Found this, it may be of interest, and comments welcome please...
Cool Multi-function DC 5V/9V/12V 3 In 1 Rechargeable Li-ion Battery Pack Black
http://www.ebay.com.au/itm/Cool-Multi-f ... rmvSB=true
Don't know what these mean, maybe translation issues...
* Light weight and higher energy density than any rechargeable battery.
* No memory effect and rechargeable.