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1.
Small ; : e2311197, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38593375

RESUMEN

Biomass-derived porous carbon materials are meaningful to employ as a hard carbon precursor for anode materials of sodium-ion batteries (SIBs) from a sustainability perspective. Here, a straightforward approach is proposed to develop rich closed pores in pinenut-derived carbon, with the aim of improving Na+ plateau storage by adjusting the pyrolysis temperature. The optimized sample, namely the pinenut-derived carbon at 1300 °C, demonstrates remarkable reversible specific capacity of 278 mAh g-1, along with a high initial Coulomb efficiency of 85% and robust cycling stability (with a capacity retention of 89% after 800 cycles at 0.2 A g-1). In situ and ex situ analyses unveil that the developed closed pores play a significant role in enhancing the plateau capacity, providing compelling evidence for the "adsorption-filling" mechanism. Moreover, the corresponding full-cell achieves a high energy density of 245.7 Wh kg-1 (based on the total weight of both electrode active materials) and exhibits outstanding rate capability (191.4 mAh g-1 at 3 A g-1).

2.
Fa Yi Xue Za Zhi ; 40(2): 154-163, 2024 Apr 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-38847030

RESUMEN

OBJECTIVES: To develop a deep learning model for automated age estimation based on 3D CT reconstructed images of Han population in western China, and evaluate its feasibility and reliability. METHODS: The retrospective pelvic CT imaging data of 1 200 samples (600 males and 600 females) aged 20.0 to 80.0 years in western China were collected and reconstructed into 3D virtual bone models. The images of the ischial tuberosity feature region were extracted to create sex-specific and left/right site-specific sample libraries. Using the ResNet34 model, 500 samples of different sexes were randomly selected as training and verification set, the remaining samples were used as testing set. Initialization and transfer learning were used to train images that distinguish sex and left/right site. Mean absolute error (MAE) and root mean square error (RMSE) were used as primary indicators to evaluate the model. RESULTS: Prediction results varied between sexes, with bilateral models outperformed left/right unilateral ones, and transfer learning models showed superior performance over initial models. In the prediction results of bilateral transfer learning models, the male MAE was 7.74 years and RMSE was 9.73 years, the female MAE was 6.27 years and RMSE was 7.82 years, and the mixed sexes MAE was 6.64 years and RMSE was 8.43 years. CONCLUSIONS: The skeletal age estimation model, utilizing ischial tuberosity images of Han population in western China and employing the ResNet34 combined with transfer learning, can effectively estimate adult ischium age.


Asunto(s)
Determinación de la Edad por el Esqueleto , Aprendizaje Profundo , Imagenología Tridimensional , Isquion , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Isquion/diagnóstico por imagen , Adulto , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Imagenología Tridimensional/métodos , China , Estudios Retrospectivos , Determinación de la Edad por el Esqueleto/métodos , Anciano , Adulto Joven , Anciano de 80 o más Años , Reproducibilidad de los Resultados
3.
Small ; 19(48): e2303151, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37605323

RESUMEN

Non-alkaline zinc-air batteries (ZABs) that use reversible O2 /ZnO2 chemistry exhibit excellent stability and superior reversibility compared to conventional alkaline ZABs. Unlike alkaline ZABs, ZnO2 discharge products are generated on the surface of the air cathodes in non-alkaline ZABs, requiring more gas-liquid-solid three-phase reaction interfaces. However, the kinetics of reported ZABs based on carbon black (CB) is far from satisfactory due to the insufficient reaction areas. The rational structural design of the air cathode is an effective way to increase active surfaces to further enhance the performance of non-alkaline ZABs. In this study, multi-walled carbon nanotubes (MW-CNTs) with unique mesoporous structures and high pore volumes are selected to replace CB in the air cathode preparation. Due to the larger electrochemically active surface area, superior hydrophobicity, and uniform electroconductibility of MW-CNTs-based cathodes, primary ZABs exhibit high specific capacity (704 mAh gZn-1 ) with a Zn utilization ratio of 85.85% at 1.0 mA cm-2 , excellent discharge rate performance, and negligible self-discharge. Furthermore, rechargeable ZABs also demonstrate outstanding rate capability and excellent cycling stability at various current densities. This work provides a fundamental understanding of the criteria for the cathode design of non-alkaline ZABs, thus opening a new pathway for more sustainable ZABs.

4.
Fa Yi Xue Za Zhi ; 39(1): 27-33, 2023 Feb 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-37038852

RESUMEN

OBJECTIVES: To examine the reliability and accuracy of Walker's model for estimating the sex of Han adults in western China by using cranium three-dimensional (3D) CT reconstruction, and to study the suitable cranial sex estimation model for Han people in western China. METHODS: A total of 576 cranial CT 3D reconstructed images from Hanzhong Hospital in Shaanxi Province from 2017 to 2021 were collected. These images were divided into the experimental group with 486 samples and the validation group with 90 samples. Walker's model was used by observer 1 to estimate the sex of experimental group samples. The logistic function applicable to Han people in western China was corrected by observer 1. The 90 samples in the validation group were scored and substituted into the modified logistic function to complete the back substitution test by observer 1, 2 and 3. RESULTS: The accuracy of sex estimation of Han adults in western China was 63.2%-77.2% by applying Walker's model. The accuracy of modified logistic function was 82.9%. The accuracy of sex estimation through back substitution test by 3 observers was 75.6%-91.1%, with a Kappa value of 0.689 (P<0.05) for inter-observer consistency and 0.874 (P<0.05) for intra-observer consistency. CONCLUSIONS: There are great differences in bone characteristics among people from different regions. The modified logistic function can achieve higher accuracy in Han adults in western China.


Asunto(s)
Determinación del Sexo por el Esqueleto , Humanos , Adulto , Reproducibilidad de los Resultados , Determinación del Sexo por el Esqueleto/métodos , Antropología Forense , Cráneo/diagnóstico por imagen , Cráneo/anatomía & histología , Imagenología Tridimensional , China , Tomografía Computarizada por Rayos X
5.
Fa Yi Xue Za Zhi ; 39(2): 129-136, 2023 Apr 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-37277375

RESUMEN

OBJECTIVES: To investigate the reliability and accuracy of deep learning technology in automatic sex estimation using the 3D reconstructed images of the computed tomography (CT) from the Chinese Han population. METHODS: The pelvic CT images of 700 individuals (350 males and 350 females) of the Chinese Han population aged 20 to 85 years were collected and reconstructed into 3D virtual skeletal models. The feature region images of the medial aspect of the ischiopubic ramus (MIPR) were intercepted. The Inception v4 was adopted as the image recognition model, and two methods of initial learning and transfer learning were used for training. Eighty percent of the individuals' images were randomly selected as the training and validation dataset, and the remaining were used as the test dataset. The left and right sides of the MIPR images were trained separately and combinedly. Subsequently, the models' performance was evaluated by overall accuracy, female accuracy, male accuracy, etc. RESULTS: When both sides of the MIPR images were trained separately with initial learning, the overall accuracy of the right model was 95.7%, the female accuracy and male accuracy were both 95.7%; the overall accuracy of the left model was 92.1%, the female accuracy was 88.6% and the male accuracy was 95.7%. When the left and right MIPR images were combined to train with initial learning, the overall accuracy of the model was 94.6%, the female accuracy was 92.1% and the male accuracy was 97.1%. When the left and right MIPR images were combined to train with transfer learning, the model achieved an overall accuracy of 95.7%, and the female and male accuracies were both 95.7%. CONCLUSIONS: The use of deep learning model of Inception v4 and transfer learning algorithm to construct a sex estimation model for pelvic MIPR images of Chinese Han population has high accuracy and well generalizability in human remains, which can effectively estimate the sex in adults.


Asunto(s)
Aprendizaje Profundo , Adulto , Femenino , Humanos , Masculino , Imagenología Tridimensional , Pelvis , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X , Adulto Joven , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años
6.
Angew Chem Int Ed Engl ; 62(30): e202304036, 2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37231580

RESUMEN

P-type organic electrode materials are known for their high redox voltages and fast kinetics. However, single-electron p-type organic materials generally exhibit low capacity despite high operating voltage and stability, while some multi-electron p-type organic materials have high theoretical capacity but low stability. To address this challenge, we explore the possibility of combining single-electron and multi-electron units to create high-capacity and stable p-type organic electrodes. We demonstrate the design of a new molecule, 4,4'-(10H-phenothiazine-3,7-diyl) bis (N,N-diphenylaniline) (PTZAN), which is created by coupling the triphenylamine molecule and the phenothiazine molecule. The resulting PTZAN||Zn battery shows excellent stability (2000 cycles), high voltage (1.3 V), high capacity (145 mAh g-1 ), and energy density of 187.2 Wh kg-1 . Theoretical calculations and in/ex situ analysis reveal that the charge storage of the PTZAN electrode is mainly driven by the redox of phenothiazine heterocycles and triphenylamine unit, accompanied by the combination/release of anions and Zn2+ .

7.
Small ; 18(45): e2204830, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36161496

RESUMEN

Sodium-ion batteries (SIBs) have attracted wide interest for energy storage because of the sufficient sodium element reserve on the earth; however, the electrochemical performance of SIBs cannot achieve the requirements so far, especially, the limitation of cathode materials. Here, a kilogram-scale route to synthesize Na2 FePO4 F/carbon/multi-walled carbon nanotubes microspheres (NFPF@C@MCNTs) composite with a high tap density of 1.2 g cm-3 is reported. The NFPF@C@MCNTs cathode exhibits a reversible specific capacity of 118.4 mAh g-1 at 0.1 C. Even under 5 C with high mass loading (10 mg cm-2 ), the specific capacity still maintains at 56.4 mAh g-1 with a capacity retention rate of 97% after 700 cycles. In addition, a hard carbon||NFPF@C@MCNTs pouch cell is assembled and tested, which exhibits a volumetric energy density of 325 Wh L-1 and gravimetrical energy density of 210 Wh kg-1 (base on electrode massing), and it provides more than 200 cycles with a capacity retention rate of 92%. Furthermore, the pouch cell can operate in an all-climate environment ranging from -40 to 80 °C. These results demonstrate that the NFPF@C@MCNTs microspheres are a promising candidate cathode for SIBs and facilitate its practical application in sodium cells.


Asunto(s)
Nanotubos de Carbono , Sodio , Hierro , Electrodos , Fluoruros
8.
Angew Chem Int Ed Engl ; 61(13): e202116930, 2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35044037

RESUMEN

Sodium-ion batteries (SIBs), as one of the potential candidates for grid-scale energy storage systems, are required to tackle extreme weather conditions. However, the all-weather SIBs with a wide operation-temperature range are rarely reported. Herein, we propose a wide-temperature range SIB, which involves a carbon-coated Na4 Fe3 (PO4 )2 P2 O7 (NFPP@C) cathode, a bismuth (Bi) anode, and a diglyme-based electrolyte. We demonstrate that solvated Na+ can be directly stored by the Bi anode via an alloying reaction without the de-solvent process. Furthermore, the NFPP@C cathode exhibits a high Na+ diffusion coefficient at low temperature. As a result, the Bi//NFPP@C battery exhibits perfect low-temperature behavior. Even at -70 °C, this battery still delivers 70.19 % of the room-temperature capacity. Furthermore, benefitting from the high boiling point of the electrolyte, this battery also works well at a high temperature of up to 100 °C. These results are encouraging for the further exploration of wide-temperature range SIBs.

9.
Angew Chem Int Ed Engl ; 61(47): e202211933, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36193861

RESUMEN

Lithium-sulfur (Li-S) batteries with high energy density are currently receiving enormous attention. However, their redox kinetics at low temperature is extremely tardy, and polysulfides shuttling is serious at high temperature, which severely hinders the implementation of wide-temperature Li-S batteries. Herein, we propose an all-climate Li-S battery based on an ether-based electrolyte by using a porous sub-nano aromatic framework (SAF) modified separator. It's demonstrated that the fully conjugated SAF-3 with a small pore size (0.97 nm) and narrow band gap (1.72 eV) could efficiently block the polysulfides shuttling at elevated temperature and boost the polysulfides conversion at low temperature. Consequently, the SAF-3 modified cells work well in a wide temperature ranging from -40 to 60 °C. Furthermore, when operated at room temperature, the modified cell exhibits 90 % capacity retention over 100 cycles under high-sulfur loading (5.0 mg cm-2 ) and lean electrolyte (5 µL mg-1 ).

10.
Angew Chem Int Ed Engl ; 61(36): e202208345, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-35833711

RESUMEN

Graphite anode suffers from great capacity loss and even fails to charge (i.e. Li+ -intercalation) under low temperature, mainly arising from the large overpotential including sluggish de-solvation process and insufficient ions movement in the solid electrolyte interphase (SEI). Herein, an electrolyte is developed by utilizing weakly solvated molecule ethyl trifluoroacetate and film-forming fluoroethylene carbonate to achieve smooth de-solvation and high ionic conductivity at low temperature. Evolution of SEI formed at different temperatures is further investigated to propose an effective room-temperature SEI formation strategy for low-temperature operations. The synergetic effect of tamed electrolyte and optimized SEI enables graphite with a reversible charge/discharge capacity of 183 mAh g-1 at -30 °C and fast-charging up to 6C-rate at room temperature. Moreover, graphite||LiFePO4 full cell maintains a capacity retention of 78 % at -30 °C, and 37 % even at a super-low temperature of -60 °C. This work offers a progressive insight towards fast-charging and low-temperature batteries.

11.
Angew Chem Int Ed Engl ; 61(32): e202206635, 2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-35610954

RESUMEN

Proton batteries are emerging in electrochemical energy storage because of the associated fast kinetics, low cost and high safety. However, their development is hindered by the relatively low energy density due to the limited choice of cathode materials. Herein, metal phosphate polyanion cathodes are proposed as the proton cathode for the first time. Combining experimental results and theoretical simulations, a universal criterion for the proton cathode was put forward. Vanadium fluorophosphate (VPO4 F) was demonstrated as a promising high-voltage proton cathode material with a specific capacity of 116 mAh g-1 at a high potential of 1.0 V (vs. SHE). The proton insertion/extraction mechanism in the VPO4 F electrode was also verified through X-ray diffraction (XRD) and photoelectron spectroscopy (XPS). Furthermore, the stability of VPO4 F was investigated in various electrolytes and the optimized electrolyte enabled the stable operation of VPO4 F for 300 cycles. This work provides new inspiration in the exploitation of new electrode materials for electrochemical proton storage devices.

12.
Int J Legal Med ; 135(3): 817-827, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33392655

RESUMEN

Seasonal or monthly databases of the diatom populations in specific bodies of water are needed to infer the drowning site of a drowned body. However, existing diatom testing methods are laborious, time-consuming, and costly and usually require specific expertise. In this study, we developed an artificial intelligence (AI)-based system as a substitute for manual morphological examination capable of identifying and classifying diatoms at the species level. Within two days, the system collected information on diatom profiles in the Huangpu and Suzhou Rivers of Shanghai, China. In an animal experiment, the similarities of diatom profiles between lung tissues and water samples were evaluated through a modified Jensen-Shannon (JS) divergence measure for drowning site inference, reaching a prediction accuracy of 92.31%. Considering its high efficiency and simplicity, our proposed method is believed to be more applicable than existing methods for seasonal or monthly water monitoring of diatom populations from sections of interconnected rivers, which would help police narrow the investigation scope to confirm the identity of an immersed body.


Asunto(s)
Bases de Datos Factuales , Diatomeas/clasificación , Ahogamiento/diagnóstico , Patologia Forense/métodos , Redes Neurales de la Computación , Animales , Inteligencia Artificial , China , Diatomeas/microbiología , Ahogamiento/microbiología , Pulmón/microbiología , Modelos Animales , Ratas , Ratas Sprague-Dawley , Ríos/microbiología , Estaciones del Año , Sensibilidad y Especificidad
13.
Int J Legal Med ; 135(6): 2409-2421, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34459973

RESUMEN

Deep learning based on radiological methods has attracted considerable attention in forensic anthropology because of its superior classification capacities over human experts. However, radiological instruments are limited in their nature of high cost and immobility. Here, we integrated a deep learning algorithm and three-dimensional (3D) surface scanning technique into a portable system for pelvic sex estimation. Briefly, the images of the ventral pubis (VP), dorsal pubis (DP), and greater sciatic notch (GSN) were cropped from virtual pelvic samples reconstructed from CT scans of 1000 individuals; 80% of them were used to train and internally evaluate convolutional neural networks (CNNs) that were then evaluated externally with the remaining samples. An additional 105 real pelvises were documented virtually with a handheld 3D surface scanner, and the corresponding snapshots of the VP, DP, and GSN were predicted by the trained CNN models. The CNN models achieved excellent performance in the external testing using CT-based images, with accuracies of 98.0%, 98.5%, and 94.0% for VP, DP, and GSN, respectively. When the CT-based models were applied to 3D scanning images, they obtained satisfactory accuracies above 95% on the VP and DP images compared to the GSN with 73.3%. In a single-blind trial, a multiple design that combined the three CNN models yielded a superior accuracy of 97.1% with 3D surface scanning images over two anthropologists. Our study demonstrates the great potential of deep learning and 3D surface scanning for rapid and accurate sex estimation of skeletal remains.


Asunto(s)
Aprendizaje Profundo , Imagenología Tridimensional/métodos , Redes Neurales de la Computación , Determinación del Sexo por el Esqueleto/métodos , Femenino , Humanos , Imagenología Tridimensional/instrumentación , Masculino , Pelvis/diagnóstico por imagen , Hueso Púbico/diagnóstico por imagen , Tomografía Computarizada por Rayos X
14.
Angew Chem Int Ed Engl ; 60(44): 23858-23862, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34463020

RESUMEN

The development of conventional rechargeable batteries based on intercalation chemistry in the fields of fast charge and low temperature is generally hindered by the sluggish cation-desolvation process at the electrolyte/electrode interphase. To address this issue, a novel desolvation-free sodium dual-ion battery (SDIB) has been proposed by using artificial graphite (AG) as anode and polytriphenylamine (PTPAn) as cathode. Combining the cation solvent co-intercalation and anion storage chemistry, such a SDIB operated with ether-based electrolyte can intrinsically eliminate the sluggish desolvation process. Hence, it can exhibit an extremely fast kinetics of 10 Ag-1 (corresponding to 100C-rate) with a high capacity retention of 45 %. Moreover, the desolvation-free mechanism endows the battery with 61 % of its room-temperature capacity at an ultra-low temperature of -70 °C. This advanced battery system will open a door for designing energy storage devices that require high power density and a wide operational temperature range.

16.
Small Methods ; : e2301745, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38326032

RESUMEN

Sodium-ion batteries (SIBs) have been regarded as promising candidates for large-scale energy storage system, and their electrochemical performance is determined by the cathode materials. Recently, the polyanion-type cathode Na4 Fe3 (PO4 )2 P2 O7 (NFPP) demonstrates decent performance, while there exists promotion space with respect to its cycle stability and rate capability. Herein, an entropy-enhanced Na4 Fe2.95 (NiCoMnMgZn)0.01 (PO4 )2 P2 O7 (HE-NFPP) cathode is proposed with improved rate performance (67.1 mAh g-1 at 50 C) and cycle performance (retention of 92.0% after 1000  cycles at 1 C). The enhancement of configuration entropy improves the structural stability of NFPP thermodynamically. In-situ XRD illustrates the sodium storage mechanism of HE-NFPP as an imperfect solid solution reaction driven by Fe2+ /Fe3+ redox with a low volume change of 4.0% (90.9% of NFPP). Through doping, the structure distortion and abrupt rearrangement are inhibited. Additionally, HE-NFPP and hard carbon (HC) are utilized to fabricate pouch cell that demonstrates an average working voltage of 3.0 V and a maximum energy density of 165 Wh kg-1 (based on the total mass of active materials). These results highlight the potential for enhancing the high-rate and long-cycle performance of NFPP as a promising cathode for SIBs through an entropy-enhanced multi-doping strategy.

17.
Clin Case Rep ; 11(5): e7374, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37215975

RESUMEN

Key Clinical Message: A 23-year-old male with a tumor in the eye socket was characterized by multimodal images, including ultrasonography, computed tomography, and magnetic resonance imaging. After admission, surgical resection of the tumor was performed and superficial angiomyxoma was confirmed. Two years later, this tumor recurred in the same location. Abstract: Superficial angiomyxoma (SAM) is a rare benign neoplasm composed mostly of myxoid material that can affect many parts of the body in middle-aged patients. Only a few case reports have involved imaging, which is extremely insufficient. Here, we present a case of SAM in the eye socket evaluated by imaging, including ultrasonography, computed tomography, and magnetic resonance imaging. The patient underwent surgical resection, and the diagnosis of SAM was confirmed. During the postoperative follow-up, the tumor recurred in the same location without metastasis 2 years later.

18.
Leg Med (Tokyo) ; 65: 102304, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37562072

RESUMEN

The method proposed by Suchey-Brooks for adult age estimation based on the surface morphology of the pubic symphysis has been widely accepted. The applicability of the method varies considerably in different populations. The present study established a virtual reference sample and aimed to develop population-specific criteria that can be used for age estimation in different skeletal samples. First, The dry bone specimens from 100 individuals were compared with their corresponding three-dimensional (3D) reconstruction model and showed high inter-method agreement (k = 0.743-0.811), suggesting that the virtual bone model and physical bone specimens have comparable performances in describing the surface morphology of the pubic symphysis. We retrospectively collected clinical computed tomography (CT) data from 895 Chinese patients to create a virtual reference sample of the pubic symphysis. Based on the original Suchey-Brooks method, each of the 895 reference samples was assigned a phase, for each sex and phase, data on the mean age, standard deviation, and 95% age range of the corresponding sample were obtained, which was then used as the "method modified for Chinese" (modified method) and compared to the "SB method". Compared to the SB method, modified method had a lower inaccuracy in dry bones for males over 35 years and females over 45 years, in dry bone CT test sample for males over 55 years and females over 45 years, and in postmortem CT test sample for males over 35 years and females over 55 years. The modified method can improve the accuracy of age estimation for older samples over 40 years. It has shown considerable reliability when applied as a population-specific criterion, but its accuracy is still not sufficient, and caution is needed when using it.


Asunto(s)
Pueblos del Este de Asia , Sínfisis Pubiana , Adulto , Femenino , Humanos , Masculino , Determinación de la Edad por el Esqueleto/métodos , Antropología Forense/métodos , Imagenología Tridimensional/métodos , Sínfisis Pubiana/anatomía & histología , Sínfisis Pubiana/diagnóstico por imagen , Reproducibilidad de los Resultados , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Persona de Mediana Edad
19.
J Colloid Interface Sci ; 640: 908-916, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36907150

RESUMEN

Lithium-sulfur (Li-S) batteries are featured with high gravimetric energy density, yet their commercial application is significantly deteriorated with the severe self-discharging resulted from the polysulfides shuttle and sluggish electrochemical kinetics. Here, a hierarchical porous carbon nanofibers implanted with Fe/Ni-N (denoted as Fe-Ni-HPCNF) catalytic sites are prepared and used as a kinetics booster toward anti-self-discharged Li-S batteries. In this design, the Fe-Ni-HPCNF possesses interconnected porous skeleton and abundant exposed active sites, enabling fast Li-ion conduction, excellent shuttle inhibition and catalytic ability for polysulfides' conversion. Combined with these advantages, this cell with the Fe-Ni-HPCNF equipped separator exhibits an ultralow self-discharged rate of 4.9% after resting for one week. Moreover, the modified batteries deliver a superior rate performance (783.3 mAh g-1 at 4.0 C) and an outstanding cycling life (over 700 cycles with 0.057% attenuation rate at 1.0 C). This work may guide the advanced design of anti-self-discharged Li-S batteries.

20.
Nat Commun ; 13(1): 6064, 2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36229436

RESUMEN

Nowadays, electrolytes for commercial batteries are mostly liquid solutions composed of solvent and salt to migrate the ions. However, solvents of the electrolyte bring several inherent limitations, either the electrochemical window, working temperature, volatility or flammability. Herein, we report polyphosphoric acid as a solvent-free protic liquid electrolyte, which excludes the demerits of solvent and exhibits unprecedented superiorities, including nonflammability, wider electrochemical stability window (>2.5 V) than aqueous electrolyte, low volatility and wide working temperature range (>400 °C). The proton conductive electrolyte enables MoO3/LiVPO4F rocking-chair battery to operate well in a wide temperature range from 0 °C to 250 °C and deliver a high power density of 4975 W kg-1 at a high temperature of 100 °C. The solvent-free electrolyte could provide a viable route for the stable and safe batteries working under harsh conditions, opening up a route towards designing wide-temperature electrolytes.

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