The operating voltage of the AC Adapter Kit/Compact Power Adapter/Battery Charger is 100V - 240V and conforms with international standards. Therefore, you do not need a voltage transformer when traveling abroad.
Do not attach any portable voltage transformer to the battery charger. Doing so can damage the battery charger.
Use of genuine Canon accessories is recommended. This product is designed to achieve excellent performance when used with genuine Canon accessories. Canon shall not be liable for any damage to this product and/or accidents such as fire, etc. caused by the malfunction of non-genuine Canon accessories (e.g., a leakage and/or explosion of a battery pack). Please note that this warranty does not apply to repairs arising out of the malfunction of non-genuine Canon accessories, although you may request such repairs on a chargeable basis.
For information on compatible accessories, refer to the camera's instruction manual.