Fedex and UPS both treat lithium ion batteries as dangerous goods, with the exception of batteries shipped "with equipment" i.e. shipping a laptop with its battery, without the battery being plugged in.
How does that make sense? If item A is dangerous, how does putting item B in the same shipment suddenly make item A not dangerous? Is the non-powered-on laptop capable of putting out fires or something?
The Chinese rule is extremely annoying, but I'm forced to admit that at least it makes logical sense.
[0] https://www.ups.com/content/ca/en/resources/ship/packaging/g...
[1] http://www.labelmaster.com/fedex-battery-shipping-policy