batteries

MacFixIt Answers is a feature in which we answer questions e-mailed in by our readers.

This week readers wrote in with questions regarding an odd apsd-related firewall error in OS X, the utility and risks of having Java Runtimes installed, options for maintaining Mountain Lion on corporate networks, and running MacBooks on a dead battery that will not charge. We welcome views from readers, so if you have any suggestions or alternative approaches to these problems, please post them in the comments!

Question: apsd firewall error in OS X MacFixIt reader Clem asks:

Don't have enough spare juice to charge all your iThings? The Exovolt Plus is a stackable battery pack with unlimited expandable capacity, according to maker Exogear.

The charger consists of a main 5,200 mAh lithium polymer battery and sub batteries that you can pile underneath it to create a battery stack. Each unit is 3.7 inches square and weighs about 5.5 ounces.

It comes with 30-pin and micro-USB connectors and can charge Apple iPhones, iPads, and iPods, as well as most smartphones and tabs.

The four LED lights on the units show how much power remains. … Read more

Buyers of the next iPhone may get a bit more juice out of the battery.

An image of the new battery sent to and posted by blog site 9to5Mac shows a capacity of 1440 mAh, a bit higher than the 1430 mAh on the iPhone 4S and the 1420 mAh on the iPhone 4, according to iPhone repair shop iFixYouri.

The battery's voltage has also received a small kick, jumping to 3.8 from the 3.7 on the iPhone 4S and iPhone 4. And the boost in capacity has led to a boost in watts-per-hour, measuring 5.45 … Read more

Editor's note:This list was originally posted on July 25 and is updated regularly.

Battery life testing is one of the last evaluations we subject tablets to at CNET Labs, but by no means is it the least valued. How long you can use your tablet is nearly as important as what it is you do while using it.

Our CNET labs testing standards ensure that all tablets, regardless of size, color, or operating system, are tested as close to equally as possible. Details on how we test tablets are included below the testing results chart. We've also … Read more

On paper, a smartphone will beat a regular phone in every single area except for one -- battery life. At least there are a few things you can do to improve your Samsung Galaxy S3's staying power and extend your fun time with your cherished new mobile.

That big, bright, show-off screen and beefy processor will have your brawny gadget wheezing like a weightlifter running the steeplechase in no time. If you play games, stream videos, or fiddle with apps on your daily commute, don't be surprised to soon witness the dispiriting sight of the battery indicator flashing … Read more

Brainiacs at Rice University today debuted a spray-on lithium ion battery that they say could be applied to nearly any surface. You read that right -- a paintable battery.

The paint contains layers, each representing a necessary component of a conventional battery -- current collectors made in part from purified single-wall carbon nanotubes, a cathode, an anode, and a polymer separator -- as described in a report published today in Nature authored by Rice graduate student Neelam Singh and her team. Spraying the painted battery is a multilayer process, but when you're done, you have a covered surface that stores energy and discharges it when needed -- that is, a battery. … Read more

A few weeks back, I wrote about how Mophie was coming out with the Juice Pack Pro, a rugged version of its extended-battery case for the iPhone 4/4S. Now iBattz has unveiled the Mojo Armor, its spin on a ultraprotective extended-battery case.

Compared with theJuice Pack Pro's integrated 2,500 mAh battery (that more than doubles the battery life of your iPhone), the iBattz includes two swappable 1700 mAh battery modules, which brings its total up to 3400 mAh. iBattz says it's, "shock, drop, dust, splash and child-proof." It comes in black, gray, or purple. … Read more

Apple's new top of the line MacBook Pro with its Retina Display packs a battery that's 23 percent larger than what can be found in the usual 15-inch MacBook Pro, and Apple seems to have passed that extra cost down to owners when the time comes to replace it.

Computerworld today notes that the price of replacing the massive battery -- which makes up more than a third of the computer's innards -- runs $199. That's up $70, or 54 percent compared to the $129 Apple currently charges to swap it out on the non-Retina 15-inch … Read more

Tired of the same old battery life drain game? A team of engineers from UC Berkeley's Algorithms, Machines, and People Laboratory has developed an app called Carat that "provides a great deal of information about how energy is being used on your phone," according to the official description.

So how does Carat work? The app runs in the background and monitors the energy consumption of various apps and processes on your smartphone, then sends that information to a data analytics Spark application running on Amazon Web Services. Usual suspects include data-hungry apps, an outdated operating system, Wi-Fi, and GPS. … Read more