Alkaline batteries and spare dry batteries must be sealed, packed up and taken on board in your hand luggage only.
This also applies to lithium batters – keep them in checked luggage not cabin baggage.
No matter what presents you are travelling with in hand luggage – there’s one rule to keep in mind.
Gifts should not be wrapped. This is because airport security staff may well need to unwrap and examine the item.
Ryanair shared the warning (which applies to other airlines, too) on its website.