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Help Is it bad to keep the phone on a charger all day?

Zumi

Android Enthusiast
Jul 16, 2010
252
24
I work in an office and can listen to XM radio all day on the phone. Is it bad to keep it on the charger all day while I do this, to assure I have 100% battery life for when I exit the office?


Or is it better to let it dwindle down to 15% or so and then charge it while at work?
 
I would not worry about this. Li-Ion and Li-Pol batteries are durable enough to last at least 2 years being in the charger a lot or not. Even if it dies after a year or two you can buy a new one for a few dollars.

it's a little more than a few dollars but yea you can buy a new one. i do know that the droid x cuts itself off from charging when it reaches full charge, but i try not to leave it on after it's full just to be safe.
 
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I believe that most devices nowadays run directly from the charger feed once the battery is fully charged. Wall chargers have a, "check," of sorts in them that automatically stops the feed once the battery's charge reaches a certain level. At that point the phone stops fully acting on the battery so it isn't, "constantly charging," and instead just runs from the feed. This partly has to do with why you can plug the phone into a charger, without a battery in place, and still power on the phone. Charging for too long via a car charger isn't a good idea, because they don't have this feature and are actually capable of overcharging your device's battery.

I may be wrong about my initial statement, about the phone switching over from battery power to the charger's feed, but the rest I know for a fact.
 
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Charging for too long via a car charger isn't a good idea, because they don't have this feature and are actually capable of overcharging your device's battery.

not sure i believe this, at least with the X and my current car charger.

when plugged into the 120v USB adapter that came with the phone, the battery status shows 'charging (AC)'.

when plugged into a USB port on my PC, same indicator reads 'charging (USB)'. as i understand it, this means the phone is in a throttled current draw state (max 500mA), in order to be a good USB neighbor.

when plugged into the 'enercell' 12v 2xUSB vehicle adapter that i use, the indicator reads 'charging (AC)', just as when plugged into household power using the OEM adapter & cable.

how are #1 and #3 different? in both cases, the phone thinks it is on AC power and is getting ~5v/~1A power.
 
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It has nothing to do with what the phone thinks. It's the hardware that's available on the different chargers.

Vehicle chargers that work through cigarette lighters, (lol) or simple 12V feeds do not have the feature actually physically present within them that allows them to check for the battery's charge and stop sending a feed to the device. If you leave your device plugged into them for too long, it can overcharge your device. It probably needs a significant amount of time of doing this for it to actually cause any damage, but it can easily happen.
 
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hmm...again, i find it hard to believe that the OEM transformer is an more or less intelligent than the 12v transformer. sure it's not the phone that's doing the shut-off in this case?

how about this...when i plug a 90% charged phone in to the car, the charging indicator lightning bolt disappears when it tops off. this would seem to indicate that it is no longer charging. haven't tested to see whether this is true or not when on a PC USB port (ie: when the phone thinks it is not on AC), but i'd guess that it would be true there as well.

i understand that there are 'smart' battery chargers that have the intelligence built into them to monitor the battery. both my cordless drill charger and my AAA/AA/C/D household charger have this feature. but in both cases, the batteries are charged outside of whatever it is they are powering and they have no intelligence themselves.

can you please provide the evidence that allows you to state that 'the rest [you] know for a fact'? i'm not calling bullshit...just saying that your experience apparently differs from mine, and i would like to educate myself.
 
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dookie1, I obtained the information from numerous reps. at various electronic stores over time. A few of which were actually Verizon reps. at Verizon retailers. However, it's actually been a while since any of them have repeated that specific information, so things may have changed since then. The device may be recognizing that the battery is fully charged, but that doesn't necessarily mean that the charger isn't still trying to supply your device with electricity. Newer devices may have some sort of, "shut off valve," that cuts the feed to the battery. I suppose I don't know for sure anymore.

I haven't bothered to look for online documentation of this as it's never come up before in any discussion that I've taken part in, but I suppose it can't hurt to Google around a bit. I'll search some here in a little while, but if you find anything yourself, please let us know.
 
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If you're plugged into a feed coming from your computer's USB port, or an actual charger plugged into an electrical outlet, then I completely agree. It's when it comes to vehicle chargers that I tend to start worrying. I never let them charge any of my devices to 100%, just in case.

So far no issues in my case and mine gets dropped into the car dock each way of my commute. I would be more wary of knock-off car chargers (skimp on circuitry) and having the device plugged in when turning on and off the car than worry about charging the phone to 100%.
 
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The device may be recognizing that the battery is fully charged, but that doesn't necessarily mean that the charger isn't still trying to supply your device with electricity. Newer devices may have some sort of, "shut off valve," that cuts the feed to the battery. I suppose I don't know for sure anymore.

I think you're thinking of older style cadmium batteries.

Any device that uses a lithium battery has circuitry to regulate charging (and discharge) of the battery, otherwise the device would catch fire and possibly explode on the charger from an overcharge. Actually I shouldn't say any device, because the circuitry is actually in the battery pack itself. **edit - remember those Dell and Sony laptop batteries that had faulty regulatory circuitry that would catch fire??

Chargers for lithium packs are all "dumb" chargers, don't be fooled into buying a charger that claims to fast charge or condition lithium batteries because you're being sold snake oil.

Charging lithium packs is much simpler and easier than other chemistries. The charging current is much less critical and can vary, and quite honestly there is really not much difference between a $3 charger and a $50 charger, except the amount of money you are taking out of your wallet. Sure, the $50 charger might seem nicer, but is it $47 nicer? Because it's not any better for your battery.
 
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Some misinformation in this thread about charging in the car. With an Li battery, you don't have to worry about leaving it plugged in too long since it has a built in protection circuit. The main issue with them is if they overheat, and the DX does run on the warm side.. however a good Li battery has a protection circuit for temperature as well. Hopefully the batteries are designed and produced well.. don't want to see exploding batteries the way some Nokia users had in the past.
 
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Thank you, Baxter, for clearing that up for me and everyone else. I didn't realize newer batteries, chargers, or devices now work this way.

John, I wasn't trying to misinform anyone. It was old information and I didn't realize newer hardware works this way. I already pointed out that I was told this a while ago and that things may have changed. No one has told me otherwise until now. Again, sorry.

Zumi I hope your question has been answered. If you have any other questions, please ask them. ;)
 
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Thank you, Baxter, for clearing that up for me and everyone else. I didn't realize newer batteries, chargers, or devices now work this way.

John, I wasn't trying to misinform anyone. It was old information and I didn't realize newer hardware works this way. I already pointed out that I was told this a while ago and that things may have changed. No one has told me otherwise until now. Again, sorry.

Zumi I hope your question has been answered. If you have any other questions, please ask them. ;)

I think someone posted about this in the 3rd or 4th post of this thread. The good thing about a Li battery is you don't have to do a full drain then a full charge to increase battery life. Admittedly, I still do that mainly because I've been brainwashed by cad batteries.
 
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Also I should mention that if a charger doesn't supply correct voltage or amperage to the device, the battery circuitry simply won't allow it to charge.

For example, I've got a USB wall charger that came with my Kodak HD camcorder. It charges my iPod, my Droid, my wife's Blackberry but it won't charge our Samsung point and shoot camera because I think it supplies more voltage than the battery in the camera wants. The samsung charger however charges all the devices.

But, as I mention there is no need to worry about overcharge as the battery itself regulates the charge cycle. Worry more about crappy battery circuitry than chargers. (Think batteries catching fire in your pants!)

The Kodak charger BTW costs $10. Apple's iPod/iPhone charger costs $30. Why? Because it has an Apple logo on it, as they both are rated at the same voltage and amperage. No thanks, the Kodak charger isn't $20 worth of ugly.

Here's a decent resource to learn more:Battery University.
That page is specific to charging LiIon batteries, but you can get to the main page from there and check out other types as well.
 
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