Group14 Technologies is working to manufacture lithium-silicon battery technology and recently secured $17 million in funding from SK materials.
Group14 Technologies is working to manufacture lithium-silicon battery technology and recently secured $17 million in funding from SK materials to scale up production of its flagship lithium-silicon battery material, SCC55. The investment by South Korean SK materials is a clear indication of global market demand for higher-performing, off-the-shelf battery chemistry.
Group14 Technologies produces a silicon-carbon composite material called SCC55. This material can fully replace conventional graphite in the anode to increase the life and stability of a battery. In an interview with EE Times, Rick Costantino, CTO of Group14 Technologies, highlighted how SK materials’ investment will help to scale production to meet the increasing demand for its flagship product SCC55, positioning Group14 to accelerate the electrification of the automotive industry.
Automotive Industry Likely to Face Materials Shortage — The industry might experience a shortage of graphite as early as next year.
Costantino highlighted how the investment comes at an important time after Group14 announced a commercial manufacturing facility in Washington, demonstrating that it is laying the groundwork to build a national supply chain for lithium-ion batteries to meet the growing demand of the EV market.
Electric vehicle batteries
The three scenarios for a more energetic future of mass mobility will be sustainable energy production, battery storage, and finally electric vehicles (EVs). Enthusiasm for batteries continues to grow strong as EVs gain traction. Their prices continue to fall, and the EV battery market, according to leading analysts, including Technavio, is set to reach $44 billion globally between 2020 and 2024.
The battery is about one-third of the price of an EV. It is the powertrain of the vehicle: the largest, most expensive and most critical component. This element determines range, charging time, performance, handling, power, price, safety and basically all critical aspects of the car.
The cooling systems of electric cars are to always ensure the optimal operating temperature, around 37 ° C (they are often liquid cooling systems). Keeping the batteries from overheating helps decrease the charging time of batteries from fast-charging stations. The advantage of the cells with new electrolytes, additives, and silicon anode material, permits the operating capacity even above 75° C. That innovation will have downstream benefits too, including affecting the sizing (thus the weight) of the cooling/heating systems of the modules. The big difference compared to the classic architecture is the use of a silicon anode instead of graphite.
This seemingly small change offers important performance advantages, providing a much larger specific capacity (3600 mAh/g). On the other hand, however, the famous semiconductor suffers from significant increases in volume (+400%) during charging, a disadvantage that has held back its use over the years.
Chemistry for batteries is important
SK material’s investment validates the performance of SCC55, which allows for an increase in energy density by 50% as Costantino said. Silicon can store more charge than graphite and also improves charging speed. Despite its performance qualities, however, silicon tends to break into small pieces when charged or discharged. To increase its stability, Group14 uses silicon nanoparticles, which also provide a longer life cycle.
“With the improvements, we’ve made over time, we’ve developed a much simpler process now, and most importantly, an environmentally friendly one. We have no solvents, and we basically just take standard industrial materials that are very commonly used to create a carbon and silicon composite for lithium-ion batteries,” said Costantino.
There has been a lot of progress in lithium-ion battery technology, but not so much on the anode side. “For decades, graphite anodes have been the key technology. But until now, there hasn’t been any real work on the anode side. So, we decided to replace graphite with silicon. What silicon can do is 10 times the capacity of graphite. Silicon has 10 times higher gravimetric capacity compared to conventional graphite and is an amazing material in terms of its ability to reduce the size or weight of the battery and have a huge improvement in energy. But the problem with silicon is that it has a huge volume expansion upon processing so you have to create an interface to keep things in balance. The goal is to match the properties of silicon through carbon,” said Costantino.
Developed through a patented two-step process, Scaffold Prime, SCC55’s carbon-based hard scaffold keeps the silicon in the most ideal form-amorphous, nano-sized, and encapsulated in carbon. The result is a drop-in-ready anode material that exhibits exceptional first-cycle efficiency and long life upon lithium-ion battery cycling.
In contrast, silicon nanowires require appropriate additives to be the building block of innovative silicon anodes for lithium-ion batteries. Carbon materials, other metals, metal oxides, polymers, silicon-based materials and other special compounds are being investigated in order to arrive at the reliable, repeatable, and industrially producible application.