Do You Believe Solid-State Batteries Are Really Right Around the Corner?

Despite all-electric vehicles having certain advantages over conventional combustion automobiles, they also have some clear drawbacks that have stifled their adoption rate on some of the world’s largest markets. Solid-state batteries are supposed to close the gap between the two and are allegedly approaching mass-market applications. However, we’ve been hearing a lot about them for years with the relevant voices citing little in the way of tangible progress.

As of now, solid-state batteries have been limited to small devices that are designed to run for exceptionally long periods of time. But they’re exceedingly rare. Most applications have been limited to personal medical devices and the occasional electronic gizmo reserved for the kind of people who buy five-figure designer watches.

But the automotive industry has been talking about how the technology is poised to accelerate electric vehicle sales immediately after implementation for over a decade. They’ll allegedly be able to store far more energy than lithium-ion units — while also being smaller, longer lasting, and quicker to recharge.

They’re even supposed to be safer due to not needing to rely on the liquid chemical reactions used by traditional batteries or the combustible liquid fuels needed by traditional motor vehicles. Punctured lithium-ion batteries occasionally see events of thermal runaway, resulting in flash fires that are exceedingly difficult to put out. But using solid material, rather than volatile liquid electrolytes, is alleged to mitigate this problem.

According to Automotive News, the industry has collectively been targeting 15 minutes or less for batteries with about 300 miles of range in terms of recharge speeds. Solid-state batteries, which the outlet claimed were "just over the horizon," are assumed to be capable of the task and without the kind of energy degradation one normally associates with rechargeable batteries.

While numerous companies are hard at work on developing an application for automobiles, they’re also behind schedule. Promises about solid-state batteries have been tragically reminiscent of industry statements made about autonomous driving. Automotive News, noted that Toyota ( which is arguably the automaker dumping the most money into developing the technology) plans on releasing a commercial unit by 2028, noting that it had originally promised to deliver something by 2025.

But we can go further back than that. In 2017, Japanese media was reporting that Toyota would field a long-range EV using solid-state batteries by 2022. Nissan has likewise made promises that it would see solid-state EVs by 2028 and we’ve witnessed similar claims coming from BMW, Ford, General Motors, Mercedes-Benz, Hyundai, Honda, and Stellantis.

China’s NIO suggested it would launch a semi-solid-state battery (merging the concept of solid-state and lithium-ion) that would deliver over 1,000 km of range by 2023.

Volkswagen, working with QuantumScape on solid-state batteries, also expected to have a commercial breakthrough by 2023. But the claims on the unit were pretty wild. Some estimated that the resulting product would allow VW-branded electrics to drive several thousand miles before needing to be recharged — perhaps showcasing how often novel technologies are undermined by hype.

To be fair to Toyota (and some of the other brands) forward-looking statements are always issued with a caveat. Just because a company is working on something and sets a target date doesn’t mean that’ll be when the new product drops, let alone in large numbers. But the public is still being inundated with media suggesting “game-changing technologies” are just moments away. Automakers undoubtedly know this and are likewise aware that such news helps pump up their share price, so they often play along.

As for how close we really are to seeing new types of batteries totally transform the EV landscape, Automotive News shed some light on some of the obstacles the industry is facing:

The science is there. Solid-state batteries already power medical devices, RFID products and smart watches. However, scaling up the battery size and making it hardy enough to survive the harsh automotive environment greatly increases development and production challenges.

Chief among them are overcoming battery electrode degradation for improved longevity, reducing manufacturing complexity and establishing a secure, stable supply chain. Solid-state batteries use the same chemistries as conventional lithium ion batteries and thus are subject to the same critical minerals constraints.

A major dependability issue stems from the propensity of solid-state batteries with graphite anodes — the most common type — to grow needle-like structures called dendrites when lithium moves to the anode from the cathode. Dendrites can accumulate and grow in the lithium metal that plates the anode with each charging cycle, weakening it and possibly short-circuiting the cell by piercing the barrier separating the anode and cathode.

A second issue is that the electrolyte material used for solid-state batteries tends to crack, swell and break apart as the number of charging cycles increase. Manufacturing and keeping the electrolyte under high pressure is the most common workaround, but that requires tremendously sophisticated and expensive manufacturing equipment.

"The technology works at small scale, but getting it to the large capacities necessary for cars is a challenge," Andrew Colclasure, a battery research scientist at the National Renewable Energy Laboratory in Golden, CO, told the outlet.

The above also shows how the material shortages, assumed to impact high-density batteries for the foreseeable future, will remain an issue for solid-state units. This technology likewise fails to address the energy production needed to accommodate transitioning entire nations over to EVs combining the dominant mode of transportation — and that’s before we’ve even started addressing how long it would take to establish the necessary supplier base to even build new types of batteries.

While we cannot call solid-state batteries vaporware, their use in the automotive realm has bordered on nonexistent. Some automakers have even started suggesting that there’s not much of a point in pursuing them now that lithium-ion applications have improved.

In 2021, Daimler Bus (owned by Mercedes-Benz) actually offered the eCitaro with solid-state batteries manufactured by the Bolloré Group. However, the units were Lithium Metal Polymer units designed exclusively for use in warm weather. By 2023, the company had changed its tune and said that improvements in Nickel Manganese Cobalt batteries had made the preexisting solid-state batteries (which were a much older design) less relevant. Granted, these weren’t the latest and greatest. But the example shows how advancements in preexisting technologies can sometimes upend progress being made elsewhere.

[Image: JLStock/Shutterstock.com]

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