MobileRead Forums - View Single Post - Battery Problems? Charger Problems? Frozen KF? Try this...

jsh1120 · 04-14-2012, 12:35 PM

Folks,

I'm posting the following admittedly long-winded post in response to the numerous problems people have encountered with the KF's "battery." I've included this information in numerous posts on several forums (both for the KF and for other products). I'm posting it here in the hope that others will be able to deal with the problem without necessarily returning their KF. In many cases, it simply isn't necessary.

There are literally hundreds of Kindle Fire reviews and posts on the Amazon Kindle forum from folks who have battery and charger problems. i.e. Won't turn on, rapid battery drain, won't turn off, won't charge, etc. etc. What's interesting about this is that there are virtually identical complaints about the B&N Nook, and various smartphones including the Droid Razr Maxx (that I own) and various other smartphones. There are even reports of similar behavior on the iPad and a number of other Android tablets. So what do ALL of these devices have in common? Answer: They all have lithium ion or lithium polymer batteries and most (though not all) run the Android operating system.

Some of these problems no doubt stem from faulty charging units or bad charging ports. (The little microUSB connector on the KF is not very sturdy.) And some cases may represent faulty batteries. But given the fact that (a) many users report problems with more than one Kindle Fire and (b) a recent study of various devices returned to manufacturers for "bad batteries" found that over 90% had perfectly functioning batteries, the problem appears to be much more widespread than these factors can account for.

If you have any of the problems above, the answer is VERY likely to be that the battery monitoring software/firmware in the KF has gotten "out of sync" with the actual charge in the battery. When this happens, the device is likely to "believe" that it has sufficient charge when it doesn't or that it has no charge when it does. Either condition leads to very undesirable results.

So here are some guidelines to keep in mind and a method that will largely eliminate the problem unless you truly have a bad battery, a broken microUSB port, or charger.

Although the little battery monitor on your device looks like a fuel gauge in a car, it isn't. There is no way to "measure" the remaining charge in a lithium ion battry. It's not like a gas tank. Instead, the battery monitor measures the current voltage being supplied by the battery and compares that voltage to a "discharge profile" it has developed over time. (A battery's voltage goes down as it discharges.) If that profile is out of whack or missing data, the monitor can be completely wrong.

So the task is to keep the battery monitor discharge profile "up to date" and complete. Here's how to do it.

To avoid problems down the line when you first get your device charge it for at least four hours before using it. A device is typically shipped with about 40% charge and if the battery or the device has sat on the shelf for a couple of months, the charge may be less considerably less. However, when you first turn on the device, the battery monitoring software takes the voltage as the baseline for a full charge. That in itself will likely cause problems down the line. If you didn't charge it when you first got it, however, don't worry. You can correct the problem.

AT LEAST ONCE A MONTH go through the following procedure. (This, by the way is identical to the advice Apple provides for the iPad. It works for any lithium ion or lithium polymer powered device.)

() Turn off the KF. (If it already appears to be dead, you can skip this step.) "Turning it off" means holding the power button until the message appears asking if you want to turn it off. Say yes.

() Plug in the charge cable from Amazon and let it charge for at least four hours, preferably overnight. Pay no attention to the orange or green light. Don't turn on the KF to check on progress. LEAVE IT ALONE. Use the Amazon cable unless you are ABSOLUTELY SURE that the cable you're using supplies at least the same amperage as that cable, about 2 amps. Do NOT use cables that charge more slowly. They won't hurt your battery but they may well throw off the synchronization with the battery monitor.

() Unplug the KF and boot it. Use it normally until you see the 15% battery remaining warning. At that point, shut it down again. Do NOT allow the battery to discharge completely. It probably won't hurt the KF or the battery but it does shorten the battery life if done repeatedly. (The software should shut down the device with about 5% charge remaining but why take a chance.)

() Repeat the charging process above.

Once you've cycled the battery charge/discharge process twice, you should have a good discharge profile. From then on charge the battery on a regular basis even if you have not reached the 15% remaining level. Don't worry about "overcharging." The KF will not allow itself to be overcharged unless it's faulty. And if that happens, you'll be able to tell because it will be HOT when you take it off the charger. Just charge every night or whenever you reach the 15% charge remaining warning.

If you encounter situations where the battery appears to discharge very slowly for quite awhile and then suddenly the battery remaining indicator drops rapidly with no change in the use of the device, it's an indication of the synchronization problem. Follow the procedure above to eliminate it when it happens.

Do NOT use a low amp charger or try to charge the KF through a powered USB port on your computer. It may work; it may not. But even if it does, it's likely to contribute to the synchronization problem.

Hope this helps. And as noted, this is a process that can be used with ANY lithium battery powered device. At the very least, if you follow the procedure above and you STILL can't get your KF to perform predictably, you can be relatively sure that you have a hardware problem (battery, charger, charger port) or a process running in the background that is draining your battery.

Finally, a good source to find more information than you ever wanted to know about managing lithium ion batteries is the one below.

http://batteryuniversity.com/

04-14-2012, 12:35 PM	#1
jsh1120 Connoisseur Posts: 91 Karma: 10244 Join Date: Jan 2012 Location: Seattle, Washington USA Device: Kindle Fire	Battery Problems? Charger Problems? Frozen KF? Try this... Folks, I'm posting the following admittedly long-winded post in response to the numerous problems people have encountered with the KF's "battery." I've included this information in numerous posts on several forums (both for the KF and for other products). I'm posting it here in the hope that others will be able to deal with the problem without necessarily returning their KF. In many cases, it simply isn't necessary. There are literally hundreds of Kindle Fire reviews and posts on the Amazon Kindle forum from folks who have battery and charger problems. i.e. Won't turn on, rapid battery drain, won't turn off, won't charge, etc. etc. What's interesting about this is that there are virtually identical complaints about the B&N Nook, and various smartphones including the Droid Razr Maxx (that I own) and various other smartphones. There are even reports of similar behavior on the iPad and a number of other Android tablets. So what do ALL of these devices have in common? Answer: They all have lithium ion or lithium polymer batteries and most (though not all) run the Android operating system. Some of these problems no doubt stem from faulty charging units or bad charging ports. (The little microUSB connector on the KF is not very sturdy.) And some cases may represent faulty batteries. But given the fact that (a) many users report problems with more than one Kindle Fire and (b) a recent study of various devices returned to manufacturers for "bad batteries" found that over 90% had perfectly functioning batteries, the problem appears to be much more widespread than these factors can account for. If you have any of the problems above, the answer is VERY likely to be that the battery monitoring software/firmware in the KF has gotten "out of sync" with the actual charge in the battery. When this happens, the device is likely to "believe" that it has sufficient charge when it doesn't or that it has no charge when it does. Either condition leads to very undesirable results. So here are some guidelines to keep in mind and a method that will largely eliminate the problem unless you truly have a bad battery, a broken microUSB port, or charger. Although the little battery monitor on your device looks like a fuel gauge in a car, it isn't. There is no way to "measure" the remaining charge in a lithium ion battry. It's not like a gas tank. Instead, the battery monitor measures the current voltage being supplied by the battery and compares that voltage to a "discharge profile" it has developed over time. (A battery's voltage goes down as it discharges.) If that profile is out of whack or missing data, the monitor can be completely wrong. So the task is to keep the battery monitor discharge profile "up to date" and complete. Here's how to do it. To avoid problems down the line when you first get your device charge it for at least four hours before using it. A device is typically shipped with about 40% charge and if the battery or the device has sat on the shelf for a couple of months, the charge may be less considerably less. However, when you first turn on the device, the battery monitoring software takes the voltage as the baseline for a full charge. That in itself will likely cause problems down the line. If you didn't charge it when you first got it, however, don't worry. You can correct the problem. AT LEAST ONCE A MONTH go through the following procedure. (This, by the way is identical to the advice Apple provides for the iPad. It works for any lithium ion or lithium polymer powered device.) () Turn off the KF. (If it already appears to be dead, you can skip this step.) "Turning it off" means holding the power button until the message appears asking if you want to turn it off. Say yes. () Plug in the charge cable from Amazon and let it charge for at least four hours, preferably overnight. Pay no attention to the orange or green light. Don't turn on the KF to check on progress. LEAVE IT ALONE. Use the Amazon cable unless you are ABSOLUTELY SURE that the cable you're using supplies at least the same amperage as that cable, about 2 amps. Do NOT use cables that charge more slowly. They won't hurt your battery but they may well throw off the synchronization with the battery monitor. () Unplug the KF and boot it. Use it normally until you see the 15% battery remaining warning. At that point, shut it down again. Do NOT allow the battery to discharge completely. It probably won't hurt the KF or the battery but it does shorten the battery life if done repeatedly. (The software should shut down the device with about 5% charge remaining but why take a chance.) () Repeat the charging process above. Once you've cycled the battery charge/discharge process twice, you should have a good discharge profile. From then on charge the battery on a regular basis even if you have not reached the 15% remaining level. Don't worry about "overcharging." The KF will not allow itself to be overcharged unless it's faulty. And if that happens, you'll be able to tell because it will be HOT when you take it off the charger. Just charge every night or whenever you reach the 15% charge remaining warning. If you encounter situations where the battery appears to discharge very slowly for quite awhile and then suddenly the battery remaining indicator drops rapidly with no change in the use of the device, it's an indication of the synchronization problem. Follow the procedure above to eliminate it when it happens. Do NOT use a low amp charger or try to charge the KF through a powered USB port on your computer. It may work; it may not. But even if it does, it's likely to contribute to the synchronization problem. Hope this helps. And as noted, this is a process that can be used with ANY lithium battery powered device. At the very least, if you follow the procedure above and you STILL can't get your KF to perform predictably, you can be relatively sure that you have a hardware problem (battery, charger, charger port) or a process running in the background that is draining your battery. Finally, a good source to find more information than you ever wanted to know about managing lithium ion batteries is the one below. http://batteryuniversity.com/ Last edited by jsh1120; 04-14-2012 at 05:18 PM.