Deep-cycle batteries requirements

Deep-cycle batteries require good cycle life, high energy density, and low cost. The cycle life of a deep-cycle battery is usually longer than that of an SLI battery. The longer cycle life is achieved in the following manner ... 

In contrast, deep-cycle batteries are designed to provide a steady amount of current over a long period of time for power electric and/or hybrid electric vehicles. Because a deep-cycle battery acts as an engine s power function, it should be designed to be deeply discharged over and over again. To accomplish this, a deep-cycle battery uses thicker plates than a SLI battery. One of the most important requirements for deep-cycle lead-acid batteries is cycle life. 

Batteries. Case 1 includes a total of four lead-calcium deep cycle solar batteries. The four batteries are connected in series which maintains a battery bus voltage of 48 V. The battery string has a capacity of 125 Ah, which permits the batteries to store 2 hours of required system amperage based on a daily consumption of 58 kWh. 

Power wheelchairs typically incorporate 24 V d.c. energy systems. The energy for the wheelchair is provided by two, deep cycle lead-acid batteries connected in series. Either wet cell or gel cell batteries are used. Wet cell batteries also cost about one-half as much as gel cell batteries. Gel cells may be required for transport by commercial air carriers. 

Slow charge fully saturated charge takes 14 to 16 hours Must be stored in charged condition to prevent sulfation Limited cycle life repeated deep cycling reduces battery life Flooded version requires watering Transportation restrictions on the flooded type Not environmentally friendly... 

Nickel-zinc batteries may be useful for military application requiring deep cycle capability. Nickel-zinc batteries may also be employed in torpedoes, swimmer delivery vebicles, and other submersibles. Nickel-zinc has long cycle life and low cost and meets the deep cycle requirements of torpedoes and submersibles. 

For the separation of such batteries, gel construction and microfiber glass fleece separators again compete because of the deep discharge cycles, the gel construction with its lower tendency to acid stratification and to penetration shorts has advantages for the required power peaks, microfiber glass fleece construction would be the preferred solution. The work on reduction of premature capacity loss with lead-calcium alloys has shown that considerable pressure (e.g., 1 bar) on the positive electrode is able to achieve a significantly better cycle life [31-36], Pressure on the electrodes produces counter pressure on the separators, which is not unproblematic for both separation systems. New separator developments have been presented with... 

Flaving had over 150 years of technical development behind them, lead-acid batteries can be custom-tailored to specific applications, such as those requiring deep discharge cycles (e.g., where the batteries are used as the sole power source for electrical equipment) and for battery backup uses such as in large uninterruptible power supply systems in data centers. Moreover, lead-acid cells not only have low internal resistance but also experience no memory effect as do some more exotic cell designs, such as NiCads. This enables these cells to produce enormous currents and have a moderately long, predictable life.1... 

In a typical LEO cycle, the ability for an energy storage system to deliver deep discharges over thousands of cycles allows a spacecraft manufacturer to size the capacity of the battery based on the Wh required per discharge cycle provide for deep discharge... 

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