One of the leading causes of roadside problems is the battery. Check that the battery electrolyte is up to the proper level by removing the battery caps and looking inside.
The most common battery type today are maintenance free batteries. Maintenance free batteries have sealed caps and require no checking. But some batteries say maintenance free but do have removable caps. These should be checked in the usual manner.
Finally, check the battery to see that there are no cracks or holes in the battery casing itself.
If the battery is three or four years old, consider replacing it.