The electrical potential energy difference between two points in an electric field is related to the work done to move a charged object between those points. Whether the work done is positive or negative depends on the direction of the movement of the charged object.
If a positively charged object is moved in the direction of the electric field, from a point of lower potential to a point of higher potential, then the work done on the object is negative. This means that energy is being transferred from the object to the electric field, and the potential energy of the system decreases.
On the other hand, if a positively charged object is moved opposite to the electric field, from a point of higher potential to a point of lower potential, then the work done on the object is positive. In this case, energy is being transferred from the electric field to the object, and the potential energy of the system increases.
It's important to note that the sign conventions used in different contexts may vary. In some cases, the sign convention for work and potential energy might be defined differently. So, when applying these concepts, it's important to be consistent with the chosen conventions and context to ensure accurate calculations and interpretations.