External battery packs are great, except they're hindered only by how much capacity they come with. Exogear's Exovolt Plus is different — it's stackable — meaning you can pile on as many together and create a battery powerful enough to recharge even the biggest power guzzling gadgets.
The Exovolt Plus consists of two parts (each sold separately): a main unit ($90) and a sub unit ($50). The main unit is the half with the USB port, charging LEDs and power button. Each main unit has a capacity of 5,200mAh and can be stacked with what appears to be unlimited sub units (capacity appears to be 5,200mAh as well) to create an "unlimited expandable battery capacity."
If you're shaking your head because you're afraid the stacked batteries might explode, relax, the battery packs have four safety protection features: double circuit protection, overheat protection, short-circuit protection and automatic input/output control. See? Exogear's thought of everything.
Who's the Exovolt Plus good for? It's perfect for people who need to recharge their iPods, iPhones, iPads and any other smartphones and tablets when they don't have an outlet nearby.
Exogear doesn't have a firm release date yet, but the Exovolt Plus is listed as "coming soon" on its website.