How long does the battery last after a full charge? January 29, 2015 16:24 Follow Between 2-4 days, depending on your daily usage. Related articles How can I change the quartz watch battery ? I have plugged ZeClock to my computer but it seems that it is not charging… no battery indicator shows … How long should I charge ZeClock for the first time? Can I charge my ZeClock with a wall plug (110V)? Can I wear ZeClock while swimming / showering?