Advancements in medical technology are resulting in increasingly smaller devices designed to be implanted in or adhered to the body – everything from neuromodulation devices and implanted sensors to small wearables such as smart contact lenses and orthodontic devices. Because many of these devices are implanted with catheters winding through arteries and veins, they must be small, customizable, and safe.

Ilika’s Product Commercialization Manager, Denis Pasero, says achieving safe, miniaturized devices depends on battery technology. “Our solid-state Stereax micro-batteries are designed to address the needs of these next-generation devices, and we work closely with our customers to customize them in terms of size and shape,” Pasero says. “A battery is a core operating function, and too often a device is designed and then they consider what battery will power it. It’s best when we work closely with designers in the early stages, so they know there are more options than standard lithium-ion (Li-ion) batteries. We create customized batteries for the device rather than the device being designed around standard options.”

Traditional cylindrical or button batteries can be as small as 2mm, fine for many consumer devices, but far too massive for medical devices with micron-level tolerances. Pasero says batteries can be manufactured as thin as 100µm, and customization can make them long and thin, flat, square, round, circular, or irregularly shaped.

“This is one of the beauties of solid-state battery technology. Because it has no toxic liquids, is free of lithium, and is biocompatible, you need minimal packaging and gain flexibility for customization,” Pasero says. “In addition, the batteries are self-sustaining, which is important because when you have a small battery you will generally have small energy. But, you need it to store energy for years and not have current leak away.”

One of the issues with conventional Li-ion batteries is they degrade faster than solid-state batteries, which have ceramic parts next to each other so current leakage is small and energy storage is efficient. Stereax micro-batteries use ceramic films in the micron range, enabling currents to quickly go in and out for charging and use, Pasero explains. They can be recharged wirelessly or by energy harvested from the body, enabling medical devices to work at their full potential for a long time.


About the author: Elizabeth Engler Modic is editor of Today’s Medical Developments. She can be reached at 216.393.0264 or

Battery specifications

  • Stereax M50/M300 micro-batteries
  • Ultra-thin form factor, M50 is as low as 150µm, M300 is less than 1mm
  • 3.6mm x 5.6mm footprint
  • Stackable for increased energy density (M300 is the 6-stack version of M50)
  • High capacity: M50 is 50µAh, M300 is 300µAh
  • All solid-state construction, no leakage of toxic liquid
  • Fast charge (a few minutes)
  • High cycle count
  • Long shelf life
  • Combine in various formats to increase energy to mAh level