Well, yes but,... typical use case for a motor vehicle, which is taken into account at the design stage, is not only the battery but the entire drivetrain must be functional when conditioned down to -40 degrees (assuming all components are within their operational spec limits).
That means the battery must be able to crank the engine over, and the ignition (and electronic fuel system, considering vehicles produced in the last 4 decades), must be able to function at a level sufficient to start the engine.
This becomes tricky when the battery is impaired by the cold, at the same time the lube oil is tending to congeal, resulting in very slow cranking and severe voltage dips on each compression stroke. BITD when I was involved in this stuff, that meant the ignition and fuel had to function down to 6 volts (in the case of a 12 volt system).