A technique that can enhance convenience on each of both sides that distribute and use content under the conditions where use limitations intended to protect the copyright of content have diversified. The trailer battery charge system generally includes a first switching device that allows current to flow to an electrical terminal associated with a trailer battery of the trailer. The catalyst of the fine particle form has a volume-average particle size in a range of from 3 to 20 \u03bcm, based on measurement by a light scattering method for measuring fine particles having particle sizes of at least 0.