always on power

[thegios]

Does it harm to have the device connected the whole day either to the power outlet or to pc with the USB cable?

[whizz]

No, it doesnt matter very much how much you charge an Li-Ion battery, though it is best to use it a bit. (just my thoughts though). Being on power all day long cant really harm the device itself.

[hanmin]

First of all, why do you want to do that?

Anyway, as whizz said, not much harm will be done to your phone, but just make sure your screen is off. Although not a common problem, there are reports that you can get burn-in (is this the right word?) for LCD screen (eg you can shadow-y image on your screen for displaying something too long).

[thegios]

cos when I am at the office I can keep my pda connected to my laptop the whole workin day

[hanmin]

If you just wnat to have your phone connected to your laptop, for whatever reason, you can disable the USB charging for your phone.

[digifan]

i think not harm

[dannyoneill]

the battery is lithium ion and leaving it on will cause no damage whatsoever. Its charging circuit will stop charge when its full anyway.

Too many people still live in the stoneage regarding batterys and think its like the old Ni-cad batts which didnt have a charging circuit and could over charge.

Leave it in all day, all night and for an entire year. It will do nothing to damage it.

[thegios]

weel I was just worried for overcharging, but if the circuit stops the charging when battery if full, it's ok then

[hanmin]

the battery is lithium ion and leaving it on will cause no damage whatsoever. Its charging circuit will stop charge when its full anyway.

Too many people still live in the stoneage regarding batterys and think its like the old Ni-cad batts which didnt have a charging circuit and could over charge.

If they are from stone age, you must be from Mars. Old Ni-Cad battery DO have circuits that prevent over charge. As a matter of fact, if you were to be using normal (slow) charger, you do not need any circuit to stop the charge. You can't charge a battery with the same voltage if the battery itself already had the same voltage. Go dig up your old physics book and read on the chaper on electricity.
Anyway, the common `battery knowhow` on NiCad batteries is that they need regular discharge to keep it on top shape. This is due to the fact that NiCad battery has the 'memory effect' (or oltage depression) that will cause it to work on their normal working voltages that they got used to (eg when it is plugged into a charger). Do a google on this if you are interested on lengthy explaination.

For the current Li-ion battery, the memory effect has been relatively 'concurred'. However, this does not mean you can have it on charger 24/7. Li-ion has its own aging process which is dependant on their normal working temperature (the cooler the better). Hence, having the battery pluged-in 24/7 is not a good thing (eg notice the relative raise in temperature of the battery while being pluged-in?). Do a google on this aging process.