Positive ions are cation and result when an atom loses electrons.
EXPLANATION:
Atoms gain or lose electrons in their shells. Because of this atom either it will lose negative charge or gain it then becomes an ion. Positive ion is formed when an atom loses negative charge or electrons. It gets attracted to cathode during electrolysis in this case.
When an atom gains an electron it becomes an anion.Valency is calculated based on the number of gained or lost electrons by an atom and is specified as '+' sign for positive ions or cations and '-' sign for negative ions or anions. For example: Na+, Cl- etc.