> NDB says [the batteries] will be cost-competitive with, and sometimes significantly less expensive than – current lithium batteries. That equation is helped along by the fact that some of the suppliers of the original nuclear waste will pay NDB to take it off their hands.
Yikes, I had caught the shattering risk and decided I'd pass on something built literally like the article said. But if these can burn... that takes it to "that externality needs to be fully mitigated before this is made widely available".
This is silly. It's not going to disrupt Li-ion. Power outputs are way too low. C14 has a half life of 5700 years. This isn't going to output Li-ion levels of power/weight for 5 millennia. It looks like it might give you microwatts/gram, but this is much closer to existing nuclear tech like RTGs or beta voltaics than it is to Li-ion batteries.
The half life tells you how fast you're using up your fuel. A long half life means you're using the nuclear potential energy in your "battery" very slowly.
Yeah, the way they're presenting it is silly.
C-14 decays to N-14 with a mass defect of 156.5 keV/c^2. With a half life of 5730 years, 1 kg of carbon-14 will produce 1.6×10¹⁴ decay events per second. That's 3.8 W/kg specific power, which is roughly 1% of lithium ion -- assuming 100% conversion efficiency.
HOWEVER, we know that only 31% of the decay energy is actually carried away by the beta particles, and the rest ends up as heat (which is not captured)[1]. On top of that, the efficiency of converting the beta particle's kinetic energy into electrical power is low. I found a paper citing a 26% conversion efficiency [2], which seems high but lets go with it. Finally, the mass of the battery obviously includes more than just the C-14. Lets assume that half the mass of the battery is C-14.
That would bring us down to 300 microwatts per gram of C-14, and less than 0.05% of the specific power of a LiIon battery.
[1] There's also a positron that shares half of this energy -- I don't know if these devices capture that, so I'm just leaving it in.
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[ 2.8 ms ] story [ 60.7 ms ] threadEdit: apparently these devices are called betavoltaics
Betting these will end up in pacemakers & telemetry only, but not for any legitimate reason.
How much C-14 is produce annually?
Yikes, I had caught the shattering risk and decided I'd pass on something built literally like the article said. But if these can burn... that takes it to "that externality needs to be fully mitigated before this is made widely available".
My first thought was "Chief Medical Officer? Huh? No. Thanks. I smell bs."
https://www.snopes.com/fact-check/radioactive-diamond-batter...
But this is continuous process. So in 24hrs, you would get 12kwh which can be stored in super capacitors.
Assuming 10kms per kwh of EV range, this would be 120kms per day.
And if we allocate more kgs for battery, the range would increase.
HOWEVER, we know that only 31% of the decay energy is actually carried away by the beta particles, and the rest ends up as heat (which is not captured)[1]. On top of that, the efficiency of converting the beta particle's kinetic energy into electrical power is low. I found a paper citing a 26% conversion efficiency [2], which seems high but lets go with it. Finally, the mass of the battery obviously includes more than just the C-14. Lets assume that half the mass of the battery is C-14.
That would bring us down to 300 microwatts per gram of C-14, and less than 0.05% of the specific power of a LiIon battery.
[1] There's also a positron that shares half of this energy -- I don't know if these devices capture that, so I'm just leaving it in.
[2] https://www.sciencedirect.com/science/article/pii/S016890022...)
Also, the description of the technology sounds so simple that I find it difficult to believe no-one's thought of it before ergo there must be a catch.
It would be great if this was for real though. The possibilities of such such a thing are almost unimaginable.