Hi Jerry,
I'm glad to help here! We don't carry an Aspire battery; however, the Eleaf iStick 50W looks and works great with the Aspire Nautilus 5ml. Below, I'm posting the link to the Eleaf iStick 50W and to the replacement coil heads for the Aspire Nautilus.
http://www.smoktek.com/Eleaf-iStick-50W-4400mAh-VVVW-APV-Kit_p_1283.html
http://www.smoktek.com/Aspire-Nautilus-Bottom-Vertical-Coil-Replacement-Head_p_1167.html
Best regards,
Brad