Accumulator (energy)

An accumulator is an apparatus by means of which energy can be stored, such as a  rechargeable battery or a hydraulic accumulator. Such devices may be electrical,  fluidic or mechanical and are sometimes used to convert a small continuous power source into a short surge of energy or vice versa. Other examples of accumulators include capacitors, compulsators, wave energy machines, pumped-storage hydroelectric plants. The most common type of accumulator is the lead-acid battery.
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