While Apple previously said that the upcoming Apple Watch will require recharging every night, a 9to5Mac report revealed that the device's battery may not even last an entire day.

Apple has not yet released any official details on the expected battery life of the Apple Watch.

However, 9to5Mac was able to acquire information from sources working on the development of the device regarding specific performance targets for the battery of the Apple Watch, with actual numbers possibly falling short of such targets.

Sources say that Apple's decision to use a powerful processor and a high-quality display for the Apple Watch are contributing to a significant drain on the smartwatch's battery life. The S1 chip found inside the Apple Watch, which powers a stripped-down version of the iOS that is codenamed SkiHill, comes close to the performance of the A5 processor used in the current iPod Touch. The Retina touchscreen display, on the other hand, updates at 60 frames per second.

As of 2014, the Apple Watch was expected to last for up to about four hours for active application usage, up to 19 hours for combined active and passive usage, up to three days for standby and up to four days for sleep mode.

Sources, however, point out that the Apple Watch will likely only last for two to three days in standby or sleep mode.

While the Apple Watch is being positioned as a replacement to the traditional watch, tests on the device, wherein the clock face was continuously displayed, had the device's battery last for only three hours; no other activities were involved. It is unlikely, though, that the clock face will need to be turned on for three straight hours. When the display is turned off, the device would require much less energy.

According to sources, the battery life of the device contributed to the delay of the device's retail launch, which was originally going to be late last year.

Other smartwatches out in the market have batteries that last longer than the 19 hours that the Apple Watch is targeting. The Gear 2 smartwatch of Samsung, for example, is able to last up to three days on normal usage before requiring to be charged.

When Steve Kovach of Business Insider brought up the topic on Twitter, a lot of people responded that the Apple Watch can simply be charged midday while at work, just as most people do with the iPhones. However, this would go against what Apple is promoting the device to become.

Promotional materials for the Apple Watch state that the device is first and foremost a watch, with all the smart features only an add-on. However, as Kovach noted, if Apple is looking to have consumers replace their normal watch with the Apple Watch, the battery life should be much better than what is currently being targeted.