Is silicon-carbon the future of battery technology?

Remember when compact phones were mainstream, sliding effortlessly into your pocket and fitting comfortably in the palm of your hand? Over the years, these pocket-friendly devices have been overshadowed by the rise of large-screen smartphones, primarily due to the growing demand for larger displays and bigger batteries.

Although there are still a few small phones in the market, one compromise that all of them have in common is a small battery. Some companies have even stopped manufacturing small phones altogether.

But if you are one of the few people who still miss the joy of typing comfortably in one hand, there is good news — silicon-carbon (SiC) batteries.

This technology essentially allows a battery to hold significantly more energy than a regular lithium-ion battery, but within the same size. 

Honor included the SiC battery in its Magic 5 series phones last year, for the first time ever in a smartphone, and this year, more companies are adopting this technology. As the company behind this innovation is a Chinese company, Amperex Technology Limited (ATL), it is no surprise that the first manufacturers to adopt the technology are also Chinese ones.

Let us compare two large smartphones — last year's Redmi Note 13 Pro+, which has a 5000 mAh lithium-ion battery, and this year's Redmi Note 14 Pro+, which has a whopping 6200 mAh silicon-carbon battery. This is an incredible 24% increase in battery capacity, all within the same weight and footprint (both phones have a 6.67-inch screen).

What exactly is silicon-carbon battery?

A silicon-carbon battery is a lithium-ion battery with a silicon-carbon anode instead of the usual graphite anode. This design allows for higher energy density since silicon can hold much more lithium than graphite.

Silicon has a charge capacity of 420 mAh/g — almost 13% higher than graphite's 372 mAh/g. However, at the initial stage, its use was limited due to its tendency to expand up to 300% during charging, which caused damage over time. The new silicon-carbon hybrid structure solves this issue by combining silicon's capacity with carbon's stability for better durability and performance.

But how does this apply to real-world usage?

Phones with larger capacity batteries 

Let us compare two large smartphones — last year's Redmi Note 13 Pro+, which has a 5000 mAh lithium-ion battery, and this year's Redmi Note 14 Pro+, which has a whopping 6200 mAh silicon-carbon battery. This is an incredible 24% increase in the battery capacity, all within the same weight and footprint (both phones have a 6.67-inch screen).

Now let us consider two smaller phones. The Google Pixel 9 Pro, a 6.3-inch phone, weighs 199 grams and houses a 4700 mAh lithium-ion battery, while the Vivo X200 Pro Mini, a similar sized phone, comes with a 5700 mAh battery, while weighing 12 grams less than the former.

Xiaomi, Honor, Vivo, OnePlus, Oppo, Realme — almost all the Chinese manufacturers have already launched phones with SiC batteries. 

Redmagic, a sub-brand of ZTE, has launched a gaming phone with a 7050 mAh SiC battery. For comparison, the iPhone 16 Pro Max has similar weight and dimensions, which comes with only a 4685 mAh Li-ion battery.

Some companies might use this technology to make their phones even slimmer. Recent leaks suggest that Samsung and Apple are going to launch thinner and lighter phones alongside their regular flagship series. In addition to regular smartphones, foldable phones could also be made slimmer to give them a more acceptable dimension when folded.

Beyond phones

Earbuds, smartwatches, and other wearable devices are also likely to get this technology soon. Augmented and mixed reality smart glasses could also be among the first ones to grab this technology.

Meanwhile, office laptops generally weigh around the 1kg mark at this point. With this technology and the efficiency of the Qualcomm Snapdragon X chipsets, we are likely to see many laptops weighing only 800-900 grams soon.

Electric vehicles mostly use lithium-ion batteries, and a major limitation is that they can go only 150 to 300 miles on a single charge. Adopting SiC batteries could allow this barrier to be pushed further.

Other probable applications may include use in medical devices, IoT devices, gaming consoles, portable gadgets, etc.