It turns out it’s very difficult to know whether an electric or an internal combustion vehicle needs more energy. Manufacturers buy parts from other manufacturers, who in turn buy from other manufacturers, and so on. It’s hard to track energy consumption along this chain. There are researchers who try to do so and make estimates.
The amount of energy required to produce a 100 kWh Li-ion battery is phenomenal. According to a 2005 paper, it seems to be around 220 GJ—the equivalent of 22 tons of oil. According to a 2017 paper, it seems to be around 370 GJ—the equivalent of 37 tons of oil. These numbers seem to dwarf the amount of energy required to produce an entire internal combustion vehicle (or the rest of an electric vehicle, for that matter).
What does this mean? It means that the conclusion that electric vehicles need less energy (or less emissions) is rushed and naive. There’s zero evidence for that.