Electrolytic capacitors use the chemistry to make a very high dielectric allowing the plates to get very close and increase the capacitance and decrease the size.

A cell in a battery is a capacitor then converts the charge on the plates into chemical energy and vice versa allowing much more energy storage and a flat operating range as the plates charge is replenished by the chemical reaction.

This article doesn't go into details but it sounds like the breakthrough is a much better dialectic then storing energy in a chemical reaction.

They’re more of a hybrid technology. They have some great applications.

Like temporary storage when using regen from a car. They can buffer the energy and help with a rapid acceleration.

Dash cam in a car. They can charge the cap and in the event in a malfunction / event. The camera can continue to record.

Solar lamps. Charge during the day. Release energy during the night.

They’re poor at long term storage. Great at fast and temp storage.

Upvoted because this is true. I knew that information so I can confirm it. I swear I did.