The battery being charged has low recharging resistance and draws a high recharging current from the charging power source, but the battery does not get further recharged. Electrons from the charging power source return to the cathode without participating in any redox reactions to reverse the chemical state of the battery.
Some chargers use a pulsed charge current to break such shorted path, and discharge the battery for short duration as part of the recharging cycle.
Other chargers physically vibrate the battery to shake up the electrolyte.
Others limit the charging current for a specific electrolyte below the threshold for the formation of such electrical shorts, but this prolong charging time and the engineered electrolyte often presents a higher resistance during discharge. This are the low current but long life batteries.
Have a nice day. What is a short circuit on being charged? An Insanity plead.
