Together with his colleagues, Sokhin Choi created a fully autonomous biopile for several weeks. It uses three types of bacteria, each located in separate compartments on top of each other.

How does it work

Energy production takes place in several stages.

Photosynthetic bacteria produce organic food that will become food for other bacterial cells. At the bottom – electricity-producing bacteria and intermediates produce some chemicals to improve electron transfer,
Choi explains.

The inventor compares his 3-by-3-centimeter batteries with Lego bricks. They can be combined in different ways, depending on the electrical power required for the sensor or device.

The ultimate goal of these studies, the scientist calls minimizing battery size – he wants to make them very small.

My ultimate goal is to make the device really small. We call it “smart dust,” and a pair of bacterial cells will generate enough energy to work. Then we can distribute it where needed,
– said.

The professor also wants to create a floating and self-healing version of the battery to automatically repair damage from potentially harsh conditions.

So far, the technology doesn’t look very encouraging. A few things remain unclear:

• It is unclear how much energy such a battery produces and how many individual units are needed to power certain devices, thus how portable they are.
• What to do when the battery is low? It is absolutely impossible to charge it like a normal battery. You will likely need some kind of “bacteria transplant” provided you can continue to use the old case. It produces a lot of waste if it becomes unusable because it’s not a good idea to replace batteries with new ones every few weeks.
• If we talk about “smart dust”, which is the final stage of development, it is not clear how it is proposed to collect energy from such small generators “scattered” on the surface.