Lithium/molybdenum disulfide batteries

Secondary lithium-metal batteries which have a lithium-metal anode are attractive because their energy density is theoretically higher than that of lithium-ion batteries. Lithium-molybdenum disulfide batteries were the world s first secondary cylindrical lithium—metal batteries. However, the batteries were recalled in 1989 because of an overheating defect. Lithium-manganese dioxide batteries are the only secondary cylindrical lithium—metal batteries which are manufactured at present. Lithium-vanadium oxide batteries are being researched and developed. Furthermore, electrolytes, electrolyte additives and lithium surface treatments are being studied to improve safety and recharge-ability. 

Lithium Molybdenum Disulfide LiiMoS Batteries. The Li/MoS2 system was the first rechargeable lithium battery to be manufactured when it was introduced in the mid-1980s in a cylindrical AA-size. The ceU used thin lithium metal anodes (125 /xm), with a stoichiometric excess of about three times, and M0S2 on a thin aluminum foil (150 /u.m) for the cathode. A spirally wound construction, as illustrated in Fig. 34.13, was used. The electrolyte was IM LiAsF(j dissolved in a 50 50 mixture of propylene carbonate and ethylene carbonate. Two types of batteries were manufactured. Table 34.12 describes the more advanced of the two. 

While the development of primary cells with a lithium anode has been crowned by relatively fast success and such cells have filled their secure rank as power sources for portable devices for public and special purposes, the history of development of lithium rechargeable batteries was full of drama. Generally, the chemistry of secondary batteries in aprotic electrolytes is very close to the chemistry of primary ones. The same processes occur under discharge in both types of batteries anodic dissolution of lithium on the negative electrode and cathodic lithium insertion into the crystalline lattice of the positive electrode material. Electrode processes must occur in the reverse direction under charge of the secondary battery with a negative electrode of metallic lithium. Already at the end of the 1970s, positive electrode materials were found, on which cathodic insertion and anodic extraction of lithium occur practically reversibly. Examples of such compounds are titanium and molybdenum disulfides. 

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