Ultrafast charging 3D thin-film battery for micro-storage

Introduction

Imec is developing a completely new 3D thin-film battery architecture that recharges ultrafast. These small batteries are intended for microsystems such as implants, sensors and ‘smart cards’.

Our solution

Imec is developing is a 3D thin film battery in which the thin-film stack is coated over a micro-structured substrate instead of on a planar substrate. This method enables very thin film electrodes and electrolytes (a few hundred nanometers thick) and thus small batteries, while achieving energy densities comparable with current-day battery technology.

Due to their small size, these batteries have a small actual capacity but they are quickly recharged or topped up due to the fast movement of charges through the thin film stack. The advantage of the thin-film battery concept is that electrolyte materials with relatively low ionic conductivities can be used (>1E-7 S/cm).

We have developed novel solid thin-film electrolytes of 100nm in thickness which can be coated conformally over high aspect ratio 3D electrodes. We have demonstrated a proof-of-concept with both cathodes and anodes coated over a dense micropillar array.

Applications

• Small storage systems for IoT, sensor systems, implants, smart cards and power on chip.