Comparative Evaluation of Starter Battery Separators

The individual starter battery separator systems have been described here they are evaluated comparatively. There are no standards for evaluating separators Therefore the comparison will be concentrated primarily on the effects on the performance of the starter battery, with other decisive criteria such as cost structure and effects on productivity indicated. 

Cold crank performance, battery life expectancy, and freedom from maintenance are generally co-affected by the separators, whereas ampere-hour capacity remains largely unaffected at a given separator thickness. The properties of the different leaf and pocket separators are compared in Table 10. These typical separator properties (lines 1-4) are reflected in the electrical results of battery tests (lines 5-8). The data presented here are based on the 12 V starter battery standard DIN 43 539-02 tests based on other standards lead to similar results. 

The cold crank voltage is directly affected by the separator electrical resistance (cf. Sec. 9.1.2.3 Fig. 5), but to a 

The life expectancy of a starter battery, according to DIN 43 539-02, is not affected by the separator. Experience has 

Polyethylene pocket separators Sintered PVC separators Cellulosic separators Cellulosic/ glass mix separators Glass fiber leaf separators 

The life expectancy of a starter battery, according to DIN 43 5 39-02, is not affected by the separator. Experience has shown that all batteries with modern standard separators in cycle life tests not only last the required 5 weeks of cycling, but mostly 10 weeks or more. The cause of failure is typically positive grid corrosion - in good agreement with practice [49]. This fact supports this standard, which is supposed to reflect reality, but on an accelerated time scale. 

Surprisingly the water consumption of a starter battery, provided that it contains antimonial alloys, is affected by the separator. Some cellulosic separators as well 

The above comparative evaluation of starter battery separators refers to moderate ambient temperatures the standard battery tests are performed at 40 or 50 °C. What happens, however, on going to significantly higher temperatures, such as 60 or 75 °C This question caimot be answered without considering the alloys used batteries with antimonial alloys show a water consumption that rises steeply with increasing temperature [40], leaving as the only possibilities for such applications either the hybrid construction, that is, positive electrode with low-antimony alloy, negative electrode lead-calcium, or even both electrodes lead-calcium. 

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Table 10. Comparative evaluation of starter battery separators...

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