One concern about hybrids is their battery life. Will the battery in your VW Touareg hybrid (or Porsche Cayenne hybrid) need replacement every 10 years or so? The short answer is no, the long answer is that like any other component that is used, yes of course. But barring any defect, it will not need replacement during the normal lifespan of the car. The factory warranty from VW on the Touareg is 10 years or 100,000 miles which should cover most owners. In reality though, 100,000 miles can be passed in only 6-7 years if you drive more than average. Some things that can effect battery life: First, keep in mind that the VW Touareg and Porsche Cayenne hybrid are not plug in models. Their batteries are charged only by the engine. They have electric only mode but this is only for a very short range. They are not designed, like the Chevy Volt, to run off only the electric motor most of the time. Heat: this is the big killer of batteries. The battery pack is air cooled by a dedicated fan pack at the rear. However, ambient conditions, just like any other car, will take their toll on battery lifespan. Programming: this is part of heat. Most hybrids are not designed to fully charge and discharge their batteries because this is hard on the battery and reduces battery lifespan. Unfortunately, you don't have much control over these conditions or build quality, so the car is designed like how it should be driven - like a normal car!