Lead Acid Batteries

Source: brian@ucsd.edu (Brian Kantor)

Lead-Acid batteries commonly available today can be roughly grouped into three categories by construction and intended use:

Automotive starting

Automotive starting batteries are formulated with thin pasted plates and are designed to supply high peak currents for brief periods of time whilst cranking an engine. They are not expected to be discharged to more than perhaps 75% of capacity, and are expected to be recharged immediately after discharge. If used in deep-discharge or float service they will not last long. i.e. the capacity of the battery will diminish fairly quickly. While it will still act as a battery, it will not be able to supply its rated capacity soon after being placed in the wrong kind of service.

Traction

Traction batteries are made with thick pasted plates and have very rugged separators between the plates to make the battery more immune to physical shock and vibration, and to reduce the chance of failure due to dendritic growth during recharging. These batteries are sold for use in electricforklifts, golf carts, marine trolling motors, and RV power. They are designed to be discharged nearly fully each day, and recharged each night. Because there is some tradeoff in battery life by using the pasted plate construction to keep the size and weight of the battery down, they are not used in applications where extremely long life is required. The commonly-available Deep Cycle Marine batteries are of this general type.

Stationary

Stationary batteries are made with thick solid plates. They are designed to be used as standby power, supplying minimal power and kept in a state of nearly full charge until needed. They can take deep discharge. Because of the solid plate structure, they are bigger and heavier, but their lifetime is much longer. One source suggests that 10 years is not unusual. Some photovoltaic storage batteries (for solar-powered homes and such) are of this type.


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