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navigator.getBattery

Obsolete
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

The getBattery() method provides information about the system's battery, 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.

Syntax

var batteryPromise = navigator.getBattery();

Return value

A Promise which, when resolved, calls its fulfillment handler with a single parameter: a BatteryManager object which you can use to get information about the battery's state.

Example

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(function(battery) {
  batteryIsCharging = battery.charging;

  battery.addEventListener('chargingchange', function() {
    batteryIsCharging = battery.charging;
  });
});

For more examples and details, see Battery Status API.

Specifications

Specification	Status	Comment
Battery Status API The definition of 'Navigator.getBattery()' in that specification.	Candidate Recommendation	Initial definition

Browser compatibility

Feature	Chrome	Firefox (Gecko)	Internet Explorer	Opera	Safari
Basic support	39	10 (10) moz 16 (16)^[1] 43 (43)^[2] 52 (52)^[3]	No support	25	No support

Feature	Android Webview	Chrome for Android	Firefox Mobile (Gecko)	IE Mobile	Opera Mobile	Safari Mobile
Basic support	40	42	10.0 (10) moz 16.0 (16)^[1] 43.0 (43)^[2] 50.0 (50)^[3]	No support	25	No support

[1] Disabled by default in Firefox 10.0, but can be enabled setting the preference dom.battery.enabled to true. Starting with Firefox 11.0, mozBattery is enabled by default. The Battery API is currently supported on Android, Windows, and Linux with UPower installed. Support for the Battery API on Mac OS X is available starting with Gecko 18.0 (Firefox 18.0 / Thunderbird 18.0 / SeaMonkey 2.15). Firefox also provided support for the deprecated navigator.battery until Firefox 50.

[2] The new promise-based syntax for Navigator.getBattery() is supported from Firefox 43 onwards.