If you want a refreshing drink, you can put your Urban Bottle in the freezer, as long as it's only for a short time. The liquids will tend to freeze and expand, damaging the materials of the container.
Any deformation resulting from this type of negligence will void the warranty.
Putting your Urban Bottle in the fridge is completely safe and will not cause any damage to your bottle.
N.B. Clima Bottle must NEVER be placed in the freezer or left in freezing condition, as this would damage the bottle and its thermal capacity (see Warranty).
Why don't you just put in your Clima Bottle few ice cubes to prolong the temperature retention of your cold drinks?