The Battery That's Lasted 176 Years.  - Page 1
Forum section: electronics / general

author: firewalker
author_rank: Super Contributor
timestamp: August 22, 2016, 04:55:07 pm
content: Did know that!Alexander.

author: edy
author_rank: Super Contributor
timestamp: August 22, 2016, 06:15:01 pm
content: Awesome! Looks like a great project to try and build, knowing it will keep ringing long after you're dead. Pretty cool to see what is seemingly a simple machine work so elegantly for so long!

author: SeanB
author_rank: Super Contributor
timestamp: August 22, 2016, 06:23:53 pm
content: There they are saying they cannot look inside the battery pile to see the construction. Perhaps Mike or Fraser could offer them a free Xray or two, if they are unable to find the research lab on campus, which very likely has a few portable metallurgical Xray units, or even the dental school or the animal research units.

author: N2IXK
author_rank: Frequent Contributor
timestamp: August 22, 2016, 07:12:21 pm
content: https://en.wikipedia.org/wiki/Zamboni_pile

author: Red Squirrel
author_rank: Super Contributor
timestamp: August 22, 2016, 11:28:59 pm
content: That's pretty awesome. Would definity be interesting to see how the structure changes over time. I imagine the actual molecular structure of the metals change, like it starts to oxidize or something?

author: Macbeth
author_rank: Super Contributor
timestamp: August 22, 2016, 11:43:08 pm
content: Liars. The OEM stated it would only work for 4-5 years. If it is working beyond those parametersover 170 years later then it is out of calibrationThey keep it in a sound proof cabinet so you can't hear it ringing the bells. If it really is producing a considerable voltage then there is no need to destroy it, a very high impedance divider to the input of a typical high impedance 6.5+ digit DMM would be enough.

author: timb
author_rank: Super Contributor
timestamp: August 23, 2016, 03:03:22 am
content: Quote from: Macbeth on August 22, 2016, 11:43:08 pmThe voltage out of the battery is around 2kV (yes, two thousand volts), but it's only capable of putting out a few nA of current. So what you *really* need is an electrometer (with tens or hundreds gigaohm impedance).A typical 10Mohm DMM would have way too much leakage current and wouldn't be useable.

author: Artlav
author_rank: Frequent Contributor
timestamp: August 23, 2016, 10:18:02 pm
content: Hm, at 1nA and 2Kv that thing only spent 3 Wh of energy over these years, about the capacity of an AA cell.Doesn't sound too much considering the size of the batteries.The lack of self-discharge is the impressive part, i would say.

author: dannyf
author_rank: Super Contributor
timestamp: August 23, 2016, 10:31:10 pm
content: Nuclear fuel cells can have very long life.Still, 176 years are impressive even for today, let alone 1800s.

author: DimitriP
author_rank: Super Contributor
timestamp: August 23, 2016, 11:23:01 pm
content: QuoteX-rays might harm the energizer bunny or take away the mystery or both.

author: Ian.M
author_rank: Super Contributor
timestamp: August 24, 2016, 12:19:47 am
content: The Oxford Electric bell is a recurring topic here, e.ghttps://www.eevblog.com/forum/chat/oxford-electric-bell-ringing-since-1840/, but its nice to see a new colour video of it.The dry pile batteries in the bell have lasted approximately forty times longer than the manufacturers expected. They are coated in sulphur to seal them and retain the moisture in the electrolyte saturating whatever porous separator was used.Sulphur is amorphous when first solidified, but after 176 years, it must have fully reverted to its brittle crystalline form. *ANY* movement risks micro-cracking the sulphur seal, and nobody knows whether the electrolyte is sufficiently hygroscopic not to dry out if the seal cracks slightly. It would be nice to get an X-ray of the piles, but not at the risk of the batteries dying before they reach 180 years.I think the Clarendon Laboratory should stick a contact mike to the bell's dome, and add an amplifier and a 'press to hear the bell' button to the display case, and also put it on a webcam.

author: bitslice
author_rank: Frequent Contributor
timestamp: August 25, 2016, 10:30:52 am
content: Quote from: timb on August 23, 2016, 03:03:22 amI was wondering if we had anything better developed by now, and I found this non contact method.http://resource.npl.co.uk/docs/networks/electromagnetics/071129/dclf_wright/prance.pdf

author: bookaboo
author_rank: Frequent Contributor
timestamp: August 25, 2016, 10:37:37 am
content: Cant believe we havent had a batteriser joke yet.

author: timb
author_rank: Super Contributor
timestamp: August 25, 2016, 11:05:30 pm
content: Quote from: bitslice on August 25, 2016, 10:30:52 amI think that will only work for an AC source...

author: ez24
author_rank: Super Contributor
timestamp: August 25, 2016, 11:40:39 pm
content: Quote from: Ian.M on August 24, 2016, 12:19:47 amThis is so obvious I wonder what is the reason they do not. Maybe no sound? Seems if it was actually making sound, more energy would have been used. So my guess is that after three years the hammer does not touch the bells. I think this is a physics trick

author: bitslice
author_rank: Frequent Contributor
timestamp: August 27, 2016, 10:26:39 am
content: Quote from: timb on August 25, 2016, 11:05:30 pmIt quotes a bandwidth down to DC, so I took that to mean it would detect a pulse of current?

author: Kilrah
author_rank: Unknown
timestamp: August 27, 2016, 12:46:06 pm
content: Quote from: Macbeth on August 22, 2016, 11:43:08 pmI think we still have a long way to go about predicting battery longevity under super low currents

author: Macbeth
author_rank: Super Contributor
timestamp: August 28, 2016, 07:12:10 pm
content: Quote from: Kilrah on August 27, 2016, 12:46:06 pmBlimey, going by that data your lab must be pretty cold. About -56°C by my estimation

author: Kilrah
author_rank: Unknown
timestamp: August 28, 2016, 07:20:51 pm
content: I wish... cooking at 30°+ these days

author: Delta
author_rank: Super Contributor
timestamp: August 28, 2016, 10:06:40 pm
content: Just think of the possibilities, if only there was a device which could extend battery life by a factor of 8...That thing could last over 1400 years!

author: Flappy
author_rank: Contributor
timestamp: December 28, 2016, 02:39:13 am
content: Quote from: bookaboo on August 25, 2016, 10:37:37 am

author: tggzzz
author_rank: Super Contributor
timestamp: December 28, 2016, 09:09:29 am
content: Quote from: Kilrah on August 27, 2016, 12:46:06 pmThat's more to do with predicting the leakage in the RAM - which is highly variable to start with and then it is highly sensitive to temperature. HP engineers will have made appropriately pessimistic assumptions.

author: tggzzz
author_rank: Super Contributor
timestamp: December 28, 2016, 09:19:16 am
content: I've just rescued a 68 year old standard Weston cell from a trip to the tip. They are supposed to have a lifetime of a only few decades, but this is apparently still accurate at 1.01865V. Mind you, I've only got an HP 5.5 digit DMM, and I haven't accounted for the changesin the definition of the Volt since the cell was manufactured.Pretty pictures athttps://www.eevblog.com/forum/metrology/1000-my-%28hi%29story-of-the-weston-cell-of-the-volt-and-of-being-a-volt-nuts/msg1100033/#msg1100033

author: Gyro
author_rank: Super Contributor
timestamp: December 28, 2016, 10:10:05 am
content: QuoteAs far as I can tell, unlike Unsaturated cells, the life of a Saturated cell that you have is determined by the charge it delivers. In the case of my Muirhead K-375-C it is 1 Coulomb = 1A/s. Being hermetic, the limiting elements are probably external insulation, internal leakage current (?) and current drawn during measurement.Keep it spotlessly clean and dry and go for the record!Of course the one at Oxford has actually been ringing a bell for all these years!

author: tggzzz
author_rank: Super Contributor
timestamp: December 28, 2016, 10:51:28 am
content: Quote from: Gyro on December 28, 2016, 10:10:05 amI'm not quite sure of that's the case, unfortunately. However, in this respect at least, the Dunning-Kruger force is weak in me: I'm not sure how much of any "inaccuracy" is due to "excessive" voltnutteryAll I know about Weston cells was gained during school physics practicals and during the last week fromhttps://www.eevblog.com/forum/metrology/muirhead-std-and-ref-cells-all-catalogue-info-uploaded-!-%28ayce%29/ You know about the latter, of course.