Laptop Battery Longevity


This article was published by ComputorEdge, issue #2521, 2007-05-25, as a feature article, in both their print edition (on pages 18 and 20) and their website.

The realm of laptop batteries is typically not known for gripping news. But during the past few years, this usually dull area of the computer world, has become much more exciting — particularly for the owners of laptops whose batteries have spontaneously burst into flames, as well as other laptop users who own the same models as the aforesaid victims, and fear that they may be next.

Laptops themselves are not the only investments to burn up in the conflagrations. According to The Consumerist, a poor fellow named Dan, residing in Biddeford, Maine, lost his entire 130-year-old house, and all of its contents, to a fire apparently caused by his laptop's battery or power cord malfunctioning.

The reputations of electronics manufacturers can also start to flame out, when their batteries die — either quietly or violently. It can also be quite costly, as experienced firsthand by Sony, which had to recall 9.6 million batteries in 2006.

Life or Death

Fortunately, the odds of such a fire striking the average laptop owner are quite slim. It is much more likely that your laptop battery woes will never be anything worse than losing power during a six-hour flight whose tedium you had hoped to alleviate by watching a DVD of the classic movie The Towering Inferno. The longevity of your laptop's battery is what will determine whether or not you will see those flames (on your laptop's screen, that is, not behind it!).

The cases mentioned earlier of batteries going up in blazes, pertains not to how long the battery will typically stay juiced under normal load, but rather how much total time it will continue to provide service, before emitting its last electron, and heading for the Big Battery Bin in the sky.

We will consider both aspects of battery longevity. But in either case, the best practices will not only improve the performance of any laptop battery and the laptop overall, but will also provide additional benefits, including greater productivity for the user.

Long-Term Life

As one might imagine, a major factor in overall battery longevity, is the quality of the unit before it even rolls out the factory door. A second factor is how much power the laptop draws from the battery, over its lifetime, measured in watts. In addition, the cooler the battery runs, the better, because heat is the primary common enemy of electronic components — far more common as a cause of death than misguided hardware tweaking or misguided insects seeking warmth.

When discussing which batteries will outlast others, hardware testers and reviewers may mention the battery's manufacturer by name, but they usually identify the consumer's options by laptop maker, since each one will choose a particular battery manufacturer to supply the batteries for all units of a particular model, if not across their entire line.

We can consider the results of a study performed in late 2006, by the CRN Test Center, which examined half a dozen laptops to determine which of them draw the least amount of power and run the coolest. In their study, they included some well-known manufacturers and models, such as the Panasonic Toughbook CF-51, and far lesser-known ones, such as the Jetta International Jetbook 9700P. The fact that these two turned out to be the clear winners, demonstrates that brand-name recognition is not necessary for performance.

Some of the test results were quite remarkable. The Toughbook CF-51 was able to run off of battery power for five hours and 15 minutes, which was more than twice that of three other laptops tested. This was clearly a consequence of the model's low power usage (22 watts). Combined with the relatively low temperatures generated by the battery (a fan exhaust of 97 degrees Fahrenheit, and a battery surface of 76 degrees), the CF-51 would clearly make an excellent choice for the modern road warrior.

Far lower in brand recognition, but with equal worthiness, the Jetbook 9700P ran for almost three hours on battery power, requiring only 35 watts to do so, and staying cool under pressure (a fan exhaust of 95 degrees and the lowest battery surface temperature of all six units tested). By way of comparison, the HP Compaq nw8440 heated up its vented air to 111 degrees, and the Asus F3Jv wolfed down 42 watts.

The bottom line is, don't assume that a well-known company will provide you with the coolest running machine. Check the manufacturer's websites for the details, prior to purchasing any new laptop — or desktop, for that matter.

Short-Term Life

Time may be money, but for those computer users who value the former over the latter, it may be more important to them as to how long their laptop battery will run on a single charge, versus how long it will last before needing to be replaced altogether. For those laptop owners, and all others, it pays to learn the techniques for reducing power demands upon a machine's battery — aside from the obvious, which is to use AC power whenever it is available.

If you won't be using your laptop for a little while, but don't want to shut down your applications and then the machine itself, then put it into hibernate mode, if this feature is available. Hibernation saves the memory contents to the hard drive, and shuts the machine off, so it consumes no power. When you turn it back on, all of your open applications and their data are immediately reloaded. Hibernate mode uses less power than suspend mode, which admittedly is better than simply leaving the machine running, as far too many people do.

A significant amount of the battery's power is consumed by the laptop's moving parts, namely, the fans and hard drive. The former may be slowed down automatically if the particular laptop has a built-in throttling capability. The latter will always spin at a set speed, but you can reduce the total power consumed by reducing the required movement of the drive's actuator arm. To accomplish this, regularly defragment all of the partitions on the hard drive.

There are many other power-saving tips: Set the screen's brightness to no more than what is comfortably needed. Temporarily disable the laptop's Wi-Fi when it is not in use. Shut down applications that you do not require at the moment. Do the same for unneeded Windows services, of which there are a large number.

Disable background processes running in the system tray, which usually begin draining your battery's power as soon as Windows starts. If you are not connected to the Internet, you can temporally turn off your firewall. Most of these measures sound simple, but they all add up.

Regardless of whether your laptop's battery reaches its final hours of operation by unexpectedly reaching room temperature, or raises that temperature by igniting, you can at least put off that sad day by following the aforementioned suggestions, and doing your best to keep your laptop — and its owner — out of the news.

Copyright © 2007 Michael J. Ross. All rights reserved.

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