It seems Apple will only be releasing one new iPhone 6 this year. According to a Taiwanese news outlet, Apple’s rumored 5.5-inch iPhone 6 has been delayed until 2015 due to issues with finding an appropriate battery for its thin design.

The Internet is awash with rumors about Apple’s forthcoming devices, the iWatch, iPad Air 2 and the iPhone 6. The latter has been rumored to be released in two versions this year. Ming-Chi Kuo of KGI Securities gave a timeline for the release, positing that a 4.7-inch iPhone 6 will launch in September, while the larger 5.5-inch iPhone 6 is delayed and will launch in the fourth quarter.

However, Kuo originally stated that issues with the display were causing delays on the 5.5-inch iPhone 6. Tawain’s Commercial Times (via GforGames) reports that issues with the battery are delaying the 5.5-inch iPhone 6, which they call the iPhone Air, even further, delaying it to next year. With Apple’s release schedule that could mean that consumers won’t get a look at the larger iPhone Air until potentially third quarter 2015.

According to the Commercial Times, Apple’s suppliers are having a harder time producing batteries to the designed thinness for the large iPhone. Traditional smartphone batteries range anywhere from 2.8mm to 3mm in thickness. But Apple’s larger iPhone 6 requires a battery that is less than 2mm thick.

The report does not mention the 4.7-inch iPhone 6 though, meaning that customers will most likely see this version, or something close to it, in the fall. While we know that Apple will be producing a new iPhone this year, as per usual, the tech giant has been quiet on what it may look like. However, rumors and possible leaked photos of the iPhone 6 seem to confirm the larger screen.

In mid-April, pictures of a screen resembling a possible 4.7-inch iPhone 6 front glass panel emerged, rumored to come from one of Apple’s Chinese manufacturers. The glass panel has all of the signs of being an Apple display screen, including a camera and proximity sensor cutout. Additionally, the bezel is thinner on the sides, which aligns with recent rumors. To increase the size of the screen without increasing the width of the phone, Apple will need to reduce the bezel on the sides.

Additional rumors indicate an upgraded processor, the A8, and a possibly optical stabilized camera module. The iPhone 6 is also speculated to launch with Apple’s next version of its mobile operating system, iOS 8, which will include a bevy of health-related applications in a new group app supposedly called Healthbook.