Battery grids design

Fig. 5. Lead—Acid battery grid design variations showing A lugs, B feet, C frames, and D current carrying wire for (a) rectilinear design, (b) corner lug radial, (c) center lug radial, (d) corner lug expanded metal, and (e) plastic/lead composite.

As positive grid corrosion is an important influence on the expected lifetime of standby batteries, there have been many investigations of the parameters that influence the corrosion rate. It has been established that many parameters influence grid corrosion and growth. The most important are (i) alloy composition (ii) grid design (iii) casting conditions (iv) positive active material (v) impurities that accelerate corrosion (vi) battery temperature and (vii) potential of the positive plate. 

All of the future vehicle concepts listed in Table 17.1 call upon increased electrical capacity and power compared with today s conventional automobiles. The battery requirements of these future vehicles will not be met by present lead-acid products. Adjustments to the grid design and to the surface area and conductivity of the negative active-mass, as well as the deployment of elements capable of reducing the proclivity of the cell to evolve gas (especially hydrogen) during charging, all show... 

Tubular plates offer several advantages over the flat-plate grid design, flie most important of which is that they prevent shedding of the PAM during battery service as it is held within the tubes. Thus, a lower density of the active material can be used. The typical active mass density for tubular plates is 3.6—4.0 g cm (cf. 4.0—4.3 g cm for flat-pasted plates). In addition, the enhanced porosity of the tubular plates improves the active mass utilization coefficient. 

In general, the value of the y coefficient and its uniform distribution over the surface of the grid have great effect on the power performance of a battery. Different grid designs have different y values, leading to different battery power performances. 

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