Biobateria produces clean electricity for days

Simple, small and efficient, the biobattery is ideal for the "internet of disposable things". [Image: Sean Choi]

Bio-battery or bio-cell?

The microbial batteries have been around for some time, but the emergence of the Internet of things can make them return to the headlines.

The good news is that bio-battery technology is not at a standstill, which has made them cheaper and more efficient.

"This new technique, built in the form of a small, compact, disposable package, at a low price, can cheaply connect things to work for a programmed period and then be discarded promptly," said Professor Seokheun Choi of Binghamton University, United States.


In fact, the new biobattery is in the middle between a battery and a microbial fuel cell - a bio-hybrid battery would be a good name.

The team had already developed paper biobanks and full-fledged microbial fuel cells .

"The bio-mass we developed this time is a kind of combined technique of these two, the pot life was significantly increased using solid-state compartments, but the device is a form of battery without complicated energy-consuming fluid-feeding systems and what typical microbial fuel cells require, "said Choi.

In other words, the team managed to get rid of the more complex part of the system.

"We have revolutionized the liquid anolyte, the salt bridge and the cathode compartment in solid counterparts, increasing their densities and enabling their slow and continuous reactions. In addition, the solid phase components will make the device suitable for miniaturization, integration and operation with the internet applications of solid-state things, "wrote the team.

Hybrid microbattery produced a maximum power density of 4 μW / cm 2 (0.3 mW / cm 3) and a current density of 45 μA / cm 2 (0.37 mA / cm 3) after 96 hours of operation, while the earlier, more complex, liquid-based version stopped generating power after 4 hours.

Bibliography: A solid phase bacterium -based biobattery for low-power, low-cost, internet of Disposable Things Maedeh Mohammadifar, Seokheun Choi Journal of Power Sources Vol .: 429, Pages 105-110 DOI: 10.1016 / j.jpowsour.2019.05. 009