CERAMICS INTERNATIONAL
·
2024
·Vol. 50
·期 14
·24995-25004
·
IF 5.1
Zhiyi Li,Haili Sun,Wei Wei,Fengxia Liu,Xiaofei Xu,Zhijun Liu
The emerging market of high-power lithium-ion batteries (LIBs) highlights the importance of developing high-voltage cathodes. Lithium nickel phosphate (LiNiPO 4 ) with the highest theoretical discharge potential (∼5.1V) has attracted increasing attention due to its stable olivine structure. In this study, ultrathin carbon layer-coated LiNiPO 4 was synthesized using oleylamine-assisted solvothermal method under different solvothermal times, and the effect of solvothermal time (1h–18h) on LiNiPO 4 samples is fully investigated. X-ray diffraction (XRD) shows that high-purity LiNiPO 4 materials can be prepared after calcination of the solvothermal product under N 2 , but adding part of H 2 to the calcination atmosphere will lead to the generation of impurities in the target product. As the solvothermal time increases, the product will agglomerate and grow, the particle size will increase, and the morphology will change from nanoparticle to rodlike structure. After the high-temperature calcination step, the oleylamine is completely carbonized, and a conductive carbon layer is successfully coated on the LiNiPO 4 with the thickness of 2 nm. As the solvothermal time increases, the graphitization degree of oleylamine increases after carbonization. The existence of the carbon layer and the increase in the degree of graphitization are beneficial to improving the electrical conductivity and Li-ion diffusion rate of LiNiPO 4 . The initial discharge capacity of LNP@C-12h product prepared with 12 h solvothermal time is 35 mA h g −1 at 0.1 C. Rietveld analysis shows that the anti-site defect concentration of the LNP@C material is 1.07 %, and the proportion increases to 2.83 % after several cycles. This work provides a positive contribution to the synthesis and modification of high-voltage LiNiPO 4 materials and explains the electrochemical performance degradation of LiNiPO 4 from the perspective of increasing the concentration of anti-site defects.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
锂离子电池
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
Shi Wang,Qingyuan Li,Minglei Bai,Jixin He,Chongyang Liu,Zengxi Li,Xiangfeng Liu,Wen-yong Lai,Liaoyun Zhang
Lithium-ion batteries (LIBs) using solid-state electrolytes (SSEs) can improve safety and energy density comparable with the liquid electrolytes (LE)-based counterparts. Especially, employing garnet-type SSEs to prepare solid-state LIBs are promising to achieve high-energy cells. However, the unbending and brittle issues of the inorganic SSE films are not suitable to fabricate flexible and stretchable energy storage devices. Here, We find that introducing specific polymer (30 wt%) into Li 6.75 La 3 Zr 1.75 Ta 0.25 O 12 (LLZTO) can strongly increase the strength of the composite polymer-in-inorganic electrolyte (CIE) film. Both in-situ and ex-situ characterizations demonstrate that CIE delivers an excellent ability to suppress the growth of Li dendrites due to the close packing of LLZTO and effective filled grain boundaries and voids inside the CIE film by the polymer. The CIE inherits impressive electrochemical performance from LLZTO. As a result, the assembled LiFePO 4 (LFP)/CIE/Li cell delivers better cell performance than LFP/LE-separator/Li cell at ambient temperature (AT). The assembled high-voltage cathode (Li 1.2 Mn 0.6 Ni 0.2 O 2 , 4.8 V)/CIE/Li cell also displays an excellent cell performance at AT. The present study offers new insights into exploring of flexible polymer-in-ceramic electrolytes for high-voltage LIBs with improved safety and energy density .
研究领域:
材料科学
·
电化学
·
能源存储
·
固态电池
·
纳米复合材料
·
界面工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Wei Feng,Huirong Liu,Mingliang Zhao,Jianling Li,Feiyu Kang
The poly(ethylene oxide) based composite solid electrolyte(PEO-CSE) is an effective solution for developing high-performance solid-state lithium battery . However, the poly(ethlene oxide)(PEO) based solid-state lithium battery using 4.0 V cathode suffers from severe interfacial instability problems. In this work, we add additive lithium difluorophosphate(LiPO 2 F 2 ) into the PEO-CSE to form a stable and low resistance interphase at the cathode/electrolyte interface during charge/discharge process. The electrochemical stability window of PEO-CSE increases to ∼5.0 V. Besides, the electrochemical performance of PEO based solid-state lithium battery with LiCoO 2 as cathode is excellent. The discharge capacity of LiCoO 2 /Li cell with LiPO 2 F 2 reaches 108.5 mAh g −1 at 1.0C. In contrast, the discharge capacity that without LiPO 2 F 2 is only 60.0 mAh g −1 . Meanwhile, the PEO-CSE with LiPO 2 F 2 cell delivers stable cycle performance at 4.2 V. The capacity retention maintains 88.5% compared with 16.1%(without LiPO 2 F 2 ) after 100 cycles. Furthermore, it's still maintains 83.3% after 150 cycles. In addition, the cathode/electrolyte interface is analyzed by transmission electron microscope(TEM) and X-ray photoelectron spectroscopy(XPS). Galvanostatic intermittent titration test(GITT) is used to analyze the dynamic diffusion performance. This strategy provides a simple and effective way to improve the high voltage stability of the cathode/electrolyte interface.
研究领域:
电化学
·
材料科学
·
能源存储
·
固态电池
·
界面工程
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 39
·2302691
·
IF 13.3
Jing Yu,Guodong Zhou,Yueqing Li,Yuhao Wang,Dengjie Chen,Francesco Ciucci
Composite polymer-ceramic electrolytes have shown considerable potential for high-energy-density Li-metal batteries as they combine the benefits of both polymers and ceramics. However, low ionic conductivity and poor contact with electrodes limit their practical usage. In this study, a highly conductive and stable composite electrolyte with a high ceramic loading is developed for high-energy-density Li-metal batteries. The electrolyte, produced through in situ polymerization and composed of a polymer called poly-1,3-dioxolane in a poly(vinylidene fluoride)/ceramic matrix, exhibits excellent room-temperature ionic conductivity of 1.2 mS cm −1 and high stability with Li metal over 1500 h. When tested in a Li|electrolyte|LiFePO 4 battery, the electrolyte delivers excellent cycling performance and rate capability at room temperature, with a discharge capacity of 137 mAh g −1 over 500 cycles at 1 C. Furthermore, the electrolyte not only exhibits a high Li + transference number of 0.76 but also significantly lowers contact resistance (from 157.8 to 2.1 Ω) relative to electrodes. When used in a battery with a high-voltage LiNi 0.8 Mn 0.1 Co 0.1 O 2 cathode, a discharge capacity of 140 mAh g −1 is achieved. These results show the potential of composite polymer-ceramic electrolytes in room-temperature solid-state Li-metal batteries and provide a strategy for designing highly conductive polymer-in-ceramic electrolytes with electrode-compatible interfaces.
研究领域:
材料科学
·
电化学
·
能源存储
·
固态电池
·
高分子化学
·
无机非金属材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）