It's one thing to tie into an eGo or 510 connector once removed from a dead battery or mod. You can find ac to dc adapters with voltage selctors for 3, 6, 9v with some being a little more flexible multipurpose types. But not knowing the milliamps can spell trouble since these are often made for low currect devices as a means of charging the non replaceable batteries in them not suitable for the heavier draw needed to turn things up a bit.
One thing that caught attention earlier tonight was a solar powered charging case. If the current is sufficient from the charge it stores you can plug a usb passthrough into the micro usb port it offers to vape with a short cord attached yet portable since nothing is plugged into a usb port(desktop, laptop, tablet pc) or ac wall plug with usb port. Solar Case - NettMix Custom Vapes
One thing that caught attention earlier tonight was a solar powered charging case. If the current is sufficient from the charge it stores you can plug a usb passthrough into the micro usb port it offers to vape with a short cord attached yet portable since nothing is plugged into a usb port(desktop, laptop, tablet pc) or ac wall plug with usb port. Solar Case - NettMix Custom Vapes