Flexible, solid electrolyte-based lithium battery composed of LiFePO4 cathode and Li4Ti5O10 anode for applications in smart textiles

TL;DR

This paper presents the development of a flexible, solid electrolyte-based lithium battery with LiFePO4 cathode and Li4Ti5O10 anode, suitable for integration into smart textiles, emphasizing environmentally friendly fabrication and practical textile applications.

Contribution

It introduces a novel flexible lithium battery with a solid PEO electrolyte, optimized electrode composites, and demonstrates its integration into smart textiles with environmentally friendly manufacturing.

Findings

Battery is flexible and stretchable, suitable for smart textiles.

Electrodes and separator fabricated using aqueous solutions.

Successful weaving of battery strips into textile fabric.

Abstract

Here we report fabrication of flexible and stretchable battery composed of strain free LiFePO4 cathode, Li4Ti5O10 anode and a solid poly ethylene oxide (PEO) electrolyte as a separator layer. The battery is developed in a view of smart textile applications. Featuring solid thermoplastic electrolyte as a key enabling element this battery is potentially extrudable or drawable into fibers or thin stripes which are directly compatible with the weaving process used in smart textile fabrication. The paper first details the choice of materials, fabrication and characterisation of electrodes and a separator layer. Then the battery is assembled and characterised, and finally, a large battery sample made of several long strips is woven into a textile, connectorized with conductive threads, and characterised. Within this paper, there are two practical aspects of battery design that we have investigated in details: first is making composites of cathode/anode material with optimized ratio of conducting carbon and polymer binder material, and second is battery performance including cycling, reversibility, and compatibility of the cathode/anode materials. Finally, when casting electrodes and separator layer we mostly focused on using aqueous solutions instead of organic solvents in order to make the fabrication process environmentally friendly.