Most portable lithium-ion booster packs work well enough, but their batteries need to be fully charged. Apparently not so for the 750-amp OzCharge super capacitor from Australia-based RescueMate. The manufacturer claims the product will maintain a full charge for up to five years and can be recharged in 1.5 hours. The OzCharge can boost a variety of battery types, such as those found in motor vehicles, motorcycles, ATVs, and two- and four-stroke outboard motors. It’s also claimed to work in extreme hot or cold conditions and to never overheat. Get more information from www.rescue-mate.com.au and purchase for $200 from www.amazon.com.