Composite cathodes integrating Ni-rich layered oxides and oxide solid electrolytes are essential for highenergy all-solid-state lithium-ion batteries(ASSLBs),yet interfacial degradation during high-temperature co-sint...Composite cathodes integrating Ni-rich layered oxides and oxide solid electrolytes are essential for highenergy all-solid-state lithium-ion batteries(ASSLBs),yet interfacial degradation during high-temperature co-sintering(>600℃)remains a critical challenge.While surface passivation strategies mitigate reactions below 400℃,their effectiveness diminishes at elevated temperatures due to inability to counteract Li^(+)concentration gradients.Here,we introduce in situ lithium compensators,i.e.,LiOH/Li_(2)CO_(3),into NCM-LATP composite cathodes to dynamically replenish Li^(+)during co-sintering.These additives melt to form transient Li^(+)-rich phases that back-diffuse Li^(+)into NCM lattices,suppressing layered-to-rock salt transitions and stabilizing the interface.Quasi in situ XRD confirms retention of the layered structure at temperature up to 700℃,while electrochemical tests demonstrate a reversible capacity of 222.2 mA h g^(-1)—comparable to NCM before co-sintering—and an impressive 65.3% capacity retention improvement over100 cycles.In contrast,uncompensated cathodes exhibit severe degradation to 96.5 mA h g^(-1)due to Li depletion and resistive Li-Ti-O interphases.This strategy integrates sacrificial chemistry with scalable powder-mixing workflows,achieving a 93.4% reduction in interfacial impedance.By addressing Li^(+)flux homogenization and structural stability,this work provides a practical pathway toward industrialscale fabrication of high-performance ASSLBs.展开更多
基金financially supported by the National Natural Science Foundation of China(52102206)the Natural Science Foundation of Beijing Municipality-Shunyi Innovation Collaborative Joint Fund(L247018)+2 种基金the Natural Science Foundation of Beijing Municipality(2254076 and 2252024)the Central Guidance on Local Science and Technology Development Fund of Hebei Province(246Z4412G)the Fundamental Research Funds for the Central Universities(2025MS022,North China Electric Power University)。
文摘Composite cathodes integrating Ni-rich layered oxides and oxide solid electrolytes are essential for highenergy all-solid-state lithium-ion batteries(ASSLBs),yet interfacial degradation during high-temperature co-sintering(>600℃)remains a critical challenge.While surface passivation strategies mitigate reactions below 400℃,their effectiveness diminishes at elevated temperatures due to inability to counteract Li^(+)concentration gradients.Here,we introduce in situ lithium compensators,i.e.,LiOH/Li_(2)CO_(3),into NCM-LATP composite cathodes to dynamically replenish Li^(+)during co-sintering.These additives melt to form transient Li^(+)-rich phases that back-diffuse Li^(+)into NCM lattices,suppressing layered-to-rock salt transitions and stabilizing the interface.Quasi in situ XRD confirms retention of the layered structure at temperature up to 700℃,while electrochemical tests demonstrate a reversible capacity of 222.2 mA h g^(-1)—comparable to NCM before co-sintering—and an impressive 65.3% capacity retention improvement over100 cycles.In contrast,uncompensated cathodes exhibit severe degradation to 96.5 mA h g^(-1)due to Li depletion and resistive Li-Ti-O interphases.This strategy integrates sacrificial chemistry with scalable powder-mixing workflows,achieving a 93.4% reduction in interfacial impedance.By addressing Li^(+)flux homogenization and structural stability,this work provides a practical pathway toward industrialscale fabrication of high-performance ASSLBs.
