How to obtain Tag's battery level?

[color=#000000][size=medium][font=UICTFontTextStyleBody]Hi,[/font][/size][/color]
[color=#000000][size=medium][font=UICTFontTextStyleBody]Is it possible to acquire Tag battery level through Listener or Gateway?[/font][/size][/color]
[color=#000000][size=medium][font=UICTFontTextStyleBody]Best Regards.[/font][/size][/color]
[color=#000000][size=medium][font=UICTFontTextStyleBody]DongJiang[/font][/size][/color]