Jelly-roll cells

Polyacene PC (CH3CH2)4N+BF4- 2.5 V Coin cells Jelly-rolled cells — >1,000,000 Page 207... 

Activated carbon PC (CH3CH2)4N+BFC 2.5 V Jelly-rolled cells — — Page 213... 

Figure 19. Principle construction of a "jelly-roll" cell.

Both the lithium sulfur dioxide (Li-SO and lithium thionyl chloride (Li-SOCy cells may be classified as liquid cathode systems. In these systems, S02 and SOCl2 function as solvents for the electrolyte, and as the active materials at the cathode to provide voltage and ampere capacity. As liquids, these solvents permeate the porous carbon cathode material. Lithium metal serves as the anode, and a polymer-bonded porous carbon is the cathode current collector in both systems. Both cells use a Teflon-bonded acetylene black cathode structure with metallic lithium as the anode. The Li-S02 is used in a spirally wound, jelly-roll construction to increase the surface area and improve... 

It should be noted that in practical batteries such as coin cell (parallel plate configuration) or AA, C, and D (jelly-roll configuration), there is a stack pressure on the electrodes (the Li anodes are pressed by the separator), and the ratio between the solution volume and the electrode s area is usually much lower than in laboratory testing. Both factors may considerably increase the Li cycling efficiency obtained in practical cells, compared with values measured for the same electrolyte solutions in the Li half-cell testing described above. It has already been proven that stack pressure suppresses Li dendrite formation and thus improves the uniformity of Li deposition-dissolution processes [107], The low ratio between the solution volume and the electrode area in practical batteries decreases the detrimental effects of contaminants such as Lewis acids, water, etc., on Li passivation. 

Satellite viruses are those that are dependent for their own replication on some (catalytic) activity encoded in another helper virus that coinfects the host cell. The structures of three plant ssRNA satellite viruses represent some of the highest resolutions known and have been comparatively reviewed (Ban et al., 1995). The structures of satellite tobacco mosaic virus (STMV) (Larson et al., 1993a,b), satellite tobacco necrosis virus (STNV) (Jones and LUjas, 1984 Liljas et al., 1982), and satellite panicum mosaic virus (SPMV) (Ban and McPherson, 1995) have T=1 capsids composed of 60 identical copies of unembellished jelly-roll j3 barrels constructed of only 155 to 195 amino acids (Fig. la see Color Insert). What is remarkable is how little the assembly context of these domains is conserved. The same end always points toward the 5-fold axis, but the domains are rotated to different extents around the 5-fold axis. Furthermore, between STNV and the others, there is a 70° rotation of the barrel about its long axis. Contacts across the dimer interface are... 

The structure of human rhinovirus 16 (HRV16) was pursued at higher resolution (2.15 A) than most, and revealed interesting structures around the 5-fold axis (Hadfield et al., 1997). These were composed in part of residues that had been disordered in prior rhinoviral crystal structures, but had been seen in type 3 poliovirus (Filman et al, 1989). N termini of five symmetry-equivalent VPS come together to form a five-stranded parallel /3 barrel, plugging a gap between the five VPl jelly-roll domains. Each of 5 VP4 N termini contributes a / hairpin to a 10-stranded antiparallel /3 barrel closer to the virus center. In both rhino- and polioviruses VP4 is N-terminally myristoylated and these elements of structure are thought to be intimately involved with conformational transitions that occur on cell entry and uncoating. 

Figure 2 shows a schematic diagram of a complete battery (lithium-ion battery). Several cells as the one shown in Fig. 1 are wrapped together in parallel. The schematic corresponds to a cylindrical battery. The anode, separator, and cathode materials are tightly wrapped and held together to form what is called the jelly roll (see Fig. 2(a)). The jelly roll is introduced into the container or can. The container or can should be resistant to corrosion from both inside and outside, ft should also have the required mechanical strength for the specific application [4]. The containers usually have a plastic insulator for protection of the can from the external media. 

The TNF subfamily of cytokines (TNFa, TNpp, CD27, and Fas ligand). The members of this subfamily are often cell surface-associated symmetrical homotrimers of which subunits have a conformation of p-jelly rolls. The homotrimer is cone shaped, which may explain the inactivity of isolated monomers and the symmetry of three receptor subunits interacting with the TNF trimer. 

The nicad galvanic cell has cadmium anodes, hydrated nickel oxide cathodes, and KOH as the electrolyte. The electrodes are arranged In jelly-roll fashion. 

Fig. 23. Cutaway view of (a) 2016-size Eveready lithium manganese dioxide coin cell, and (b) jelly roll cylindrical lithium manganese dioxide cell (28).

The kinetics are not very sensitive to the dectrolyte so the choice is laigdy dependent on safety, toxicity, and cost. The rdativdy slow kinetics of the system has necessitated the use of thin electrodes in order to obtain sufficient current carrying capability and these cells are designed as coin cells (Fig. 23a) or as jelly rolls (Fig. 23b) with alternating anode, separator, cathode, and another separator layer. These 3-V batteries are made in sizes not used for aqueous 1.5-V cells to help prevent their insertion in circuits designed for 1.5 V. 

Fig. 9.3 Response of an 18650 cell following deliberate implantation of a metal particle on the cathode of the cell. In this experiment, a fully discharged commercial 18650 cell was removed from its can. The jelly roll was partially unwound, and a metal particle was placed rai the cathode side. The jelly roil was then placed in a suitably sized can and normally cycled. The cell experienced thermal runaway during normal charge/discharge cycling...

Figure 9.14 illustrates another use of the Safe Zone construct and the concept of a threshold power. In this assessment, simulations were performed for two otherwise identical 2.6-Ah 18650 cells having different anode materials one with MCMB 2528 (25 pm mean diameter, low surface area), and one with MCMB 628 (6 pm mean diameter, high surface area). The surface heat transfer coefficient was assumed to be 11 W/m -K. The FEA model for this particular set of simulations also accounted for the kinetics of separator shutdown. In this simulation, the short, rather than being modeled as a constant power source, is represented as a constant 25-mf2 resistance in series with the cell s 50-mQ equivalent series resistance. The total power dissipated in the cell due to the short (both i R heating in the short and Joule heating in the jelly roll) was calculated as 220 W initially. The total power dissipated in the short was then set to decrease with time based on a function that... 

Design 2 One cell with three jelly rolls connected in parallel Enhanced heat transfer between jelly rolls... 

Figure 3 represents a jelly roll construction most often used for lithium metal anode cells. The cathode can be made of manganese dioxide, carbon mono-fluoride, or iron disulfide. The use of lithium as an anode rather than zinc necessitates that the electrolyte be organic due to the extreme reactivity of lithium metal with water. 

The term prismatic cell is used for a cell which is not cylindrical in shape. Usually, it has a parallelepiped shape. We sometimes speak of flat batteries, which are in fact either flattened jelly-rolled batteries or stacked batteries, i.e. with electrodes which are stacked rather than jelly rolled. 

F ure 6.36. Jelly-roll winder for cylindrical cells (source CEA)... 

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