Dual-salt electrolyte organic magnesium battery -Lithium - Ion Battery Equipment
However, the disadvantages of slow intra-lattice migration of magnesium ions and low theoretical capacity of inorganic frameworks still limit the wide application of magnesium batteries. The lithium-magnesium double-salt electrolyte system can realize the activation of the positive extreme kinetics by intercalating the dominant lithium ions (instead of magnesium ions) into the positive electrode lattice, without sacrificing the stability of the magnesium metal negative extreme cycling process, and avoiding the magnesium ion kinetics The disadvantage of poor performance greatly expands the selection range of cathode materials for magnesium batteries. Recently, a team led by Li Chilin, a researcher at the Shanghai Institute of Ceramics, Chinese Academy of Sciences, proposed a class of organomagnesium batteries activated by double-salt electrolytes for multi-electron reactions.
Nanostructured organic systems with high density of carbonyl groups (C=O) as redox reaction sites can achieve reversible capacities up to 350-400mAh/g (three-electron transfer), which can be further achieved by reducing graphene oxide (RGO) wiring High-rate electrochemical performance, its capacity can still be maintained at 200 and 175mAh/g at current densities of 2.5A/g (5C) and 5A/g (10C), respectively. The high-rate performance also benefits from high current and long cycling. There is still no dendrite formation in the magnesium anode under these conditions. This excellent performance benefits from the high intrinsic diffusion coefficient of Li in Na2C6O6 (10-12-10-11 cm2/s) and the pseudocapacitive contribution greater than 60%, the stronger non-Li pinning effect (via Na-O-C and Mg- O-C realization) can inhibit the exfoliation of the C6O6 layer in the grains and achieve up to at least 600 charge-discharge cycles. The energy density of the cathode active material of this organomagnesium battery can exceed 500Wh/kg and can tolerate power densities over 4000W/kg, which exceeds the level of high-potential intercalation cathode materials based on inorganic structures.
The team has long been committed to the research on the kinetic improvement strategy of magnesium-based batteries. In the early stage, magnesium fluoride graphene batteries with anion intercalation activation and reaction center exposure have been developed, and double-salt magnesium-based batteries based on large-capacity polysulfide conversion reactions have been developed. , the realization of high-rate, long-cycle Mg-S batteries is proposed.