Those are the wrong units. A single cell's capacity is measured in Watt-Hours, which is a unit of stored energy. A factory making some number of cells per hour has its production measured in Watts, which is a unit of power.
The article makes this mistake several times, conflating energy and power in some places, but then correctly saying "150 GWh ... annual capacity" elsewhere.
PS: 150 GWh/annum is just 17 megawatts! This goes to show just how difficult batteries are to produce...
... no no no ... these aren't single use cells, instantaneous power isn't a meaningful unit (I mean energy/time is technically power, but one couldn't compare this to power as measured from a traditional power plant or anything like taht).
If one had to somehow contort the output into watts:
Recharged every week, 150GWh of car batteries would eat ~1GW of grid capacity. It is still a very long way from any meaningful fraction of grid energy (~4TW globally), but watts really aren't the right unit to measure production capacity.
$2.8bln will finance 20GWh production upgrade, therefore Northvolt will need to raise a lot more money to achieve 150GWh production.