But as yet, there's no adaptor for either Airplanes or Cars, none for DC period. This is a sad state of affairs. Hopefully someone is working on it and can come up with a solution soon. That would be the first step towards getting a worthwhile external battery pack. Something with maybe two hours of power for high-intensity use on the 8890. Apparently, the big issue is the adaptor plug. I found some batteries that are near market, a pair of them (10.8 vdc, 6 amp output via Smart-Bus, with 98 watt hours total capacity) wired in series would give us about that two hours of power. I've emailed with the company and they are interested in figure something out.