As Lithium-Ion Batteries Go, So Do Wearable Devices
Imagine relying on a wearable device for medical purposes. You would want a device with a battery offering maximum life and performance. You wouldn’t want to have to replace batteries or recharge the device multiple times per day just to keep it operational. As such, wearable devices often go the way of their lithium-ion batteries.
Hearing aids represent one of the earliest wearable devices. For decades, the biggest challenge of a working hearing aid was the disposable battery that powered it. Disposable batteries were adequate for those devices, but modern wearables are more complex. Not having reliable batteries to run them makes using one difficult to justify.
Justification becomes even more difficult when you are talking about a wearable that is not medically necessary. Take audio sunglasses, for example. As far as any of us know, there is no medically necessary reason to wear such a device. So are audio sunglasses even worth investing in if their batteries are terrible?
Three Hours vs. Nine
Apple Insider recently reviewed a pair of audio sunglasses from Evutec. They were compared to a similar pair of sunglasses from Bose. The Bose pair has an average battery life of about three hours of playtime. Apple Insider’s reviewer got more than nine hours of play out of the Evutec pair.
This comparison perfectly illustrates the point. If you were using a pair of Bose audio sunglasses throughout your workday, you would have to recharge them at least once, perhaps even twice. You could get a full day out of the Evutec pair. Assuming all other things were equal, which pair would you choose?
Now, let us translate the same principle to hearing aids. A hearing aid with a 15-hour lithium-ion battery is more attractive than one with a five-hour battery. And for the record, these numbers were chosen completely at random. The point is to establish that longer life batteries make for better wearables.
Energy Density Is Key
Utah-based Pale Blue Earth explains that energy density is key to lithium-ion batteries. Lithium-ion cells offer a lot more energy density compared to disposable alkalines. They are also more energy-dense than both NiCad and NiMH batteries, though the difference is not so drastic.
Energy density directly affects battery life. So does the discharge rate. Thus, a NiMH rechargeable battery would not work as well in a hearing aid as a NiCad. Both have similar energy densities, but NiMH batteries discharge at a faster rate.
Lithium-ion beats them both for energy density and discharge rate. That is why modern electronic devices are so often powered by li-ion batteries. Lithium-ion powers your cell phone, tablet, laptop computer, and so forth. And by the way, lithium-ion batteries offer another advantage: they do not require an external charger.
Pale Blue Earth’s USB rechargeable batteries have the charging technology built-in. You just plug them into a standard USB port just like you would your smartphone. A wearable device with an embedded lithium-ion battery would not need an external charger either. Moreover, there is no need to manually remove batteries to charge them. Just plug the device into a USB outlet.
Better Batteries Means Better Wearables
Wearables were all the rage during the early 2010s. Everyone was talking about how a new generation of wearables would revolutionize everything from medical care to individual communication. Things haven’t turned out as planned, but that’s largely due to the pace of wearable technology change.
Better batteries ultimately mean better wearables. And as lithium-ion batteries go, so will wearable devices. Expect the volume of consumer wearables to increase commensurate with improved battery technology.