Batteries spirally wound cylindrical

Figure 1. Typical battery configurations (a) button cell (b) stack lead acid (c) spiral wound cylindrical lithium ion (d) spiral wound prismatic lithium-ion.

Li-FeS2 cells were manufactured as button cells, and are now produced as spiral wound cylindrical cells (Fig. 4.28). The latter are currently being heavily marketed worldwide by the Eveready Battery Co, Inc. (especially... 

Cells with rectangular electrodes are very similar to the battery in Fig. 10.13 except that the pins are replaced by a thin membrane, thus reducing the inter-plate gap and aiding the rapid discharge of the cell. Figures 10.14 and 10.15 show the designs of a spirally wound cylindrical cell and a button cell. 

Fig. 10.1 Typical Li-ion battery configuration (a) spirally wound cylindrical cell, (b) wound type...

The construction of the spiral-wound cylindrical battery is shown in Fig. 14.78. These batteries typically have several safety devices incorporated in their design to provide protection against such abusive conditions as short circuit, charging, forced discharge, and over heating. Two safety devices are shown in the figure—a pressure relief vent and a resettable thermal switch, called a positive thermal coefficient (PTC) device. The safety relief vent is designed to release excessive internal pressure to prevent violent rupture if the battery is heated or abused electrically. 

Batteries have been build in a spirally wound cylindrical D size. Table 34.15 lists the design parameters. This D-cell battery employed an alloy anode of 85% Li-15% Al. Figure 34.20a shows the discharge characteristics of the battery at several discharge rates and Fig. 34.20(> shows the cycle life characteristics. The declining capacity of the cell with cycling is attributed to increasing impedance of the cathode. ... 

A novel microporous separator using polyolefins has been developed and used extensively in lithium-ion batteries since it is difficult for conventional separator materials to satisfy the characteristics required in lithium-ion batteries. In lithium-ion batteries two layers of separators are sandwiched between positive and negative electrodes and then spirally wound together in cylindrical and prismatic configurations. The pores of the separator are filled with ionically conductive liquid electrolyte. 

The second design is the spirally wound electrode construction, typically used in sealed portable rechargeable batteries and high-rate primary and rechargeable lithium batteries (Fig. 3.2lb). In this design, the electrodes are prepared as thin strips and then rolled, with a separator in between, into a jelly roll and placed into the cylindrical can. This design emphasizes surface area to enhance high-rate performance, but at the expense of active material and capacity. 

The capacity retention after storage at 20°C is shown in Fig. 14.27. Like the other Li/ SOCI2 batteries, these batteries have an excellent storage capability over a wide temperature range due to the buildup of a protective lithium chloride layer on the lithium. This passivation layer, however, may cause a voltage delay under some discharge conditions. Table 14.12 lists the characteristics of typical cylindrical spirally wound Li/SOCl2 batteries. 

TABLE 14.12 Characteristics of Typical Cylindrical Spirally Wound Li/SOClj Batteries... 

These lithium/oxychloride batteries are available in hermetically sealed, spirally wound electrode cylindrical configurations, ranging from AA to DD size in capacities up to 30 Ah. These batteries are also available in the AA size containing 0.5 g of Li and in flat diskshaped cells. Figure 14.35 shows a cross section of a typical cell. Table 14.17 lists the different lithium-oxychloride batteries manufactured and their key characteristics. Two types of halogen-additive lithium/oxychloride batteries have been developed, as follows ... 

FIGURE 14.52 Midpoint voltage of cylindrical (spirally wound) Li/MnOj batteries during discharge 2-V end voltage. 

FIGURE 14.54 Summary of discharge characteristics of cylindrical (spirally wound) li/MnOj battery (CR123A size) capacity vs. discharge load to 2.0 V per cell, (a) Constant-resistance loads, (b) Constant-current loads. 

The cylindrical batteries use a spirally wound (jelly-roll) electrode construction, and the batteries are either crimped or hermetically sealed. Their construction is similar to the cylindrical spiral-wound electrode design of the Li/MnOz battery shown in Fig. 14.40. The larger cells are provided with low-pressure safety vents. 

Li/FeS2 batteries may be manufactured in a variety of designs, including the button and both bobbin and spiral-wound-electrode cylindrical cells. A bobbin constmction is most suitable for Ught-drain applications. The spiral-wound-electrode construction is needed for the heav-ier-drain applications, and it is this design that has been commercialized. 

Spirally Wound Cells. Cylindrical batteries in C and D sizes have been designed with spirally wound electrodes to meet higher drain requirements. Figure 14.93 shows the discharge performance of a Li/CuO D-size battery at various temperatures and at relatively low and high discharge rates. 

Pure lead is generally too soft to be used as a grid material. Exceptions that use pure lead plates are some special, very thick plate Plants or pasted-plate batteries, some small spiral wound batteries, some valve regulated cells and batteries (see Fig. 23.12c) and a cylindrical cell. The latter were developed by Bell Laboratories (now part of Lucent Technologies) (see Fig. 23.36). "... 

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