Product1 distinct publisher3 min readUpdated
Robert Lee puts solid-state in phones about ten years before cars. A 12 GWh plant at Dunkirk and Chinese pilot lines due in 2027 are built on the opposite reading.
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Lee's claim is narrower than general scepticism, which makes it harder to wave away. He grants that small cells already reach good energy density; the difficulty scales with the format, and at the very large sizes he says most companies are struggling [4]. Nothing in that requires the chemistry to fail. It requires the factory step to stay unsolved, which is a different proposition from the one being funded.
The carmaker demonstrations look like counter-evidence until you read the labels. Mercedes ran a prototype EQS almost 750 miles on Factorial Energy cells, BMW has put a Solid Power pack into an i7, and Stellantis is testing a pack in a Dodge Charger Daytona [8]. Two of the three are semi-solid rather than fully solid, and TNW's reading puts that distinction at the centre of Lee's argument, running through most of the launch dates in the field [9]. A semi-solid pack in a running car says nothing about whether a fully solid large-format line can be built.
Then the range figure nobody sets side by side. That near-750-mile prototype run [8] is roughly 1.9 times the range LG says it will get from the lithium manganese rich cells it is developing with General Motors [15], cells that use far less nickel and cobalt and are meant to cost about what a cheaper lithium iron phosphate pack costs [11]. One of those numbers is a single demonstration drive. The other is a cost-per-mile claim about volume output. Buyers are choosing between them, not admiring both.
The interest is worth naming. LG sells lithium-ion and has just opened a plant in Lansing making it [2], so its president talking down a competing architecture is testimony with a position behind it. The hedging cuts the other way, though: the company is preparing 46-series cylindrical cells in Arizona and running a sodium-ion pilot for storage, in a market where CATL commercialised sodium first [12]. A firm spreading bets across that many chemistries is hedging its own forecast as much as anyone else's.
Europe has less room to hedge. Northvolt's collapse left the continent's new plants in Taiwanese, Korean and Chinese ownership [13], and TNW's conclusion is the awkward one: if large-format solid-state really is ten years out, the route back runs through incremental lithium-ion improvements Europe does not currently manufacture at scale [14]. The ground broken at Dunkirk in February [6] assumes the leap arrives sooner than that, and a plant sized for automotive cells that has to sell into phones and specialist formats is a different business than the one that was financed.
One pair of dates is worth holding onto. Chinese pilot lines are targeted for 2027 and LG's incremental cell is promised for 2028, a year apart [16]. Both theories of the decade get their first serious test inside the same twelve months.
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Ranked by verification strength, evidence, and original report placement.
LG Energy Solution says the unsolved problem in solid-state batteries is making large cells at scale, and expects the technology to reach smartphones roughly a decade before electric vehicles.
LG Energy Solution has just opened America's newest battery plant, in Lansing, where Robert Lee spoke at a media roundtable.
Robert Lee, North America president of LG Energy Solution, said: "The problem with solid state is large-scale production."
Lee said small formats reach good energy density, but "if you're making very large form factors, most companies are struggling."
ProLogium broke ground in February on a 12 GWh solid-state plant in Dunkirk, described as Europe's first solid-state gigafactory.
Mercedes ran a prototype EQS almost 750 miles on cells from Factorial Energy, BMW has put a Solid Power pack in an i7, and Stellantis is testing a pack in a Dodge Charger Daytona.
Evidence-backed comparisons of source perspectives and observed adoption signals. Read the methodology
Which Builder, Operator, and Investor concerns the observed source mix emphasized—not a truth score.
Evidence, demonstrated adoption, hype gap, incentives, and confidence are assessed independently, each on its own current evidence. How these are measured.
Named executive quotes, single outlet, uncorroborated third-party milestones
The core assertions are direct on-record quotes from a named executive at an identified event, which is strong provenance. But the cluster has exactly one publisher, the surrounding milestones (Dunkirk groundbreaking, carmaker prototypes, Chinese 2027 targets, an unnamed Dutch startup) are reported without documents, figures or rebuttal, and no test data supports either the large-format difficulty claim or LG's >400-mile 2028 promise.
Plants and prototypes real, large-format solid-state production absent
There is genuine physical activity: an opened Lansing plant, a 12 GWh Dunkirk groundbreaking, three carmaker prototype vehicles, Arizona 46-series preparation and a sodium-ion pilot. None of it is large-format solid-state cells in volume production, and two of the three vehicle demos are semi-solid, so deployment sits at prototype-and-construction stage.
Field launch dates run ahead of demonstrated large-format cells
Positive but moderate: the promised timelines in this field (Dunkirk capacity, 2027 pilot lines, prototype range headlines) outrun the demonstrated ability to build large cells at scale, and the semi-solid labelling issue inflates apparent progress. The gap is not larger because this article is itself the deflationary correction, is explicit about the semi-solid caveat, and shows the incremental alternative arriving only a year after rival pilot dates.
Incumbent's caution flatters its own roadmap; capex-committed rivals need the opposite
The pessimistic timeline comes from a lithium-ion incumbent that in the same briefing promoted LMR with GM, 46-series cylindrical cells and a sodium-ion pilot, so slower solid-state is commercially convenient for it; conversely ProLogium, the Chinese makers and public funders have committed capital and subsidies that depend on the fast reading. These are disclosed structural interests visible in the source, not hidden ones, and the article does not interrogate LG's stake.
Well-sourced quotes, but one publisher and no rebuttal
Confidence is moderate: the executive statements are on the record and internally consistent, and several adoption facts are checkable in principle. It is held down by single-publisher coverage, absence of any response from the companies whose timelines are challenged, unquantified technical and cost claims, and forward-looking dates that cannot be evaluated yet.
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