Energy rechargeable cells

Figure 17. Specific energies and energy densities of rechargeable cells. Prepared from data kindly provided by Fujifilm Celltech Co., Ltd. 342],...

It should be added that nonaqueous electrolytes for high-energy rechargeable electrochemical cells developed by Aurbach and coworkers were patented for nse as solntions in organic solvents or as gel-type solids" . 

Fig. 7.25 Construction of a Li-MoS2 AA-sizcd rechargeable cell. (By permission of Moli Energy Lid.)...

Switching to lithium-alloy negative electrodes, some voltage loss must be noted. LiAl has Uu = -1-385 mV, Li4.5Pb has Uu = 388 mV. Entries 18-20 in Table 10(b) represent three examples of rechargeable cells, which have been, at least temporarily, commercialized. The first (No. 18) is due to a lithium alloy/carbon black battery conunercialized by the Matsushita Co. [248]. The lithium alloy components are Pb -I- Cd -I- Bi -h Sn (Wood s alloy). Button cells in the range 0.3 to 2.5 mAh were offered. The electrolyte was LiC104 in an unknown solvent. The practical energy densities, 2Wh/kg, were rather low. The c.b. positive electrode acts as a double... 

Normal batteries have the advantage of being relatively small, which makes them easily inserted, removed, and transported from place to place. Such batteries are limited in the amount of current they produce by the amount of the reagents inside the battery. When the oxidizable reagent in the battery is consumed, the battery is dead unless it is a rechargeable battery. One way to overcome this problem is to use fuel cells which, like batteries, have an electrode where oxidation takes place and an electrode where reduction takes place. However, fuel cells do not depend on chemicals stored inside the electrode compartments for their energy. Fuel cells produce energy from reactants that continuously flow into their compartments while the chemical reaction products flow out of them. 

Silver oxide/zinc can be manufactured in rechargeable cells with free potassium hydroxide electrolyte and pasted rectangular electrodes. Such cells are expensive but have a good energy density compared with Pb/acid or Ni/Cd (70 Wh kg ) and are also capable of high discharge rates for short periods. Other alkaline secondary batteries which have been manufactured include NiO(OH)/Zn, NiO(OH)/Fe and Ag2 0/Cd. 

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