MIT researchers use a new electrolyte to improve implant battery life

Pacemaker batteries typically last 5 to 10 years, and even less if they require high-voltage functions such as defibrillation. But for such a battery, Gao said, the technology is considered mature and “there have been no major breakthroughs in fundamental cell chemistry in the past 40 years.”

The key to the research group’s innovation is a new type of electrolyte; it is the material that is found between the two electric poles of a battery, namely the cathode and the anode, and allows the charge carriers to pass from one side to the other.

Using a new liquid fluorinated compound, the research team discovered that they could combine several cathodic and electrolyte functions in a single compound, called a catholyte. This saves a lot of weight over ordinary primary batteries, Gao said.

In fact, there are materials other than these new compounds that could theoretically play a catholyte-like role in high-capacity batteries. However, according to Gallant, the material has a lower internal voltage that is incompatible with the rest of the materials in conventional pacemaker batteries, the type known as CFx.