General term for an electrochemical cell or battery. Covers both single cells and multi-cell batteries.
リモコンの電池が切れた。
The remote control's battery died.
This clock uses AA batteries.
I put new batteries into the remote control.
I had the watch's battery replaced.
The toy's battery died.
I charge my phone's battery every night.
This camera's battery lasts a long time.
rechargeable battery
photovoltaic cell; solar cell; photocell