Lithium-ion batteries have been powering our devices for over three decades, and they’ve only evolved ever since. However, the technology has nearly reached a saturation point in charge-holding capacity, so the time has come for an alternative. Enter Silicon Carbon batteries. Denser and capable of holding more charge, these batteries are paving the way for devices that last longer while maintaining or even shrinking down the form factor of these devices. Here’s everything you need to know about them.
What Are Silicon Carbon Batteries?
Silicon Carbon batteries are the latest innovation in portable battery-powered devices and are predominantly being used in smartphones. They’re denser than Li-ion batteries, packing more charge in the anode, while being almost similar in dimensions or even slimmer than regular Lithium-ion batteries.
By leveraging Silicon Carbon battery tech, manufacturers can include bigger capacity batteries in their devices without compromising on the overall form factor of the devices. Thanks to their density, these batteries can store around 25% more charge. So, technically, a Silicon Carbon battery with the exact same dimensions as a 5,000 mAh Li-ion battery offer up to 6,200 mAh of power.
While the maximum theoretical density of Lithium-ion batteries is about 387 WH/kg, Silicon Carbon batteries can far exceed that threshold at 600 WH/kg. Pure Silicon can hold 3500 WH/kg, but that leads to rapid expansion. Hence, carbon is introduced to stabilize the material.
How Do Silicon-Carbon Batteries Work?
Despite the name, Silicon Carbon batteries’ basic principles remain unchanged. They still transfer Lithium ions to the cathode to produce charge. However, instead of using a Graphite anode, these batteries use a Silicon-Carbon composite. Since it’s denser and holds more charge, the overall size remains the same while the capacity increases.
The reason Silicon-Carbon batteries are denser is due to the difference in elements used to make the anode. In Li-ion batteries, Lithium ions are stored in the Graphite anode, and they essentially slide between the graphene layers. The maximum Lithium ions graphene can hold is in the ratio 1:6. Silicon-Carbon composite can store 15 Li atoms per 3 Si atoms.
If you’re unaware of how a battery works, Lithium ions stored in the anode move to the cathode, which is usually made of Lithium-based metal oxides, mostly Lithium Cobalt Oxide. When you use your device, the ions move from the anode to the cathode, producing the energy required for all the components to function.
However, when you plug in your phone for charging, your charger’s current forces Lithium ions in the cathode to move to the anode. The overall characteristics of both Li-ion and Silicon Carbon batteries remain the same — they last for over a thousand charge cycles with no memory effect and are lightweight.
Advantages of Silicon Carbon Batteries
The main advantage is that due to the Silicon Carbon composite being much denser, manufacturers can pack more power into a rather slim cell. Since Silicon-Carbon batteries use a Silicon-Carbon anode, the absence of Graphite layers means they can charge much faster and efficiently at around 80W or more without a multi-cell configuration.
Last but not least, thanks to the denser batteries holding more charge, manufacturers can make larger batteries or use bigger capacity batteries in devices with smaller or slimmer form factors. This ensures users don’t have to compromise on the design dynamics.
The OPPO Find N5 is a great example where the firm managed to reduce the thickness of the device while increasing the overall battery capacity by a whopping 15% (4,850 mAh vs 5,600 mAh)
Silicon-Carbon vs Lithium-Ion: What Are the Differences?
One of the main differences between Silicon-Carbon and Lithium-ion is the anode material. Li-ion batteries use Graphite, whose charge holding capacity has only improved since Li-ion batteries were introduced. However, it’s much less dense than Silicon-Carbon, and faster charging requires a multi-cell layout. Here’s a table to understand the differences.
Specification Silicon-Carbon Lithium-ion (Graphite) Anode Material Silicon-Carbon Composite Graphite Theoretical Density Around 600 Wh/kg Around 387 Wh/kg Charging speeds Faster Slower, Need multi-cell configuration for faster charging Voltage Range 3.2V – 4.4V 3.0V – 4.2V Size and Weight Denser and could be slimmer Standard size Thermal Stability Better Moderate Cycle Life 1,000+ cycles 1,000+ cycles Charge Holding Capacity 20-30% more than Li-ion Standard
How is Silicon Carbon Different From Silicon Carbide?
You may have seen people using these terms interchangeably, which is understandable if they’re unfamiliar with the tech underneath. But seeing MKBHD make the same mistake in his Galaxy S25 Ultra review was surprising, especially since he also reviews electric cars. While Silicon Carbon and Silicon Carbide are related to batteries and charging, they are fundamentally different things.
Silicon Carbon is used in batteries whereas Silicon Carbide is primarily used in power supplies like chargers, inverters, and other accessories. Silicon Carbide is more in-line with Gallium Nitride or GaN as the industry calls it, which is primarily used in smartphone chargers. Now scale that to meet industrial power supply needs or fast chargers for cars. That’s where Silicon Carbide is used, due to its exceptional voltage handling capabilities and better thermal conductivity.
Phones That Use Silicon Carbon Batteries
A lot of smartphone brands like OnePlus, Xiaomi, Realme, OPPO, and Honor have already switched to Silicon Carbon batteries. This includes the latest OnePlus 13 (review) rock a 6,000 mAh battery despite being much slimmer than its predecessor. Similarly, Tecno’s Spark Slim device boasts a 5200 mAh battery despite being just 5.75 mm thick, thanks to the new tech. The OPPO Find N5 is another great example where the firm leveraged Silicon-Carbon batteries to create an incredibly thin foldable.
While Chinese manufacturers are currently paving the way, it will at least take a year or two for Silicon Carbon batteries to make it to the likes of Pixels and Samsung’s. It’s a bummer that the upcoming Galaxy S25 Edge won’t feature this battery tech, and it would’ve been ideal for Samsung postpone the launch just for this. However, reports do suggest that the Korean giant may use them starting next year.
Are Silicon-Carbon Batteries Less Polluting?
While we would’ve loved to explore the environmental benefits of Silicon Carbon over Li-Ion, there’s just not much information to back our statements. On one hand, Silicon is found in abundance and is everywhere, which would make it environmentally friendly. But the Silica used in the these batteries has to be of the purest form, and that requires a lot of energy.
Not to mention, the tech still uses Lithium and Cobalt and you need tons of water to extract the elements. Therefore, while Silicon-Carbon might be slightly better for the environment, it’s not entirely good either.
What are your thoughts on Silicon Carbon batteries? Let us know in the comments below.
There aren’t any major disadvantages of Silicon-Carbon batteries on the consumer side. Most of the challenges lie on the manufacturer’s side, like the price, potential expansion issues, market adoption, and more. They’re being countered extremely well so far.
There isn’t enough real-world evidence to suggest that Silicon-Carbon batteries last longer than their Lithium-ion counterparts. Theoretically they should since they come with better thermal stability.
While the primary reason is that the tech is pretty new, Samsung’s being cautious because it sells far more smartphones. The firm wants to heavily test the technology to ensure safety.
