The ResMed Power Station II is a 97w/hr Lithium Ion rechargeable battery, designed to power all ResMed S9 & AirSense 10 CPAP machines.
The RPSII Battery has it's own specific power cable which comes with the battery pack when purchased.
The RPSII and AirMini are not compatible. You cannot use the RPSII to power the AirMini, nor will the AirMini power supply charge the RPSII.