formulation: 1.2 m lithium bis(fluorosulfonyl)imide (LiFSI) in ethylene carbonate (EC):ethyl methyl carbonate (EMC):dimethyl carbonate (DMC) (25:5:70 by volume) with 2 wt% vinylene carbonate (VC). Thermal stability was evaluated with two ∼250 mAh pouch cells through accelerating rate calorimetry at elevated temperatures. After roughly 275 cycles at C/3 and 40 °C, the LFP/graphite cells retained 91% of their initial capacity, while LMFP/graphite cells retained 89%, indicating slightly better electrochemical stability for LFP cells. Exothermic reactions in LMFP cells initiated around 125 °C, compared to 140 °C for LFP, implying higher thermal vulnerability. Despite this, both cell types exhibited similar self-heating rates below 0.1 °C min⁻¹, demonstrating strong safety performance. Overall, although LMFP offers a higher voltage window, its thermal stability and cycling performance still slightly lag behind LFP. 

Rates and directions of crustal extension in a continental rift vary in time and space as the rift evolves, and these geologic records are often preserved along fault planes. Some fault-kinematic studies have been undertaken in the central to northern segments of the Rio Grande rift, but similar studies from the southern part of the Rio Grande rift of western Texas, USA, and northern Mexico are fewer. We present new fault-kinematic data from six locations in the southern Rio Grande rift of Trans-Pecos Texas, combined with U-Pb dating of calcite slickenlines, to constrain the directions and time scales of extension. All locations preserve NE-SW−oriented extension, and locations within the Sunken Block graben preserve a more complex kinematic history of multiple extension directions. Four U-Pb ages range from 30.1 ± 3.1 Ma to 13.7 ± 0.9 Ma. Combined with fault-kinematic data and assuming a constant stress regime between 30 Ma and 14 Ma, these data support the interpretation that earliest extension in the southern rift was oriented NE-SW, and extension rotated clockwise to E-W and NW-SE after 13.7 ± 0.9 Ma. Based on available data, this rotation was broadly coincident with rotation in the extension direction in the southern Española basin and in the Basin and Range Province. These differences suggest that extension in the Rio Grande rift responded to the evolving western boundary of the North American plate but included initial underlying driving forces that were supplanted by lateral forces as the transform margin lengthened. Additionally, geochronologic and kinematic data across the Sunken Block graben of the southern Rio Grande rift indicate that the locus of rifting concentrated with time toward the center of this basin; such structural narrowing has previously been demonstrated in the northern segment of the rift. This study provides a much-needed comparison between the southern and northern segments of the rift but highlights the need for more collection of combined kinematic and geochronologic data. 

A multiphysics study evaluates the mechanical–electrochemical–thermal response and fundamental mechanisms of SIBs under mechanical abuse, explores key safety parameters, and compares the safety of SIBs and LIBs under mechanical loading. 

Sodium-ion batteries (SIBs) with Earth-abundant elements are promising for global electrification, but electrolyte stability impacts electrochemical performance and safety. This study compares non-fluorinated 1,2-diethoxyethane (DEE) and fluorinated 1,2-bis(2,2-difluoroethoxy)ethane (F4DEE) as electrolyte solvents in Na_0.97Ca_0.03[Mn_0.39Fe_0.31Ni_0.22Zn_0.08]O₂(NCMFNZO)/hard carbon (HC) pouch cells up to 4.0 V. Fluorination slightly reduces ionic conductivity and increases viscosity but significantly enhances electrochemical stability and safety. Cells with F4DEE exhibit lower impedance, reduced gas evolution, and less voltage decay during high-voltage storage at 40 °C. Long-term cycling shows ∼85% capacity retention after 500 cycles at 25 °C and ∼80% at 40 °C with less transition metal dissolution, outperforming DEE-based cells. Isothermal microcalorimetry reveals lower parasitic heat generation with F4DEE, while soft X-ray absorption spectroscopy confirms stabilized Ni and Mn oxidation states, indicating suppressed electrolyte oxidation. Accelerating rate calorimetry reveals improved thermal stability with F4DEE. These findings highlight fluorinated ether solvents as a promising approach to enhance SIB lifespan and safety, with ongoing challenges requiring further solvent and additive optimization. 

Traditional linear carbonates including dimethyl carbonate (DMC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC) were investigated as co-solvents for the dimethyl-2,5-dioxahexane carboxylate (DMOHC)-based electrolyte in Na_0.97Ca_0.03[Mn_0.39Fe_0.31Ni_0.22Zn_0.08]O₂(NCMFNZO)/hard carbon (HC) pouch cells. The EMC-containing cell displays excellent electrochemical performance, exhibiting only a 1.6 mAh irreversible capacity loss during 500 h of storage at 4 V and 40 °C, and maintaining over 80% capacity retention after 200 cycles up to 4 V at 40 °C. Severe gas evolution and Na plating issues are present in all the tested systems.