“Imagine only replacing the batteries in a device once a decade, or even once a century. Nuclear batteries could one day let us do just that, but their power density is currently too low to be very practical. Now, Russian researchers have developed a new nuclear battery design based on nickel-63, which has a higher specific energy than regular, commercially-available batteries.

Nuclear power gets a bad rap, thanks to the fact that any nuclear material that escapes confinement can linger dangerously in the environment for decades or even centuries. But by the same token, if properly contained this longevity can be harnessed for good, releasing energy slowly and consistently over years.”

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Given nickel-63’s hundred-year half-life, the nuclear battery boasts about 3,300 milliWatt-hours of power per gram, which the team says is 10 times more than conventional electrochemical batteries.

Would it kill them to put that in standard specific energy, 11.9 MJ/kg. Makes comparison a tad easier. A Lithium Metal battery has around 1.8 MJ/kg, Lead acid battery 0.2 MJ/kg.

As it achieved a power output of around power output of about 1 μW I don’t think Tesla has much to worry about just yet :)

Spiny Norman said:

“Imagine only replacing the batteries in a device once a decade, or even once a century. Nuclear batteries could one day let us do just that, but their power density is currently too low to be very practical. Now, Russian researchers have developed a new nuclear battery design based on nickel-63, which has a higher specific energy than regular, commercially-available batteries.

Nuclear power gets a bad rap, thanks to the fact that any nuclear material that escapes confinement can linger dangerously in the environment for decades or even centuries. But by the same token, if properly contained this longevity can be harnessed for good, releasing energy slowly and consistently over years.”

More

There’s an interesting review from 2014 of the start of the art of nuclear batteries up until then. Copy this url into sci-hub to read it. https://www.sciencedirect.com/science/article/pii/S0149197014000961

Nuclear batteries have attracted the interest of researchers
since the early 1900s. There are many competing types of nuclear batteries: thermoelectric, thermophotoelectric, direct charge collection,
thermionic, scintillation intermediate, and direct energy conver-
sion alphavoltaics and betavoltaics. For the past forty years the
dominant nuclear battery technology has been the radioisotope
thermoelectric generator, or RTG.

Figure 1 is a flow chart explaining all the different options for nuclear batteries.

Fig. 1. Energy conversion flow chart for radiation sources. Branch 1 uses radiation for heat production. Branch 2 uses the production of charged species in a solid to generate a current flow. Branch 3 uses the production of charged species in a solid to produce laser photons. Branch 4 uses the production of charged species in a solid to produce photons which are used to produce electricity from photovoltaic (PV) cells. Branch 5 uses the production of charged species in a gas to produce photons which then interaction with photovoltaic (PV) cells to produce electricity. Branch 6 uses the production of charged species in a gas to produce laser photons. Branch 7 uses the production of charged species in a gas or liquid to produce chemicals through radiolysis.

See article for more.

Nickel-63 is one of 40 or so possible isotopes for nuclear batteries mentioned in the earlier review article. It is mentioned as a beta emitter with a beta particle energy greater than tritium but less that sulfur-37, strontium-90 and yttrium-90.

The relatively small energy of the beta particles allow them to be stopped in a short distance, with a 50% stoppage by just 1 micron of silicon carbide, for instance. This allows the Russians in the article linked by the OP to use multiple layers is a very small space to get a high energy density.

Nickel-63 is synthetic, obviously. But is it produced as a fission product, by neutron capture in a reactor or in a synchrotron?

> The maximum electrical output power of about 0.93 μW was obtained in total volume of 5 × 5 × 3.5 mm^3.

0.93 microwatt is not a huge amount of electrical power.

mollwollfumble said:

> The maximum electrical output power of about 0.93 μW was obtained in total volume of 5 × 5 × 3.5 mm^3.

0.93 microwatt is not a huge amount of electrical power.

But it’s a fairly small volume too.

Seems it’s nearly one Watt per 100 cubic metres. Bargain…

Michael V said:

Seems it’s nearly one Watt per 100 cubic metres. Bargain…

I make it just over 10 W/m^3.