100 microwatt per battery, but the battery itself is tiny, 15x15x5 mm. Average cellphone battery is ~ 30x60x5 mm, so you can fit 8 cell there. Is it enough to power a phone?
0.8 watts? Honestly, I think it gets closer than I was expecting. (edit: millli/micro, messed it up. This is a tiny amount of power. Needs to get near that 1W they are aiming for to be useful).
Searching around, I see estimates of 5-20 watts when fast charging, and 1-2W in standby mode. The article says they are aiming for 1W in the next couple of years, which can probably do it. However, it's not clear what peak output it. You would probably use half the space for a normal battery and half for this power source, so that the phone can charge itself but also have a higher output when it's needed.
It probably doesn't even need to provide all the power. Imagine if your phone would trickle charge wherever you were. If you're watching netflix you might run out of battery and have to charge. If you aren't using it much, even if the output of these things can't keep up, the battery could last days or a week on a charge before eventually running out.
According to this article, an average smartphone uses 2W when in use. That number will largely be dependent on the screen and SOC, which can be turned off or be placed in a lower power state when the phone isn't actively being used. (The 5W - 20W figure is for charging a phone.)
With 8 of these cells, you'll have 800μW, or 0.0008W, and you need 2W. You will need to add a few more batteries... About 19,992 more. If 8 of these batteries are about the same size as a regular smartphone battery, you will need the equivalent of 2,500 smartphone batteries to power just one phone.
Too bad they don't say how much the new batteries weigh! It would have been fun to see...
If we ballpark it and assume something the size of a regular smartphone battery is 50g (1.7 oz), then our stack of 20,000 of these new batteries could be about 125kg (275 lbs).
I won't be replacing any of my batteries just yet.
Sounds very similar to the old Soviet pacemakers with radioisotope batteries. After the collapse of the Soviet Union, records about them got lost and so a bunch of people have been buried with pretty radioactive stuff in their chest. I don't think we (as developed societies) are going to take that risk for some phone batteries...
I noticed, by reading the article, that Nickel 63 decays to Copper 63 which is stable.
"Betavolt further states the battery is environmentally friendly. “After the decay period, the nickel 63 isotopes become a stable isotope of copper, which is non-radioactive and does not pose any threat or pollution to the environment,” the company explains. “Therefore, unlike existing chemical batteries, nuclear batteries do not require expensive recycling processes.” "
Here's the summary for the wikipedia article you mentioned in your comment:
Naturally occurring nickel (28Ni) is composed of five stable isotopes; 58Ni, 60Ni, 61Ni, 62Ni and 64Ni, with 58Ni being the most abundant (68.077% natural abundance). 26 radioisotopes have been characterised with the most stable being 59Ni with a half-life of 76,000 years, 63Ni with a half-life of 100.1 years, and 56Ni with a half-life of 6.077 days. All of the remaining radioactive isotopes have half-lives that are less than 60 hours and the majority of these have half-lives that are less than 30 seconds. This element also has 8 meta states.
The article is really funny, because they talk about how this company's innovation could be used in pacemakers. When they had betavoltaic pacemakers in the 1970s. https://en.wikipedia.org/wiki/Betavoltaic_device
You’ve touched on a great point. The power provided is so low that solar can effectively provide equivalent power in nearly every application except one where the continuous operating environment is pitch black. 15x15mm for 0.0001w is small. For comparison, that’s about 1/6 of the power that falls on a 15x15mm patch in an indoor office (300lux environment with led lighting), out about the same as could be harvested by an efficient solar panel off the same size. You could collect a full days power from this battery (and store it in a 2mm thick li cell behind the panel) in roughly three minutes of sunshine or ten to fifteen minutes on an overcast day.
There certainly are applications where it would be useful, but most could just as easily be served by a small solar patch and lithium cell or super capacitor.
Here's the summary for the wikipedia article you mentioned in your comment:
A betavoltaic device (betavoltaic cell or betavoltaic battery) is a type of nuclear battery which generates electric current from beta particles (electrons) emitted from a radioactive source, using semiconductor junctions. A common source used is the hydrogen isotope tritium. Unlike most nuclear power sources which use nuclear radiation to generate heat which then is used to generate electricity, betavoltaic devices use a non-thermal conversion process, converting the electron-hole pairs produced by the ionization trail of beta particles traversing a semiconductor.Betavoltaic power sources (and the related technology of alphavoltaic power sources) are particularly well-suited to low-power electrical applications where long life of the energy source is needed, such as implantable medical devices or military and space applications.
Once they have a one watt version, this would be good for trickle charging when you are not using the device, such as when you're sleeping. But you would definitely need a lithium battery alongside it for normal use.
Yes I’m talking about recharging a battery sitting next to this; agreed that it can’t power a node directly. In the U.K. we are actually allowed to transmit up to 500 mW on the ISM band (provided we adhere to the utilisation quota, which I think is 15%)