Construction of pseudocapacitive Li2-xLaxZnTi3O8 anode for fast and super-stable lithium storage

Lithium-ion capacitors (LICs) composed of battery-type anodes with large energy densities and capacitor-type cathodes with high power densities are considered as appealing energy-storage devices. Here, a LIC with good performance is constructed using active carbon (AC) as the cathode and Li1.95La0.05ZnTi3O8 (LL5ZTO) as the anode. LL5ZTO doped with La is synthesized via a one-step solid-state route. The kinetics and structural stability of LZTO are enhanced by La-doping. Thus, LL5ZTO exhibits good Li-storage performance. The discharge specific capacity reaches 182.6 mAh g(-1) at 3 A g(-1) (120th cycle) for LL5ZTO. The LIC based on the LL5ZTO anode and the AC cathode delivers an energy density of 59.72 Wh kg(-1) at 846.4 W kg(-1), and a high power density of 8771 W kg(-1) at 19.49 Wh kg(-1). Furthermore, the capacity retention is over 90% after 3000 cycles for the LIC at 2 A g(-1). The good electrochemical performance indicates that the constructed LIC is expected to use in advanced energy storage devices.

Automated summary

By utilizing La-doped LL5ZTO as the anode and active carbon (AC) as the cathode, a high-performance lithium-ion capacitor (LIC) is constructed, showing good lithium storage performance, high energy density, and power density. The capacity retention rate of the LIC is over 90% after 3000 cycles, indicating its potential for advanced energy storage devices.