Deciphering the potential of potassium-ion batteries beyond room temperature

Alloying-type anode materials are considered promising candidates for next-generation alkali-ion batteries.However,they face significant challenges owing to severe volume variations and sluggish kinetics,which hinder their practical applications.To address these issues,we propose a universal synthetic strategy,which can realize the facile synthesis of various alloying-type anode materials composed of a porous carbon matrix with uniformly embedded nanoparticles(Sb,Bi,or Sn).Besides,we construct the interactions among active materials,electrolyte compositions,and the resulting interface chemistries.This understanding assists in establishing balanced kinetics and stability.As a result,the fabricated battery cells based on the above strategy demonstrate high reversible capacity(515.6 mAh g1),long cycle life(200 cycles),and excellent high-rate capability(at 5.0 C).Additionally,it shows improved thermal stability at 45 and 60C.Moreover,our alloying-type anodes exhibit significant potential for constructing a 450 Wh kg1 battery system.This proposed strategy could boost the development of alloying-type anode materials,aligning with the future demands for low-cost,high stability,high safety,wide-temperature,and fast-charging battery systems.

Unlocking the decomposition limitations of the Li2C2O4 for highly efficient cathode preliathiations

The development of high-energy-density Li-ion batteries is hindered by the irreversible capacity loss during the initial charge-discharge process.Therefore,pre-lithiation technology has emerged in the past few decades as a powerful method to supplement the undesired lithium loss,thereby maximizing the energy utilization of LIBs and extending their cycle life.Lithium oxalate(Li_(2)C_(2)O_(4)),with a high lithium content and excellent air stability,has been considered one of the most promising materials for lithium compensation.However,the sluggish electrochemical decomposition kinetics of the material severely hinders its further commercial application.Here,we introduce a recrystallization strategy combined with atomic Ni catalysts to modulate the mass transport and decomposition reaction kinetics.The decomposition potential of Li_(2)C_(2)O_(4)is significantly decreased from~4.90V to~4.30V with a high compatibility with the current battery systems.In compared to the bare NCM//Li cell,the Ni/N-rGO and Li_(2)C_(2)O_(4)composite(Ni-LCO)modified cell releases an extra capacity of~11.7%.Moreover,this ratio can be magnified in the NCM//SiOx full cell,resulting in a 30.4%higher reversible capacity.Overall,this work brings the catalytic paradigm into the pre-lithiation technology,which opens another window for the development of high-energy-density battery systems.