Six phones that already have a silicon-carbon battery and promise up to three days of use without being a brick

The silicon-carbon batteries They are no longer theoretical or a thing of the future: they are here to stay. At the moment, it is the Chinese manufacturers that are betting on this technology, but it is normal that we will soon see mobile phones of all types with these batteries. And the most striking thing is that this technology is not reserved only for the high-end: There are options for less than 400 euros. Let’s first see what this technology consists of and what differences there are with lithium-ion batteries.

Carbon-silicon as one more detail to look at when choosing a mobile

Although many aspects come into play, as a general rule, the greater the battery capacity, the greater the autonomy of a device. The “problem” is that the batteries that cell phones (and other devices) have been using until now, lithium ion onesuse graphite anodes, which has already reached its energy density ceiling. In other words: for one of these batteries to have more capacity, it has to be bigger. And that causes the device that uses it to become a hulk.

This is why silicon-carbon is so important. These batteries, which use this material in the anode instead of graphite, can store much more energy without the need to increase the size of the battery. This means that we can have telephones with a thickness less than 8 millimeters with batteries that exceed 6,000 mAh. Just a year ago it was unthinkable; Today it is beginning to be an accessible reality.

Small note here to keep in mind. If you start searching on the Internet for a mobile phone with silicon-carbon, you may find versions with different capacities. Example: the Vivo X300 Pro has an international version with a 6,510 mAh battery, while in Spain it has arrived with 5,440 mAh. Because?

As our colleague explains Ivan Linaresit all boils down to saving costs, but not manufacturing costs, but transportation. For safety reasons, if batteries exceed a certain nominal capacity (UN3481 regulations speaks of 20 Wh for each cell), transporting the device becomes much more expensive.

Three mobile phones with silicon-carbon batteries for less than 500 euros

As we mentioned above, despite being a relatively new technology, silicon-carbon is not limited to very expensive mobile phones. It is true that manufacturers like Samsung, Google or Apple still do not use these batteries, but we have several Chinese manufacturers that do. Below, we leave you three examples that cost less than 500 euros right now.

Xiaomi Redmi Note 15 Pro+

The cheapest option on this list is Xiaomi’s Redmi Note 15 Pro+ 5Ga device that is currently coming out 300.29 euros with the coupon ‘ESCD18’. It has a 6,500 mAh battery with a thickness of 8.47 millimeters, with enough autonomy for more than two days. It is not the most powerful option nor the one with the best camera, but it does have good fast charging (100 W), a 6.83-inch screen compatible with Dolby Vision and a speaker system that works well.

POCO X8 Pro Max

There are batteries with a lot of capacity on this list, but not as much as the one included in the POCO X8 Pro Max. It is impressive that a mobile phone that is 8.2 millimeters and weighs 218 grams has an 8,500 mAh battery, figures more typical of a tablet than a mobile phone. As we always say, it depends on the use we give it, but it is a capacity that will easily give you between two and three days of autonomy. In addition, it performs remarkably and has a good 6.83-inch screen. Costs 412.79 euros with the coupon ‘ESCD18’.

Realme 16 Pro+

7,000 mAh battery in a thickness of 8.1 millimeters. That’s what this one has Realme 16 Pro+a device that has a telephoto sensor that is not present in the two previous options. Beyond this, it also offers good performance and a 6.8-inch screen that stands out for having a sustained brightness level of 1,800 nits. Translation: we will be able to see it perfectly even on those very sunny days. comes out for 361.24 euros with the coupon ‘ESCD18’.

Do you have a larger budget? So there are mobile phones with greater power, better cameras and premium finishes.

Three mobile phones with silicon-carbon batteries for more than 500 euros

If you are looking for mid-range or high-end mobile phones with silicon-carbon, you have a choice. There are very outstanding options that have just come out, such as the Vivo X300 Ultra either the Oppo Find X9 Ultrabut we are going to give you three options that are very interesting and that, since they have been available for a little longer, we can find something cheaper.

Vivo X200 FE

He Vivo X200 FE It is the mobile phone on this list that has been available the longest, hence we can find it at a very attractive price (582.79 euros with the coupon ‘ESCD18’). In this case, we have a device with a 6,500 mAh battery and 90 W fast charging, which is not bad at all. This device is highly recommended if you like compact mobile phones, since it is less than 8 millimeters thick (7.99 specifically) and has a 6.31-inch screen.

Oppo Find X9

Although he has two older brothers, he Oppo Find X9 It is an interesting alternative now that it costs 895 euros (it came out with a price of 999 euros). In this case we are looking at a 7,025 mAh battery with 80 W fast wired charging and 50 W wireless charging. It has plenty of power with its Dimensity 9500 chip and it has a very interesting camera system that, although it does not reach that of the Oppo Find X9 Proit’s very nice.

Xiaomi 17 Ultra

And we close with the one who, with almost all probability, is going to be in the pool of best mobile of this 2026: he Xiaomi 17 Ultra. It is true that what stands out most about this mobile is its camera (one of the best available right now) or its performance, since it has the Snapdragon 8 Elite Gen 5. Now, that does not mean we should forget its battery, which is 6,000 mAh. It is the most expensive on this list (costs 1249 euros), but it is worth it if we take into account that its RRP is 1,499 euros.

As you can see, there are many different mobile phones with silicon-carbon batteries. What does this tell us? Which is a technology that is already here and is not limited to the most expensive mobile phones: there are very accessible options.

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Images | Xataka, Xiaomi, Realme, Vivo, Oppo

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