Battery lithium-fluorine

Many types of ECSCs have yet another advantage, that is, their environmental safety. The fact is that, for example, billions of lithium batteries are thrown to garbage dumps or buried in the earth and pollute the environment after their lifecycle is over. Thus, such toxic elements as lithium, fluorine, sulfur, nickel, and so on are released. As opposed to this, the widespread types of ECSCs with carbon electrodes and aqueous electrolytes are quite environment-friendly, that is, practically safe. 

Kobayashi, M. Inoguchi, T. lida, T. Tanioka, T. Kumase, H. Fukai, Y, Development of direct fluorination technology for application to materials for lithium battery, J. Fluorine Chem. 2003,120, 105-110. 

Abe, K. Hattori, X Kuwata, X Matsumori, Y., lithium secomlary battery employing fluorine-substituted cyclohexylbenzene containing electrolytic solution US Patent 7,537,861 (Ube Industries Ltd.) 2004 (applied in 2002). 

Azimi N, Weng W, Takoudis C, Zhang Z (2013) Improved performance of lithium-sulfur battery with fluorinated electrolyte. Electrochem Commun 37 96-99... 

Besides F-EPE, many other fluorinated ethers are synthesized by the addition reaction of tetrafluoroethylene with fluorinated and non-fluorinated alcohols. Some of the new structures may have superior properties to F-EPE as electrolyte solvents for Li-ion batteries and beyond Li-ion batteries. Recently, F-EPE was investigated for the first time as the electrolyte solvent in the lithium-sulfur battery [12]. The new fluorinaled electrolyte DOL/F-EPE-1.0 M LiTFSl suppressed the deleterious shuttling effect and improved the capacity retention and coulombic efficiency in Li-S cell tests. In addition, it was found to eliminate the self-discharge of lithium-sulfur batteries. Another fluorinated ether, bis(2,2,2-trifluoroethyl) ether (BTFE), was reported... 

Wu X, Zong X, Yang Q, Jin Z, Wu H (2001) Electrochemical studies of substituted spinel LiAlyMn2 y04 j,Fj, for lithium secondary batteries. J Fluorine Chem 107 39 14... 

Touhara, H. Suganuma, S. Okino, F., "Lithium Batteries with Fluorine-Graphite Intercalation Compound Cathodes. Post-Graphite Fluoride Cathode," Tanso 1991,150, 328. 

Fluorinated carbon, CFX, where x is between 0 and 1.3, is prepared by the direct fluorination of carbon at high temperatures [108]. Many varieties of fluorinated carbon can be prepared depending on the type of carbon used in the process (e.g. graphite, petroleum coke, carbon black, etc.) and the level of fluorination (i. e. the value of ). Fluorinated carbons, such as those manufactured by Allied-Signal (Accufluor ), Central Glass Co. (Cefbon ) and Daikin, are used for the fabrication of cathodes in lithium anode batteries and as solid lubricants [109]. 

Not yet widely exploited, but with quite some potential for fine-tuning of properties certainly is the stepwise fluorination of oxides. With LiCo02 cathode material for use in lithium secondary batteries, addition of small amounts of LiF considerably improved electrochemical properties [350], However, further exploitation is needed to elucidate if improvements are due to improved particle size and crystallinity or also due to minor fluorine content of the material. Lithium batteries are discussed in consecutive Chapters 15 and 16. 

As discussed above, LiPF6 and LiBF4 decompose to form HF in nonaqueous electrolyte solution. In addition, HF is often used as a fluorinated agent or a reaction medium when fluorine compounds are prepared. A trace of HF possibly remains in the salts and dissolved in nonaqueous electrolyte solution. Usually, HF was a typical undesirable species for battery system, but its function was not understood well before. Recently, a lot of reports have been published to discuss several chemical reactions of HF with the components contained in rechargeable lithium batteries. A very interesting behavior has been observed on lithium metal. 

Thus, the chemistry of HF in nonaqueous electrolyte solution is very important even though its content is in the order of 100 ppm. Therefore, much attention has to be paid on the synthesis and stability of fluoride compounds in nonaqueous electrochemistry and battery field. In particular, new compounds containing fluorine would be more and more important to realize more reliable nonaqueous electrolyte system and interface control in rechargeable lithium batteries. 

Fluorine containing organic compound is also important to prepare solid polymer electrolyte, which is very attractive as a novel electrolyte system [72-74]. At the initial stage of polymer electrolyte development, simple electrolyte salts, such as LiPF6 and LiC104, are used in rechargeable lithium batteries. However, their... 

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