The Apple Watch exemplifies the current state of wearable technology. Unveiled in November 2014, Apple's first product “designed to be worn” embodies much of what’s going on in the wearable industry – from the exciting, such as useful but cool and secure functionality, personalization, appealing styles, and comfortable yet sleek form factors, to the most challenging aspect; battery life. Despite all of the advances in other areas, the Apple Watch is expected to still require daily recharging when it comes to market in 2015.
There are three basic ways to address battery life for a given device: choose a more advanced battery technology, improve charging, or increase efficiency. Let’s have a look at each approach as it relates to the Apple Watch.
Apple has not specified how the still evolving Apple Watch will be powered, but most likely it will use the currently leading battery technology for mobile devices, lithium-ion batteries with cobalt-oxide electrodes. Lithium-ion battery technology was developed in the 1970s, with commercialization of the cobalt-oxide electrode material in 1991. Though this battery technology dwarfs its rivals in performance, it is nearing its theoretical limits. Newer battery concepts are in development, such as lithium-ion batteries with tin nano-crystal electrodes that are more effective at absorbing and releasing lithium ions than cobalt oxide electrodes, potentially doubling the energy capacity. However, these and other next-generation battery chemistries with even greater potential are a ways from being commercially available.