First to have little a bit electrical knowledge about the battery then the other aspects should be discussed. It is 3.75 V and 24.8watt-hour (6.4 amps) runs the device for 10 hours of normal usage as advertised by the manufacturers. Many people connecting the apple iPad battery to laptops and expecting to recharge faster as the laptop cannot provide a high voltage for a faster recharge though this action may also cause little bit faster rate of losing charge and damaging battery life. Thus do not try to recharge your iPad through laptops other than some serious cases when really want your iPad recharged. Recharging your apple iPad battery from desktop computer is an OK source though it does not have any side effects on the battery or iPad but the rate of recharging the battery is still slower than plugging into some socket with a 10watt adapter. The rate of losing charge when recharged with desktop or tower computers is normal as compared to laptops and plugging into socket. Some past model computers are not eligible to charge the iPad battery as they are not designed to support that power needed by an iPad. Most preferred recharging method is through plugging the iPad connector into a 10watt adapter and plug in the adapter to the mentioned voltage of power as directed 110volt or 240volts. As experiments with an apple iPad battery have shown that when recharged with normal power gives up to 11 or 12 hours of usage even more than the advertised limit by manufacturers.

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