Battery Charge Monitor Manual
Battery Charge Monitor shows the current charge of the battery and provides notifications if charge drops below a certain threshold.

Introduction

Battery Charge Monitor Applet
The Battery Charge Monitor applet.
The Battery Charge Monitor shows the status of any batteries in your laptop computer. The monitor can tell you the capacity remaining both visually and as a percentage, as well as offer you an estimate of the time remaining based off the current usage rate.

To Add Battery Charge Monitor to a Panel
To add Battery Charge Monitor to a panel, perform the following steps:
Right-click on the panel.
Choose Add to Panel.
Scroll down the list of items in the Add to Panel dialog, then select Battery Charge Monitor.
Click Add.
The layout of the Battery Charge Monitor applet varies depending on the size and type of panel in which the applet resides.

Power Management Backends
The battery monitor supports a number of power management backends. If it is available, the monitor will attempt to use the freedesktop.org upower interface. If it is unavailable or unsupported on your platform, it will fall back to the freedesktop.org HAL (Hardware Abstraction Layer). If that is also not available, the battery monitor will attempt direct access to the power management system
Not all power management backends are available from all vendors, and some vendors add their own additional backends for specific platforms and hardware. If the battery monitor is misreporting information from your battery see Troubleshooting.

Getting Help
If the battery monitor doesn't work for you, see these additional resources:
Troubleshooting;
MATE mailing lists

Preferences
To bring up the preferences for the monitor, right-click on the monitor in the panel and then choose Preferences

Battery Charge Monitor context (right-click) menu
Battery Charge Monitor context menu

Preferences Dialog
Preferences Dialog
Appearance 	
Compact view 	 This view shows only a single graphic in the panel, either an upright battery to indicate remaining capacity or a plug to indicate your laptop is connected to an external power source.

Compact view
Compact View
The compact view is the default view for the monitor as of MATE 2.12.
Expanded view 	 The expanded view is old look from previous versions of MATE. It has the larger graphic for the battery as well as a separate graphic to indicate what state the battery is in.

Expanded view
Expanded View
Show time/percentage 	Selecting this option will display one of two pieces of information. Show time remaining will tell you how many hours and minutes until the battery is fully discharged or recharged. Show percentage remaining will tell you the percentage charge remaining in the battery.
Notifications 	
Warn when battery charge drops to
Selecting this option will cause a warning dialog to be displayed whenever your laptop battery reaches specified value, either as a percentage remaining or a number of minutes remaining. This indicates that the amount of charge remaining in your battery is critically low. charge. You can dismiss this warning dialog yourself, otherwise it will vanish automatically when you plug your laptop into mains power.
Notify when the battery is fully recharged
Selecting this option notifies when your battery is fully recharged. If you have compiled the Battery Charge Monitor with libnotify support a non-intrusive notification will popup from the monitor on the panel.

Troubleshooting
Due to the complexities of power management and the vast differences between each of the different power management systems available, debugging errors in the battery monitor can be difficult. You will need to determine if the error exists in the battery monitor or is a bug in the information provided by your machine.
The following information may be useful for troubleshooting what is wrong with your battery monitor. It is by no means exhaustive. If you find a bug with the Battery Charge Monitor (that is not caused by bad information being reported by ACPI), please report it.

Determining the backend
If you are using the upower interface, or the Hardware Abstraction Layer (see Power Management Backends) then that will be indicated in the about dialog by placing a star next to the author of the HAL backend.

Check you're using the HAL backend
Expanded View
Other backends do not currently give indication they are being used, so you will have to guess based on your hardware. Most modern PC laptops are using ACPI as the backend. This is also the backend with the largest number of inconsistencies.

Checking the ACPI information
If you are using the ACPI backend for the Battery Charge Monitor, it is important to check that ACPI is giving you the right information. If it isn't, then you will need to look into upgrading your DSDT or something else related to ACPI.

Example ACPI output

[rupert@laptop ~]$ cat /proc/acpi/battery/BAT1/info
present:                 yes
design capacity:         41040 mWh
last full capacity:      37044 mWh
battery technology:      rechargeable
design voltage:          10800 mV
design capacity warning: 745 mWh
design capacity low:     0 mWh
capacity granularity 1:  10 mWh
capacity granularity 2:  10 mWh
model number:            G71C00056110
serial number:           0000000008
battery type:            Li-ION
OEM info:
[rupert@laptop ~]$ cat /proc/acpi/battery/BAT1/state
present:                 yes
capacity state:          ok
charging state:          discharging
present rate:            11232 mW
remaining capacity:      27140 mWh
present voltage:         11400 mV
[rupert@laptop ~]$

You can quickly calculate the percentage remaining using remaining capacity divided by last full capacity, you can calculate the time remaining by taking remaining capacity divided by present rate.

Hardware Abstraction Layer
You can check that your battery is detected by HAL using the command hal-device-manager. If your battery is not detected by HAL or the wrong information is being reported, you can attempt to disable the HAL backend by setting a GSettings key.
Select Configuration Editor from the Applications menu, under System Tools. Search for the key value OAFIID:MATE_BattstatApplet which should be located in the path /apps/panel/applets.
Assuming the path is /apps/panel/applets/applet_1. In /apps/panel/applets/applet_1/prefs add a New Key... called no_hal and set it to the boolean value of true. This will disable the usage of HAL (see Determining the backend to learn how to check this).