1. the production by means of electric energy of chemical reactions that when allowed to reverse themselves generate electricity again without serious loss
2. Storage is frequently used to describe the devices and data connected to the computer through input/output (I/O) operations -- that is, hard disk and tape systems and other forms of storage that don't include computer memory and other in-computer storage. For the enterprise, the options for this kind of storage are of a much greater variety and expense than those related to memory.
https://www.merriam-webster.com/dictionary/storage (1.); http://searchstorage.techtarget.com/definition/storage (2.)