The novel organophosphorus-containing lithium salt Li(THF)-[(C2O4)B(O2PPh2)(2)] (1; THF = tetrahydrofuran) was synthesized and characterized using a variety of spectroscopic techniques. An X-ray structural analysis on crystals of 1 grown from THF reveals a dimeric structure [Li(THF)(C2O4)B(O2PPh2)(2)](2)center dot THF, whereby the two units of 1 are bridged via P-O ... Li interactions. Compound 1 displays high air and water stability and is also thermally robust, properties needed of electrolytes for their possible use as electrolytes and/or additives in lithium-ion battery applications.