In telecommunication, the term local battery has the following meanings:

1. In telegraphy, the source of power that actuates the telegraphic station recording instruments, as distinguished from the source of power that furnishes current to the line.

2. In telephony, a system in which each telephone instrument has its own source of power, as opposed to being powered from the central office.

3. A source of local power for a telephone instrument.

Source: from Federal Standard 1037C and from MIL-STD-188