I just got my ST Hub (v2) and have connected up 1 of my ZSMOKE detectors.
I am trying to test the push / text notification, however, there seems to be a problem. I have configured the push / text to send to my phone.
I do see notifications under the Activity feed, however, if i press the test button, I do not receive a test message.
If I remove the batteries and go to my room and select the device, the device still shows as 91% battery, without any indication that the connectivity is lost
Correct. There is no inherent functionality in SmartThings to notify you when a Device is offline (out of network, dead batteries, etc.).
That is too bad that it cannot register loss of connectivity and notify. But at least I know it is behaving as designed.
How about the ability to test the push / text notification? I press the test and I do get a notification on my phone, however, I do not get a text message as expected / configured
Frankly, for smoke (no CO), you can test by burning a bit of a page of paper a few inches away. Just have a pail of water to drop it in… 
You can also test with canned smoke. It’s designed just for this.
There is also a canned product for testing CO. (You can likely find this elsewhere and possibly cheaper, just did a quick amazon search for proof of existence)
http://www.amazon.com/Safe-T-Alert-Carbon-Monoxide-Tests-SA-HHTG-1/dp/B004A2YFI2/ref=pd_sim_328_7?ie=UTF8&dpID=31yh5A%2BkIgL&dpSrc=sims&preST=AC_UL160_SR160%2C160&refRID=0Q5JYQ9H3ZRGN1W407RM
Right next to the “canned air”. Geesh… that’s a nice scam! Do they have canned flatulence too? 
Of course
Thanks for the advice / products. I will give the canned smoke a try.
I did confirm that the text messaging is working by defining a custom presence rule.
Thanks for all of the support. looking forward to adding to my connected home configurations
that’s some pretty expensive smoke.
CO and smoke can be made with incense or cigarettes. You might have to cup the the sensor hole to increase the concentration in order to reduce the detection time.