Volkswagen’s Solid-state Battery Tests Yield Promising Results; Here’s What We Know

Move over, Toyota. Volkswagen Group may have taken the lead on solid-state batteries. The German auto manufacturer has announced that its battery, co-developed with California-based solid-state battery company QuantumScape, has passed its first tests. That’s right, someone in the auto industry has finally gotten a solid-state EV battery out of the designing laboratory.

According to preliminary tests, the battery retained 95-percent of its capacity after being drained and recharged 1,000 times. While this does not mean that all Volkswagen EVs (including upscale subsidiaries Porsche and Audi) will have solid-state batteries as of next month, this nonetheless is huge news for everyone who has been following the decades-long attempt to get SSBs onto the road.

In order to give you the most up-to-date and accurate information possible, the data used to compile this article was sourced from various manufacturer websites and other authoritative sources, including Car and Driver, MotorTrend, Electrek, and TopGear.

Volkswagen’s Solid-State Breakthrough: A Battery That Is Ready For Testing

• Volkswagen has developed an SSB that stands up to testing.
• After 1,000 charging cycles, the battery retained 95-percent of its storage capacity.
• Volkswagen developed this battery in collaboration with a company called QuantumScape.

Volkswagen and its solid-state battery partner QuantumScape have made a solid-state EV battery that keeps nearly all of its capacity after long use. Or at least, it held up well in a testing simulation of extended use. After draining and recharging the battery 1,000 times, it still had 95-percent of its original capacity. Volkswagen claims that it outperforms the “industry standard” of retaining 85-percent of its original charge. However, the German automotive conglomerate does not cite which standard it has exceeded.

QuantumScape: Volkswagen’s Solid-State Partner

QuantumScape is a solid-state battery developer based in San Jose, California. Like nearly every corporate entity that specializes in SSBs, press releases call QuantumScape an “industry leader.” Since QuantumScape has managed to produce a tentatively roadworthy solid-state battery before anyone else, the praise may be deserved.

The company was founded in 2010, and entered into a partnership with Volkswagen Group in 2012. In other words, it has been corporately and financially intertwined with Volkswagen nearly since its founding. Volkswagen made headlines in 2018 for investing an eye-watering $100 million in its SSB partner.

A Battery With A Long Range And A Longer Lifetime

Volkswagen and QuantumScape haven’t announced any driving range specifications for their solid-state battery. However, they claim that draining and recharging the battery 1,000 times simulated driving for 500,000 kilometers. Some basic arithmetic suggests that their battery will provide a driving range of around 500 kilometers per charge. (This translates to a lifetime range of about 310,000 miles, with 310 or so miles per charge).

While this does not put its range per charge on par with ICE vehicles, it does suggest that the battery will last a long time before it needs replacement (even if it needs to be recharged more often than one would refill a gasoline tank). Most cars take their final trailer ride to the salvage yard long before they reach 500,000 kilometers (or 310,000 miles, depending on one’s region). If this battery lives up to its initial tests, it may be good for the life of the car.

Other Car Companies Are Seeking Solid-State Success

• Toyota has been researching SSBs since 2010.
• Honda has developed a battery that resists dendrites (a problem that kills many SSBs).
• Other major car manufacturers have entered SSB research partnerships.

Toyota has been the vanguard of SSB research, and also the company with the most maddeningly slow progress. The Japanese stalwart of indestructible vehicles began working on solid-state EV batteries in 2010. In the ensuing years, Toyota has racked up a formidable number of patents co-credited with fellow Japanese company Panasonic. More recently, Toyota entered into an R&D partnership with petroleum company Idemitsu.

Toyota somewhat infamously announced that it would bring a solid-state prototype to the 2020 Tokyo Olympics. Of course, the Olympics were pushed back by a year due to the pandemic. But despite getting a one-year extension, Toyota quietly brought no batteries (solid-state or otherwise) to the Olympics in 2021.

Elsewhere in Japan, Honda has also been attempting to make a viable SSB. Honda’s biggest development was to add an internal barrier layer that prevents dendrites from forming inside the battery. (Dendrites are one of the primary causes of solid-state battery death.) Nissan has also put a lot of effort into developing a viable solid-state battery, which it claims will be ready for deployment by 2027 or 2028.

Nio’s Semi-Solid State Battery Has Made A 648-Mile Drive On A Single Charge

Perhaps the most impressive feat in the world of solid-state batteries comes from Chinese EV manufacturer Nio, who has put a semi-solid-state battery into production. Of course, a semi-solid state battery is not a fully-solid state one. However, Nio has actually gotten its battery onto the road- and not just a sheltered proving ground.

The company’s CEO livestreamed a 14-hour, 648-mile drive without stopping to recharge the battery. The car still had three-percent of its charge at the end of the journey.

The Rise Of Solid-State Joint Ventures

In these exciting times for SSBs, it sometimes looks like anyone can form a solid-state battery research firm and attract automotive executives who come bearing generously filled money bags. The lure of solid-state “wonder batteries” has tantalized most of the major companies in the auto industry.

However, no one has chosen to go at it alone. Every automaker dabbling in SSBs has done so in collaboration with outside companies. Ford and BMW have jointly invested in a battery company called Solid Power. Hyundai has entered into a partnership with a different battery firm called Factorial Energy.

The Industry Wants Solid-State Batteries To Succeed, But They’re Not Ready Yet

If one believes the industry hype, solid-state batteries will solve all the problems of EVs. They weigh less than lithium-ion batteries with the same storage capacity. They last far longer than lithium-ion batteries. They’re even less prone to fires than lithium-ion batteries (though lithium-ion batteries are already a lot safer than a car with a half-tank of gasoline).

Fast-charging doesn’t wear them down as badly as it does lithium-ion batteries. SSBs also perform well in severe cold, whereas lithium-ion batteries need to warm up before they can release their energy. In fact, the only problem it seems SSBs can’t solve is the looming threat of a lithium shortage.

The Difficulty Of Making Large SSBs

It should be noted that solid-state batteries are a fairly old technology. Up until now, they have only been used in very small things like hearing aids and (more recently) wearables. So far, they have resisted all attempts to put them in anything large. This is clearly evidenced by the decades-long industry-wide efforts to put them into cars that are only barely starting to pay off.

In other words, no one in the auto industry is trying to invent a radical new battery technology. They are instead trying to make solid-state batteries work in high-power devices, which hasn’t been done before.

The Problem Of Electrode Contact

One of the biggest problems facing large solid-state batteries is getting the electrolyte to contact the electrode. (In other words, making the part of the battery that stores energy touch the part that sends the energy out to the car’s wiring.) If the electrolyte doesn’t touch the electrode, it can’t send any energy out of the battery. With conventional batteries, the electrolyte is a liquid (to be mildly pedantic, the electrolyte is more often a paste to forestall ruinous sloshing).

Basic science says that a liquid makes perfect contact with anything it touches. To make this easier to visualize, imagine a bowl of water and a bowl of dry beans. The water will completely cover any part of the bowl it touches. But with the dry beans, there are large areas where nothing is touching the sides of the bowl. Wherever the battery’s electrolyte isn’t touching the electrode, it isn’t sending electricity through it.

Obviously, the problem of electrode contact isn’t insurmountable. However, it requires extra effort to overcome a shortcoming that conventional lithium-ion batteries don’t have. This is part of why Nio’s semi-solid state battery has already hit the road while the fully-solid state batteries haven’t yet left the testing lab.

Nio’s design more or less suspends particles of the solid-state electrolyte in a liquid electrolyte. That allows for Nio to get the reduced weight and increased capacity of a solid-state battery without forcing a solid electrolyte to contact the electrode as well as a liquid would. (Obviously, semi-solid state batteries are more complex than that, but that’s the general idea.)

The Industry’s Ongoing Obsession With Solid-State Batteries

Solid-state batteries seem like the perfect answer to two of the biggest objections many ICE drivers have to “making the switch.” People often worry about the limited driving range and also the prohibitive cost of replacing a spent battery. The former objection is perhaps a bit of a fantasy since most EVs already get over 200 miles per charge.

However, many people cherish the notion that they will take a long road trip (even if they never do). Even people who acknowledge that they only drive 50-100 miles per day (if that) appreciate a generous safety cushion of extra range. (You never know when you might need it.)

The Long Wait For SSBs

Despite the cumulative reams of patent filings, the increasingly frantic output of press releases, and the astounding sums of money thrown at solid-state batteries over more than a decade, no one has gotten one into a car that has actually been sold.

Chrysler had better success with its failed turbine engine program than anyone has managed to find with SSBs. Before giving up, Chrysler actually got a fleet of Turbine cars onto the road. So far, no one has managed to produce a solid-state EV. No one has even temporarily bolted an SSB into an existing electric car and puttered around a proving track somewhere. (Or if someone has, they didn’t want the press to know.)

Volkswagen Has Made One Small Step For Battery Development And One Giant Leap Of Progress

The most impressive thing about Volkswagen’s battery is that it’s been tested. Granted, the battery has only been subjected to carefully managed laboratory conditions. But given the frustratingly slow pace of solid-state development, Volkswagen has taken a giant leap forward by nudging its battery out of the lab (or at least, from one section of the lab to another). It’s too early to say that solid-state batteries are finally here, but they are tantalizingly within sight.