There it is again: Another automaker makes a big announcement about its electrification plans with a battery manufacturer. Going by previous proclamations, that’s not just ambitious but far-fetched.

Ford Motor Co. and SK Innovation Co. announced they’re partnering to spend $11.4 billion on three electric car battery plants across the U.S., making it the most sizable investment in the automaker’s 118-year-history.

The deal to build the biggest battery plant ever in America would catapult the South Korean firm to the status of a leading battery maker in the U.S. and is also its largest single outlay.

All very big. It comes at a time when President Joe Biden’s administration has been talking up electric vehicle subsidies, including tax credits. In addition, anything made in the U.S. or with higher domestic content, including battery cells, would get more government support.

That’s on top of a new national blueprint for lithium-ion batteries, making it perfect timing for Ford and SK’s blockbuster investment. There’s more to consider, however. Beyond the potential feats the investment brings for the companies, it’s worth taking a closer look at their plans and the batteries they are promising.

Through the 129 gigawatt-hours of battery annual production capacity they will build, the firms expect to produce 1 million power packs for sport utility vehicles and trucks (like the all-electric F-150 Lightening pickup Biden recently took a ride in.) SK’s focus has been on commercializing high-nickel content batteries, or NCMs.

Five years ago, it developed the NCM811 and now the Nickel 9 battery that’s 90% nickel. This, the company says, will “be mass produced in the U.S., powering Ford’s F-150 Lightning.” For starters, this type of battery has not yet proven to be entirely safe. While SK hasn’t registered an EV battery-related fire, high-nickel content power packs — although they deliver significant energy — have been known to be chemically  unstable and prone to combust. Such batteries forced General Motors Co. to recall every EV Bolt vehicle that it’s made since 2017, at a total cost of $1.8 billion to the firms involved.

The cars were equipped with the NCM type made by another South Korean company, LG Energy Solution, a unit of South Korean industrial giant LG Chem Ltd.

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