Compatibility between Lithium Bis(oxalate)borate‐Based Electrolytes and a LiFe_0.6Mn_0.4PO₄/C Cathode for Lithium‐Ion Batteries

Abstract

The lithium transition‐metal phosphate LiFe0.6Mn0.4PO4 has two operating potentials, 3.5 V and 4.1 V, which is favorable for increasing the energy and power densities of lithium‐ion batteries (LIBs). To study the compatibility between LiFe0.6Mn0.4PO4 and electrolytes, lithium bis(oxalate)borate (LiBOB) is chosen as the lithium salt, based upon ethylene carbonate (EC), dimethyl carbonate (DMC), and dimethyl sulfite (DMS) as the supporting electrolyte solvents. The electrochemical performances of lithium hexafluorophosphate (LiPF6)‐based and LiBOB‐based electrolytes are compared. The combination of LiBOB and DMS can facilitate the formation of an effective passivation film. In addition, LiBOB‐EC/DMS electrolyte exhibits better cycle and rate performance. The results suggest that LiBOB‐EC/DMS electrolyte has good compatibility with LiFe0.6Mn0.4PO4, which makes it an attractive electrolyte for rechargeable LIBs based upon LiFe0.6Mn0.4PO4 cathodes.

Transport and Association of Ions in Lithium Battery Electrolytes Based on Glycol Ether Mixed with Halogen-Free Orthoborate Ionic Liquid

“…Orthoborate-based salts are believed to be more efficient than the conventional salt such as LiPF 6 because they offer several advantages such as good thermal stability, high compatibility with cathode materials, no erosion of manganese and iron cathode materials, and are also halogen-free and non-toxic 13 , 14 . A variety of orthoborate-based lithium salts and their derivatives such as lithium bis[1,2-benzenediolato(2-)-O,O′]borate Li[BBB] 15 , lithium bis[2,3-naphtha-lene-diolato(2-)-O,O′]borate Li[BNB] 16 , lithium bis[2,2-biphenyldiolato(2-)-O,O′]borate Li[BBPB] 17 , lithium bis[croconato]borate Li[BCB] 18 and lithium bis(salicylato)borate Li[BScB] 19 , 20 have been studied in different organic solvents as electrolytes for lithium-ion batteries.…”

Prospective Application, Mechanism, and Deficiency of Lithium Bis(oxalate)Borate as the Electrolyte Additive for Lithium‐Batteries

“…Low ionic conductivity and poor diffusion of lithium ions increase the internal resistance of the battery and increase the polarization of the battery, which in turn affects the multiplicity and low temperature performance of the battery. [ 64 ] In addition to aforementioned drawbacks, the low Coulomb efficiency of LiBOB at voltages above 4.7 V, and impurities such as water that are difficult to remove during synthesis, which also affect its performance.…”