In an ultracapacitor, positively charged ions gather on the surface of the negatively charged electrode and negative ions on the surface of the positive electrode.

ECONOMIST: Electricity storage

The ions pass through a charge-specific membrane and are adsorbed onto the surface of the electrode.

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It uses nanoscale materials to boost the performance of its batteries (making an electrode out of nanoparticles increases its surface area, which in turn decreases the battery's internal resistance and improves its ability to store and deliver energy).

ECONOMIST: The electrification of motoring

It consisted of a 100-electrode panel about the size of a baby aspirin that was placed on the surface of the brain at a fold in the motor cortex where hand movement is controlled.

FORBES: Technology