https://www.epo.org/en/news-events/press-centre/press-release/2018/452062

The power behind lifesaving biomedical devices: Esther Sans Takeuchi named European Inventor Award 2018 finalist

24.04.2018

in Press release

US inventor Esther Sans Takeuchi nominated for European Patent Office (EPO) prize for developing the lithium/silver vanadium oxide battery
Her battery has enabled the widespread adoption of implantable cardiac defibrillators (ICDs), increasing comfort and security for those using the device
EPO President Battistelli: "Sans Takeuchi's innovative work in energy storage and power sources is enabling lifesaving technologies that benefit millions of patients ."

Munich, 24 April 2018 - Patients at high risk of heart attack often receive pacemakers, and more frequently today, sophisticated implantable cardiac defibrillators (ICDs). These devices detect and correct irregular, potentially fatal, heart rhythms, thereby safeguarding millions of lives. The fitting of these devices, and the replacement of the batteries that run them, involves surgery, with its attendant hazards. US inventor Esther Sans Takeuchi has developed a battery with a nearly fivefold increase in lifespan that greatly reduces the number of times an ICD wearer might have to go through such an operation. This has led not only to an advance in battery chemistry but wider acceptance of life-saving ICDs and a significant improvement in patient well-being.

For this achievement, Esther Sans Takeuchi has been nominated as a finalist for the European Inventor Award 2018 in the category "Non-EPO countries". The winners of this year's edition of the EPO's annual innovation prize will be announced at a ceremony in Paris, Saint-Germain-en-Laye, on 7 June 2018.

"Sans Takeuchi's innovative work on energy storage and power sources is enabling life-saving technologies that benefit millions of heart-failure patients," said EPO President Benoît Battistelli, announcing the European Inventor Award 2018 finalists. "Her developments in the field of battery technology have also made her one of the most prolific US women inventors."

The power behind implantable cardiac defibrillators

Materials scientist and chemical engineer Esther Sans Takeuchi's career has been dedicated to electrochemistry and more specifically battery technology. Her work has focussed on getting the most power and longest life out of batteries as possible, and the results of her efforts have had a very wide impact. Sans Takeuchi's invention of the compact lithium/silver vanadium oxide battery enabled the widespread introduction of modern ICDs. With about 300 000 of these devices implanted each year worldwide, they are quite literally life-savers - using a high-voltage shock to reset the heart and prevent sudden death in high-risk patients who are susceptible to cardiac arrest.

From 1980, when the first defibrillator was implanted, through the mid-1980s when the technology received FDA approval in the US, issues of size and especially battery life were potentially jeopardising successful implementation. The batteries used in the first ICD designs were only able to function for 12 to 18 months and could result in heart patients having to undergo frequent and potentially risky surgery for battery replacement. The challenge, explains Sans Takeuchi, was to develop a battery that was small enough to implant, provided a significant lifetime, yet offered very high power to deliver sufficient energy so the device could provide therapy to the patient:

"The defibrillator battery must deliver 1 million times more power than a pacemaker battery," Sans Takeuchi says. "So we knew we needed a different battery. It could not be simply a pacemaker battery repeated a million times. It had to be a new chemistry."

Invented when she was a battery research scientist at medical device manufacturer Greatbatch, her solution was to turn to the chemical and electrical properties of three unique metals. Selecting lithium as the anode for her new battery due to its high energy density was almost certain: the metal had proven its reliability since company founder Wilson Greatbatch developed the first lithium-anode pacemaker battery nearly a decade earlier. However, for her battery's cathode Sans Takeuchi needed a material that would draw out as much current and voltage from the lithium as possible and sustain this over a long battery life. Her answer was a silver vanadium oxide compound. Vanadium provided long life and high voltage. The silver delivered the high current necessary for ICDs' shocks to reset the heart.

Widespread adoption

Sans Takeuchi's lithium silver vanadium oxide ("Li/SVO") battery extended the power-source lifetime for ICDs to around five years and played an important role in their widespread adoption beginning in the late 1980s. The battery technology was first employed in an implanted ICD in 1987 and commercialised by Greatbatch. which has since been renamed Integer Holdings, and now manufactures ICD batteries based on the invention and licenses the technology to two other battery suppliers. Li/SVO batteries remain the most commonly used batteries in ICDs and have since been incorporated as one of the leading power sources for a broader class of implantable cardiac rhythm management devices, which includes devices that combine ICD, pacemaker and other heart monitoring functions.

Sans Takeuchi's Li/SVO batteries now dominate the market for implantable cardiac defibrillators, which today is worth nearly $5 billion in the US alone - with more than 10 000 implants every month there. The invention has contributed substantially to making the life-saving ICD technology an attractive medical option for millions of patients.

The use of patents was a deliberate strategy on the part of the company from the very beginning: "We were a small group. So we knew in order to remain competitive we had to be clever," says the inventor. "So we developed a strategic approach to patents where we obtained patents to cover the technology that we developed, and patents to cover other possible solutions to solve the problem."

Sans Takeuchi also played an active role in numerous additional improvements of the system that optimised it as a high-rate ICD battery. Two of her other patented inventions added carbon monofluoride to the silver vanadium oxide in the cathode to develop a related, smaller battery that enabled the development of more compact ICDs that are safe to use despite their reduced volume. Sans Takeuchi's patents are also behind batteries powering neurostimulators, pumps and many other implanted devices.

Talented, focused, prolific

The daughter of Latvian emigrants, Esther Sans Takeuchi credits her parents for instilling in her a strong work ethic from a young age and for awakening her interest in science. "My father did not believe that school did an adequate job of teaching mathematics and would teach me algebra in the evening," says Sans Takeuchi. "Both my parents felt that a scientific education was extremely important." Indeed, Sans Takeuchi's academic programme provided her with a rich background for her later professional work. She earned a bachelor's degree in chemistry and history from the University of Pennsylvania in 1975 and a PhD in organic chemistry from Ohio State University in 1981. She then served as postdoctoral research associate in electrochemistry, first at the University of North Carolina at Chapel Hill from 1982 to1983, and then at the State University of New York at Buffalo from 1983 to 1984. Directly thereafter she found a professional home as scientist, chief scientist, then Director of Research and Development of Battery Research & Development at Greatbatch Inc.

She returned to her academic roots in 2007 to take a professorship position at the State University of New York at Buffalo. Since 2012, she is the SUNY Distinguished Professor in the Materials Science and Engineering department at Stony Brook, New York, as well as Chief Scientist of the Energy Sciences Directorate at Brookhaven National Laboratory.

With over 150 US patents and 39 European patents to her name, Sans Takeuchi is credited with being one of the most prolific US woman inventors. She was awarded the 2008 National Medal of Technology and Innovation by US President Barack Obama for her invention of the Li/SVO battery, and in 2011 she was inducted into the Inventors Hall of Fame. In 2013, she received the E.V. Murphree Award in Industrial and Engineering Chemistry from the American Chemical Society. She is a member of the US National Academy of Engineering, a Fellow of the American Institute for Medical and Biological engineering, and a Fellow of the Electrochemical Society, for which she served as President from 2011-2012.

Additional resources

Download our app " Innovation TV " to your smart TV and watch video portraits of all finalists on your TV screen

View the patents: EP1768203, EP1215175, EP1816692 EP1156541, EP0630065 , EP0618630

Implantable inventions

The first implantable pacemaker (1958) and cardiac defibrillator (1980) helped usher in a world where medical devices can be located inside the human body to improve life expectancy and well-being. The most commonly used implants - eye lenses and ear tubes - might pale in comparison to what science fiction has promised but can often have life-changing results. For further examples of how implants can change lives look to the customised pacemakers developed by a Dutch team nominated for the 2007 European Inventor Award. A team of French scientists, who were award finalists in 2014, have developed an implantable fuel cell to power pacemakers which runs on glucose from the patient's own blood. Also finalists in 2014 were Austrian electrical engineers Erwin and Ingeborg Hochmair who invented cochlear implants to restore hearing to hundreds of thousands of patients.