New Type of Battery Can be Charged Using Dirt

Researchers at Northwestern University have developed a new fuel cell that uses naturally occurring soil bacteria to generate electricity for underground sensors.

The device is about the size of a paperback book and is designed to power low-energy systems such as agricultural monitoring sensors without relying on batteries or solar panels.

Precision agriculture often depends on buried sensors that monitor soil moisture, nutrients, and contaminants.

Keeping those sensors powered can be difficult in remote locations because batteries need replacement and solar panels can become covered in mud or stop working at night.

The new fuel cell is designed to avoid both problems by drawing power directly from microbes already living in the soil.

Microbial fuel cells have existed in concept for more than a century. They generate electricity by capturing electrons released by bacteria as they break down organic matter. Those electrons move between the anode and the cathode, creating a usable electrical circuit.

The Northwestern team said previous versions often struggled with low output and inconsistent performance, especially in dry conditions.

Researchers spent two years testing four different structures before selecting a design that positioned the anode and cathode at right angles.

The anode, made from carbon felt, sits flat below the soil surface.

The cathode stands upright, with its top level with the ground to allow oxygen flow, while the lower section remains moist underground.

A 3D-printed cap protects the system from dirt while allowing airflow.

Part of the cathode was also waterproofed so it could continue working during floods.

According to the study, the fuel cell continued operating through dry periods and flooding.

It generated 68 times more power than its own sensors required.

The attached sensors measured soil moisture and could also detect touch, which researchers said may help monitor animals moving through fields.

The system also included a small antenna that wirelessly transmitted data using reflected radio signals.

Researchers said the technology is intended for small sensors rather than larger electronics.

George Wells, one of the study’s senior authors, said the goal is to capture small amounts of electricity for practical low-power applications.

The team said all parts can be purchased from hardware stores.

They have also published designs, instructions, and simulation tools online so others can reproduce or adapt the technology.

Their next goal is to build a version using materials that naturally break down in soil.

Fun fact. The human body contain 3 times more energy then a lithium battery. And can power using it as well. Why haven’t we tried using it ? Ever thought of that ?

That doesn’t mean it can work to Power things. While it is true that naturally occurring conduction exists but it cannot be applied instead of a commercial battery due to its nature and the variables that have to be taken into account for electrical usage