Originally Posted by CanucksHKG

Battery aside, I'm pretty sure an electric skateboard is above and beyond the size+weight you can carry onboard. You might want to start looking at alternatives or see if you can still get a refund from your retailer.

Originally Posted by IanFromHKG

I think they "should" say no. The list of prohibited items says:
QUOTE
For safety and security reasons, dangerous goods such as those listed below, must not be carried in passenger's baggage (checked or unchecked):
...
corrosive materials such as mercury (which may be contained in thermometers or blood pressure gauges), acids, alkalis and wet cell batteries
UNQUOTE

Even though it is sealed, yours is still a wet-cell battery, containing a corrosive substance - acid.

Having said that, the rules also prohibit carriage of compressed gases, which didn't seem to faze CX some years ago when I asked if I could check in a small domestic freezer (and I specifically mentioned the compressed gas in the freezer) - the answer was yes, and they took it on board (as check-in) with no problems!

Originally Posted by ACARS

According to the IATA dangerous goods regs which CX comply with the answer is no. It will not be permitted as carry-on. The approval of CX will be required to accept the battery as checked baggage so you should formally notify them now. The call centre staff are most likely not dangerous goods trained and therefore will give you duff info.