Lithium-ion batteries (LIBS) for electric vehicles and aviation require high energy density, fast charging, and a wide operating temperature range, which is nearly impossible because they require electrolytes with high ionic conductivity, low solvation energy, and low melting points at the same time, as well as the formation of anion-derived inorganic interfaces.
Here, Hu Enyuan from Brookhaven National Laboratory in the United States, Chunsheng Wang from the University of Maryland, andZhejiang University (Unit 1).Fan Xiulin et al. reported guidelines for designing this electrolyte by using small-sized solvents with low solvation energy. Related ** is entitled“ligand-channel-enabled ultrafast li-ion conduction”Published on February 28, 2024natureAbove.
It has been found that the ideal electrolyte requires two contradictory properties: high salt dissociation but low Li+ transport energy barrier and high ionic conductivity but rich inorganic interface, which cannot be achieved at the same time. Using the ligand channel facilitation mechanism, the researchers designed a unique electrolyte (13 M lifsi fan), with a small solvation sheath and rapid solvent-desolubilization capacity. At 25 and 70, the ionic conductivity of the fan-based electrolyte was 40., respectively3 ms cm 1 and 119 ms cm−1。Fast charge transfer kinetics were realized, which promoted the formation of conductive LIF Lixn SEIs, and overcame the hysteresis kinetics of graphite under ultrafast charging and ultra-low temperature conditions.
The investigators used the ||The NMC811 graphite full battery has a cycle life of 3000 cycles at 6C and 109 cycles at -80 charge/dischargeHigh reversible capacity of 7 mAh g 1. Practical 12 ah graphite ||The NMC811 bag battery uses a FAN electrolyte with a reversible capacity of 073 Ah ( Reversible capacity at 65 °C is 062 ah) with no volume decay after 150 cycles.
This work reveals:The transport of ions between the medium and the structural mechanism is understood. The ligand channel-facilitating conduction mechanism paves the way for high-energy cells to operate under extreme conditions.