Zhigao Huang

Fire detection in warehouse scenarios is challenged by complex background interference, weak features of small flame targets, and indistinct flame textures, which can reduce detection performance and constrain model deployment. To address these issues, we propose FC-YOLO (Fire Complexity-YOLO), a lightweight fire detection algorithm based on YOLOv11n. A dynamic upsampling module (DySample) is introduced into the neck network to adaptively adjust feature sampling locations and reduce information loss. An adaptive downsampling module (ADown) is employed in the backbone and neck networks to reduce computational complexity while enabling efficient multi-scale feature extraction. A residual multi-scale attention module (IEMA) is constructed in the neck network to enhance feature representation and focus on critical regions. Finally, an additional small-object detection layer (P2) is introduced to improve small-flame detection. On a self-built flame dataset, FC-YOLO achieves 91.8% precision, 84.7% recall, 90.1% mAP@0.5, and 50.0% mAP@0.5:0.95 with 2.2M parameters. Compared with YOLOv11n, these metrics improve by 1.8%, 4.6%, 2.4%, and 3.7%, respectively, while parameters decrease by 14%. These results demonstrate that FC-YOLO improves detection performance and robustness in complex fire scenarios while maintaining a lightweight architecture, indicating strong potential for deployment on edge devices.

Lithium cobalt oxide (LiCoO2, LCO) is constrained by a 4.2 V cutoff, delivering an actual capacity of only about 60% of its theoretical value. Raising voltage to 4.5 V boosts capacity but triggers interfacial reactions, oxygen loss, and harmful phase transitions, causing rapid degradation. In this study, an ~5 nm-thick Al2O3 surface layer was deposited on LCO via powder magnetron sputtering. This nanoscale coating markedly enhances electrochemical performance: after 300 cycles at 5C, LCO-A2 retains 81.1% capacity, whereas pristine LCO completely loses electrochemical activity within 200 cycles. After 200 cycles at 1C within 3.0–4.5 V, LCO-A2 maintains 84.6% capacity. Even under the harsh combined conditions of 45 °C and 4.5 V, its capacity retention reaches 86.9% after 200 cycles, far surpassing the 39.5% of pristine LCO. The results demonstrate that the thin Al2O3 surface layer effectively suppresses side reactions between Co4+ and the electrolyte, mitigates detrimental phase transitions and microcracking, and improves lithium-ion transport kinetics, thereby synergistically enhancing high-rate capability and long-term cycling stability. This strategy successfully reconciles an electronically insulating coating with high-rate performance and long-term cycling stability, providing a viable approach for interface engineering of LCO cathodes targeting 4.5 V-class applications.

Li-alloy anodes have emerged as promising alternatives to the Li metal for all-solid-state batteries (ASSBs) due to their ability to mitigate interfacial side reactions and suppress dendrite growth. However, Li-ion diffusion limitation at the alloy/electrolyte interface remains a challenge. Herein, we propose a work function-tunable Li–Ag alloy design to reduce the electrostatic barrier at the Li–Ag/β-Li3PS4 interface based on a first-principles-informed thermodynamic model. Our calculations show that among Li–Ag alloys, Li-rich phases Li3Ag and Li11Ag2 exhibit ultralow Li diffusion barriers (∼0.1 eV) and favorable Li vacancy formation energies, enabling rapid Li diffusion. Our analysis of work functions of Li–Ag alloys as functions of orientation and termination reveals that surface termination is the primary determinant, with orientation playing a secondary role. A Li-terminated surface substantially lowers the work function, thereby reducing the interfacial potential drop and promoting Li-ion transport. While the influence of orientation is comparatively minor, its optimization can further reduce the barrier. Notably, the Li3Ag phase with a Li-terminated (111) surface achieves an interfacial potential drop as low as 0.20 V, much lower than that of the Ag-terminated (111) surface. Our findings highlight surface termination as a critical design principle and suggest that synergistic optimization of alloy composition, termination, and orientation is essential to minimize interfacial barriers in ASSBs.

Analog electrochemical memories provide ionic control of conductance for neuromorphic computing, but reliable retention of programmed states remains a critical challenge. Here we report a three-terminal Li-based electrochemical random-access memory (Li-ECRAM) consisting of a LiCoO2 channel, a mechanically buffered and moisture protective SiOx ion reservoir and a LiPON interlayer. The device supports 64 distinguishable conductance states and maintains representative programmed states over 103 s at temperatures up to 80 °C and 80% relative humidity. First-principles-informed thermodynamic analysis indicates that LiPON adjusts the interface band alignment and the interfacial electrostatic potential. This interface potential redistribution suppresses lithium migration and parasitic electronic transport, stabilizing the lithium–vacancy profile in LiCoO2. The Li-ECRAM exhibits paired pulse facilitation, excitatory and inhibitory postsynaptic currents, and long-term potentiation and depression with nonlinearity factors of αP = 0.501and αD = 0.826, while keeping cycle-to-cycle variation below 0.4% and device-to-device variation at 0.52%. When the measured conductance updates are mapped into a YOLOv5 fire detection network, the system reaches a mean average precision of 76.7%, or 91.1% of the software performance. These results identify LiPON/SiOx synergistic channel–reservoir interface regulation as a route to environmentally stable Li-ECRAM synapses.

Lithium cobalt oxide (LiCoO2, LCO) is constrained by a 4.2 V cutoff, delivering an actual capacity of only about 60% of its theoretical value. Raising voltage to 4.5 V boosts capacity but triggers interfacial reactions, oxygen loss, and harmful phase transitions, causing rapid degradation. In this study, an ~5 nm-thick Al2O3 surface layer was deposited on LCO via powder magnetron sputtering. This nanoscale coating markedly enhances electrochemical performance: after 300 cycles at 5C, LCO-A2 retains 81.1% capacity, whereas pristine LCO completely loses electrochemical activity within 200 cycles. After 200 cycles at 1C within 3.0–4.5 V, LCO-A2 maintains 84.6% capacity. Even under the harsh combined conditions of 45 °C and 4.5 V, its capacity retention reaches 86.9% after 200 cycles, far surpassing the 39.5% of pristine LCO. The results demonstrate that the thin Al2O3 surface layer effectively suppresses side reactions between Co4+ and the electrolyte, mitigates detrimental phase transitions and microcracking, and improves lithium-ion transport kinetics, thereby synergistically enhancing high-rate capability and long-term cycling stability. This strategy successfully reconciles an electronically insulating coating with high-rate performance and long-term cycling stability, providing a viable approach for interface engineering of LCO cathodes targeting 4.5 V-class applications.

Mitigating the severe volume expansion of silicon (Si) anodes and developing scalable, low-cost fabrication processes are critical for commercializing high-energy-density batteries. Herein, ZnO-modified microspherical composite anode (F-Gr@Si/C/ZnO) using commercial Si powder and flaky graphite as raw materials has been constructed. The synthesis integrates efficient sand-milling pretreatment with spray drying and sintering. This rational design leverages spray drying to uniformly coat PVP and zinc acetate onto the Si/graphite surfaces. During subsequent annealing, PVP undergoes in-situ carbonization while zinc acetate decomposes into ZnO nanoparticles, jointly forming a highly uniform composite protective layer. The resulting F-Gr@Si/C/ZnO composite delivers exceptional electrochemical performance, retaining 717 mAh g-1 after 1000 cycles at 1 A g-1 (91.6% retention). Even at a high rate of 2 A g-1, a capacity of 502.6 mAh g-1 is preserved over 1000 cycles. Furthermore, LCO||F-Gr@Si/C/ZnO pouch full battery exhibit a high capacity retention of 86.9% after 100 cycles at 1 C. Notably, the measured heat generation rate is suppressed, somewhat enhancing systemic thermal safety. This work provides crucial experimental and theoretical guidance for the scalable application of high-performance and thermally safe Si-based anodes.

Mitigating the severe volume expansion of silicon (Si) anodes and developing scalable, low-cost fabrication processes are critical for commercializing high-energy-density batteries. Herein, ZnO-modified microspherical composite anode (F-Gr@Si/C/ZnO) using commercial Si powder and flaky graphite as raw materials has been constructed. The synthesis integrates efficient sand-milling pretreatment with spray drying and sintering. This rational design leverages spray drying to uniformly coat PVP and zinc acetate onto the Si/graphite surfaces. During subsequent annealing, PVP undergoes in-situ carbonization while zinc acetate decomposes into ZnO nanoparticles, jointly forming a highly uniform composite protective layer. The resulting F-Gr@Si/C/ZnO composite delivers exceptional electrochemical performance, retaining 717 mAh g-1 after 1000 cycles at 1 A g-1 (91.6% retention). Even at a high rate of 2 A g-1, a capacity of 502.6 mAh g-1 is preserved over 1000 cycles. Furthermore, LCO||F-Gr@Si/C/ZnO pouch full battery exhibit a high capacity retention of 86.9% after 100 cycles at 1 C. Notably, the measured heat generation rate is suppressed, somewhat enhancing systemic thermal safety. This work provides crucial experimental and theoretical guidance for the scalable application of high-performance and thermally safe Si-based anodes.

Exploring sodium-ion layered oxides with broad compositional diversity is an important approach for the development of high-performance positive electrodes. Structural chemistry determined by composition plays a decisive role in performance improvement, but the relationship between composition and structure becomes more elusive in complex multi-component systems. Here we propose an electronegativity entropy weight concept to understand entropy-dominated phases formation. Electronegativity and configurational entropy are used to quantify key interactions in layered materials. Guided by this understanding, we design a sodium-deficient layered oxide with an O3 stacking sequence. This material demonstrates good structural and thermal stability, along with air stability (negligible performance degradation after air exposure), cycling stability (93.02% capacity retention after 200 cycles), and rate capability (retaining 69.1% capacity retention from 86.5 mA g⁻¹ to 1.73 A g⁻¹). Even in potassium-ion batteries with larger inserted ions, the material still exhibits cycling stability. This strategy provides valuable compositional guidance for the rational design of high-performance layered oxide materials.