3D Microbatteries

Applications

Microbatteries can be used to power a wide variety of small systems from simple sensors to systems with integrated ultrahigh density packaging (i-UHD). This technology is a "bottom-up" approach to battery fabrication that simultaneously uses repulsive and attractive forces between colloidal-scale ion storage materials to self-organize complete bipolar devices. 

Problem Addressed

Conventional lithium-ion batteries have a laminated design and limited energy density. This design uses a colloidal self-organization approach whereby repulsive forces between dissimilar materials are used to form in-situ­ electrochemical junctions in dense particle arrays, while attractive forces between like materials are used to form continuous electronically conductive networks. The system tends toward a thermodynamic ground state where co-continuous interpenetrating networks of cathode and anode create a two-dimensional or three-dimensional interpenetrating electrode battery. 

Technology

This invention is founded on a micro-fabricated structure of 3D electrode array. It proposes an integrally packaged, solid-state lithium rechargeable microbattery with a 3-dimensional interpenetrating-electrode internal architecture. The microbatteries are fabricated either  through sputtering or colloidal scale self-organization and have the capability for outer package aspect ratios of less than 5:1 for maximum to minimum dimensions and active materials packing fraction of >75% in a 1mm3 volume, which  allows them to be used in i-UHDs. . The proposed approach will use currently available and proven cathode and anode materials, but will allow drop-in of higher energy or higher rate active materials as they are developed in the future.

Advantages

  • Increases energy density
  • Increases charge and discharge rate