If the people at Stanford University have their way, heart transplant batteries may become a thing of the past. With today’s technology, heart transplants are battery powered. And, just like any other battery, the batteries in heart transplants tend to run low over time, requiring surgery to replace them. Now, Stanford has announced a novel technology which should allow the batteries to be recharged from the outside of the body, reducing or eliminating the need to replace them.
Scientists used to believe that the high frequency fields -needed to deliver power wirelessly to the heart implants – could not penetrate the human body deep enough to successfully recharge the devices. Because an antenna on the implant is used to receive the recharge, the low frequency recharging method would have required an antenna which was too large to be implanted into the body. Scientists were stumped until they realized that an alternating high frequency electric and magnetic field may just hold the answer.
The team at Stanford is using a field which cycles at 1.7 billion cycles per second, sending power directly though the body to the coiled receiving antenna on the implant. The breakthrough allowed scientists to increase power delivery by a factor of 10. Current tests have shown that an implant 5 centimeters below the skin could receive as much as 50 microwatts to a millimeter radius coiled antenna. This proof of concept testing is not nearly a fully functional technology at this time, but it does show a lot of promise.
One of the benefits of the technology will be that it does not require a particular orientation for the antenna to receive charge. This gives the obvious implication that the implanted devices may one day be able to recharge while on the go, instead of requiring a person to come into a doctor’s office and sit for hours.
The implications for this technology obviously may spread far beyond just heart implants. At the moment, wireless recharging of electronic devices is a dream in general. With all the wires which connect the word, from wires to recharge cell phones and lap tops, to wires which carry power across cities and towns, one does get the sense that a true wireless revolution will soon be upon us. In fact, recent products at the Las Vegas consumer electronics expo have included wireless power delivery technologies, though none have taken hold in the marketplace as of yet.
The breakthrough in by the Stanford team is truly amazing. Using radio waves to transmit the power to the antenna, the team sent power to an implanted cube which was just an eighth of a millimeter in radius. This is small enough to fit on the head of a pin.
Possible devices which could benefit from the technology, once it is fully developed, include such implanted devices as pacemakers, cochlear implants and drug pumps. The findings were published in the journal Applied Physics Letters, with assistant professor of electrical engineering at Stanford Ada Poon as senior author.
Speak Your Mind