The C-Motive guys have PR all over the web.

Electrolytic capacitors can have far more capacitance than air capacitors. That's the basic concept here.

Here's their patent.[1] Just scroll through the drawings and you'll see how it works.

Here's the key concept: "Numerous aspects of the
present disclosure cooperate to increase the breakdown field
strength 8406, and / or adjust (e.g. , flatten) the field strength
trajectory such as : the permittivity of the dielectric fluid; a
selection of fluid constituents to maintain a permittivity
profile related to operating temperatures; protection of the
dielectric fluid from impurities, presence of water, and / or
presence of gases ; providing a surface smoothness of the
electrodes 8402, 8404 (or portions thereof), related surfaces,
and/ or a housing inner surface ; rinsing / removal of particles
and / or impurities (e.g., from manufacturing residue, etc.);
provision of a surface treatment on at least a portion of an
electrode, and / or on a surface adjacent to the electrode,
including varying surface treatments for different electrodes;
provision of a coating on at least a portion of an electrode
and / or on a surface adjacent to the electrode, including
varying the coating for different electrodes; provision of a
surface treatment and / or coating on a component at least
selectively contacting the dielectric fluid (e.g., a housing
inner surface, a packed bed, a side chamber, flow path,
and / or eddy region ); protection of composition integrity of
the dielectric fluid (e.g., managing materials of bearings,
seals , plates , etc. to avoid material breakdown and / or
introduction of degradation constituents that negatively affect the
performance of the dielectric fluid ); introduction of a field
disrupting additive into the dielectric fluid ( e.g., a coated
metal oxide, a nano-particle, and /or a conductive particle
having a conductor that isolate the conductive particle from
physical contact with the dielectric fluid ); introduction of an
ion scavenging additive into the dielectric fluid ( e.g., BHT,
antioxidants, etc. ); management of gap distance (e.g., using
bearings, magnetic separation, a separation assembly, etc.);
and / or selected field weakening at certain operating conditions.
The utilization of various field management aspects of
the present disclosure allows for an increased average field
strength in the gap, while maintaining a peak field strength
below a breakdown threshold 8406, thereby increasing
capacitive energy storage and consequent performance of
the ESM 1002."

This thing is sort of like a high voltage electrolytic capacitor with moving parts. They go to a lot of trouble to
deal with most of the problems that happen inside capacitors, plus the special problems from
moving parts. They had to go all the way to a pumped fluid system with
filters, to keep the dielectric fluid cool and clean. Many electric car motors have liquid cooling, so it's no worse than that. It does mean this is probably a technology for larger motors, because the motor requires some accessory systems.

It's not clear that this is a win over magnetic motors, but it's reasonable engineering.

[1] https://patentimages.storage.googleapis.com/cf/eb/f0/6d48f07...