The iPhone 16 Pro Max is rumored to feature numerous battery enhancements like a higher energy density cell and a metal battery casing for the first time in an iPhone, reports esteemed analyst Ming-Chi Kuo.

In a new post on Medium today, Kuo says that the battery of the iPhone 16 Pro Max will feature an increased energy density, allowing it to pack more battery capacity within the same physical dimensions. Apple could also keep the same battery capacity as the iPhone 15 Pro Max but in a smaller design, making space for other components inside the iPhone.

A higher energy density has the downside of generating more heat over the battery. To mitigate overheating, Apple plans to incorporate a stainless steel battery case for the iPhone 16 Pro Max instead of the traditional black foil casing found on every iPhone to date. Kuo adds that this year, the metal casing will be limited to the iPhone 16 Pro Max. Apple is opting for stainless steel over aluminum due to the former’s corrosion resistance and general sturdiness, providing better physical protection for the battery.

If all goes well with the new battery design, Kuo states that Apple will expand the new battery to all models of the iPhone 17 lineup next year. This will be major favorable to Sunway, Apple’s chosen supplier for the metal battery casing for the iPhone 16 Pro Max. Sunway could see its revenue double in 2025 if the metal battery’s adoption plan for the iPhone 17 lineup goes as planned.

A rumor from last year was the first to claim that Apple is looking at metal battery cases for the iPhone 16 lineup. While that rumor claimed to show a prototype metal battery for the smaller iPhone 16 Pro, Kuo’s report today claims that the new battery design will only be limited to the blogger iPhone 16 Pro Max. In all cases, Apple seems poised to significantly upgrade the iPhone’s battery between this year and the next.