Tesla announced 48-volt electric systems today at "Investor Day."

Why do automobiles require 48-volt systems, and will the auto industry switch?

Tesla is not the first carmaker to move to 48 volts. Several mild-hybrid cars use 48-volt systems. 

48-volt systems boost power and fuel efficiency in mild hybrids. 

Yet manufacturing giants like Tesla ditching 12-volts for its EVs puts the industry on notice. Why is Tesla doing it?

2021 was Tesla's first transition to Li-ion 12-volt batteries. But batteries drain quickly

Climate and distance between charges are factors.

Like a 12-volt alternator, the car's mileage charges the battery.