Does this shorten an iPhones battery life

[Laidbackal]

Does using your iPhone while it is fully charged while still plugged in. And playing games or browsing the web does this shorten the battery life because the phone is still plugged in just wondering.

 

[scaredpoet]

It shouldn't so long as you let your battery run down at least once a month, then charge it back up all the way.

 

[wordoflife]

Nope it's fine. Assuming you actually use it as a phone too (in other words, remove it from the charger at some point), it's getting enough discharges/recharges to keep the battery healthy.

 

[thewitt]

Lithium ion batteries do not have memory like Ni cad batteries. They do have a fixed number of cycles in them however, and are actually stressed more when you allow them to fully discharge before charging. This full discharge-charge actually will shorten the life of you battery compared to charging at 75% - though once a month is fine.

 

[Stealthipad]

The cord from the charger will wear out first!

 

[S.B.G]

Wirelessly posted (iPhone 4S: Mozilla/5.0 (iPhone; CPU iPhone OS 5_0_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9A405 Safari/7534.48.3)

Lithium ion batteries do not have memory like Ni cad batteries. They do have a fixed number of cycles in them however, and are actually stressed more when you allow them to fully discharge before charging. This full discharge-charge actually will shorten the life of you battery compared to charging at 75% - though once a month is fine.

This is true and to add to it:

Devices with lithium-ion batteries are designed to stop charging at 100%. This is why sometimes you'll see your percentage at less than 100% though it's still on the charger.

1 of 2 things are happening. The device will charge to 100% and stop, but if the phone is on the charger long enough and being used, it will drain the battery until it gets somewhere around 94% before the charger starts up again. Trickle charging lithium-ion batteries will work to destroy them, and these devices don't do that, which is why you see the dip in percentage.

The other thing is that one of the cells might not be matched closely with the other cells in the battery and could be off by a few micro-volts. When charging, the device will only charge the battery to the maximum capacity of the first cell that reaches 100%. That would be the cell that didn't get matched properly at the factory and can sometimes be corrected by letting the battery drain all the way down once in a while.

Lithium-ion battery's like to be charged and letting them go too far down, too often will lessen their lifespan.

From Battery University:

Overcharging Lithium-ion

Lithium-ion operates safely within the designated operating voltages; however, the battery becomes unstable if inadvertently charged to a higher than specified voltage. Prolonged charging above 4.30V forms plating of metallic lithium on the anode, while the cathode material becomes an oxidizing agent, loses stability and produces carbon dioxide (CO2). The cell pressure rises, and if charging is allowed to continue the current interrupt device (CID) responsible for cell safety disconnects the current at 1,380kPa (200psi).
Should the pressure rise further, a safety membrane bursts open at 3,450kPa (500psi) and the cell might eventually vent with flame. The thermal runaway moves lower when the battery is fully charged; for Li-cobalt this threshold is between 130–150C°C (266–302°F), nickel-manganese-cobalt (NMC) is 170–180°C (338–356°F), and manganese is 250°C (482°F). Li-phosphate enjoys similar and better temperature stabilities than manganese.
Lithium-ion is not the only battery that is a safety hazard if overcharged. Lead- and nickel-based batteries are also known to melt down and cause fire if improperly handled. Nickel-based batteries have also been recalled for safety concerns. Properly designed charging equipment is paramount for all battery systems.

Over-discharging Lithium-ion

Li-ion should never be discharged too low, and there are several safeguards to prevent this from happening. The equipment cuts off when the battery discharges to about 3.0V/cell, stopping the current flow. If the discharge continues to about 2.70V/cell or lower, the battery’s protection circuit puts the battery into a sleep mode. This renders the pack unserviceable and a recharge with most chargers is not possible. To prevent a battery from falling asleep, apply a partial charge before a long storage period.
Battery manufacturers ship batteries with a 40 percent charge. The low charge state reduces aging-related stress while allowing some self-discharge during storage. To minimize the current flow for the protection circuit before the battery is sold, advanced Li-ion packs feature a sleep mode that disables the protection circuit until activated by a brief charge or discharge. Once engaged, the battery remains operational and the on state can no longer be switched back to the standby mode.
Do not recharge lithium-ion if a cell has stayed at or below 1.5V for more than a week. Copper shunts may have formed inside the cells that can lead to a partial or total electrical short. If recharged, the cells might become unstable, causing excessive heat or showing other anomalies. Li-ion packs that have been under stress are more sensitive to mechanical abuse, such as vibration, dropping and exposure to heat.

 

[bjb.butler]

1 of 2 things are happening. The device will charge to 100% and stop, but if the phone is on the charger long enough and being used, it will drain the battery until it gets somewhere around 94% before the charger starts up again. Trickle charging lithium-ion batteries will work to destroy them, and these devices don't do that, which is why you see the dip in percentage.

That's not what Apple seems to think...

Rechargeable lithium-based technology currently provides the best performance for your Apple notebook computer, iPod, iPhone, or iPad. You can also find this standard battery technology in many other devices. Apple batteries share the characteristics common to lithium-based technology in other devices. Like other rechargeable batteries, these batteries may eventually require replacement.

Most lithium-ion polymer batteries use a fast charge to charge your device to 80% battery capacity, then switch to trickle charging. That’s about two hours of charge time to power an iPod to 80% capacity, then another two hours to fully charge it, if you are not using the iPod while charging. You can charge all lithium-ion batteries a large but finite number of times, as defined by charge cycle.

http://www.apple.com/batteries/

 

[S.B.G]

That's not what Apple seems to think...



http://www.apple.com/batteries/

That's correct, but not a contradiction. The fast charge goes to 80% then trickle charges from there the remaining 20%. Once it reaches 100% it stops the trickle charge until it drains (while on the charger) back down to 94%, or thereabouts and then begins charging again. Ni-Cad and other types of batteries will continue to trickle charge at 100% in order to keep them there. Doing that to a lithium-ion will ruin it.