Contents at a Glance Chapter 1: Using Your Power for Good Purposes . . . . . . . . . . . . . . . .405 Adapting to AC 406 Depending on a Battery 409 Finding Hidden Batteries 414 Chapter 2: Replacing or Upgrading Your Power Source . . . . . . . . . .417 Measuring Battery Capacity and Power 417 Replacing the Battery 419 Mining Other Sources of Power 422 Adapting to Plane and Car 423 Chapter 3: Power-Management Utilities . . . . . . . . . . . . . . . . . . . . . . . .425 Using Power-Management Utilities 425 Charging up Your Battery Options 427 Advanced Power Settings 427 29 140925-pp06.qxp 4/8/08 12:49 PM Page 404 Chapter 1: Using Your Power for Good Purposes In This Chapter ߜ Learning your ACs and DCs ߜ Adopting an adapter ߜ Keeping your battery in tip-top shape Y ou know that the biggest difference between a laptop and a desktop computer is that one’s designed to be moved from place to place and the other is pretty much consigned to staying put. It’s like the difference between a bicycle and a lounge chair. (You can sit on both. . . .) The other difference — and this is more important to some users than others — is that a laptop is for using when you’re away from a standard electrical wall outlet. Some users transport their laptops from a desk in one office to a desk in another (even if it involves eight hours of flying) and never use the machine in between. All they need is an AC adapter and a wall outlet with juice. But the rest of us live the mobile life. When I leave my desk, I usually continue my work on the ferryboat (island life is such a bother), then fire up the laptop once again on an airplane, and finish my day in a hotel room checking e-mails and baseball box scores. And sometimes I run my laptop in the rental car to look up driving instructions or to make a change to a presentation. Here’s how your laptop can get its power in any one day: ✦ AC outlet. Overnight, I top off the charge in the built-in batteries using wall current. And when I’m at the gate in the airport, the second thing I look for (after I find out just how far behind my schedule my plane will be) is a wall outlet to restore as much power as possible before squeez- ing into seat 36B. Some airports are more accommodating to laptop-toting customers than others, offering special areas with desks and a whole row of AC outlets. Other places, though, make wall outlets as easy to find as a free meal in coach class. Carry a small, lightweight multi-outlet power strip in your laptop bag. If you find only a single AC outlet, and some punk is powering up his iPod, politely request he allow you to install the power strip and share. It’s a nice way to meet tech-savvy people, too. 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 405 Adapting to AC 406 ✦ Battery power. Between AC outlets, the laptop runs on its rechargeable batteries. Depending on the model, the type of battery, and the tasks you perform, most machines can run from two to four hours. ✦ Airline power sources. Some airlines offer either DC or AC outlets at some seats. ✦ Automobile power sources. Many laptops can draw DC power from out- lets within cars. You can purchase a DC inverter to produce AC power for your adapter. And finally, some new cars now offer a built-in 110-volt AC outlet. Adapting to AC The purpose of an AC adapter is to change the current that runs your light- bulbs, television set, and the air pump for your inflatable holiday tableau of a life-size Santa Claus and eight reindeer (plus Rudolph) into a different kind of power for your laptop. The current that comes from your wall outlet is relatively high-voltage AC current. The internal circuitry of your laptop requires low-voltage DC cur- rent to do its thing. Your laptop can run off the AC adapter’s power when you have it plugged in at your desk. Or it can get its juice from a battery that you can recharge by the very same AC adapter. What’s inside the AC adapter? It’s actually a relatively simple device, if you’ve got a basic understanding of electricity, electronics, and physics. Right . . . you don’t really care, do you? All you want is the juice to power up your laptop. Here are the basics: An AC adapter consists of three parts. Electrical cord A standard electrical cord attaches to an AC outlet at one end and the laptop’s AC adapter at the other. (See Figure 1-1.) Depending on where in the world you live, the end of the cord that attaches to the power source can be any of more than a dozen different designs. ✦ In the United States, Canada, Japan, much of the Caribbean and Central America, and scattered other places around the world the plug has two flat blades (like the one in Figure 1-2). Sometimes a third round ground- ing connector is there. This design is for use with current ranging from 100 to 120 volts. 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 406 Book VI Chapter 1 Using Your Power for Good Purposes Adapting to AC 407 ✦ In most of the rest of the world, wall current ranges between 220 and 240 volts, and different types of plugs are used. Some have round pins arranged in a triangular pattern, some have round mail power pins and circular female grounding points, and a large number of plugs (through- out the United Kingdom and countries influenced by the Brits over the last century) use two horizontal and one vertical blade. Courtesy of Toshiba America, Inc. Permanently attached cord At the other end of the adapter, in most designs, you’ll find a permanently attached cord. This delivers the reduced-voltage, rectified current (more about these terms in a moment) from the adapter to the laptop computer itself. The plug at the end of this cord matches the attachment point within the laptop. (See Figure 1-3.) Not all plugs are the same; partly this avoids unfor- tunate accidents where a user might try to use an improper adapter with a particular laptop. (The wrong adapter could deliver too much or too little DC voltage, or could deliver the voltage with its polarity in the wrong place. If you look very closely at the specifications on the back of any AC adapter, you see a little diagram that shows whether the positive side of the current flow comes from the core of the connector or from its outer shield.) Figure 1-2: A two-blade AC plug. Figure 1-1: The incoming power to an AC adapter comes in on a detachable and replace- able cord. 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 407 Adapting to AC 408 Courtesy of Toshiba America, Inc. Always use the AC adapter designed for your laptop’s particular brand and model, or a third-party adapter from a reputable company that specifically recommends its device for your computer. Don’t assume that two adapters that look similar will deliver the same voltage to your laptop. Adapter proper In the middle is the adapter itself. For reasons lost to the winds of time, it’s called an AC adapter; I guess it got that name because it adapts alternating current to direct current. It would have been just as understandable to me if it were called a DC adapter, since it outputs direct current to the laptop. Or you could (as some manufacturers do) call it an AC/DC adapter. In any case, this black box sits between an incoming AC power cord and an outgoing DC power cable. Inside the box are two main components: ✦ A device that transforms, or switches, the voltage. As I noted, AC wall current is generally either about 110 or 220 volts, and most laptops are looking for about 15 to 20 volts. ✦ A rectifier that changes AC to DC. Modern laptops generally use sophisticated switching power supplies that are capable of accepting AC power anywhere in the range of about 100 to 240 volts and outputting a stable and clean voltage that meets the needs of the laptop internal battery charger and the circuitry of the computer itself. They Figure 1-3: The DC end of the adapter is usually designed to make it difficult (but not impossible) to use the wrong power supply with a particular laptop. 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 408 Book VI Chapter 1 Using Your Power for Good Purposes Depending on a Battery 409 generate little heat and usually function without problem for many years. The only downside: They’re usually relatively large — about the size of a flashlight. Cheap little adapters like those you might use with a cordless telephone or an inexpensive radio may use old technology that involves spools of differ- ent lengths of copper wire that induce a reduction in voltage as they move from one to the other. They also burn off a great deal of the voltage in the form of heat. In general, they’re inefficient, bad for the planet, and present a real (although very rare) risk of causing a fire. Voltage conversion is just half of the adapter’s job. The other assignment is to rectify and filter the voltage. Think of AC current as a continuous series of rising and falling waves; the rectifier’s job is to square these up into a continuous one-way flow. The most common design uses an electronic device called a diode that squares up the power. The final step is to filter the DC current to remove any remaining fluc- tuations or wobbles related to its AC origins. Most designs employ a capaci- tor for this purpose. Think of it as a can of electrons; it allows power to settle in for a few tiny fractions of a second and then lets the calmed power flow out the other end. Depending on a Battery A battery is, by its very nature, a dynamic device. (That’s a hoot-and-holler pun for engineers; if you get the joke you just might be a geek.) What I mean is that a battery is changeable and volatile. It can accept an electrical charge and hold it for a while, and then discharge it as needed. How much of a charge? How long will it hold it without dissipating? And how long can its parcel out its electrons before it goes flat? The answer to all of these questions: It depends. ✦ On the battery’s design and size. Today’s most common design uses a technology based on Lithium Ion chemistry, sometimes called LIon. These batteries can pack a lot of power in a small, relatively lightweight cell. And then the designers can choose to use 4, 6, 9, or however many cells they feel is powerful enough but not too heavy as to turn a laptop from a lightweight contender to a heavyweight champion. ✦ On how many batteries are in your laptop. Some cases are designed to accept one battery plugged into a compartment on the underside, with a second battery installed in a multipurpose bay on the side. (The same bay can also be used for a plug-in hard drive or for a CD or DVD drive.) Once again, multiple batteries add more productive time . . . and weight. 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 409 Depending on a Battery 410 ✦ On the size and efficiency of your laptop’s major components. For example, a 17-inch, high-resolution LCD draws more power than a 12- inch, medium-resolution display; the brightness setting you choose for the LCD also affects the amount of power. The microprocessor’s type and speed also make a difference; some processors are designed to slow reduce their draw (and operate a bit slower) when the laptop is on bat- teries. In other designs the microprocessor adjusts its speed to match the tasks. Another big draw: RAM. ✦ On the tasks you’re performing. Anything the requires the spinning of a motor—like a CD, DVD, or hard disk drive—can draw down a battery fairly quickly. Playing a movie from a DVD is just about the most draining assignment you can give your laptop: it uses the drive, the LCD, and the audio subsystem. ✦ On the instructions you have given the laptop’s built-in battery- management system. If you make the proper adjustments—best suited to the particular way you use your machine—the laptop will know when it is proper to temporarily shut down the hard drive, turn off the LCD, or even go into hibernation. ✦ On how well you’ve treated your battery. Have you pampered it, kept it well fed when needed, and put it on a diet when needed? And have you kept track of its birthdays? Do you need an uninterruptible power supply (UPS) or a surge protector between your AC adapter and the wall? Well, no . . . and yes. You’ve no need for a UPS because your laptop is already running on a battery. But as far as protection from a power surge or spike: The AC adapter includes electronics that convert AC to DC and also step down the voltage from 110 to 240 volts at the wall to about 20 volts (depending on the model) at the laptop; that process puts a bit of buffering in the circuit that may protect your computer. A serious surge could fry the adapter. I recommend using a surge protector for all electronic devices. The last two of these concepts are the ones over which you have the most control. Taking it easy on your battery Two users with the identical laptop computers, the same batteries, the same operating systems, and the same set of software can vary greatly the number of hours they can use their machine away from an AC wall outlet. One might find the battery good for only a 90-minute railroad commute from Stamford, while the other may peck away for six hours between takeoff from Boston and landing in London. The key to getting the most out of your battery is to sip most gently from its cup: 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 410 Book VI Chapter 1 Using Your Power for Good Purposes Depending on a Battery 411 ✦ If you’re not using a device, turn it off. For example, switch off the WiFi transceiver when you don’t need to communicate wirelessly. (Anytime the WiFi is on, it searches for a connection, and if it finds one, uses power to negotiate an agreement to communicate.) ✦ Avoid unnecessarily using the hard drive. If your word processor is set to autosave your work every 5 minutes, consider changing that to every 10 or 15 minutes. ✦ Resist the temptation to play a music CD while you work. And under- stand that watching a movie on your laptop can burn through a battery before you get to the end of said movie. A CD or DVD drive spins con- stantly when in use and eats up a lot of power. A better solution: Convert some songs to MP3s or WAV files and store them on your hard drive; playing music from that source is much less demanding on the battery than from a CD. Even better: Get a separate music player like an iPod and leave your laptop for work. ✦ Don’t use external devices that draw power from the laptop battery. These include desktop mice and memory card readers. Some users have devices that allow them to charge an iPod or a cell phone from the com- puter battery; that’s okay, but you don’t get power for free. The power goes from the laptop to the other device. ✦ Find a comfortable environment. Extreme heat (over 80 degrees) makes your battery discharge more quickly than usual and could, in the worst case, result in a meltdown; cold temperatures make batteries slug- gish, which may affect your laptop’s ability to do those wonderful things you expect it to do. ✦ Make sure the cooling vents aren’t blocked by dirt or by objects. This includes seatback tray tables or stray pieces of paper. The fans within laptops are critical to your system’s health, but they don’t need to spin all the time. Most machines use a temperature sensor that switches the fan on when needed and off when the interior has cooled down. ✦ Turn down the light. The LCD uses a fair amount of power for its ordi- nary functions, and it also uses a backlight (essentially, a tiny fluores- cent-like bulb that illuminates the screen from behind). Most laptop power-control utilities automatically reduce backlighting when the machine runs on batteries. See if you’re comfortable manually reducing the screen brightness yourself; most machines use a function key com- mand from the keyboard for this purpose. If you’re on an airplane, try turning down the screen brightness and switching on the overhead read- ing light; try not to accidentally hit the flight-attendant call button — they’re pretty cranky these days. ✦ Reduce the load on your microprocessor. Unless you really need to run multiple programs at the same time, avoid multitasking. Close any appli- cations (including utilities that automatically load with your machine) that you don’t need open. These steps allow some processors to slow down and use less power, and may also reduce the draw by the RAM. 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 411 Depending on a Battery 412 ✦ Be aware of the varying demands of different software. Most basic office programs, including Microsoft Word and Microsoft Excel, are rea- sonably good at loading quickly and efficiently using memory. Other pro- grams, including digital image editors like Adobe Photoshop and some music players and editors, demand a lot of memory and processor effort. ✦ Understand the difference between Hibernate and Standby (or Suspend). Hibernation saves an image of your desktop, including all open files and documents, and then turns off the power to your com- puter. When you return and restore power, it loads everything the way it was without having to load the operating system and applications. By comparison, Standby or Suspend shuts down some of the machine’s components, including the LCD and sometimes the hard disk drive, but provides power to RAM so your work isn’t lost and you can quickly bring the machine back to operating status. In general, Standby is a good solution for a quick timeout — going down the aisle from seat 34C to the restroom and back — but not best if you won’t be using your machine for 20 minutes or more. Consult the maker of your machine for advice on the particular technology employed. Charging it up Happy birthday to you, happy birthday to you. You’ve been charged and recharged 400 times, and now you are through. Did you ever imagine you would read such deathless prose in a book about laptops? I could go on and on . . . but I’ll be kind and stop right now. But the point is: Batteries have a finite life. They can be recharged only a certain number of times before they die. And death can be sudden, or it can be an annoying, drawn-out process. Battery up The original design for rechargeable batteries used lead compounds; these had a number of disadvantages: Lead is heavy, it is dangerous to human health, and they weren’t the best at hold- ing and maintaining a charge for a long period of time. The next major improvement was nickel com- pounds, including nickel cadmium (often referred to as NiCad ) batteries. A similar, newer design is nickel metal hydride (NiMH), which holds a charge a bit longer. The principal disadvantage of nickel-based batteries is something called the memory effect. Over time, if a battery is regularly partially discharged and then recharged, the full capacity is reduced. 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 412 Book VI Chapter 1 Using Your Power for Good Purposes Depending on a Battery 413 Nearly all current laptops use lithium ion (LiOn) technology. These batteries have a very high energy-to-weight ratio (meaning they pack more power into a lighter package than most other technologies). An unplugged laptop holds on to its charge for a longer time, and these batteries don’t suffer from memory effect (explained in this section’s sidebar). In 2007, several laptop makers were forced to recall the LiOn batteries in their machines because of a mildly annoying problem: Some were bursting into flame or at least overheating and damaging the case and its internals. That’s not good. The total number of batteries involved was quite small, but the recall was (appropriately) huge. Always register your laptop with the maker so they can contact you in case of a recall or upgrade. According to manufacturers, a lithium-ion battery should be good for between 300 and 500 discharge and recharge cycles. And you don’t need to — and shouldn’t — drain the battery all the way to zero every time; that actu- ally shortens its life. Top off this type of battery regularly and fully discharge it about once every 25 or so uses; the value of this sort of cycle is that it helps the laptop’s built-in battery voltage “fuel gauge” properly monitor its condition. When I talk about keeping track of birthdays or the number of charges/ discharge cycles, I’m really not asking you to keep count on your desktop or the wall of your cell (or office). Just keep in mind that nothing lasts forever; if you use your laptop on batteries twice a week, that means you subject it to about 100 cycles per year. On that kind of schedule, a battery should last about three to four years. You may notice that the battery no longer delivers three or four hours of power, and that its usable time continues to shorten. Or one day, its get-up-and-go has completely gotten-up-and-went. Why? Because over time, oxidation (a change in the properties of internal metal; on a piece of iron you call it rust) increases resistance within the battery and eventually it can no longer reliably deliver its charge. Treating your battery kindly Like Queen Latifah would have sung in the movie “Chicago,” if she was talk- ing about laptops instead of the inmates on murderesses row in the Cook County Jail: When you’re good to your battery, your battery’s good to you. You can do these important things: ✦ Keep your cool. A LiOn battery holds its charge best when the tempera- ture is between 32 degrees and 77 degrees Fahrenheit (about 0 to 25 degrees Celsius). It slows down if it gets much colder, and it loses its 30 140925-bk06ch01.qxp 4/8/08 12:49 PM Page 413 . than others — is that a laptop is for using when you’re away from a standard electrical wall outlet. Some users transport their laptops from a desk in one office to a desk in another (even if it involves. components: ✦ A device that transforms, or switches, the voltage. As I noted, AC wall current is generally either about 110 or 220 volts, and most laptops are looking for about 15 to 20 volts. ✦ A. from an AC wall outlet. One might find the battery good for only a 90-minute railroad commute from Stamford, while the other may peck away for six hours between takeoff from Boston and landing