However, electrical energy consumed is often higher than what a production-line generator (e.g. alternator) of the engine can supply.
All electricity storage components from batteries to capacitors are capable only of storing direct current.
The losses are in general higher than direct kinematic linkage of intake air compressor to engine crankshaft.
Several companies sell low-cost aftermarket products, claimed to be electric superchargers.
These devices are typically simple ducted fans or blowers, often directly repurposed from marine and naval supplies, and are simply not capable of providing an intake manifold pressure increase, or a flow rate greater than what an engine draws.