Thinner Current Collector Primers for Battery Electrodes

Current collector primers are thin functional layers between the metal foil and the electrode coating. Their role depends on the electrode technology. In today’s LFP cathodes, very thin primer layers are already used to improve the electrical contact between current collector and electrode coating. In some cases, these layers are already below 1 µm.

For dry-coated electrodes, the task becomes broader. Here, the primer layer needs to provide electrical connection, adhesion between foil and dry electrode layer, and process robustness during calendering. As a result, dry-coating primers are often significantly thicker and can be well above 1 µm. This creates a simple question: Can primer coatings become thinner while still maintaining conductivity and adhesion?

## Why eGraphene Is Interesting for Primer Coatings

eGraphene combines high electrical conductivity with a two-dimensional flake geometry.

This matters because 2D flakes can form conductive networks at low loading levels. In a primer coating, this can reduce the amount of conductive additive required to achieve electrical performance.

That creates more room in the primer formulation for binder. A higher binder share can support adhesion, while eGraphene maintains conductivity. This opens the possibility of primer layers below

500 nm that still supports both key functions: Low resistance and electrode adhesion.

## Why This Matters

Reducing primer thickness is not only a material question. It can influence electrode design and manufacturing economics. Thinner primer layers mean:

• less overall material use

• less inactive thickness

• potentially lower coating costs

• better compatibility with high-energy electrode designs

This is especially relevant for dry-coated electrodes, where primer layers may become an important part of the electrode architecture. The goal is not simply to add another coating. The goal is to achieve the required interface function with as little material as possible.