Certain glymeLi salt complexes, which are composed of equimolar mixtures of a glyme and a Li salt, are liquid under ambient conditions with physicochemical properties such as high thermal stability, wide potential window, high ionic conductivity, and high Li + transference number and can be regarded as a new family of room-temperature ionic liquids.Room-temperature ionic liquids (RTILs), which are liquid at room temperature and composed entirely of ions, have attracted much attention because of their unique properties such as nonflammability, low-volatility, high chemical stability, and high ionic conductivity.1 RTILs are expected to be applied to electrochemical devices, including electric double-layer capacitors, 2 fuel cells, 3 dye-sensitized solar cells, 4 and lithium ion batteries (LIBs).5 Most of the RTILs reported to date can be classified as combinations of weakly Lewis-acidic cations and weakly Lewis-basic anions, which leads to ionic dissociation without strong coordination of solvent molecules around each ion. Thus, the most common compositions of RTILs are combinations of onium cations such as imidazolium cations, quaternary ammonium cations, and quaternary phosphonium cations and soft anions such as bis(trifluoromethylsulfonyl)-amide (TFSA ¹ ), tetrafluoroborate (BF 4 ¹ ), and hexafluorophosphate (PF 6 ¹ ). There are few reports of RTILs consisting of strongly Lewis-acidic cations such as Li + and Na + and strongly Lewis-basic anions such as F ¹ and Cl ¹ . Melting points of salts consisting of strongly Lewis-acidic cations and strongly Lewisbasic anions are generally much higher than room temperature, resulting in the formation of ionic crystals at room temperature. So far, we have reported the preparation of lithium ionic liquids consisting of lithium salts of borates having electron-withdrawing groups, to reduce the anionic basicity, and lithium coordinating ether-ligands, to dissociate the lithium cations from the anionic centers.6 However, possibly due to the strong Lewis acidity of Li + , the viscosity and ionicity (dissociativity) of the lithium ionic liquids at room temperature are as high as 500 mPa s and as low as 0.10.2, respectively, resulting in a low ionic conductivity of 10 ¹5 S cm ¹1 at its maximum. Weakly Lewis-basic anions such as BF 4 ¹ and PF 6 ¹ are prepared by the reactions between Lewis acids (BF 3 and PF 5 ) and a Lewis base (F ¹ ) by forming coordination bonds. However, the preparation of weakly Lewis-acidic cations for RTILs by the reaction between a Lewis acid and a Lewis base has not been proposed. It is anticipated that weakly Lewis-acidic cations can be prepared by the combination of alkali metal cations (Lewis acid) and suitable ligands (Lewis base).Ethers are relatively strong Lewis bases, and alkali metal cations are strongly coordinated with ethers. It is well-known that particular molar ratio mixtures of Li salts and oligoethers such as crown ethers, triglyme (G3), and tetraglyme (G4) form complexes. Henderson et al. have conducted a systematic study of glymeLi salt...

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The olivine-type compound LiMnPO 4 was prepared via a reaction between Li 3 PO 4 and a MnSO 4 aqueous solution under hydrothermal conditions at 190 • C. The specific surface area and particle morphology of LiMnPO 4 changed depending on the amount of water in the reaction mixtures, and the particle size decreased as the amount of water decreased. It was found that nanosized LiMnPO 4 particles of ca. 50 nm can be prepared through the reaction between Li 3 PO 4 and the molten aqua-complex of MnSO 4 •nH 2 O (n = 4 or 5). Galvanostatic charge and discharge tests revealed that the electrochemical reactivity of LiMnPO 4 at 30 • C increased as the particle size decreased. The small particle size contributes to the decrease in the overpotential for Mn 2+/3+ redox and to the increase in the utilization of LiMnPO 4 as an active material in the cathode of lithium batteries.Since the first report on LiFePO 4 by Goodenough et al., 1 olivinetype compounds, LiMPO 4 (M = Mn, Fe, Co, Ni), have been investigated extensively as promising cathode materials for lithium batteries. 2-7 LiFePO 4 has a highly stable three-dimensional framework due to strong P-O covalent bonds in PO 4 3− ; this framework prohibits the liberation of oxygen at elevated temperatures. 2 Therefore, LiFePO 4 is attractive as a thermally stable cathode material. A drawback of LiFePO 4 is its low electrical (electronic and/or ionic) conductivity, which causes the LiFePO 4 cathode to have a high resistance. 8-10 Therefore, nanosized LiFePO 4 was developed to decrease the electrical resistance within the particle. 2-4 In addition, carbon coating technologies for LiFePO 4 particles were developed to facilitate current collection from the particles. [11][12][13][14][15][16] Thanks to the increasing research and development activities, LiFePO 4 has been commercialized as a cathode material for lithium batteries. A next target of researchers in the field of lithium batteries is the development of high-performance LiMnPO 4 cathodes. [17][18][19][20] The redox reaction of Mn 2+/3+ in LiMnPO 4 takes place at the electrode potential of 4.1 V vs. Li/Li + , whereas that of Fe 2+/3+ in LiFePO 4 occurs at 3.5 V. LiMnPO 4 is a promising cathode material for 4 V-class lithium batteries. However, the slow kinetics of delithiation/lithiation of LiMnPO 4 due to the Jahn-Teller distortion caused by the generation of Mn 3+ during electrochemical reaction limits the utilization of LiMnPO 4 in practical lithium batteries. 21,22 To achieve a facile electrochemical reactivity, the particle size of LiMnPO 4 should be decreased, probably to a size smaller than that of commercialized LiFePO 4 .There are various methods to prepare nanosized LiMPO 4 particles, such as the carbothermal process, 23 spray-pyrorysis, 24 solgel method, 25, 26 polyol process, 27-29 and hydrothermal synthesis. [30][31][32][33][34][35][36][37][38] Among these methods, the hydrothermal synthesis and polyol process are attractive because the nucleation and growth of crystals take place in a liquid phase that allow us to...