Catalyst Research Corporation

Fig. 9.8 Variation of cell voltage and internal resistance during discharge of a Li(s)lLil(s)IP2VP.nf>(s) cell. (By permission of Catalyst Research Corporation.)...

Fig. 9.9 Lithium-iodine solid state button cell for electric watches and pocket calculators. (By courtesy of Catalyst Research Corporation.)...

Larger button cells with rated capacities in the range 35-lOOOmAh are manufactured for direct mounting on printed circuit boards where they are used as standby power sources for CMOS RAMs, reference voltage sources, etc. Fig. 9.10 shows the construction of these cells and the position of the terminal/mounting pins. Projected discharge curves for Catalyst Research Corporation cells are given in Fig. 9.11. 

Solid electrolyte lithium batteries have been produced for low-drain applications. The Catalyst Research Corporation produce a lithium-iodine solid electrolyte system, rated at 20,uA for heart pacemaker use. 

There are in fact many other types of lithium cell at present under commercial consideration, and a range of lithium cells that have been considered by the Catalyst Research Corporation for use for watch and calculator applications is discussed below. 

Table 9.6 shows the lithium systems available for commercial use from Catalyst Research Corporation. Most are button cells approximately 20-30mm in diameter and 1.5-3mm thick. All are high-voltage cells with moderate or high internal resistances. The first two have seen use in watches or calculators only the remaining three have also been used in the pacemaker field. 

Table 9.6 Types cf lithium cell availablefrom Catalyst Research Corporation...

A full specification of the Catalyst Research Corporation current pacemaker battery model 802123 is given in Table 9.14. The projected eleetrieal performance over an 18-20-year period is shown in Figure 9.10. 

Figure 9.10 Catalyst Research Corporation lithium-iodine Pacemaker Mxld 802123 projected performance 20 years (Courtesycf Catalyst Research Cor ration)...

Catalyst Research Corporation have designed and developed a high-efficiency electrochemical system for use in high current density applications. This Power Cell system has the flexibility for use in both short-and long-life battery requirements. Available power output is approximately 25% greater than that of conventional thermal battery systems. Performance data on this battery are given in Table 60.3. 

Catalyst Research Corporation also supply fast-activation thermal batteries. These are to meet the needs of applications requiring battery power to fire squibs, electric matches, dimple motors, explosive bolts, etc., after battery activation. 

Table 13.1 Firing energies cf Catalyst Research Corporation ealeium anode thermal batteries...

Catalyst Research Corporation (USA) is a major manufacturer of lithium—iodine batteries used for pacemaker and other applications. The Catalyst Research Series 800 cells use the lithium envelope concept. The cell is constructed with a centrally located cathode current collector and a lithium envelope which surrounds and contains the iodine depolarizer material (Figure 24.14). This depolarizer material is corrosive to the stainless steel case and must be kept irxnn contacting the case for maximum cell life. A second barrier, formed from fluorocarbon plastics, surrounds the lithium envelope, insulates it from the case, and provides a second envelope for the containment of the depolarizer. The corrosive effect of iodine-containing depolarizer on stainless steel is lower than that of depolarizer made with more active halogens, such as bromine or chlorine. 

Figure 24.15 Projected performance of Catalyst Research Corporation LIthlode TM lithium-iodine cells based on 5 years test data (Courtesy of Catalyst Research Corporation)...

Thermal batteries are manufactured in a wide range of configurations to suit various types of application. Some of the configurations available from Catalyst Research Corporation are illustrated in Figures 27.2-27.4. 

A typical design of a calcium chromate thermal cell produced by Catalyst Research Corporation (Figure 27.9) consists of a folded bimetal dumb-bell and pad of pyrotechnic paper. The catholyte disc consists of glass fibre tape impregnated with a molten mixture of lithium chloride, potassium chloride and potassium dichromate. The tape acts as a binding matrix for the molten salt when the battery is active. 

Many lithium cells are now available to the watch and calculator industry, but the designer should take care in selecting the right lithium cell for the application. Factors such as reliability, energy density, internal resistance and hermeticity should be considered. Since almost all lithium cells work best with a large area package. Catalyst Research Corporation propose standard button cell sizes of three diameters, 19,23 and 27 mm, and a range of thicknesses from 1 to 3 mm in... 

More recently. Catalyst Research Corporation have issued a preliminary specification sheet for a 7.5 A h... 

Of all the lithium compositions, lithium-iodine is considered by its inventor, Catalyst Research Corporation, to be a completely solid-state cell (although the electi olyte is purported to have a tar-like , rather than rock-hard, consistency). 

According to Catalyst Research Corporation, in the case of a continuous dead short, the battery cells are protected by the formation of a film, which raises the internal impedance, thereby limiting current. This self-limiting effect makes lithium-iodine safer than those lower impedance chemistries that heat up and, in the larger sizes, even explode when shorted. 

Since 1972, Catalyst Research Corporation has been the supplier of lithium-iodine batteries for cardiac pacemakers and other medical implantable devices and, more recently, for other applications of these batteries. 

Figure 56.23 Catalyst Research lithium-iodine2.8Vcells. Voltage veniM capacityrelatlonship. Model902,2.8V, 2.1 Ah (singleanode) (Courtesyof Catalyst Research Corporation)...

Ta ble 56.24 Catalyst Research Corporation non-medical CRC range of llthlum-lodinebatteries... 

Catalyst Research Corporation supply the Lithiode range of disc-shaped lithium—iodine power sources with PC bound mounting for CMOS-RAM as standby power sources and for reference voltage sources and other low-current applications where the cell is the main power source. 

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