Betavoltaics

[Todg]

So called 'nuclear' batteries, seem to have a lot of potential for replacing conventional batteries. This came up in anothert thread, but I've moved it here. Will dead batteries at the critical moment be a thing of the past at higher tech levels? What are the concerns/dangers and how serious are they. I like the idea that the battery in my electronic sight is good for 10 years. But is it realistic?

Here's an introduction to betavoltaics:

http://peswiki.com/energy/PowerPedia:Beta_voltaic

 

[Anthony]

Hm. I find it disturbing that this article makes claims about stimulated beta emission; I'm not aware of any credible research showing that stimulated beta decay is possible (obviously, it is possible in Traveller; nuclear dampers clearly stimulate or suppress decay). I also would debate the 'cheap' claim.

 

[Todg]

Agree, but this is in the context of Traveller.

If one assumes the technology is achievable in the Traveller 'verse, then it makes for an interesting alternative to power sources listed. Batteries play a big part in CT as a power source. These are usually described as 'can be recharged at any ships power plant', etc. The alternatives is typically a fusion plant or some other high tech power source.

In particular, look at robots as described in CT. You've got fuel cells or fusion for anything useable. With a viable betavoltaic in your TU, you now have the possibility of having a robotic manservant that doesn't need refueling every night.

Or an ATV that's good for 10 years,

Etc, etc.

So if we work from the given potential of 10^7 watt-hours per kilo of isotope, what can we come up with for size and weight of various betavoltaic batteries for use in Traveller?

 

[Todg]

As an addenda, i found this interesting"

However, betavoltaics can be used in conjunction with standard battery technology to create a hybrid power source with the best features of both. The betavoltaic power cell, although not powerful enough to directly power the device, would provide a constant trickle charge to the battery, recharging it between uses. The battery would then provide the high-wattage output to power the device. Unlike today's rechargeable batteries, this hybrid cell would recharge itself over time without needing to be plugged into a wall outlet, drawing power from the enormous, but slowly released, reserves of the nuclear battery. With a half-life of 12.3 years, a tritium battery could serve a portable electronic device for its entire useful life without ever needing to be replaced

To go back to out Betavoltaic powered robot, maybe the thing actually runs on batteries, trickle charged from a betavoltaic. Old Jeeves runs down, but it's nothing a good few hours of 'sleep' won't put right.

This same technology will be ideal for any electronic device that is used intermittantly - flashlights that recharge themselves during the day, cell phones that don't need a charger, etc.

 

[Anthony]

Damper-modulated radioisotope batteries make a good replacement for Fusion+ -- they're basically power plants, not batteries in the conventional sense. I'd just use the Fusion+ stats (in GURPS, treat as an NPU or RTG).

 

[parmasson]

Get hit by a nuclear damper field/ray and all of your small electronics go out.

 

[Fritz_Brown]

Exactly, Parmasson. Also, what about heat? This thing would have to produce the same amount of energy as the battery (to recharge it), and batteries with any real power get hot. Of course, we have fusion reactors in backpacks, so....

Anthony, how big is a nuclear damper? IIRC, its as big as a fusion backpack, so there's no real advantage to a damper controlled beta battery.

 

[Todg]

Actually, the betavoltaic doen't have to be as big as the battery. Ifg you are using it as a trickle charger, it can be well above the max output of the battery. But it requires a device that only operated on full power occasionally.

Think in terms of a cell phone. A cell phone only draws a large amount of power transmitting. Most of the time it's just riding around waiting for a call. This is why you can get days of power from a 4 volt, 1000mAH battery. The Betavoltaic just replaced the regular charger with a low power, 'always on trickle charger'. (BTW, this is a proposed RL use for a betavoltaic)

There will be heat but spread out over the full charging cycle.

 

[Anthony]

Originally posted by Fritz88:

Anthony, how big is a nuclear damper?

Minimum size isn't specified anywhere that I know of, though I may have missed a reference. In any case, I agree it's probably too big for compact devices. However, fusion+ also had a minimum size.

 

[parmasson]

According to one site an RTG has an energy conversion of 8%. How would this increase with TL? The reason I ask is these would make great last ditch power sources for life support systems aboard starships. I guess the Soviet ones TL-6/7 can handle 80 watts. How about at TL-12?

 

[Anthony]

For an RTG with no moving parts, efficiency is never going to be very high, because there isn't a big temperature difference between the hot and cold end.

It's likely that ships contain long endurance low power high reliability power sources of some type, possibly RTGs. They're pretty much below the resolution of the design system, however.

 

[archhealer]

All physics aside, I love the idea of robots who have to 'sleep'. It especially makes robot PCs a lot more viable.

 

[archhealer]

I just love the idea of robots that sleep. Makes robotic PCs a lot more viable. It also leaves a lot more options for abandoned systems haveing monitors and SDBs just drifting about 'dormant' till a sensor reading trips a switch and they come back to life....

 

[parmasson]

The reason I ask is that power plants seem to use Black Box Technology ™ to generate electricity. I had kinda figured that by TL-12 a “power converter” would capture the particles and convert them into electricity.