By Graham K. Rogers

For users of Apple notebook computers, the battery is a critical component. An older MacBook Pro I had used to eat a battery a year and even when I changed it, the power consumption was fairly quick. It was similar with my last MacBook Pro, although batteries did not need replacing quite so often. In comparison, my recent acquisition of a 13" MacBook Pro with Retina display uses far less power; but finding information about the battery in a Mac is not always simple. I found an app that helps, although it does have some idiosyncrasies.

Background

More information about the state of the battery can be found in System Information. This may either be opened directly from the Applications > Utilities folder; by using Launchpad; or by clicking on the Apple menu and About this Mac, then "More Info. . ." A panel opens with some information on the Mac and at the bottom of this panel is a button marked, System Report which shows a wealth of detail about the Mac and its condition.

The problem here, is the full content and its complexity. To find information on the battery, requires a user to look at the side panel and highlight the Power section, which is in Hardware. At the top of the main panel we will find a section marked, "Battery Information". That is not the whole picture as, lower down the page, in System Power Settings, is another set of data about the battery. There is more information than most users will want, if they can find it.

Some users may have installed the iStat Pro widget, but this also has a minimum of battery information (4 lines), so only provides a general overview.

A free utility that can be downloaded from the Mac App Store - Battery Health - collects all of the useful information that users will need about the battery in the Mac and displays it in a easy to read panel. There are, however, a few oddities that had me wondering about the value of the app to begin with. As I used it, I was able to dismiss this in the light of its value to me.

Installation and Idiosyncrasies

The app was not shown in the Dock (but see below); nor was it shown in the Finder's Recent Items list. It was not until I had been using the app for a while that I saw an icon in the menubar and this (or the alternative Dock item) makes control much easier. Initially, when I began to use another application, the Battery Health display disappeared entirely. It reappeared when I clicked on the icon in Launchpad (and the menubar icon when I finally found it), but this was not making things easy.

To check this I had several other apps open (and overlapping) on the desktop, along with the Battery Health app. The moment I clicked on any of the other windows, the app was gone. It appeared to be a background app in more ways than one.

These initial impressions were dealt with by an "Ah ha" moment, while I was running through the app displays (see below).

Displays and Use

The information shown is also more accurate than the normal readouts available to the user. For example, while the menubar icon showed a fixed 22%, I watched while the charge dropped from 22.3% to 21.5%. At this time, the display bar was colored yellow, while a battery health bar was green and showing 90.4%: and that after just one month (Note to self - buy AppleCare).

The app displays 4 sections in a floating window:

• Battery Charge
• Battery Health
• Time Remaining
• Details
  • Cycles
  • Age
  • Temperature
  • Power Usage - with a readout of usage in mAh (milli-Ampere-hours) at the bottom

There is no doubt that the battery in this new 13" MacBook Pro with Retina display allows me to work for much longer between charges and the section of the panel on Time Remaining gave me several data readouts. Even with 20% remaining, there was still a lot I could do before the Mac would sleep.

At the bottom of the panel was a button marked Tips. When pressed, the display rotated and a text panel was shown with 10 suggestions for battery health, including (number 10) how to calibrate a battery. The button at the bottom of the text panel is now marked Stats and pressing this returns the user to the main display.

To the right of the Tips button is a gearwheel icon. This reveals a menu. In the list is an item marked, "Switch to Dock" This places the icon in the Dock and this may be more useful for some users. I took the opportunity to make this a permanent Dock item so it is easier to access the utility at all times. I found that the Switch to Dock item made the panel visible when other windows were in use.

When I connected the power supply (at 15.4%) there were a number of changes, all of which are sensible. Items in Time Remaining were all shown as "n/a - charging"; in details, "Power Usage" and "mAh Usage: were marked, "Is Charging"; and the graph stopped displaying data (although it was still moving).

While the power supply was connected, the current charge kept increasing and once this passed 20% the bar changed back to yellow from red. when I next checked, the power was over 70% and the bar was green.

Comments

While my current MacBook Pro, is frugal, users of some older machines (or with older batteries) will be able to keep a closer check on the way power is being used.

As a free app, this is a no-brainer. Battery Health uses around 1% of CPU when active and about 65 MB of RAM (out of 16 GB available).

Graham K. Rogers teaches at the Faculty of Engineering, Mahidol University in Thailand where he is also Assistant Dean. He wrote in the Bangkok Post, Database supplement on IT subjects. For the last seven years of Database he wrote a column on Apple and Macs.