Navigator: getBattery() method

The getBattery() method provides information about the system's battery. It returns a battery promise, which is resolved in a BatteryManager object providing also some new events you can handle to monitor the battery status. This implements the Battery Status API; see that documentation for additional details, a guide to using the API, and sample code.

Note: Access to this feature may be controlled by the Permissions-Policy directive battery.

Syntax

getBattery()

Parameters

None.

Return value

A Promise that fulfills with a BatteryManager object which you can use to get information about the battery's state.

Exceptions

NotAllowedError DOMException: Use of this feature was blocked by a Permissions Policy.
SecurityError: The User Agent does not expose battery information to insecure contexts and this method was called from an insecure context.

Examples

This example fetches the current charging state of the battery and establishes a handler for the chargingchange event, so that the charging state is recorded whenever it changes.

let batteryIsCharging = false;

navigator.getBattery().then((battery) => {
  batteryIsCharging = battery.charging;

  battery.addEventListener("chargingchange", () => {
    batteryIsCharging = battery.charging;
  });
});

For more examples and details, see Battery Status API.

Specifications

Specification
Battery Status API # dom-navigator-getbattery