Originally Posted by simplechamp

This might come into play as well, posted on the Hyperion website: "Recent changes in international shipping regulations limit single cells to 20Wh, and packs to 100Wh." It's supposedly for all international shipping, not just HK Post.

Basically, for international shipping a single lipo cell can only be 5400mah max capacity, and the biggest pack can be a 5S 5400mah. Anything bigger than that will need to be split into two packs (still wrapped together in same heatshrink, but as far as the circuit/wiring is concerned they are separate) that will need to use a jumper wire to combine them back into one pack when it arrives at the destination.

There is a thread about this in the "General Electric" section of the forum.