VRLA batteries disadvantages

The advantages and disadvantages of state-of-the-art AGM and gel separator technologies for VRLA batteries are given in Table 7.3. 

A further operational disadvantage of VRLA batteries is that the relative density of the electrolyte cannot be measured unless the battery is disassembled. Hence, voltage and current data are the only parameters that can be used to evaluate the condition of the batteries during operation. In addition, VRLA batteries are not available in a dry-charged condition. As a consequence, they have a shelf-life of only two years. (Note, dry-charged, flooded batteries if sealed airtight can have a shelf-life of > 5 years.)... 

The major advantages and disadvantages of VRLA batteries are listed in Table 24.1. 

TABLE 24.1 Major Advantages and Disadvantages of VRLA Batteries... 

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