Honda cut a battery case from more than 60 parts to 5. Then it cancelled the cars it was for

Mar. 12, 2026 — Honda cancelled the development and launch of three electric vehicles planned for U.S. production, including the Honda 0 Series whose battery case it had redesigned around megacasting. It expects operating expenses of ¥820 billion to ¥1.12 trillion this fiscal year from the reassessment. Here's what happened, what it cost, and what went wrong.

Cost and outcome (as of Mar. 12, 2026)

Outcome: Honda decided "to cancel the development and market launch of three EV models that had been planned for production in the U.S., namely the Honda 0 SUV, Honda 0 Saloon, and Acura RSX." (Honda, Mar. 12, 2026)
Cost: Honda expects "operating expenses of 820 billion yen to 1.12 trillion yen" for the fiscal year, with total losses "expected to be a maximum of 2.5 trillion yen" including later years. Ars Technica put the fiscal-year range at $5.1 billion to $7 billion. (Honda, Mar. 12, 2026; Ars Technica, Mar. 12, 2026)
The engineering: "The battery case and ancillary parts, which generally consists of more than 60 parts, are reduced to only 5 parts." (Honda, Oct. 31, 2024)

What megacasting changed

Honda described megacasting as "indispensable" to the Honda 0 Series' "Thin" and "Light" goals, producing "a highly strong battery case through molding as one piece and eliminating seams." (Honda, Oct. 31, 2024)

"In preparation for Honda 0 series production," Honda said, it "introduced an appropriately-sized 6,000-ton large-scale casting machine for the first time in Japan." The case is cast in sections and joined together; by selecting appropriately sized equipment, Honda said, megacasting also "enables smart manufacturing with low costs." (Honda, Oct. 31, 2024)

The cast sections were joined with 3D friction stir welding, which Honda said causes less heat damage than conventional welding. Battery packs were to be assembled in a "flex-cell" system, with parts delivered by automatic guided vehicles to parallel identical cells so one stoppage does not halt the whole line. (Honda, Oct. 31, 2024)

Honda's engineers also argued against going bigger. Gigacasting, they said, faces "difficulty in ensuring dimensional accuracy, high power consumption, large capital investment, and difficulty in transportation and repair." (Honda, Oct. 31, 2024)

For the body, Honda said it developed "the world's first Constant DC Chopping (CDC) welding technology," using inverter-controlled current to spot-weld ultra-high-strength steel to thin exterior panels. It said the method needs only a new welding gun and software on existing spot welders. (Honda, Oct. 31, 2024)

Why Honda cancelled

Honda said U.S. EV market expansion "has slowed down due to several factors including the easing of fossil fuel regulations and revisions to EV incentives," and that tariffs hurt the profitability of its gasoline and hybrid business. (Honda, Mar. 12, 2026)

It said launching the three models "in current business environment where the demand for EVs is declining significantly would likely result in further losses over the long term." (Honda, Mar. 12, 2026)

Honda also said it could not match newer EV makers in China on software and value, "resulting in a decline in competitiveness," and expects an impairment on its Chinese equity-method investments. (Honda, Mar. 12, 2026)

The Ohio plants

Ars Technica reported that Honda's Anna Engine Plant had added "a massive die-cast operation to make electric vehicle battery packs," and that Marysville had a new robot-filled section ready for the three EVs. "Only now, they won't," Ars wrote. (Ars Technica, Mar. 12, 2026)

Honda says it will strengthen hybrid models instead and introduce future EVs "flexibly from a long-term perspective." Some executives will return part of their pay, cutting top executives' annual compensation by about 25% to 30%. (Honda, Mar. 12, 2026)

What went wrong

Demand, not cost, sank the cars. Honda cited slower U.S. EV demand, tariffs and weaker competitiveness, not manufacturing cost, as reasons. (Honda, Mar. 12, 2026)
Assets written off. Honda expects write-off and impairment losses on assets "intended to be used for the production of these three EV models." (Honda, Mar. 12, 2026)
Estimates are preliminary. Honda called the figures "preliminary estimates" and said actual amounts may differ. (Honda, Mar. 12, 2026)
What we don't know yet: whether any megacast cases entered series production, and what happens to the 6,000-ton machine and the Anna die-cast line.

Our follow-up question for Honda

Will the megacasting and flex-cell equipment be repurposed for hybrids or future EVs?

Sources

Honda, “Four Key Production Technologies that Realize Honda 0 Series' 'Thin, Light, and Wise.' and Engineers' Passion,” Honda Stories, Oct. 31, 2024. global.honda
Honda, “Honda Announces Losses Associated with Reassessment of Automobile Electrification Strategy…,” Mar. 12, 2026. hondanews.com
Ars Technica, “Facing heavy losses, Honda cancels its three US-made electric vehicles,” Mar. 12, 2026. arstechnica.com

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