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Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
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11th Jun 2016, 11:56 am | #61 |
Octode
Join Date: May 2011
Location: Lancashire, UK.
Posts: 1,351
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Re: Amazing D cell discovery!
Instinct might say yes, experience with Duracell and Energizer says no. They just leak (in my experience)
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11th Jun 2016, 12:46 pm | #62 |
Moderator
Join Date: Jun 2003
Location: Oxford, UK
Posts: 27,966
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Re: Amazing D cell discovery!
Yes, conventional wisdom used to be that they were much more likely to leak if discharged, but that no longer seems to be the case. It's just down to a mixture of luck and age now.
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11th Jun 2016, 12:51 pm | #63 |
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Re: Amazing D cell discovery!
It was the case with the old zinc/carbon cells using the zinc as the casing, the act of discharging them ate away at the zinc.
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12th Jun 2016, 2:51 pm | #64 |
Heptode
Join Date: Dec 2014
Location: Limerick, Ireland.
Posts: 901
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Re: Amazing D cell discovery!
Alkaline batteries can have 10 years "shelf" life in cooler conditions. It's Zinc Carbon, Zinc Chloride that have very poor life.
Layer cells are close to Alkaline capacity, but only at low currents due to higher resistance. They don't last as well, but are better than Zinc Carbon. That's why after the 1940s the only HT pack still used for new valve portables was the Portable61. Everything else after AD3 was Layer cells for HT, but as the filament was 25mA to 300mA depending on model that part was D cells or F cells for parallel filaments and B cells only for smaller series filament packs (B = cells in a 1289 torch battery or HT cells in all non-layer HT, or Grid Bias). The PP3, PP6, PP7, PP9 etc are all based exactly (W x H x D) on layer cells for photo batteries or HT packs. Only poorly made Alkaline leak. Having - at top is best, it's the base seal that leaks. The case is positive. Some have a too thin plastic film that needs extra insulation to avoid shorting to metal holders with sharp edges. |
12th Jun 2016, 4:27 pm | #65 |
Heptode
Join Date: May 2015
Location: Bradford, West Yorkshire, UK.
Posts: 512
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Re: Amazing D cell discovery!
A while ago I was >harvesting< the zinc from exhausted cells picked out of the supermarket "recycle". I wanted the zinc to use as kathode/anode electroplate a couple of engine mounts.
I pulled out a few of the big 6 volt lantern cells (good zinc sources) and also found some "D" sized zinc chloride cells. The "D" cells did NOT have a zinc outer, after stripping them down I found they had a thin zinc coating on the inside of the steel outer case, I figured that when the battery was getting low on zinc, the chemicals inside would just eat through the thin steel casing in no time. I found that PP3 batteries come in 2 flavours, one type contains pile cells and the other type has 6 "AAAA" cells inside.
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worried about the electrons entering the circuit and the smoke leaving Andrew |
13th Jun 2016, 5:10 am | #66 | |
Retired Dormant Member
Join Date: Feb 2008
Location: Auckland, New Zealand
Posts: 631
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Re: Amazing D cell discovery!
Quote:
That is a development that I hadn't seen in Auckland. How strange that they would have had different packaging and colours for the same basic product! Perhaps they were aware of the 'DSE cells' weaknesses and wanted to get a handle on complaints and returns. The black and gold are just pitiful! Cheers Billy |
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13th Jun 2016, 1:37 pm | #67 | |
Heptode
Join Date: Dec 2014
Location: Limerick, Ireland.
Posts: 901
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Re: Amazing D cell discovery!
Quote:
The layer cell type (1) at low current is better value, if shelf life isn't important as the cells fit case better than the common type (3) Alkaline. Much less difference in capacity than AA Zinc Carbon and Alkaline (which is about x2, the x5 life is special case). The Rechargeable are again stacked "button cell" (NiCd and some NiMH) or NiMH similar to AAAA, but a little shorter. The stacked type come in 6 cell (better capacity) or 7 cell (better voltage), i.e. 7.2V or 8.4V nominal for NiCd and 7.5V or 8.75 nominal for NiMH. Capacity is terrible at low current draw compared to regular layer cell or Alkaline. Use only Alkaline in Smoke detectors, intermittently used test gear etc. Only use Rechargeable for motorised or things charged before use due to low capacity and high self discharge. Unlike cylindrical based Zinc Carbon/Zinc Chloride vs Alkaline the Layer type are far better value for regularly used low current drain such as a transistor set or 45V to 90V miniature valve HT pack used regularly. |
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13th Jun 2016, 2:10 pm | #68 |
Nonode
Join Date: Mar 2010
Location: Dukinfield, Cheshire, UK.
Posts: 2,038
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Re: Amazing D cell discovery!
It's amazing how some batteries can last so long. I originally posted this a couple of years ago:
Our front doorbell recently stopped working, and on investigation I found that one of the four C cells was open circuit. The remaining three all read slightly under 1.5v. These batteries had never been changed since the doorbell was first fitted in 1996! And not a sign of corrosion or leakage. At the other end of the scale, my digital micrometer seems to drain the tiny mercury battery stone dead even when not in use....
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Andy G1HBE. |
13th Jun 2016, 3:17 pm | #69 |
Nonode
Join Date: Oct 2014
Location: West Midlands, UK.
Posts: 2,181
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Re: Amazing D cell discovery!
Possibly slightly O/T, but I've always found Asda Alkaline fairly good value for money.
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13th Jun 2016, 3:28 pm | #70 |
Octode
Join Date: May 2010
Location: Worcestershire, UK.
Posts: 1,880
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Re: Amazing D cell discovery!
That happens with my digital vernier too, I now remove the battery when not in use, which is a pain!
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13th Jun 2016, 4:30 pm | #71 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,861
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Re: Amazing D cell discovery!
I have to say that I've taken to doing that with all my occasional-used gadgets now. The way all brands of batteries seem to spontaneously leak these days, it's the only way to avoid extensive damage.
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13th Jun 2016, 5:31 pm | #72 |
Dekatron
Join Date: Jun 2015
Location: Biggin Hill, London, UK.
Posts: 5,215
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Re: Amazing D cell discovery!
I find it a bit ironic that while we are told to 'save energy' these days, a lot of (battery powered especially) devices do not have a real on/off switch, only a 'soft' one that puts the thing into standby mode and leaves a fair amount of circuitry powered up. Yes, it's low power, but it still draws some current.
On quite a few of my devices that I use reasonably frequently (and therefore don't want to keep taking the batteries out) and which don't store important data when powered down I have fitted a physical on/off switch. This has saved me a lot of battery replacements over the years. |
14th Jun 2016, 11:53 am | #73 |
Heptode
Join Date: Dec 2014
Location: Limerick, Ireland.
Posts: 901
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Re: Amazing D cell discovery!
Some devices only mute interface, turn off modulator or pretend to be off.
I like real power switches |
17th Aug 2016, 10:30 am | #74 |
Nonode
Join Date: Aug 2015
Location: Cambridge, Cambs. UK.
Posts: 2,198
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Re: Amazing D cell discovery!
Just had a pleasant surprise removing these three Duracell D cells from a 'barn find' Bruel & Kjaer sound level meter. When I saw that there were batteries still present in the instrument, I mentally wrote off the battery chamber, expecting it to be corroded to oblivion. However, these three cells, with September 1995 expiry dates are completely leak-free. They're probably at least 25 years old! Comparison with today's corrosion problems suggests that 'they don't make 'em like they used to .
One cell even still registers 1V on open circuit and will still deliver 1A! The other two measure -32mV and -75mV. Maybe one of our chemists can explain why a thoroughly discharged battery often reverses polarity Incidentally, the SLM itself, also pictured, which I'd bought only for spares, just needed the mechanical meter movement replacing and it now works and, after cleaning, calibrates perfectly, so is a nice addition to my collection. Martin
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26th Aug 2019, 8:02 pm | #75 |
Pentode
Join Date: May 2010
Location: Sandviken, Sweden
Posts: 233
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Old Panasonic cells
I came upon a Simpson 260 meter at work that was going to be scrapped, I took it home instead. It seems to work allright, even on the resistance ranges despite gathering dust for years. I opened it to take a look and found some pristine looking Panasonic 'ultra heavy duty' cells with use-before date of October 1991!
They all measure 1,55 volts on an Avo 8, the D cell is a bit tired and only manage 300ma when short circuited but the AA cells still gives 1,5 ampere and had no problem in powering a Mini Maglite. Quite impressive for cells that expired 28 years ago |
27th Aug 2019, 6:06 pm | #76 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,203
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Re: Amazing D cell discovery!
Especially given that they're zinc carbon. Are they 'Made in Belgium'?
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30th Aug 2019, 12:54 pm | #77 |
Octode
Join Date: Jan 2012
Location: Wimbledon, London, UK.
Posts: 1,465
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Re: Amazing D cell discovery!
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30th Aug 2019, 1:08 pm | #78 | |
Octode
Join Date: Jan 2012
Location: Wimbledon, London, UK.
Posts: 1,465
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Re: Amazing D cell discovery!
Quote:
Colin. |
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30th Aug 2019, 2:35 pm | #79 | |
Moderator
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Location: Oxford, UK
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Re: Amazing D cell discovery!
Quote:
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30th Aug 2019, 3:26 pm | #80 |
Octode
Join Date: May 2011
Location: Lancashire, UK.
Posts: 1,351
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Re: Amazing D cell discovery!
I've kept a simple log of AA batteries fitted to a Hewlett Packard Z4000 mouse and the results are interesting. The Lithium cells I fitted did not last anywhere near as long as you might expect. As a further experiment I have just this week fitted non alkalines (I'm assuming that these Kodaks are Zinc Chlorides. They are the '10+1 free' for a pound from Poundland).
I wonder how long they will last? Z4000 mouse, first use, 16/05/16 Energizer batteries fitted. Low battery warning light on 18th November and failure on 20th November 2016. 6 month run time. 20/11/16 Energizer Lithium cells fitted. Low battery warning light and failure on 25th Aug 2017. 9 month run time. 25/08/17 Kodak Alkaline batteries fitted. Low battery warning light on 28th Feb 2018 and failure on 3rd March 2018. 6 month run time. 03/03/18 Kodak Alkaline batteries fitted. Low battery warning light on 08th Aug 2018. 5 month run time. 08/08/18 Kodak Alkaline batteries fitted. Low battery warning appeared intermittently around 20/12/18. 25/12/18 Above fitted batteries recharged for 6 hours and re-fitted. (warning... don't try this at home) 01/03/19 Kodak Alkaline Batteries fitted. Low battery warning appeared around 25/08/19. 6 month run time. 28/08/19 Kodak Zinc Chloride batteries fitted. Where I have used Lithium (Energizers) successfully is in a large LCD clock and the main reason for trying them was to see if their more constant voltage maintained the high contrast display. I have to say yes, it did. In fact the open circuit voltage was higher than I liked and so I added a germanium diode in the supply. The two AA lithiums in this clock ran from mid May 2014 to mid August 2019 with the voltage remaining above 1.56 volts for most of that time. Failure was fairly sudden with the voltage dropping to 1.35V. The open circuit voltage was within a few millivolts of each other. A small LCD 'weather station' type clock saw similar lithiums last 3 years. Normally I would be replacing alkalines every 8 or 9 months or so, mainly to keep the display contrast up to scratch. |