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Figure 15-11
Rectifier method of battery
charging: (A) A-C voltage wave
shape, (B) rectified A-C voltage wave
shape, (C) rectifier voltage impressed on
battery voltage (solid line shows combination
output voltage wave shape with ripples
greatly exaggerated).

| Cell Temperatures |

| Cell temperatures should not much exceed 45°C or 110°F. The effect of high temperatures is to shorten the life of the wood separators installed between the positive and negative plates of some cells. There is always a tendency for wood, especially when in contact with sulphuric acid, to become carbonized, and this tendency is greatly increased at high temperatures. Internal losses are also increased. |

| At low temperatures, the voltage and capacity of a battery are temporarily reduced because of the greater internal resistance at such temperatures. At 20°F, the internal resistance is about double what it is at 80°F. |

| Gases |

| The hydrogen and oxygen given off during the charging of a battery form a gaseous combination that will explode violently if ignited. For this reason, battery housings should be well ventilated, and the presence of any exposed flame, spark, lighted matches, or cigarettes must never be permitted. |

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