6. You can safely leave devices charging.
Modern mobile device batteries contain circuits that control the flow of power, so it is safe to leave them plugged in and charging for long periods. When the battery is fully charged, the battery management controller will regulate the flow of power to keep the battery topped up, but won’t overcharge it. Which is a good thing, as an overcharged Li-Ion battery could explode.
7. It is good for your batteries to occasionally completely run them down and fully recharge them.
Modern Lithium Ion batteries don't suffer from the memory effect problem that plagued their older nickel-cadmium cousins, so you can safely recharge your device even if the battery hasn't completely run down. Nevertheless, manufacturers recommend running the battery down and recharging it fully at least one a month to maximize the battery's life, as this helps keep the battery conditioned and helps preserve its chemistry.
8. Treat your batteries with respect.
If you treat them well, your devices' batteries will repay you with years of service. But if you don’t treat them well, they won’t respond well—which is a problem because the insides of batteries are dangerous places. It may help to think of batteries as small chemical fires waiting to happen: You should always carry them in the device or in a case (if you're carrying a spare). Never poke, puncture, or otherwise mistreat them.
9. Replace (and recycle) your batteries every two years or so.
As batteries get older, their ability to retain a charge diminishes, and consequently your device's battery life gets shorter. This gradual but inevitable process reflects chemical changes inside the battery. Most batteries should be good for a couple of years, though: Apple asserts that the battery in an iPad will hold 80 percent of its maximum charge after 1000 charges, and other manufacturers make similar claims.
When you do replace them, recycle the old batteries at a hardware store or other designated rechargeable battery drop-off. The Call2Recycle website will help you find a recycling station in your area. Don't discard any recyclable battery into the trash, as its ingredients are quite poisonous and potentially combustible.
10. You can diagnose a USB power problem in a few simple steps.
If you're trying to use a USB port to charge a device, but it isn't working, you can find tools in Windows that may improve the situation. Unfortunately those tools are buried rather deep in the system. To get to them, go to Control Panel > Device Manager, and select Devices by Connection from the View menu. Click the top item on the list (which should be the name of your PC), and press the * key. This will open a list of all the devices connected to your system. Scroll down until you find one called 'Generic USB Hub'. This is your computer's built-in USB hub, which connects the USB ports in the case. You may have more than one such hub, depending on your system. Right-click Generic USB Hub and select Properties. In the Generic USB Hub Properties window click the Power tab, and you'll see a list of connected USB devices, together with the amount of power that each one is drawing. This information can help you determine whether the device will charge quickly (if the number is, say, 500mAH or above) or relatively slowly (if the number is less than 500mAh). When I checked this list on my computer, I found that my cell phone was drawing just 96mA. As a result, even though the phone reported that it was charging, it was receiving only a trickle of power, and would probably never have charged fully.
This story, "10 tips to keep your mobile devices charged and happy" was originally published by TechHive.