Regulating interfacial chemistry and kinetic behaviors of F/Mo co-doping Ni-rich layered oxide cathode for long-cycling lithium-ion batteries over-20°C-60°C

Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature conditions(below0°C and above 50 °C).Here,we report the design of F/Mo co-doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(FMNCM)cathode for high-performance LIBs from-20 to 60°C.F^(-) doping with high electronegativity into the cathode surface is found to enhance the stability of surface lattice structure and protect the interface from side reactions with the electrolyte by generating a LiF-rich surface layer.Concurrently,the Mo^(6+) doping suppresses phase transition,which blocks Li^(+)/Ni^(2+) mixing,and stabilizes lithium-ion diffusion pathway.Remarkably,the FMNCM cathode demonstrates excellent cycling stability at a high cutoff voltage of 4.4 V,even at 60°C,maintaining 90.6%capacity retention at 3 C after 150 cycles.Additionally,at temperatures as low as-20°C,it retains 77.1%of its room temperature capacity,achieving an impressive 97.5%capacity retention after 500 cycles.Such stable operation under wide temperatures has been further validated in practical Ah-level pouch-cells.This study sheds light on both fundamental mechanisms and practical implications for the design of advanced cathode materials for wide-temperature LIBs,presenting a promising path towards high-energy and long-cycling LIBs with temperatureadaptability.

Ammonium-ion batteries with a wide operating temperature window from-40 to 80℃

Ammonium-ion batteries are promising solutions for large-scale energy storage systems owing to their costeffectiveness,safety,and sustainability.Herein,we propose an aqueous ammonium-ion battery based on an organic poly(1,5-naphthalenediamine)anode and an inorganic Prussian blue cathode in 19 M(M:mol kg^(-1))CH3COONH_(4)electrolyte.Its operation involves a reversible coordination reaction(C=N/C-N-conversion)in the anode and the NH_(4)^(+)insertion/extraction reaction in the cathode,along with NH_(4)^(+)acting as the charge carrier in a rocking-chair battery.Benefiting from the fast kinetics and stability of both electrodes,this aqueous ammoniumion battery shows an excellent rate capability and long cycle stability for 500 cycles.Moreover,an energy density as high as 31.8 Wh kg^(-1) can be achieved,based on the total mass of the cathode and anode.Surprisingly,this aqueous ammonium-ion battery works well over a wide temperature range from-40 to 80℃.This work will provide new opportunities to build wide-temperature aqueous batteries and broaden the horizons for large-scale energy storage systems.

Monolithic integration of electroabsorption modulators and tunnel injection distributed feedback lasers using quantum well intermixing

Electroabsorption modulators combining Franz-Keldysh effect and quantum confined Stark effect have been mono-lithically integrated with tunnel-injection quantum-well distributed feedback lasers using a quantum well intermixing method. Superior characteristics such as extinction ratio and temperature insensitivity have been demonstrated at wide temperature ranges.

Julolidine functionalized benzimidazoline-doped fullerene derivatives for efficient and stable perovskite solar cells

Fullerene derivatives are highly attractive materials in solar cells,organic thermoelectrics,and other devices.However,the intrinsic low electron mobility and electrical conductivity restrict their potential device performance,such as perovskite solar cells(PSCs).Herein,we successfully enhanced the electric properties and morphology of phenyl-C61-butyric acid methyl ester(PCBM)by n-doping it with a benzimidazoline derivative,9-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)-julolidine(JLBI-H)via a solution process.We found the n-doping can not only improve the conductivity and optimize the band alignment but also enable the PCBM to have a constantly strong charge extraction ability in a wide temperature from 173 to 373 K,which guarantees a stable photovoltaic performance of the corresponding PSCs under a wide range of operating temperatures.With the JLBI-H-doped PCBM,we improved the efficiency from 17.9%to 19.8%,along with enhanced stability of the nonencapsulated devices following the aging protocol of ISOS-D-1.