Implanted medical devices may no longer need to be charged

By Sharin Hussain via SWNS

Implanted medical devices such as pacemakers may no longer need to be charged, suggests new research.

The study finds that the batteries for medical devices such as a pacemaker or neurostimulators, could potentially operate on the person’s own oxygen.

A group of Chinese scientists create an implantable battery that runs on oxygen in the body.

Corresponding author Professor Xizheng Liu, of Tianjin University of Technology, said: “When you think about it, oxygen is the source of our life.

“If we can leverage the continuous supply of oxygen in the body, battery life won’t be limited by the finite materials within conventional batteries.”

The study, published in the journal Chem, found that the proof-of-concept design can deliver stable power and is compatible with the biological system in rats.

Researchers made a safe and efficient battery by using electrodes out of a sodium-based alloy and nanoporous gold, a material with pores thousands of times smaller than a hair’s width.

Gold has been known for its compatibility with living systems, and sodium is an essential and extensive element in the human body.

The electrodes undergo chemical reactions with oxygen in the body to produce electricity.

The battery was protected by being encased within a soft and flexible porous polymer, a class of multi-dimensional penetrable network materials.

The researchers implanted the battery under the skin on the backs of rats and measured its electricity output.

Two weeks later, they found that the battery can produce stable voltages between 1.3V and 1.4 V.

Although the output is insufficient to power medical devices, this experiment shows that it potentially could.

They also analyzed inflammatory reactions, metabolic changes, and tissue regeneration around the battery.

The rats showed no apparent inflammation. Sodium ions, hydroxide ions, and low levels of hydrogen peroxide, were easily metabolized by the body and did not affect the kidneys and liver.

The rats healed well after implantation, with the hair on their back completely regrown after four weeks.

Researchers were shocked to see that blood vessels also regenerated around the battery.

The team plans to up the battery’s energy delivery by exploring more efficient materials for the electrodes and optimizing the battery structure and design.

The battery is easy to scale up in production and choosing cost-effective materials can further lower the price. The team’s battery may also find other purposes beyond powering medical devices.

Prof Liu added: “Because tumor cells are sensitive to oxygen levels, implanting this oxygen-consuming battery around it may help starve cancers. It’s also possible to convert the battery energy to heat to kill cancer cells.

“From a new energy source to potential biotherapies, the prospects for this battery are exciting.”