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by adversaryIdiot 1023 days ago
i wonder why the battery cant be charged wirelessly
2 comments

Interesting idea. Current battery in the device (I looked it up) is:

Chemistry: Lithium carbon monofluoride

Voltage: 3.3 V, open circuit

Rated capacity: 1 Amp-hour

Self-discharge rate: <1% per year

Its a tiny non-rechargeable battery presumably carefully picked for safety and very slow usage over several years.

I suppose the main barrier to wireless charging of implant batteries would be heat - wireless charging generates heat. And when something goes wrong with wireless charging it can generate a lot of heat. So I guess its risky? But then surgery to change a battery is also a significant risk.

Also I guess someone would have to go through the long process with the FDA of getting it all approved, whereas (at a guess) people designing implants try and use already-proven components and techniques where they can to make approval more likely.

Could also just be a battery lifetime issue? 8 years is a long time. If they made it rechargeable, they might still need to replace it every 8 years anyway just for safety.
Heat would be an issue but if you do it a little bit at a time might be ok.