A New Class of Electrochemically and Thermally Stable Lithium Salts for Lithium Battery Electrolytes. V. Synthesis and Properties of Lithium Bis[2,3-pyridinediolato(2−)-O,Oʹ]borate

Abstract

Currently various new salts are synthesized to resolve problems associated with electrolytes of primary and secondary lithium batteries. The latest developments include 1,2 1. Lithium salts which are based on the well-known tris(trifluoromethylsulfonyl) methide and bis(trifluoromethylsulfonyl) imide, i.e., variants, such as the cyclic imide Liwhere n ϭ 1-3, 4 the asymmetric methide Li[C(SO 2 CF 3 ) 2 (SO 2 C 4 F 9 )], and the bismethide Li 2 [C 2 (SO 2 CF 3 ) 4 (S 2 O 4 C 3 F 6 )], both synthesized by Sartori et al. 5 2. Lithium imides with new ester type substituents and imides with long fluoroalkyl groups. 6 3. The family of chelatoborates, developed in our laboratory. [7][8][9][10][11][12] 4. A similar class of chelatophosphates where the tetracoordinated boron with two ligands is substitued by the hexacoordinated phosphorous with three ligands. 13 5. A new approach is based on ligands which, instead of solvating cations, 14 displace cations in ion pairs by anion solvation. This is made possible by the strong interaction of the anions with aza-ether compounds. 15 Electron withdrawing substituents such as CF 3 SO 2 Ϫ

Structures of Orthoborate Anions and Physical Properties of Their Lithium Salt Nonaqueous Solutions

“…The implied high degree of dissociation confirms the conclusions of our earlier work based on conductivity vs. temperature data [2]. e The presence of two proton resonances in the case of LiBMB in DMSO-d 6 , one due to normal impurities, allowed us to approximately determine the solvent diffusivity, which was ca. 2D BMB− .…”

“…These salts, in particular those based on dicarboxylate capping of the orthoborate oxygens, show particular promise for replacing the fluorinated lithium salts, such as LiPF 6 and Li bis(trifluoromethanesulphonyl) imide (LiTFSI), that are in widespread use at the moment. Not only do the new salts yield non-aqueous solutions of exceptional conductivity, but also they have wide electrochemical windows.…”

Crystal structure of dimethylammonium bis(salicylato)borate, [NH2(CH3)2][BO4(C7H4O)2]

“…In contrast, synthesis and crystal structures of organic borates seem to be insufficient [5][6][7]. To date, alkali-metal bis(salicylato)borates were studied intensively [5][6], from which the lithium organoborates had been considered as the lithium battery electrolytes [8]. Herein, we extend the studies of organic borates with the crystal structure of a bis(salicylato)borate, namely NH 2 can also be expressed as BL2 form (H 2L = salicylic acid).…”

Crystal structure of dimethylammonium bis(salicylato)borate, [NH2(CH3)2][BO4(C7H4O)2]

“…In contrast, synthesis and crystal structures of organic borates seem to be insufficient [5][6][7]. To date, alkali-metal bis(salicylato)borates were studied intensively [5][6], from which the lithium organoborates had been considered as the lithium battery electrolytes [8]. Herein, we extend the studies of organic borates with the crystal structure of a bis(salicylato)borate, namely NlfeiCIfe^IBC^^ILiO^].…”