iWatch to tap LG Chem’s energy efficient stepped batteries, rumor has it

iWAtch C (blue, Apple Store, Martin Hajek 003)

As Apple continues to build up its team of world-class sleep researchers, medical device experts and biosensing ace engineers for the iWatch team, the rumor-mill is in full swing with related chatter originating from the company’s vast network of Taiwanese suppliers and contract manufacturers.

The latest rumor: the company is tackling battery challenges said to plague the project by using so-called stepped batteries, a technology offering better longevity and enhanced energy density versus the traditional solutions.

Stepped batteries can be applied to different shapes and, as a bonus, boost capacity by as much as sixteen percent. Conveniently, Apple recently filed for a patent detailing a flexible battery design that specifically mentions wearable devices…

The Korea Herald reports that “Apple has confirmed” (how?) plans to use lithium-ion batteries for the iWatch. The notion flies in the face of The New York Times which last week mentioned solar and motion-charging for Apple’s wearable device.

The company will ostensibly source iWatch batteries from Samsung SDI, Tianjin Lishen Battery and LG Chem, wrote The Korea Herald.

iWAtch C (three-up, Martin Hajek 001)

LG Chem is especially interesting.

A source told the publication that Apple’s engineers chose LG Chem’s stepped batteries because they offer “better longevity than others and can be applied for different shapes”.

Stepped batteries consist of layers of batteries and are said to have around 16 percent more energy efficiency than a traditional battery, as the step-like design reduces unused space in the battery pack.

LG Chem told investors it would target the premium mobile market with stepped and curved battery designs. It’s interesting that Apple’s flexible battery patent is its very first filing to specifically mention wristwatches, at least to my knowledge.

Apple patent (flexible battery pack, drawing 001)

Curved battery designs would reduce wasted space and improve reliability because the entire battery pack wouldn’t fail should one of its cells go offline.

Two Apple patent filings dating back to October 2011 outline enclosing battery components in a flexible pouch that molds to a product.

Again, this would help fit a tiny battery inside the iWatch.

It’s worth mentioning Apple could supplement the traditional lithium-ion battery with the rumored solar charging techniques. On the other hand, solar charging has only one-tenth of the energy efficiency of the traditional lithium-ion batteries so it isn’t clear whether using it would yield meaningful benefits.

The source asserted that the iWatch is due for release in the second half of this year, adding it won’t have a curved screen because there would be “no point in making a curved screen that would be at most two inches wide” (and I agree).

The device is said to use OLED screens, which we’ve suspected for a while.

iWatch mockups via 3D artist Martin Hajek.