Young companies such as Sila Nanotechnologies, Solid Power and QuantumScape develop new battery technologies that could offer a faster charge and greater autonomy to electric cars in the future. Currently, there is nothing better than the lithium-ion batteries to power electric cars and mobile phones or “smartphones”.
Many of the more than 3 million electric vehicles in the world are powered by lithium-ion batteries, but as the automotive industry moves towards an electric future, a more advanced and powerful battery is required.
In coming future lithium-ion batteries will replace in large scale
“Lithium is reaching a limit, if you really want to increase energy density, you have to opt for a completely different paradigm,” says Yifei Mo, professor of materials science and engineering at the University of Maryland, CNBC. Higher energy density means cheaper and lighter batteries with more autonomy.
Fortunately, there are young innovative startups that try to build better batteries, with lower costs, improved energy densities and better performance for industrial products and electric vehicles. These batteries would charge faster and offer greater autonomy.
“It took us eight years and probably 35,000 iterations of our material synthesis just to have something that is commercially ready,” says Gene Berdichevsky, CEO of Sila Nanotechnologies. Sila is just one of several battery manufacturers that recently received significant funding to continue improving their technology. Last year, the company based in Alameda, California, received 70 million dollars in financing from several investors, including Siemens, to build its first commercial production line for silicon anode batteries. That’s exactly a decade after being co-founded by Berdichevsky, mechanical and energy engineer and former member of Tesla, who led the development of the battery system in the Tesla Roadster (the car that SpaceX, also founded by Elon Musk, put into orbit in 2018).
The new batteries will reach mobile phones first
The emerging variations of the current lithium-ion battery have taken about 10 years of research. Currently, startups are preparing for the commercial sector, a deployment that will take several years to execute massively. “The amount of material required for a car is the equivalent of 10,000 mobile phones or 100,000 smartwatches,” says Berdichevsky. “First we will start with mobile devices and in the next five years we will work with automotive partners.” One of the current partners of Sila is BMW.
Current lithium-ion batteries are limited in their material parts and energy density. The new battery technology seeks to improve the safety and energy efficiency of lithium-ion batteries, eliminating the risk of fire if the battery is overheated or damaged.
Each lithium ion battery is composed of four essential parts: the anode and the cathode, the electrodes that hold each lithium ion cell, a liquid electrolyte and a separator. Positive and negative currents are created as the electrolyte transports lithium ions through the separator to and from the anode and cathode. This is the process that generates the charge that is stored in the battery.
If the chemicals that form the anode and the cathode, respectively, the graphite and some type of metal oxide, get too hot, it can break the physical separator, which exposes the highly flammable electrolyte (remember when several Samsung Galaxy Note 7 mobiles exploded, putting the safety of people at risk). The maximum energy density of lithium ions at present is approximately 260 Wh/kg. By comparison, most current electric cars have between 220 and 250 Wh/kg.
Battery in solid state
The battery in solid state is one of the new technologies. It replaces not only the graphite anode with one made of lithium metal but also the liquid electrolyte and the separator with a solid piece, usually of ceramic, glass or fire retardant polymer. This is the focus of Solid Power, a solid-state battery manufacturer based in Colorado that received 20 million dollars in financing in 2018. According to the executives of the company, the battery they are developing has 50% more energy density.
The QuantumScape firm, created by Stanford University is also developing a solid-state battery in partnership with Volkswagen. Last year, Volkswagen increased its participation with an investment of 100 million dollars. According to the press release, the QuantumScape battery would allow the Volkswagen E-Golf to reach 750 km (its current range is 300 km) with a single charge, comparable to the ranges reached by conventional fuel vehicles. According to Volkswagen, the QuantumScape battery should offer a faster charging process and be much lighter than current lithium-ion batteries.
However, it is likely that solid-state batteries will not be available in bulk until the next decade, as a vice president of Nissan said last year. Even the QuantumScape release establishes a commercial production goal for 2025.
“It’s an emerging technology in the earliest stages of commercialization,” said Dean Frankel, head of business development at Solid Power. While some startups are working to perfect the battery in a solid state, others like Sila Nanotechnologies hope to take advantage of current lithium-ion manufacturing processes to bring batteries to market quickly. Instead of creating a battery in the solid state, Sila simply replaces the graphite anode with one composed of silicon, a material that absorbs lithium ions faster than graphite.
In addition, most lithium-ion batteries with graphite anodes have a charge rate of less than 1%. The startups that develop new cells with silicon anodes say that the charge rates of their batteries are much better, a key differentiator to allow their future use in an electric vehicle since most people do not want to wait more than one time to load the car. “We can maintain a charge rate 10 times faster than a conventional graphite cell,” says Robert A. Rango, CEO of Enevate.
Next-generation lithium-ion batteries with silicon anodes
The Californian company, which is working on the creation of a next-generation of lithium-ion batteries with silicon anodes, is endowed with 111 million dollars in funds, which includes an investment made last year by the Korean battery company LG Chem. Rango says that Enevate, whose batteries have been in operation for 10 years, is about a year and a half away from the first commercial deployments of its technology, probably on electric bicycles and scooters.
However, silicon anode batteries have a potential drawback: the silicone material swells, which mean that each charge causes the battery to deteriorate. It is a problem that both Berdichevsky and Rango claim that their respective companies have resolved.
“Silicon expands, and that has been one of the challenges of the industry,” describes Rango. “In our cells, we have been able to contain the expansion; our cells have specifications that meet the requirements of electric vehicles.” What are those requirements? That a battery can be charged at 80% after it has been charged and discharged 1,000 times. The long working times of these startups reflect the complexity of battery technology, fortunately, there are brilliant minds working on it and a lot of money invested.