The Galaxy S27 Ultra might fail to beat the iPhone 18 Pro Max where it matters most

The Galaxy S26 Ultra checks almost all the boxes of an ideal flagship smartphone. It comes with a top-level camera, a fast processor, and the latest AI features. There's also a privacy display technology to keep your data safe from shoulder surfers.

However, battery is one department where the phone lags behind its Chinese competitors like the Xiaomi 17 Ultra, which comes with a 6800 mAh cell that was able to keep the device running for 9 hours and 2 minutes in our in-house testing. If the recent rumors are true, the situation isn't changing much even with the upcoming S27 Ultra.

Everything known about the Galaxy S27 Ultra battery size

I have been constantly following all the claims that different tipsters have been making regarding the Galaxy S27 Ultra. There have been multiple and entirely different claims regarding the exact battery capacity of the upcoming phone. In March this year I reported that there are rumors that the device would feature a monster 7,000 mAh battery.

Then, in June, my dear friend and colleague Mariyan posted that leaker Debayan Roy believes that we could see 6,000 mAh. Now, another reputable name, Schrödinger, claims that Samsung could offer either a 5,600 mAh or 5,800 mAh battery in the S27 Ultra. If true, it could finally be a jump from the 5,000 mAh figure with which the company has stuck since the Galaxy S20 Ultra.

Ice Universe dismisses the claim

Ice Universe, a prominent tech leaker, reposted Schrödinger's post about the battery upgrade and mentioned that the claim is totally false. According to Ice Universe, there is currently no strong evidence to support the claim of the upcoming Ultra phone featuring a 5800 mAh battery.

They further mentioned that Samsung SDI might be testing a bigger battery, but that clearly doesn't mean that Samsung MX (Mobile Division) would automatically adopt it in the upcoming device. The tech giant actually sources the batteries of its flagship products from multiple suppliers. So, if one particular supplier is testing a bigger battery, then it could represent their own R&D decision and not necessarily mean that Samsung MX will adopt it in its devices.

iPhone 18 Pro Max vs. Samsung Galaxy S27 Ultra: Apple appears to be winning

I know both iPhones and Galaxy S series come with very mediocre batteries when compared with what you get in phones from Chinese manufacturers like OnePlus, Huawei, and more. Instead of raw numbers, both brands rely on software optimization and chipset efficiency to offer reliable battery life in their flagship products. However, if you put these two head to head, then you will find that the Galaxy phones have been lagging behind the iPhones in the battery department in recent times.

In our in-house testing, we found that the Galaxy S26 Ultra offered two hours less battery life than the iPhone 17 Pro Max. Similar was the case with the previous model as well. The iPhone 16 Pro Max, which features a 4688 mAh cell, lasted for 8 hours and 30 minutes, whereas the Galaxy S25 Ultra with a 5000 mAh battery died after exactly 8 hours.

Well, it's too early to predict, but I believe a similar story will be repeated with the upcoming flagship phones from both brands. I'm saying so because even though the iPhone 18 Pro Max would feature a 5391 mAh cell, it is rumored to easily challenge 7000 mAh Android phones with the help of its new A20 Pro chip and software optimization.

Unfortunately, the chances of the Galaxy S27 Ultra featuring a 7000 mAh cell seem very slim, and thus, the battle seems to be in Apple's favor again. The expected Snapdragon 8 Elite Gen 6 Pro processor will definitely help boost the battery life, but will it be enough to beat Apple? I highly doubt it.

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