Somebody in my family has a pacemaker, and is fully dependent on it. I can confirm this part: > Easier to replace the whole pacemaker than the battery unfort

Somebody in my family has a pacemaker, and is fully dependent on it. I can confirm this part: > Easier to replace the whole pacemaker than the battery unfortunately, this statement: > As for how long the cells last, modern Lithium Thionyl Chloride cells last 5-10 years depending on the pacemaker. They probably actually last longer, manufacturers are pretty conservative with lifetime estimates. only partially applies in this case. That pacemaker has a lot of work to do (stimulate every single heart beat), and depending on the quality of the electrodes on the heart, and the cables that lead to them, some needed to be replaced after two or three years. If one lasts 7 years, that is a very welcome respite, but quite the exception. That said, pacemakers have come a long way. The first on that this person had implanted had a fixed beat. The current generation has sensors for oxygen saturation and movement, and be configured and maintained through a wireless interface, they log unusual events etc.