Get the Most Battery Life for Your Buck How long a laptop lasts on its internal battery is one of the most important considerations for PC shoppers. Business travelers and students are often at the mercy of their computer's remaining juice, since so many conference rooms, airplanes, and classrooms are woefully short on accessible power outlets. Just a few years ago, it was necessary to buy and charge an external battery pack to get long battery life, or to insist on a machine with a removable, swappable battery. But today, even many thin ultraportables with sealed-shut chassis show impressive endurance away from an AC outlet. These recent improvements in laptop battery life are thanks to CPUs and other components that are more power-efficient than ever. (It's not just new battery technology that deserves the credit.) That's especially true of Intel's 8th and 9th Generation Core processors, which power most of the longest-lasting models currently on our list. A laptop that can last for more than eight hours without a trip to a power plug should be enough to get you through a day's work, but that's not good enough to make it to the upper echelons today. Each of the laptops and 2-in-1s we've selected lasted for more than 14 hours on our tests, which means that they can survive a full day at the office and still offer plenty of juice for your commute or for watching videos on the couch. (Maybe both.)Dell Latitude e5570 Battery In addition to being a critical specification, battery life is one of the toughest to measure. If you're watching movies all day long, you'll get far more unplugged time than someone who's editing images nonstop in Photoshop. We test battery life based on a very specific scenario: watching movies stored locally at 50 percent screen brightness and with airplane mode turned on. If you're frequently performing more CPU-intensive or graphics-hammering tasks, you'll want to shave an hour or two off of our results.Dell Latitude e7450 Battery Our top 10 list is stacked with traditional laptops and convertible designs with 360-degree display hinges. Detachable Windows tablets tend to be underrepresented, and for good reason: There's simply no room for a large battery in such a small enclosure. One notable exception is the Microsoft Surface Book 2, which includes two separate batteries, one in the tablet and one in the keyboard base. Together, they eked out an impressive 17 hours of battery life in our testing, but you'll get far less than that if you're using the tablet by itself. Want the Best Battery Life? Consider a Mac Apple's MacBook and MacBook Pro lineups have a reputation for excellent battery endurance, and Cupertino's current offerings are no exception. Most of the portable Macs we've tested recently can manage more than 14 hours away from an outlet. Which one you should choose depends on your budget, your portability needs, and your usage patterns, but you can't go wrong on the battery-life front with any Apple ultraportable. (And remember, Macs can run Windows, too.)Dell Latitude e7240 Battery Other manufacturers are more hit-and-miss. The top honors for battery life among Intel-based Windows laptops of the moment go the Dell Latitude 7400 2-in-1 (21 hours!), but many competing machines run down much more quickly. We're also seeing an emerging class of "always on" machines based on low-power Qualcomm Snapdragon processors that have outlasted most Intel-based Windows and macOS laptops we have tested. (See for example our review of the Samsung Galaxy Book2.) But know that these laptops are meant more for lightweight mobile computing with a continuous internet connection, and are far from power models meant for CPU musclework.Akku HP Compaq 8710w Ready for Our Recommendations? If you have a long plane flight, a conference, or a final-exam period ahead of you, or if you're just too busy to linger around a power outlet for long enough, any of these laptops will keep you productive throughout the day and into the evening. For a look at the wider laptop landscape, check out our very latest laptop reviews, as well as our picks for the top business notebooks and the best budget laptops.Akku HP Compaq nc2400 Does your laptop battery give out a lot sooner than it used to? Are you lucky to get an hour or two of work done before you need to start searching for an AC outlet? Sounds like it's time to think about replacing the battery. Get reader for sticker shock: laptop batteries are expensive. Prices vary from one model to another, but it's not uncommon for new power packs to sell for $100 or more. I've seen some as high as $150. When you consider that brand-new laptops now sell for as low as $300, that can be a tough pill to swallow. 1. Most laptop batteries start to fail in 1-2 years. This varies depending on your usage, of course, but the average laptop battery is good for around 400 recharges (a.k.a. cycles). After that, it starts to lose its capacity to hold a charge. That’s why the battery that once gave you, say, 3-4 hours’ worth of runtime now peters out after just 1-2 hours. And after a few years, you might be lucky to get an even an hour. 2. You can extend the life of your current battery. If you use your laptop as your primary desktop PC, you may be wasting battery cycles by leaving it plugged in all the time.Dell Latitude e7000 Battery The solution: pop the battery out until you actually need to go somewhere with your laptop. As long as the latter is plugged into an AC outlet, it doesn’t actually need the battery. Trust me on this: I’ve seen fairly new batteries that could barely last half an hour, even though the laptop rarely went anywhere. When in doubt, pop it out. 3. Investigate third-party alternatives. When you do end up needing a replacement battery, you don’t necessarily have to buy one from the laptop manufacturer--paying top dollar in the process.Akku HP Compaq nc6200 Instead, search the Web for the laptop make/model and "battery" to see if there are less-expensive third-party options. If your system is a popular model, there almost certainly will be. Also, be sure to check out Dr. Battery’s Advanced Pro Series. These replacement batteries--available for a huge range of laptop models--promise 800 recharge cycles (meaning they should last twice as long as your current battery) and come with a two-year warranty. Plus, they’re priced fairly competitively at $88 and up. By the way, you should always, always, always recycle old laptop batteries. Stores like Best Buy, Lowe’s, and Staples have bins or kiosks where you can drop them off. Okay, your turn: Have you shopped for a replacement laptop battery? If so, how much did you pay? Were you able to find any cheaper alternatives?Akku HP Compaq 8510p Note: When you purchase something after clicking links in our articles, we may earn a small commission. Read our affiliate link policy for more details.