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Coin sized battery can last 50 years without recharge – coming in 2025

livescience.com

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Re: Coin sized battery can last 50 years without recharge – coming in 2025

#11

Post by talldrinkofwhat »

snailmailman wrote: post #2

100 microwatts isn’t much. I’m curious how long other comparable batteries would last if you were only drawing 100 microwatts from them. I’m curious what you could run on that little power. But I guess something a bit larger could probably be batteries in a smoke alarm, or other home security sensors? Idk how much power those draw but if it’s just making a WiFi ping sporadically it probably isnt much.

P=IV (power = current * voltage)

Lipos -> 3.7V nominal once you're in the meat of it. 100uW -> 27uA @3.7V, which is a __VERY__ generous current budget with modern microcontrollers and effective use of sleep modes.

AAA Cells -> 1200mAH @27uA -> 5rs

AA Cells -> 2200mAH @27uA -> 9.3yrs

C Cells -> 9000mAH @27uA -> 38yrs

Then just remember that this thing is smaller than all of those, has no self discharge which typically steals 2-3% of the battery capacity year-over-year, and that with lipo's you can't use the last chunk of nameplate capacity due to precipitous voltage drop at the end of the discharge curve.

Re: Coin sized battery can last 50 years without recharge – coming in 2025

#13

Post by z_ack »

Clickbait BS:

"If approved for use in devices like smartphones, future generations of the battery would ultimately remove the need to ever charge them, company representatives said."

The battery is around a cube centimetre , a microampere is 1 / 1'000'000 of Ampere (A), a smartphone needs between 2 and 3.5 Ah , even a single LED needs milliamperes ( 1 / 1000 of A), you can do the math. Still this crap is reposted again, again and again. At this point I'm sure, it is part of a campaign to deceive investors. Two companies tried to collect funds for this kind of batteries, one simply disappeared, the other is under investigation for fraud:

https://www.youtube.com/watch?v=5M5MF6KE-jY

Anyway, what is the point of a 50 years battery to put inside devices people throw away after 4-5 years, top ? To produce more nuclear wastes in a world where people can't build nuclear dump sites ? It's hilarious if you think about it: apparently the same people that are against nuclear power plants, a technology able to save the planet reducing the fossil fuels consumption, find acceptable to put a nuclear source near their crouch to avoid phone recharges.

Re: Coin sized battery can last 50 years without recharge – coming in 2025

#14

Post by SOLAR_FIELDS »

snailmailman wrote: post #2

100 microwatts isn’t much. I’m curious how long other comparable batteries would last if you were only drawing 100 microwatts from them. I’m curious what you could run on that little power. But I guess something a bit larger could probably be batteries in a smoke alarm, or other home security sensors? Idk how much power those draw but if it’s just making a WiFi ping sporadically it probably isnt much.

You had me until WiFi ping. One thing you learn doing electronics with batteries pretty quickly is that WiFi just destroys battery. Even just turning the radio on (which you must do for any low power device, they are idling in deep sleep otherwise) is going to cost you orders of magnitude more power than anything non radio related. The most efficient devices that ping something on battery use some alternative low power protocol that isn’t full WiFi. The story around BLE is significantly better but also the rise of thread and Matter makes these alternative ways of communication more viable these days.

Re: Coin sized battery can last 50 years without recharge – coming in 2025

#15

Post by phil294 »

z_ack wrote: post #13

Clickbait BS: "If approved for use in devices like smartphones, future generations of the battery would ultimately remove the need to ever charge them, company representatives said." The battery is around a cube centimetre , a microampere is 1 / 1'000'000 of Ampere (A), a smartphone needs between 2 and 3.5 Ah , even a single LED needs milliamperes ( 1 / 1000 of A), you can do the math. Still this crap is reposted aga…

> apparently the same people

The only thing these two groups of people have in common is that you don't like them. I fail to see any correlation here whatsoever.

Re: Coin sized battery can last 50 years without recharge – coming in 2025

#16

Post by gus_massa »

phil294 wrote: post #15
z_ack wrote: post #13

Clickbait BS: "If approved for use in devices like smartphones, future generations of the battery would ultimately remove the need to ever charge them, company representatives said." The battery is around a cube centimetre , a microampere is 1 / 1'000'000 of Ampere (A), a smartphone needs between 2 and 3.5 Ah , even a single LED needs milliamperes ( 1 / 1000 of A), you can do the math. Still this crap is reposted aga…

> apparently the same people The only thing these two groups of people have in common is that you don't like them. I fail to see any correlation here whatsoever.

I agree with both of you.

Each year it's a different technology. A time ago it was radioactive Carbon, this is radioactive Nickel, and I have the feeling I forgot another variant posted a few years ago... But for some misterious reason, all of then promise "100 microwatts".

Re: Coin sized battery can last 50 years without recharge – coming in 2025

#17

Post by kedikedi »

gus_massa wrote: post #10
kedikedi wrote: post #7

Earlier quoted context omitted.

There’s also the self discharge aspect of things: cells lose energy even if you draw no current at all. This is dependent on many things including chemistry, quality, buildup, temperature and whatnot. I am not including lithium batteries (not bare cells) which need to have some kind of protection circuitry that also draws a bit of power.

It's not a chemical battery. The energy comes from the nuclear desintegration of radioactive nickel. So the charge is inmmune to most of the usual problems. On the other hand, I don't know how strong are the layers that aborb the radiation and cretes the electricity.

Ah, you’re right! I was talking about the “comparable” batteries, assuming them being chemical batteries
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