International audienceLiMBO3 (M = Fe, Co, Mn) has been identified as an interesting new cathode material for Li-ion batteries. It was shown to be difficult to synthesize the material as a pure phase and in a highly electrochemically active form. Here we report several methods for the successful preparation of LiFeBO3, including traditional ceramic and self-combustion reactions. By decreasing the particle size and introducing in situ carbon coating, conventionally ceramic-synthesized LiFeBO3/C yields a first discharge of 210 mA h g(-1) within the 1.5-4.5 V voltage window at a C/20 rate, 55 degrees C. Using high-resolution synchrotron X-ray diffraction, neutron powder diffraction and single crystal X-ray diffraction in combination with Li-6 NMR and Fe-57 Mossbauer spectroscopies, we present a ``1Fe 2Li'' complex cation distribution model for LiFeBO3 powder

The magnetic ordering within LiMBO3 compounds (M = Mn, Fe, and Co) has been explored by magnetization measurements and neutron powder diffraction. For all M, an incommensurately ordered magnetic phase is established on cooling, followed by a change to a commensurate long-range antiferromagnetic state below TN2 = 12(1) K for LiMnBO3, TN2 = 25(1) K for LiFeBO3, and TN2 = 12(1) K for LiCoBO3. For LiMnBO3, the magnetic ordering at T = 2 K exhibits a propagation vector k = (1, 0, 0) and consists of antiferromagnetic chains that are coupled antiferromagnetically to each other, the magnetic moments being oriented along the [001] direction. In contrast, the magnetic order at T = 2 K in LiFeBO3 and LiCoBO3 exhibits a propagation vector of k = (1/2, 1/2, 1/2) and consists of ferromagnetic chains that are antiferromagnetically coupled. The magnetic moments lie roughly along the [023] direction within the bc plane for LiFeBO3, and along the [301] direction within the ac plane for LiCoBO3. The moment orientations in both LiMnBO3 and LiFeBO3 suggest an Ising character arising from unquenched orbital momentum due to unusual trigonal bipyrimidal coordination environments. No evidence of Ising behavior is found in the case of LiCoBO3.