[NA]Device Chargers[NA]

[Let'sgoflying!]

(device = cell phone, ipod, kindle book, pda, etc)


T or F:

Leaving a device plugged in to charge for an excessively long time will damage the battery or reduce its lifespan. (Say answer for each battery type or charger type if necessary)

Leaving a charger plugged into the wall without a device attached will damage the charger or reduce its lifespan.

 

[wsuffa]

(device = cell phone, ipod, kindle book, pda, etc)


T or F:

Leaving a device plugged in to charge for an excessively long time will damage the battery or reduce its lifespan. (Say answer for each battery type or charger type if necessary)

Leaving a charger plugged into the wall without a device attached will damage the charger or reduce its lifespan.

Dave, it depends on the specific manufacturer and model number. Generally it won't damage the battery, but it may or may not reduce life. For some types of battery (ni-cad for certain), you periodically need to discharge the battery fully to avoid memory effect. My HP computer has enough of a brain to stop charging when the battery is full - I've had a cellphone where the battery floats across the charger, which can reduce battery life. Again, the specific make and model will determine whether it's a problem.

As for leaving a charger (wall-wart) plugged in all the time, it will suck electricity. Some folks call 'em electric vampires. If they run warm, it can reduce life of the charger... and in rare cases, I've seen 'em melt. Having said all that, I've left most of mine plugged in most of the time.

 

[gismo]

Dave, it depends on the specific manufacturer and model number. Generally it won't damage the battery, but it may or may not reduce life. For some types of battery (ni-cad for certain), you periodically need to discharge the battery fully to avoid memory effect. My HP computer has enough of a brain to stop charging when the battery is full - I've had a cellphone where the battery floats across the charger, which can reduce battery life. Again, the specific make and model will determine whether it's a problem.

I agree with most of that (the memory effect of Nicads has been both greatly exaggerated and improved significantly in recent years). In any case, most cellphone chargers are actually in the cellphone with the gadget we think of as the "charger" actually being a power supply. IOW control of the charging process is entirely inside the phone and in virtually every handheld cellphone ever made, the internal charger will not overcharge the battery and can be left connected indefinitely without any harm to the battery.

Other devices may use less sophisticated charging schemes, often involving very imprecise control of the process. A common approach is to limit charge current by the impedance of the wall wart and control the charge time manually (by instructing the user to disconnect the charger after 24 hours). This setup will shorten battery life if left connected for too long.

As for leaving a charger (wall-wart) plugged in all the time, it will suck electricity. Some folks call 'em electric vampires. If they run warm, it can reduce life of the charger... and in rare cases, I've seen 'em melt. Having said all that, I've left most of mine plugged in most of the time.

The wasted (idle) power for most plug-in chargers amounts to a few watts or about a penny per day. The greatest risk to them if left plugged in is the increased chance of a transient (surge) damaging them.

 

[Let'sgoflying!]

bottom line is, "unplug when charged"?

 

[ScottM]

I agree with most of that (the memory effect of Nicads has been both greatly exaggerated and improved significantly in recent years). In any case, most cellphone chargers are actually in the cellphone with the gadget we think of as the "charger" actually being a power supply. IOW control of the charging process is entirely inside the phone and in virtually every handheld cellphone ever made, the internal charger will not overcharge the battery and can be left connected indefinitely without any harm to the battery.

Other devices may use less sophisticated charging schemes, often involving very imprecise control of the process. A common approach is to limit charge current by the impedance of the wall wart and control the charge time manually (by instructing the user to disconnect the charger after 24 hours). This setup will shorten battery life if left connected for too long.



The wasted (idle) power for most plug-in chargers amounts to a few watts or about a penny per day. The greatest risk to them if left plugged in is the increased chance of a transient (surge) damaging them.

Very true Lance. Devices that have LiION batteries in them have smart chargers in them to stop damage to the LiION cells. After the charge has been acheived they do a 'maintenance' pulsing of the battery to keep it topped off without damaging it. For most name brand devices with their real battery packs, not the aftermarket cheapies, leaving the unit plugged in will do no harm.

 

[mikea]

bottom line is, "unplug when charged"?

That's teh best practice.

If you can run it down to dead, dead, dead and then charge overnight or less and remove the charger from the wall.

READ THE MANUAL for the device. Some will tell you to limit charging to 4-6 hours!

I read a review for my Shark sweeper that said - when there were complaints about low run time - the charger is so big it can cook the battery if you leave it connected.

Some like my Black and Decker Hand Vac are designed to be powered all the time as the charger is built in to the housing. (Yeah, I own like 8 different kinds of vacuums. I even use them once in a while. I just bought a new one I like a lot. )