Carbon was coated on the surface of LiMnSiOto improve the electrochemical performance as cathode materials, which were synthesized by the solution method followed by heat treatment at 700 ℃ and the solid-state method...Carbon was coated on the surface of LiMnSiOto improve the electrochemical performance as cathode materials, which were synthesized by the solution method followed by heat treatment at 700 ℃ and the solid-state method followed by heat treatment at 950 ℃. It is shown that the cycling performance is greatly enhanced by carbon coating, compared with the pristine LiMnSiOcathode obtained by the solution method. The initial discharge capacity of LiMnSiO/C nanocomposite is 280.9 m Ah/g at 0.05 C with the carbon content of 33.3 wt%. The reasons for the improved electrochemical performance are smaller grain size and higher electronic conductivity due to the carbon coating. The LiMnSiO/C cathode material obtained by the solid-state method exhibits poor cycling performance, the initial discharge capacity is less than 25 m Ah/g.展开更多
针对AZ31镁合金作为镁电池负极时存在自腐蚀速率大、阳极极化、电位滞后等问题,寻找合适的缓蚀剂及其用量调配电解液以提高电池的放电性能。通过腐蚀浸泡试验表征了缓蚀剂Li_(2)CrO_(4)的缓蚀效果,然后通过极化曲线、电化学阻抗谱研究了...针对AZ31镁合金作为镁电池负极时存在自腐蚀速率大、阳极极化、电位滞后等问题,寻找合适的缓蚀剂及其用量调配电解液以提高电池的放电性能。通过腐蚀浸泡试验表征了缓蚀剂Li_(2)CrO_(4)的缓蚀效果,然后通过极化曲线、电化学阻抗谱研究了Mg(ClO_(4))_(2)溶液中Li_(2)CrO_(4)用量对AZ31镁合金电化学性能的影响,最后通过组装水系镁锰电池进行恒流放电作为应用端测试。结果表明:Li_(2)CrO_(4)能够使AZ31镁合金的腐蚀电位正移,最大正移量达到150 m V,在水系镁锰电池应用中能够提高镁电池的放电平台,当Li_(2)CrO_(4)质量分数为0.7%时放电平台提高0.15 V左右;当Li_(2)CrO_(4)质量分数为1.2%时,其能够显著改善AZ31镁合金在Mg(ClO_(4))_(2)溶液中的腐蚀,水系镁锰电池放电容量达最大,为196.9 m A·h,相对空白溶液,电池的放电容量提高约64%,工作电压高达1.39 V且放电曲线稳定。展开更多
Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),of much interest owing to its high ionic conductivity,superior air stability,and low cost,has been regarded as one of the most promising solid-state electrolytes for next-gen...Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),of much interest owing to its high ionic conductivity,superior air stability,and low cost,has been regarded as one of the most promising solid-state electrolytes for next-generation solid-state lithium batteries(SSLBs).Unfortunately,the commercialization of SSLBs is still impeded by severe interfacial issues,such as high interfacial impedance and poor chemical stability.Herein,we proposed a simple and convenient in-situ approach to constructing a tight and robust interface between the Li anode and LATP electrolyte via a SnO_(2)gradient buffer layer.It is firmly attached to the surface of LATP pellets due to the volume expansion of SnO_(2)when in-situ reacting with Li metal,and thus effectively alleviates the physical contact loosening during cycling,as confirmed by the mitigated impedance rising.Meanwhile,the as-formed SnO_(2)/Sn/LixSn gradient buffer layer with low electronic conductivity successfully protects the LATP electrolyte surface from erosion by the Li metal anode.Additionally,the LixSn alloy formed at the Li surface can effectively regulate uniform lithium deposition and suppress Li dendrite growth.Therefore,this work paves a new way to simultaneously address the chemical instability and poor physical contact of LATP with Li metal in developing low-cost and highly stable SSLBs.展开更多
以五氧化二钒干凝胶、碳酸锰、磷酸二氢铵、碳酸锂、乙炔黑为原料,采用固相法在相对较低的温度条件下合成了x Li Mn PO4·y Li3V2(PO4)3锂离子电池复合正极材料。采用X射线衍射(XRD)、扫描电镜(SEM)对其晶体结构和表面形貌进行表征...以五氧化二钒干凝胶、碳酸锰、磷酸二氢铵、碳酸锂、乙炔黑为原料,采用固相法在相对较低的温度条件下合成了x Li Mn PO4·y Li3V2(PO4)3锂离子电池复合正极材料。采用X射线衍射(XRD)、扫描电镜(SEM)对其晶体结构和表面形貌进行表征。结果表明,750℃下烧结15 h合成的3Li Mn PO4·Li3V2(PO4)3为结晶良好的两相结构,颗粒粒径较小且分布比较均匀,其在室温、0.2 C倍率下首次充放电容量分别为144.8 m Ah/g和139.8 m Ah/g,循环50次后容量为130.5 m Ah/g。展开更多
基金Funded by the National Natural Science Foundation of China(No.51372136)Shenzhen Basic Research Project(No.CYJ20130402145002372)
文摘Carbon was coated on the surface of LiMnSiOto improve the electrochemical performance as cathode materials, which were synthesized by the solution method followed by heat treatment at 700 ℃ and the solid-state method followed by heat treatment at 950 ℃. It is shown that the cycling performance is greatly enhanced by carbon coating, compared with the pristine LiMnSiOcathode obtained by the solution method. The initial discharge capacity of LiMnSiO/C nanocomposite is 280.9 m Ah/g at 0.05 C with the carbon content of 33.3 wt%. The reasons for the improved electrochemical performance are smaller grain size and higher electronic conductivity due to the carbon coating. The LiMnSiO/C cathode material obtained by the solid-state method exhibits poor cycling performance, the initial discharge capacity is less than 25 m Ah/g.
文摘针对AZ31镁合金作为镁电池负极时存在自腐蚀速率大、阳极极化、电位滞后等问题,寻找合适的缓蚀剂及其用量调配电解液以提高电池的放电性能。通过腐蚀浸泡试验表征了缓蚀剂Li_(2)CrO_(4)的缓蚀效果,然后通过极化曲线、电化学阻抗谱研究了Mg(ClO_(4))_(2)溶液中Li_(2)CrO_(4)用量对AZ31镁合金电化学性能的影响,最后通过组装水系镁锰电池进行恒流放电作为应用端测试。结果表明:Li_(2)CrO_(4)能够使AZ31镁合金的腐蚀电位正移,最大正移量达到150 m V,在水系镁锰电池应用中能够提高镁电池的放电平台,当Li_(2)CrO_(4)质量分数为0.7%时放电平台提高0.15 V左右;当Li_(2)CrO_(4)质量分数为1.2%时,其能够显著改善AZ31镁合金在Mg(ClO_(4))_(2)溶液中的腐蚀,水系镁锰电池放电容量达最大,为196.9 m A·h,相对空白溶液,电池的放电容量提高约64%,工作电压高达1.39 V且放电曲线稳定。
基金financially supported by the China Postdoctoral Science Foundation(2021M700396)the National Natural Science Foundation of China(52102206)the research grants from the National Research Foundation(2022K1A3A1A20014496 and 2022R1F1A1074707)funded by the government of the Republic of Korea。
文摘Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),of much interest owing to its high ionic conductivity,superior air stability,and low cost,has been regarded as one of the most promising solid-state electrolytes for next-generation solid-state lithium batteries(SSLBs).Unfortunately,the commercialization of SSLBs is still impeded by severe interfacial issues,such as high interfacial impedance and poor chemical stability.Herein,we proposed a simple and convenient in-situ approach to constructing a tight and robust interface between the Li anode and LATP electrolyte via a SnO_(2)gradient buffer layer.It is firmly attached to the surface of LATP pellets due to the volume expansion of SnO_(2)when in-situ reacting with Li metal,and thus effectively alleviates the physical contact loosening during cycling,as confirmed by the mitigated impedance rising.Meanwhile,the as-formed SnO_(2)/Sn/LixSn gradient buffer layer with low electronic conductivity successfully protects the LATP electrolyte surface from erosion by the Li metal anode.Additionally,the LixSn alloy formed at the Li surface can effectively regulate uniform lithium deposition and suppress Li dendrite growth.Therefore,this work paves a new way to simultaneously address the chemical instability and poor physical contact of LATP with Li metal in developing low-cost and highly stable SSLBs.
文摘以五氧化二钒干凝胶、碳酸锰、磷酸二氢铵、碳酸锂、乙炔黑为原料,采用固相法在相对较低的温度条件下合成了x Li Mn PO4·y Li3V2(PO4)3锂离子电池复合正极材料。采用X射线衍射(XRD)、扫描电镜(SEM)对其晶体结构和表面形貌进行表征。结果表明,750℃下烧结15 h合成的3Li Mn PO4·Li3V2(PO4)3为结晶良好的两相结构,颗粒粒径较小且分布比较均匀,其在室温、0.2 C倍率下首次充放电容量分别为144.8 m Ah/g和139.8 m Ah/g,循环50次后容量为130.5 m Ah/g。
