Battery operating conditions additives

Most commonly used separator materials for alkaline Zn/Mn02 batteries are nonwoven polymers, such as cellulose, vinyl polymers, polyolefin, and others. The separator materials must be chemically stable in concentrated KOH solutions and electrochemically stable under both oxidizing and reducing conditions in the cell. In addition to its good electronic insulation, physical strength, and porous structure, good wettability to concentrated KOH solutions is especially crucial to provide a good ionic pathway for the battery operation. 

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.)... 

Safety of the system has been a watchword for Li-Ion batteries. They have the ability to self-destruct if abused. Manufacturers are careful to ensure that the cells are safe in normal operations. In addition, cell designs incorporate features such as devices that shut off current flow when an abuse condition arises. The United Nations as well as the transportation agency in each conntry have requirements for testing to ensure a safe product for shipping. 

Your immediate supervisor, Ms. Jane Garcia, has taken you around the allyl chloride facility and told you some of the details of the plant operation. These are summarized in the Additional Background Information section. She has confirmed that the plant is currendy operating at close to the design conditions given in Table C.l and that utility consunption is within a few percent of that shown in Table C.l. In addition, she also provided you with a set of battery limit conditions. Table C.4. for the utilities, feeds, and products, which she has informed you are current and accurate. 

The DLCs can handle more than 500,000 charging/discharging cycles during a minimum operating life of 10 years with almost no change in their capacitance. Thanks to DLC, maintenance cycles and test runs are completely obviated. In addition, DLCs can be completely discharged, a condition which usually is inconceivable in conventional systems. Care must be taken to ensure short charging times in case of frequent power failures particularly in the UPS sector. In this point too, DLCs are far superior to conventional batteries. 

The battery consisted of 114, tubular-positive cells, each with a C4 capacity of 3200 Ah. In 1993, and again in 1995, the battery was capacity tested and exhibited a C4 capacity of 98.8 and 94.8%, respectively. Thus, after 15-years of service, the battery appeared to be in very good condition and was expected to provide several additional years of peak-shaving service. Its longevity was likely due to the fact that the total energy throughput was relatively low, i.e., approximately 384 cycles after 12 years of operation [13]. 

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