Article by James O’Neil from TopSpeed
Solid-state batteries may drive EV enthusiasts to madness before they are ready for production. The long wait has gone from tantalizing to frustrating. But, for those following the latest news in EVs, it is nearly impossible to ignore the perpetual deluge of press releases about how solid-state batteries will have ranges of 1,000 miles and charge in only ten seconds. At this point, despite the billions of dollars that have been poured into the solid-state cause, people tend to respond to the latest extravagant solid-state promises with skepticism instead of excitement.
However, scientific progress cannot be rushed. With that in mind, Mercedes-Benz and its solid-state partner Factorial Energy have announced that they might have gotten one tantalizing millimeter closer to mass production.
Mercedes’ Battery Breakthrough
- Mercedes and Factorial Energy have developed a dry-cathode method for manufacturing solid-state batteries.
- This simplifies battery production and extends battery life.
- Mercedes and Factorial didn’t invent dry cathode batteries, but they are the first to use them in solid-state batteries.
Mercedes and Factorial have developed a dry-cathode method for assembling solid-state batteries. This is said to dramatically simplify assembly.
These two companies have been working on solid-state batteries for a relatively short time, so having a production-ready (or nearly so) battery is quite the feat. They have named their battery project Solstice, a touching (if unintentional) tribute to one of Pontiac’s final convertibles before General Motors axed the brand. If Mercedes and Factorial’s battery project really is going as well as they claim, they could be the first people to actually get a solid-state battery into a working car.
Dry Cathode Batteries: The Heart Of Project Solstice
Dry-cathode, as the name implies, uses no liquids in assembling the cathode portion of the battery. That is, there are no electroconductive fluids in the cathode, nor are any liquid lubricants required to assemble it. This dramatically simplifies manufacturing. Dry cathodes also let the batteries last a lot longer. After all, if the battery has no fluids, then it has no fluids that can slowly dry out.
Mercedes and Factorial didn’t invent dry-cathode. Indeed, it is already used for some (but not all) lithium-ion EV batteries. However, the Solstice project is the first one to successfully use dry-cathode in solid-state batteries.
Dry Cathode May Make Car-Sized SSBs Possible
Dry-cathode assembly makes it a lot easier to produce car-sized SSBs on a production line instead of carefully making them one at a time in a laboratory. Up until now, solid-state batteries have proven fiendishly difficult to produce in a factory setting.
Solid-state batteries are an old technology, but they have only been used for very small devices like hearing aids and pacemakers. Any attempts to make large ones raise a nasty cluster of inconvenient physics problems. Because of this, Mercedes and Factorial’s announcement that they may have a production-ready design is a bold claim.
The Current State Of Solid-State Batteries
- Toyota began solid-state battery research in 2012. The rest of the industry didn’t follow suit until around 2020.
- Most major auto companies are at least dabbling in SSBs. Some are doing so independently, others have entered partnerships with battery companies.
- Most companies claim they will have roadworthy SSBs somewhere between 2027 and 2030.
Toyota launched the solid-state revolution in 2012, when it first announced that it would try to develop an SSB that could power a car. This was greeted with the same skeptical disinterest that a California-based startup called “Tesla” received when it first announced it would make EVs. It’s worth keeping in mind that Toyota announced its solid-state ambitions only four years after the first Tesla Roadster left the factory. At the time, EVs in general still seemed farfetched. This made Toyota’s solid-state plans seem all the more quixotic.
However, as Toyota got tantalizingly closer to making a working solid-state battery, the rest of the industry took notice. In the last five years, nearly every major automaker has gotten in on the solid-state game. A few companies have tried to independently develop their own SSBs like Toyota has. Others have rushed into partnerships with various battery companies. Indeed, it seems like anyone who can slap together a startup can lure in automotive executives bearing money.
Other Solid-State Batteries In Japan
Honda, Toyota’s closest rival in the “reliable Japanese car” market, has also been trying to make solid-state batteries without tying itself to any popup battery companies. It has made the most dazzling announcement of anyone in the still-nonexistent solid-state battery market: it will have a working factory before the end of January 2025. Of course, Honda states that this will be a testing line and not a full-fledged production facility. However, Honda is the first automaker to claim that it will be manufacturing SSBs in a few weeks rather than the near (but not too near) future.
Elsewhere in Japan, Nissan has been developing solid-state batteries. Like Toyota, it has been keeping its date of deployment in the conveniently distant future. Like Honda, it has also built a prototype battery factory. It claims it will have solid-state EVs by 2029. Indeed, solid-state batteries are a key part of Nissan’s long-term plans, which is has dubbed Ambition 2030.
SSBs Have Grabbed The Auto Industry Around The World
At this point, it is easier to list the car companies that aren’t invested in SSBs than the ones that are. Volkswagen got a flurry of press a few months ago because its battery still had most of its capacity after being repeatedly drained and recharged. Elsewhere in the industry, Ford and BMW have followed Mercedes’ lead and found a battery startup to fling money at. Hyundai has also chosen to find a battery company and sign a partnership.
Electronics manufacturer Samsung is developing its own solid-state batteries that it would theoretically sell to automakers. Because solid-state batteries have so far been expensive to make, Samsung announced that it would only offer its SSBs for use in luxury cars.
The Massive Appeal Of Solid-State Batteries
- Solid-state batteries store energy solid matter.
- They have many hypothetical advantages over lithium-ion batteries.
- For various reasons, no one has ever managed to make one large enough to power a car.
As many readers already know, solid-state batteries are simply batteries that store their energy in a solid material. (Other battery types use a liquid or a paste.) They are an old technology, but up until now, they have only been used for very small devices like hearing aids, pacemakers, and (more recently) wearables. Even though over a decade of SSB research has passed without a single solid-state EV, the batteries continue to tantalize the automotive industry. If they ultimately prove a failed technology, it won’t be for lack of funding or effort.
The Advantages Of Solid-State Batteries
In theory, solid-state batteries would eliminate most people’s objections to EVs. They offer much longer driving ranges than lithium-ion batteries. They also are much more resilient to extreme temperatures, both hot and cold. Additionally, fast-charging doesn’t wear them down as fast as it does lithium-ion batteries. (It should be noted that the battery management systems on all modern EVs forestall a lot of the internal damage that fast-charging would otherwise cause.) Additionally, solid-state batteries weigh a lot less than their lithium-ion equivalents.
Why SSBs Are Not Here Yet
To put it simply, physics won’t allow large solid-state batteries to exist (or at least, not without a fight). SSBs are easy enough to manufacture in small sizes— or at least, as easy as battery production can ever be. However, a lot of problems arise when attempting to make them in bigger sizes. One of them is electrode contact. As already noted, the electrolyte in most batteries is a liquid (or paste), which naturally makes perfect contact with the battery’s electrodes. (For those who don’t know their battery anatomy, the electrodes are the terminals through which electricity flows.) Solid matter tends to have a lot of air gaps. And of course, electricity can’t flow through air gaps unless it is arcing, which no one wants to happen inside a battery.
Lastly, solid-state batteries require a lot more lithium than lithium-ion batteries do. Even though the price of lithium has been dropping and looks like it will stay low for the next year or so, it is called a rare metal for a reason. Throughout the electronics industry, there has been a growing undercurrent of worried murmuring that the world’s lithium supply will run out. And if it doesn’t run out, it will become too scarce to affordably use.
EV Batteries Are Still Rapidly Changing
The battery is the only part of EVs that is still in development. Electric motors are, of course, very old and therefore well-understood. Most other aspects of car design carried over from the pre-EV days. No one needed to repeat several decades of load-bearing analysis, aerodynamics, body design, or crash safety studies.
However, EV batteries are a relatively new technology. Of course, EVs are practically as old as the automobile itself. But it’s worth noting that before lithium-ion batteries, no one successfully sold them. But while lithium-ion batteries were good enough to finally give EVs better ranges than 100 miles per charge, they still can’t equal a full tank of gasoline. Regardless of whether solid-state batteries are take off, lithium-ion batteries will not be the final evolution.
Most Current EV Misgivings Are Battery-Related
Many people don’t realize that most of their problems with EVs are related to the battery and not the electric powertrain. Nevertheless, the battery remains the source of most complaints. TopSpeed’s own readers have confirmed that the biggest objections to EVs are range and charging time. If solid-state batteries can live up to their testing-lab promises, more people may decide that the instant torque of EVs is more fun than the roar of an engine.
SSBs Are Still Maddeningly Uncertain
Of course, despite the years of research and industry-wide output of lavish promises (Five hundred mile range! Ten-minute charging time!), no one in the entire global automotive industry has actually bolted a solid-state battery into a car and driven it. SSBs wouldn’t be the first time that the auto industry poured unfathomable amounts of money into a technology that ultimately failed to launch.
Chrysler spent multiple decades on its turbine-powered cars and even built a fleet of working vehicles before axing the program. Mazda’s semi-regular flirtations with rotary engines keep flaring up and then sputtering out. Even today, fully self-driving cars may prove just as elusive as solid-state batteries have. However, solid-state batteries show too much promise for the industry to give up so easily. Mercedes and Factorial’s dry cathode assembly process may prove the key to finally making them viable.
