Each aircraft has enough power in the backup batteries to facilitate a safe landing.

Only the craft's life supports, which drew on a backup battery, continued to function.

The backup battery for the Series 3a is a CR1620.

He said each siren would be equipped with four backup batteries.

The clock has a backup battery and keeps talking when you unplug it.

With power out, he wasn't going to waste time seeing if the backup battery would open the doors.

"That alarm must have sent a signal when we killed the power and it switched over to the backup batteries."

"They've got this place wired and the alarm's running on backup batteries."

A special backup battery would ensure that the memory was not lost while the main batteries were changed.

"We're going to have to use a backup battery to keep the computer running," he said.