The room temperature ͑x, y͒ two-dimensional phase diagram of the olivine-type solid-solution, Li x (Mn y Fe 1Ϫy )PO 4 (0 р x, y р 1, orthorhombic, D 2h 16 : Pmnb), is determined. The x-dependent changes in the unit cell dimensions at various fixed Mn contents y are analyzed in detail. The manganese substitution for iron in the octahedral 4c sites induces 1, the two-phase Mn . The conversion, 2, is complete at around y ϭ 0.6. The phase instability, 3, makes the Mn-rich phase (y Ͼ 0.8) unsuitable for battery applications. The local lattice deformation around Mn 3ϩ is severe enough to induce significant selective damping in the extended X-ray absorption fine structure for Mn The oxidation ͑charge͒ of LiM 2ϩ PO 4 to M 3ϩ PO 4 induces a reduction in the unit cell volume. This shrinkage compensates for the volume expansion of the carbon anodes in the charge process and contributes to efficient use of volume in a practical lithium-ion cell. The opposite movement of lithium ions and electrons occurs during the discharge process, while the transition metal M is reduced from trivalent to divalent.The LiMPO 4 crystal has an orthorhombic unit cell (D 2h 16 , space group Pmnb,) which accommodates four units of LiMPO 4 .11 As a typical example, LiFePO 4 has unit-cell dimensions of a ϭ 6.008(1) Å, b ϭ 10.324(2) Å, and c ϭ 4.694(1) Å. Graphic representations of the crystal structure have been given in many references. 1,3,4,11 Both the Li and M atoms are in octahedral sites with Li located in the 4a and M in the 4c positions. The oxygen atoms are nearly hexagonal closed-packed and the M atoms occupy zigzag chains of corner-shared octahedra running parallel to the c axis in alternate a-c planes. These chains are bridged by corner-and edge-sharing (PO 4 ͒ 3Ϫ polyanions to form a host structure with strong three-dimensional bonding. The Li ϩ ions in 4a sites form continuous linear chains of edge-shared octahedra running parallel to the c axis in the other a-c planes, which makes two-dimensional motion possible.The charge-discharge reaction of the presently used materials, such as the layered rock salt systems, LiCoO 2 , LiNiO 2 ͑space group, R3 m), and a spinel framework system Li 0.5 MnO 2 ͑space groups: Fd3m) are all based on the M 4ϩ /M 3ϩ couple in edge-shared MO 6 octahedra in the closed-packed oxygen array which generates ca. 4 V '' 1,6 The stable nature of the olivine-type structure having a (PO 4 ͒ 3Ϫ polyanion with a strong P-O covalent bond provides not only excellent cycle-life but also a safe system. When the battery is fully charged, the reactivity to the combustion reaction with the organic electrolyte is low.6 Safety issues are of paramount importance in the design of consumer batteries, and this makes olivinetype materials particularly attractive as cathodes for lithium-ion battery systems.The energy density of olivine-type LiMPO 4 is equal to that of presently used materials, based on the theoretical charge-discharge capacity of ca. 170 mAh/g obtained from the M 3ϩ /M 2ϩ one-electron redox reaction of Li x MPO ...

Background: Human peripheral blood monocytes (Mo) consist of subsets distinguished by expression of CD16 (FCγRIII) and chemokine receptors. Classical CD16 -Mo express CCR2 and migrate in response to CCL2, while a minor CD16 + Mo subset expresses CD16 and CX3CR1 and migrates into tissues expressing CX3CL1. CD16 + Mo produce pro-inflammatory cytokines and are expanded in certain inflammatory conditions including sepsis and HIV infection.

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The charge-discharge reaction mechanism of the olivine-type Li x ͑Mn 0.6 Fe 0.4 ͒PO 4 (0 р x р 1.0), a possible 4 V class cathode material for lithium batteries, was investigated using equilibrium voltage measurements, X-ray diffraction, Mössbauer spectroscopy, and X-ray absorption spectroscopy. The flat two-phase region with an open-circuit voltage ͑OCV͒ of ca. 4.1 V ͑region I: 0 р x р 0.6, Mn 3ϩ /Mn 2ϩ ͒ and the S-curved single-phase region with OCV Ϸ 3.5 V ͑region II: 0.6 р x р 1.0, Fe 3ϩ /Fe 2ϩ ͒ were clearly identified together with the corresponding change in the unit cell dimensions of the orthorhombic lattice. These features show significant differences from the reaction mechanism of Li x FePO 4 (0 р x р 1), in which the whole Fe 3ϩ /Fe 2ϩ reaction proceeds in a two-phase manner (LiFePO 4 -FePO 4 ) with a flat voltage profile at 3.4 V.Transition metal oxides that lithium can be repeatedly removed from and inserted into have been investigated as electrodes in rechargeable lithium batteries. Among them, layered rock salt systems ͑isostructural to ␣-NaFeO 2 ͒ Li x CoO 2 (0 р x р 1), 1 Li x NiO 2 (0 р x р 1), 2 and the manganese spinel framework system Li x ͓Mn 2 ͔O 4 (0 р x р 1) 3,4 are now used commercially as 4 V cathode materials because of their high battery voltage with large capacity, high energy density, and excellent cycle life. All of these materials were proposed in the early 1980s. In spite of intensive efforts devoted to finding alternative options with higher capacity, lower cost, and greater stability, no practical material had been identified for a long period.In 1997, it was reported that LiMPO 4 with an ordered olivine structure generates high voltage vs. Li/Li ϩ ͑3.4 and 4.1 V for M ϭ Fe and Mn, respectively͒ and cycles well at ambient temperature with a reversible capacity of 80-120 mAh/g. 5 Although this capacity was achieved only under very low current density and is much smaller than the theoretical value, 170 mAh/g, based on the M 3ϩ /M 2ϩ one-electron redox reaction, these findings by Padhi et al. aroused a great deal of interest both by the scientific community and by industry. [6][7][8][9][10][11] We have recently observed a reversible capacity of 160 mAh/g at room temperature for the optimized LiFePO 4 powder, which gives an energy density equal to those of presently used materials. 12 In the optimization process, we identified two main obstacles to achieving optimum charge/discharge performance: ͑i͒ the undesirable particle growth and ͑ii͒ the presence of residual Fe 3ϩ phase in the sintering process. 12 The stable nature of the olivine-type structure having a (PO 4 ͒ 3Ϫ polyanion with a strong P-O covalent bond provides not only excellent cycle life but also a safe system when the battery is fully charged. 12 The reactivity is low for the combustion reaction with the organic electrolyte. 12 LiMPO 4 crystal has an orthorhombic unit cell ͑D 2h 16 Ϫ Pmnb), which accommodates four units of LiMPO 4 . 13,14 As a typical example, the LiFePO 4 ͓a ϭ 6.008(1) Å, b ϭ 10.324(2) Å, c ϭ 4.694(...