The LiMBO 3 (M=Mn, Fe, Co) compounds were synthesized by a solid state reaction. LiFeBO 3 and h-LiMnBO 3 crystal structures were determined from single crystal data. LiFeBO 3 exhibits the same structure as that of other already described LiMBO 3 compounds (M=Mg, Mn, Co, Zn). The structure of h-LiMnBO 3 is isotypic with the hexagonal form of LiCdBO 3 . The electrochemical study shows that a very small amount of lithium (less than 0.04 Li per formula unit) can be deinserted reversibly from the three compounds. According to the thermodynamic study performed in the case of LiFeBO 3 , the Fe 3 + /Fe 2 + redox couple lies between 3.1 and 2.9 V/Li, demonstrating an important inductive effect of the BO 3 group.