ChemSusChem
·
2023
·Vol. 16
·期 15
·e202300244
·
IF 8.4
Shuai Tong,Hui Pan,Hang Liu,Xiaoyu Zhang,Xiangyu Liu,Min Jia,Yahao Kang,Yong Yuan,Xinyi Du,Xiaohong Yan
Graphical The improvement of the energy density of Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) is now related to the utilization of the third Na + , which was reported to be electrochemically inaccessible. Our research revealed that Ti-doped Na 3 V 2 (PO 4 ) 2 F 3 (NVTPF) could be overcharged at approximately 4.9 V without forming the irreversible metastable phase, which means the electrochemical inactive Na + could be effectively attracted without affecting the subsequent electrochemical behavior. Polyanionic material, specifically the NASICON-type material, is considered a promising cathode material for Na-ion batteries (SIBs) because of its stable structure and high operating voltage. Further, it improves the energy density correlated with the well utilization of all Na in the compound. For Na 3 V 2 (PO 4 ) 2 F 3 (NVPF), the extraction of the third Na, reported as the electrochemical inactivated, can be realized at a high voltage region while forming an irreversible tetragonal phase. In this study, we introduce Ti doping to the Na 2 VTi(PO 4 ) 2 F 3 (NVTPF) material; we reveal that the Ti-doped NVTPF could effectively suppress the irreversible phase transformation, thus successfully harnessing Na in a wide voltage range. Experimental study discloses that the Ti-substituted Na 2 VTi(PO 4 ) 2 F 3 could take up the Na + from Amam phase to Cmc21 phase between 1.0 V and 4.8 V reversibly accounting for the 2 Na + transportation that shows favorable Na + kinetics and structural stability. Our research provides the strategy to stabilize the polyanion structure upon charging at a high voltage range and inspires the utilization of full sodium in the polyanionic materials, which could be considered as a material design for future conventional applications.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2025
·
IF 5.5
Ketai Ren,Jinkai Qiu,Honglai Liu,Hongfang Song,Quan Li,Jingkun Li
Fluorophosphate Na3V2(PO4)2F3 (NVPF) is considered a promising cathode material for sodium-ion batteries, while its specific capacity is still insufficient compared to that of cathodes of lithium-ion batteries. Activating the third Na+ effectively increases the specific capacity of NVPF. However, the accompanied irreversible phase transition deteriorates the cycling stability. In this study, we synthesized sodium-rich Na3.5V1.5Mg0.5(PO4)2F3 (NVMPF) through doping low-valence Mg2+ with a high content, which introduces an extra 0.5 Na+ in the crystal lattice. The extra 0.5 Na+ remains in the lattice of NVMPF, acting as “pillars” to suppress the irreversible phase transition after the third Na+ is extracted by activating the V5+/4+ redox couple at a high voltage. Thus, NVMPF achieves a specific discharge capacity of 170 mAh g–1 between 1.0 and 4.7 V while maintaining the tetragonal structure of NVMPF. This work offers insightful guidelines to achieve the full utilization of three Na+ with enhanced cycling stability.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2025
·
IF 19
Xuheng Jiang,Qinfeng Zheng,Shun Zheng,Zuojun Yang,Yixiao Zhang,Xi Liu,Liwei Chen
Li 2 MnO 3 , a cobalt- and nickel-free layered oxide material with high theoretical capacity, is a promising candidate for next-generation, cost-effective cathode materials in lithium-ion batteries. However, its practical application is hindered by severe irreversible phase transition from layered to spinel structure and oxygen loss, resulting in poor cycling performance. In this study, a high-entropy stabilized material, Li 1.0 Na 0.2 K 0.2 Mn 0.535 Zr 0.015 Cu 0.025 Mg 0.025 O 1.7 F 0.3 (HE-LMO), is developed to mitigate these issues. The high-entropy design effectively stabilizes the layered structure, suppresses the formation of Mn 3 O 4 , and reduces irreversible oxygen evolution. As a result, HE-LMO exhibits enhanced structural stability and delivers a specific capacity of ≈270 mAh g −1 after 20 cycles, attributed to the activation of reversible oxygen redox activity. Advanced characterization techniques, including X-ray absorption spectroscopy, in situ X-ray diffraction, and ex situ aberration-corrected scanning transmission electron microscopy, are employed to elucidate the impact of high-entropy stabilization on the material's performance. These findings highlight the effectiveness of high-entropy stabilization in improving lithium-rich manganese-based cathode materials, providing a novel strategy for developing low-cost, high-performance cathode materials for lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机固体化学
·
先进电池技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Shuang Liu,Lianyi Shao,Xuejing Zhang,Meng Zhou,Zhanliang Tao,Jun Chen
KTiOPO 4 (KTP) microblocks, which were prepared using a simple solid state method, have been used as novel anode materials for sodium ion batteries (SIBs). The as-prepared KTP microblocks with size distribution of 300–500 nm delivered high performance of electrochemical storage of sodium, such as an initial charge capacity of 108.7 mAh g −1 at 200 mA g −1 with almost no capacity loss in 1000 cycles, and good rate capability of 80.3 mAh g −1 even at the current density of 1000 mA g −1 . Ex situ XPS and in situ XRD showed an irreversible phase reaction mechanism during the insertion/extraction of Na + . Dendrite formation at lower potential could be suppressed at the average potential of 1.3 V. This work indicated that KTP microblocks are low-cost and safe anode materials for SIBs.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-11
·
IF 17.694
Zhang Danfeng,Liu Ming,Ma Jiabin,Yang Ke,Chen Zhen,Li Kaikai,Zhang Chen,Wei Yinping,Zhou Min,Wang Peng,He Yuanbiao,Lv Wei,Yang Quan-Hong,Kang Feiyu,He Yan-Bing
High-voltage lithium metal batteries suffer from poor cycling stability caused by the detrimental effect on the cathode of the water moisture present in the non-aqueous liquid electrolyte solution, especially at high operating temperatures (e.g., ≥60 °C). To circumvent this issue, here we report lithium hexamethyldisilazide (LiHMDS) as an electrolyte additive. We demonstrate that the addition of a 0.6 wt% of LiHMDS in a typical fluorine-containing carbonate-based non-aqueous electrolyte solution enables a stable Li||LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) coin cell operation up to 1000 or 500 cycles applying a high cut-off cell voltage of 4.5 V in the 25 °C−60 °C temperature range. The LiHMDS acts as a scavenger for hydrofluoric acid and water and facilitates the formation of an (electro)chemical robust cathode|electrolyte interphase (CEI). The LiHMDS-derived CEI prevents the Ni dissolution of NCM811, mitigates the irreversible phase transformation from layered structure to rock-salt phase and suppresses the side reactions with the electrolyte solution.
研究领域:
电化学
·
材料科学
·
电池技术
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）