Mailing phone with lithium battery

not1but4

I managed to leave my personal mobile (S2) in the UK office when rushing off to get my flight home. Got in contact with one of my colleagues and they will send it in the internal mail on Monday so I should have it with me on Tuesday.

However someone told me there might be an issue with sending the battery and they might destroy my phone.

I had a read of the following link
http://www.royalmail.com/help-and-support/tell-me-about-restricted-goods but I am unsure if I am okay or not?

not1but4

Okay, found out that the internal mail is handled by DHL.
http://www.dhl.ie/en/express/shipping/shipping_advice/lithium_batteries.html

The battery I have is the below one
http://www.amazon.co.uk/1900mAh-Battery-Samsung-GT-I9100-EB-F1A2GBU-White/dp/B00567Y7A6/ref=sr_1_2?ie=UTF8&qid=1427055454&sr=8-2&keywords=s2+battery

Am I okay to send it over the post or not?