The side reaction between the active material and liquid-electrolyte cause structural damage and particle pulverization is one of the important factors leading to the capacity decay of LiNi0.80Co0.15Al0.05O2(NCA)mater...The side reaction between the active material and liquid-electrolyte cause structural damage and particle pulverization is one of the important factors leading to the capacity decay of LiNi0.80Co0.15Al0.05O2(NCA)materials in Li ion batteries(LIBs).Surface modification is an effective strategy for NCA cathodes,which could alleviate the degradation associated with surface processes.Herein,a surface structure rearrangement of NCA cathode secondary particles was reported by in-situ forming a solid electrolyte LiBO2.The LiBO2 is beneficial for alleviating the stress during charge/discharge process,thereby slowing down the rate of cracks formation in the secondary particles,which facilitates the Li+de-intercalation as well as prevents penetration of the liquid-electrolyte into the interior of the particles.As a result,the surface structure rearrangement NCA(RS-NCA)delivers a high discharge capacity of 202.5 m Ah g^-1 at 0.1 C,and exhibits excellent cycle stability with discharge capacity retaining 148 m Ah g^-1 after 200 cycles at 2 C.This surface structure rearrangement approach provides a new viewpoint in designing high-performance high-voltage LIBs.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
以Li_2CO_3为锂源,采用纳米砂磨辅助固相合成了纯相LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料,研究了Li_2CO_3加入方式对所得样品结构、形貌以及电化学性能的影响.结果表明,加锂方式基本不影响材料的形貌和尺寸,但对材料的微结构和性能...以Li_2CO_3为锂源,采用纳米砂磨辅助固相合成了纯相LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料,研究了Li_2CO_3加入方式对所得样品结构、形貌以及电化学性能的影响.结果表明,加锂方式基本不影响材料的形貌和尺寸,但对材料的微结构和性能有明显的影响.纳米砂磨一步混合所有原料烧结所得LiNi_(0.8)Co_(0.15)Al_(0.05)O_2样品的阳离子混排程度比后研磨加碳酸锂烧结所得LiNi_(0.8)Co_(0.15)Al_(0.05)O_2样品的要低,更利于锂离子的扩散,对应的样品具有更高的放电比容量和库伦效率,但循环性能没有太大的差别.纳米砂磨一步混合所有原料在800℃烧结得到的LiNi_(0.8)Co_(0.15)Al_(0.05)O_2样品,1C循环首次放电比容量可达170.9 m Ah/g,50次循环后容量保持率为92.6%.展开更多
基金the National Natural Science Foundation of China(51764048,51703118 and 51474191)Yunnan Province Thousand Youth Talents Plan+1 种基金the Application Basis Research Project of Yunnan Province Science and Technology Department(2017FD144)Key Natural Science Foundation of Yunnan Province China(2018FA28)for providing the financial support。
文摘The side reaction between the active material and liquid-electrolyte cause structural damage and particle pulverization is one of the important factors leading to the capacity decay of LiNi0.80Co0.15Al0.05O2(NCA)materials in Li ion batteries(LIBs).Surface modification is an effective strategy for NCA cathodes,which could alleviate the degradation associated with surface processes.Herein,a surface structure rearrangement of NCA cathode secondary particles was reported by in-situ forming a solid electrolyte LiBO2.The LiBO2 is beneficial for alleviating the stress during charge/discharge process,thereby slowing down the rate of cracks formation in the secondary particles,which facilitates the Li+de-intercalation as well as prevents penetration of the liquid-electrolyte into the interior of the particles.As a result,the surface structure rearrangement NCA(RS-NCA)delivers a high discharge capacity of 202.5 m Ah g^-1 at 0.1 C,and exhibits excellent cycle stability with discharge capacity retaining 148 m Ah g^-1 after 200 cycles at 2 C.This surface structure rearrangement approach provides a new viewpoint in designing high-performance high-voltage LIBs.
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%。
文摘以Li_2CO_3为锂源,采用纳米砂磨辅助固相合成了纯相LiNi_(0.8)Co_(0.15)Al_(0.05)O_2正极材料,研究了Li_2CO_3加入方式对所得样品结构、形貌以及电化学性能的影响.结果表明,加锂方式基本不影响材料的形貌和尺寸,但对材料的微结构和性能有明显的影响.纳米砂磨一步混合所有原料烧结所得LiNi_(0.8)Co_(0.15)Al_(0.05)O_2样品的阳离子混排程度比后研磨加碳酸锂烧结所得LiNi_(0.8)Co_(0.15)Al_(0.05)O_2样品的要低,更利于锂离子的扩散,对应的样品具有更高的放电比容量和库伦效率,但循环性能没有太大的差别.纳米砂磨一步混合所有原料在800℃烧结得到的LiNi_(0.8)Co_(0.15)Al_(0.05)O_2样品,1C循环首次放电比容量可达170.9 m Ah/g,50次循环后容量保持率为92.6%.
