Page 89 - Handbook of Battery Materials
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2.6 Coin-Type Lithium Secondary Batteries  55

               Table 2.9  Specifications of cylindrical lithium–thionyl chloride batteries.

               Model        Nominal      Nominal       Dimensions (mm)   Weight
                           voltage (V)  capacity (mAh)                     (g)
                                                     Diameter   Height

               ER3V P         3.6         1000        19.5       24.5      8.5
               ER4V P         3.6         1200        19.5       24.5     10
               ER6V P         3.6         2000        19.5       47.0     16
               ER6LV P        3.6         1800        19.5       47.0     16
               ER17330V P     3.6         1700        20.5       29.5     13
               ER17500V P     3.6         2700        20.5       47.0     19



               chloride is essentially insoluble and precipitates on the surfaces of the pores of
               the carbon cathode, forming an insulating layer which terminates the operation of
               cathode-limited cells [36].
                The battery, which features a high (3.6 V) operating voltage and wide operating
                                      ◦
               temperature range (−55 to 85 C) can serve as a memory backup power source.
               Table 2.9 shows their specifications [37].


               2.6
               Coin-Type Lithium Secondary Batteries


               2.6.1
               Secondary Lithium–Manganese Dioxide Batteries

               It has been [38] reported that MnO 2 has poor rechargeability [11, 12]. However,
               most investigations were on γ , γ/β, and β-MnO 2 , which are similar to the MnO 2
               used in primary Li–MnO 2 batteries. In γ/β-MnO 2 , an expansion of the crystal
               lattice occurs when Li ions are inserted into its crystal structure. However, the
                                +
               degree of expansion does not increase much after a large initial change at quite a
               low level of discharge. It was considered that, if MnO 2 contained a small amount of
               Li in its crystal structure beforehand, the reversibility of its crystal structure would
               be improved.
                In order to improve the rechargeability of γ/β-MnO 2 ,two types of
               lithium-containing manganese oxides, spinel LiMn 2 O 4 and heat-treated LiOH 3 .
               MnO 2 (composite dimensional manganese oxide: CDMO), were prepared.
               First, the discharge and charge curves of γ/β-MnO 2 , spinel LiMn 2 O 4 , and
               CDMO were measured. The cycle tests and discharge tests were carried out
               with flat–cells, with Li–Al alloy as the negative electrode; the electrolyte was
               1mol L −1  LiClO 4 –PC/DME. The results are shown in Figure 2.38: when spinel
               LiMn 2 O 4 capacity and CDMO were discharged to 2 V, both showed stable
               curves.
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