Development of a "advanced conductive mesh" that improves the adhesion and conductivity of silicon-based active materials in next-generation lithium-ion batteries

I-PEX Inc. (Headquarters: Kyoto City, Kyoto Prefecture, Representative Director and President: Reiji Konishi, hereinafter I-PEX) is developing an advanced conductive mesh that will contribute to enhancing next-generation lithium battery performance by improving the adhesion and conductivity of silicon-based active materials.

Actual samples of this technology and technical explanation materials will be exhibited at the I-PEX booth (6F No. 15) at the 66th Battery Symposium Co-exhibition, to be held at Winc Aichi in Aichi Prefecture from Tuesday, November 18th to Thursday, November 20th, 2025.

Recently, in order to increase the capacity of next-generation lithium-ion batteries, it is expected that silicon-based active materials, which have a theoretical capacity more than 10 times that of graphite-based active materials, will be used. However, silicon-based active materials undergo a volume change of approximately four times that of graphite-based active materials when discharged and charged. This means that copper foil, which is generally used as a negative electrode current collector, has an issue where the active material expands and contracts during repeated charging and discharging of the battery, causing it to peel off from the current collector. This has prevented progress in the use of silicon-based active materials.

To solve this problem, I-PEX has utilized the surface treatment technology and know-how it has cultivated through the integrated production of connectors in Connectors Business to develop a "advanced conductive mesh" with a three-dimensional surface structure and voids, made by surface-treating nonwoven fabric with copper for the anode and aluminum for the cathode.

The advanced conductive mesh is expected to improve issues such as the adhesion and conductivity of silicon-based active materials in next-generation lithium-ion batteries, thereby contributing to improved battery performance.

In this test, a lithium-ion battery with an anode containing over 65% silicon was prototyped using a "advanced conductive mesh" made by plating copper on nonwoven fabric, and performance was compared after 300 charge/discharge cycles. In comparison with the reference copper foil, it was confirmed that the "advanced conductive mesh" improves cycle performance by holding the active material within the metallized nonwoven fabric fibers. It was also confirmed that the battery has good compatibility with solvent-based binders.

The advanced conductive mesh will be exhibited at the "66th Battery Symposium Exhibition" to be held at Winc Aichi from Tuesday, November 18th to Thursday, November 20th, 2025.

I-PEX has developed the "RENERATH" series of battery storage systems, which reuse used lithium-ion batteries from electric vehicles. By combining reused batteries with IoT technology, the company aims to provide a sustainable, safe, and secure energy supply through storage batteries. As a new initiative in energy solutions, the company is currently developing advanced conductive mesh for next-generation lithium-ion batteries.

I-PEX stands for “Innovative Product development & Engineering solutions eXpert” providing value in the form of inspiration and astonishment in the global marketplace. The company was founded in 1963 as Dai-ichi Seiko, a precision mold manufacturer, and has since produced numerous world-firsts and unique products and solutions. I-PEX currently operates in five business fields: Connectors, Contract Manufacturing (Automotive Components & Electronics Components), Molds & Equipment, MEMS Foundry, and Energy Solutions. By delivering the sharpest tip to the world, we will contribute to exciting value-creation in the digitalized society by working globally with every customer who opens up the new era.