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Russian Scientists Upgrade Nuclear Battery Design To Increase Power Output (sciencealert.com)
schwit1 shares a report from ScienceAlert: A team of Russian researchers have put a new spin on technology that uses the beta decay of a radioactive element to create differences in voltage. The devices are made of stacks of isotope of nickel-63 sandwiched between a pair of special semiconducting diodes called a Schottky barrier. This barrier keeps a current headed one way, a feature often used to turn alternating currents into direct ones. Finding that the optimal thickness of each layer was just 2 micrometers, the researchers were able to maximize the voltage produced by every gram of isotope.
Nickel-63 has a half-life of just over 100 years, which in an optimized system like this adds up to 3,300 milliwatt-hours of energy per gram: ten times the specific energy of your typical electrochemical cell. It's a significant step up from previous nickel-63 betavoltaic devices, and while it isn't quite enough to power your smart phone, it does bring it into a realm of being useful for a wide variety of tasks.
Nickel-63 has a half-life of just over 100 years, which in an optimized system like this adds up to 3,300 milliwatt-hours of energy per gram: ten times the specific energy of your typical electrochemical cell. It's a significant step up from previous nickel-63 betavoltaic devices, and while it isn't quite enough to power your smart phone, it does bring it into a realm of being useful for a wide variety of tasks.
Buying a 100-year-old Tesla and having to replace the original battery.
I'd rather have a nuclear battery in a pacemaker that lasts a lifetime than having to deal with surgery every 10 years to replace a conventional one, risking infection and other complications.
Isn't beta-decay a process that produces exponentially less energy over time? Like, after 100 years, it'll still produce half the voltage (or amperage) out. After 200, 25%. But after 25 years it'll only produce 70.7% of the output, which may not be enough. Or it could be more than enough at 200 years.
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Nickel-63 is an artificial isotope, which means it has to be made; But, it only decays by beta decay, so a piece of foil (or a deposited schottky barrier) will prevent that from escaping.
Pu RTG's put out everything from alphas to heavy fission gammas and neutrons, so this is a gogolplex better from any radioactivity standpoint.
I hope this takes off; it all depends on what it costs to make a gram. A 3300mAh lithium battery is about $1 in quantity, but has a very limited lifetime.
Truth isn't Truth - Guliani
Is "3,300 milliwatt-hours" the same as 3.3 Watt-hours?
Or should we really be measuring this in Libraries of Congress?
No sig today...
But after 25 years it'll only produce 70.7% of the output
The fraction of remaining power = exp(-t * ln(2)/100)
So after 25 years, it will be a 84%. It will be at 70.7% after 50 years. If that isn't enough, then just make the battery 40% bigger.
If you read the https://www.sciencedirect.com/science/article/pii/S0925963517307495 you find that the actual power density is 10uW/cm^3, which is really very very poor compared to batteries. Yes, it will run for many years without charging, but it won't run a very big load.
that is 3.3 watt/hours per gram. According to my calculations, you can use a 80 kg battery can easily power a Tesla for the next 100 years. A Model S can do 320kw/hour. No supercharger needed. Another option is to use a 16Kg battery which will charge the battery packs. Only in extreme use, long trips, etc. you may need an outside charge.
But this isn't like a Li-Ion battery that you can extract energy from at a variable rate... it's a generator that produces ~38uW (micro-watts) continuously for 100 years. So you just need ~66kg to produce a standard 0.5 amp USB charger worth of current at 5V. But on the up side... that 66kg "battery" will charge your phone for 100 years. ... and if you want to red line that tesla for 100 years straight you just need an... 8,430 metric ton battery - no problem, just buy a Model X with a tow hitch!
http://citeseerx.ist.psu.edu/v...
These look like good things for deep space missions, but where else would you find a good use for them, that solar couldn't do more effectively?
Model S can do about 300 Wh per mile. A 80 kg battery, at 3.3 Wh/gram, can deliver 264 kWh, so about 880 miles total. But the problem is that this battery can only deliver this power gradually over 100+ years, so you would have to drive very slowly.
Yeah I noticed that they were measuring the output in microAmps. I don't have anything that can run on something like 60 uA. Load capacity is always the problem with betavoltaics. I wonder how hard it would be to put a million of these in parallel though. That could make for a very interesting battery depending on the size and weight involved.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
Half life is 100 years.
So, half, that is 5 times the chemical batteries is available over 100 years. Right?
So, on average, 1/20 of the energy is available per year .
That works out to 1/7300 per day. But the decay is exponential, so we need a correction from mean to peak. Let us be generous and round up e (=2.7182818) to 3. So you are looking at 1/2500 of chemical battery energy per day. Divide by another 86400 to get per second. That is the max power out put of this device. Looks like you would be better off harvesting the power from local WiFi signals.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
How does the inevitable high levels of environmental radiation play out in your imaginary world? Because cars, cargo boat and plane crashes all occur on a regular basis, and in a fission powered world those crashes would often mean nasty highly radioactive waste products getting spread around.
The problem is not the fear of radioactive contamination - the danger is real. The problem is that we don't have any technology safe enough to reduce that danger to something tolerable outside a well-regulated power plant (and fear well may have contributed to that). You can't even trust people to dispose of batteries and household chemicals properly when doing so is free and easy, and big companies like BP routinely get away with a slap on the wrist when causing massive damage via negligence and then intentionally worsening the problem in order to make it less visible - messes which rarely ever get adequately cleaned up. Hell, whole cities like Flint have had toxic water supplies for years that the residents can't even decline to pay for if they want to keep their kids. And do you really want to live in a world where any car bomb gets the radioactive dirty bomb part for free?
Fusion may eventually change that - generally speaking there's no direct waste products, and neutron activation problems can be mitigated with lithium shielding. And then by all means let's play. Even something like a compact Lockheed Martin fusion reactor wouldn't be something I'd want in a car though - break the reactor and reaction-based radioactivity ends almost immediately. Those inner coils though will inevitably be neutron activated though, and I wouldn't want to be the one responsible for cleaning up the mess. No fast and cheap tow-truck services to clear an intersection after a bad mash-up.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
That is 3.3Wh per g, _distributed_ over some centuries...
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.