The solution is to remove the Panasonic P2 cards before putting the computer to sleep. This is an issue with the Panasonic P2 card Macintosh driver. Sonnet is working with Panasonic to resolve this issue.
A battery should be capable of providing 12Volts @ 3 Amps and have an XLR 4-pin power connector. Nominal power usage of Qio is 9W, and attached F2s are 8 Watts each. An example of a compatible battery is the Bescor MM7XLR-NC (BC-500 charger sold separately) that can provide 12Volts @ 7.2Amps and has a 50 Watt-hour capacity. This battery could power a Qio for 5.5 hours, or a Qio plus F2 for 3 hours.