The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as ...The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al_(2)O_(3)coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer.展开更多
ZnO with good lithiophilicity has widely been employed to modify the lithiophobic substrates and facilitate uniform lithium(Li)deposition.The overpotential of ZnO-derived Li anode during cycling depends on the lithiop...ZnO with good lithiophilicity has widely been employed to modify the lithiophobic substrates and facilitate uniform lithium(Li)deposition.The overpotential of ZnO-derived Li anode during cycling depends on the lithiophilicity of both LiZn and Li_(2)O products upon lithiation of ZnO.However,the striking differences in the lithiophilicity between Li_(2)O and LiZn would result in a high overpotential during cycling.In this research,the Al_(2)O_(3)/nZnO(n≥1)hybrid layers were precisely fabricated by atomic layer deposition(ALD)to regulate the lithiophilicity of ZnO phase and Li_(2)O/LiZn configuration—determining the actual Li loading amount and Li plating/stripping processes.Theoretically,the Li adsorption energy(E_(a))values of LiZn and Li_(2)O in the LiZn/Li_(2)O configuration are separately predicted as-2.789 and-3.447 eV.In comparison,the E_(a) values of LiZn,LiAlO_(2),and Li_(2)O in the LiZn/LiAlO_(2)/Li_(2)O configuration upon lithiation of Al_(2)O_(3)/8ZnO layer are calculated as-2.899,-3.089,and-3.208 eV,respectively.Importantly,a novel introduction of LiAlO_(2)into the LiZn/Li_(2)O configuration could enable the hierarchical Li plating/stripping and reduce the overpotentials during cycling.Consequently,the Al_(2)O_(3)/8ZnO-derived hybrid Li-metal anode could exhibit electrochemical performances superior to these of ZnO-derived Li anode in both symmetrical and full cells paired with a LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)cathode.展开更多
LiNi1-xCoxO2 with x=0.1, 0.2, 0.3, 0.5 and 1 were prepared by co-precipitation of mixed solution of Ni- and Co-salt in NaOH. The structure of LiNi1-xCoxO2 was analyzed by XRD. The results show that the unit cell const...LiNi1-xCoxO2 with x=0.1, 0.2, 0.3, 0.5 and 1 were prepared by co-precipitation of mixed solution of Ni- and Co-salt in NaOH. The structure of LiNi1-xCoxO2 was analyzed by XRD. The results show that the unit cell constants a and c decrease as the Co content increases. Although the change of unit cell constants can reflect the substitution of Co ions with Ni ions in the lab, the splits of the pairs of (006), (102) and (108), (110) in the XRD pattern can not reflect the presence of Ni2+ in the lithium site.展开更多
利用超细旋转盘式砂磨机细化颗粒固相烧结法,合成锂离子电池正极材料Li Ni0.80Co0.15Al0.05O2。原料经过砂磨后,混合均匀,粒径达到纳米级。根据塔曼定理,混合均匀的微小粒径可以在相同的烧结温度下,提高烧结的强度。SEM、XRD分别表征NC...利用超细旋转盘式砂磨机细化颗粒固相烧结法,合成锂离子电池正极材料Li Ni0.80Co0.15Al0.05O2。原料经过砂磨后,混合均匀,粒径达到纳米级。根据塔曼定理,混合均匀的微小粒径可以在相同的烧结温度下,提高烧结的强度。SEM、XRD分别表征NCA材料的颗粒形貌和晶形结构。结果显示,通过细化颗粒烧结后的样品具有良好的形貌和层状结构。CV法测试样品的氧化还原性能,电池测试系统测试样品的电化学性能。测试结果显示,经过细化颗粒,在720℃合成的NCA材料具有良好的层状结构,018/110峰分裂明显。样品的电化学性能优良,0.2C下,首次放电容量达到182 m Ah?g?1,30次循环后容量保持率99.9%。1C下,首次放电容量153 m Ah?g?1,100次循环后容量保持率92.6%。展开更多
基金the financial support from the 261Project of MIIT and Natural Science Foundation of Jiangsu Province(No.BK20240179)。
文摘The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al_(2)O_(3)coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer.
基金supported by the National Key Research and Development Program of China(2021YFB2400202)the National Natural Science Foundation of China(52104313)+1 种基金the Key Research and Development Plan of Shaanxi(2024GH-YBXM-11)the Foshan Science and Technology Innovation Team Project(1920001004098).
文摘ZnO with good lithiophilicity has widely been employed to modify the lithiophobic substrates and facilitate uniform lithium(Li)deposition.The overpotential of ZnO-derived Li anode during cycling depends on the lithiophilicity of both LiZn and Li_(2)O products upon lithiation of ZnO.However,the striking differences in the lithiophilicity between Li_(2)O and LiZn would result in a high overpotential during cycling.In this research,the Al_(2)O_(3)/nZnO(n≥1)hybrid layers were precisely fabricated by atomic layer deposition(ALD)to regulate the lithiophilicity of ZnO phase and Li_(2)O/LiZn configuration—determining the actual Li loading amount and Li plating/stripping processes.Theoretically,the Li adsorption energy(E_(a))values of LiZn and Li_(2)O in the LiZn/Li_(2)O configuration are separately predicted as-2.789 and-3.447 eV.In comparison,the E_(a) values of LiZn,LiAlO_(2),and Li_(2)O in the LiZn/LiAlO_(2)/Li_(2)O configuration upon lithiation of Al_(2)O_(3)/8ZnO layer are calculated as-2.899,-3.089,and-3.208 eV,respectively.Importantly,a novel introduction of LiAlO_(2)into the LiZn/Li_(2)O configuration could enable the hierarchical Li plating/stripping and reduce the overpotentials during cycling.Consequently,the Al_(2)O_(3)/8ZnO-derived hybrid Li-metal anode could exhibit electrochemical performances superior to these of ZnO-derived Li anode in both symmetrical and full cells paired with a LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622)cathode.
文摘LiNi1-xCoxO2 with x=0.1, 0.2, 0.3, 0.5 and 1 were prepared by co-precipitation of mixed solution of Ni- and Co-salt in NaOH. The structure of LiNi1-xCoxO2 was analyzed by XRD. The results show that the unit cell constants a and c decrease as the Co content increases. Although the change of unit cell constants can reflect the substitution of Co ions with Ni ions in the lab, the splits of the pairs of (006), (102) and (108), (110) in the XRD pattern can not reflect the presence of Ni2+ in the lithium site.
文摘利用超细旋转盘式砂磨机细化颗粒固相烧结法,合成锂离子电池正极材料Li Ni0.80Co0.15Al0.05O2。原料经过砂磨后,混合均匀,粒径达到纳米级。根据塔曼定理,混合均匀的微小粒径可以在相同的烧结温度下,提高烧结的强度。SEM、XRD分别表征NCA材料的颗粒形貌和晶形结构。结果显示,通过细化颗粒烧结后的样品具有良好的形貌和层状结构。CV法测试样品的氧化还原性能,电池测试系统测试样品的电化学性能。测试结果显示,经过细化颗粒,在720℃合成的NCA材料具有良好的层状结构,018/110峰分裂明显。样品的电化学性能优良,0.2C下,首次放电容量达到182 m Ah?g?1,30次循环后容量保持率99.9%。1C下,首次放电容量153 m Ah?g?1,100次循环后容量保持率92.6%。
