Users can connect a car charger cradle for their camera battery to the solar output of the Spark, which is switchable between 6 and 12 Volts.

ENGADGET: Voltaic Spark Tablet Case powers your pad with the Sun's rays

Now the battery is easily removable and can be charged in all sorts of ways, like clipping it into a charger powered by a car battery or solar panel.

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The battery can also be re-charged from a wall or car charger.

ENGADGET: Voltaic Spark Tablet Case powers your pad with the Sun's rays

Using a trickle or "float" charger, often called a battery maintainer, would keep the car's battery charged automatically while it sits.

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