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Goes boom and expells murcury gas...read the article...[[User:Kr5t|Kr5t]] 22:48, 21 May 2006 (UTC)
:Alkaline cells have no added mercury; for all practical purposes, you can consider them to be essentially free from mercury. Please check your sources. chami 16:53, 28 October 2022 (UTC) <!-- Template:Unsigned --><small class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Ck.mitra|Ck.mitra]] ([[User talk:Ck.mitra#top|talk]] • [[Special:Contributions/Ck.mitra|contribs]]) </small> <!--Autosigned by SineBot-->
Where does it say anything about mercury gas? --[[User:Newton21989|Newton21989]] 01:55, 4 April 2007 (UTC)
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== White crystals ==
Sometimes alkaline batteries leak, a clear fluid. But sometimes white crystal powder forms at one end. It seems to corrode contacts. What exactly is this white material, what exactly causes it, how can it be avoided, and what contact materials are most resistant to corrosion? -[[User:69.87.193.60|69.87.193.60]] 17:27, 22 March 2007 (UTC)
:the liquid is KOH, chemically known as potassium hydroxide, an extremely corrosive liquid (solution). slowly it absorbs carbon dioxide from the air and forms potassium carbonate, similar to soda ash, with the chemical formula K<sub>2</sub>CO<sub>3</sub>. This is less corrosive but you should still handle it with care. chami 17:00, 28 October 2022 (UTC) <!-- Template:Unsigned --><small class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Ck.mitra|Ck.mitra]] ([[User talk:Ck.mitra#top|talk]] • [[Special:Contributions/Ck.mitra|contribs]]) </small> <!--Autosigned by SineBot-->
*I've had this happen many times while [[recharging alkaline batteries]]. This is [[potassium hydroxide]] and in my experience, has not seemed to cause any damage to myself or objects it comes in contact with. My advice, to be safe, is just wipe it up with a paper towel, or likewise and throw the battery (It's no good after it pops.) and the towel into a trash container.
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: ((Now, if only one of the rechargeable battery manufacturers would incorporate the same idea into THEIR products, it would make life SO much easier when having to put a set of NiMHs into some infrequently used device, out of a drawer with a couple dozen of them in... I mean, battery testers and multimeters exist, but they're all kinda fiddly...)) [[Special:Contributions/193.63.174.254|193.63.174.254]] ([[User talk:193.63.174.254|talk]]) 16:36, 21 February 2017 (UTC)
::Unfortunately, they would be useless on a NiMH battery. The internal resistance of primary batteries rises as the insoluble reaction products are produced. This imposes an increasing limit on the current that can be produced which the battery tester can measure. There are no such products in a NiMH battery and nothing to limit the current as it discharges. These batteries maintain a near constant voltage and internal resistance during their discharge cycle and then, more or less, die suddenly as the reactants are consumed. [[Special:Contributions/86.134.23.220|86.134.23.220]] ([[User talk:86.134.23.220|talk]]) 13:38, 23 March 2021 (UTC)
== Battery names ==
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*'''Strong Oppose''' and suggest speedy close (is that possible?). This is not what the general public would be looking for. [[User:HumphreyW|HumphreyW]] ([[User talk:HumphreyW|talk]]) 15:25, 9 October 2009 (UTC)
*'''Oppose''' [[WP:COMMONNAME]] [[Special:Contributions/76.66.197.30|76.66.197.30]] ([[User talk:76.66.197.30|talk]]) 16:12, 9 October 2009 (UTC)
*'''Oppose''' The term "battery" is almost always used by consumers, battery manufacturers, etc. '''<span style="border: 2px Maroon solid;background:#4682B4;font-family: Monotype Corsiva">[[User:TJ Spyke|<
===Move discussion in process===
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minimize mass-transport polarization of reactant and product).
On discharge, the manganese dioxide cathode undergoes at first a one-electron reduction
to the oxyhydroxide...</blockquote> (David Linden, Thomas B. Reddy (ed). ''Handbook Of Batteries 3rd Edition''. McGraw-Hill, New York, 2002 {{ISBN
because I sometimes don't have it handy when I need to revert the vandals. --[[User:Wtshymanski|Wtshymanski]] ([[User talk:Wtshymanski|talk]]) 22:49, 9 December 2009 (UTC)
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== leaking ==
Hi, when the pottasium hydroxide is leaking out it is not forming crystals. It is reacting with CO2 from air and forms Potassium carbonate (: 2KOH + CO<sub>2</sub>
I'm not so much advanced in english so i don't want to edit directly. <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/90.176.57.105|90.176.57.105]] ([[User talk:90.176.57.105|talk]]) 18:03, 21 March 2010 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->
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== External links modified ==
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Why don't I find an explanation in the text why alkaline batteries are called alkaline? I know that a pH>7 equals alkaline, however, which part is alkaline? And is there a more accurate number that tells how alkaline it is? Does the degree of alkalinity change over time of discharge? It probably is very basic information but it is lacking. --[[User:VanBuren|VanBuren]] ([[User talk:VanBuren|talk]]) 11:59, 27 March 2017 (UTC)
: Fourth line of the lead says "The alkaline battery gets its name because it has an alkaline electrolyte of potassium hydroxide, instead of the acidic ammonium chloride or zinc chloride electrolyte of the zinc-carbon batteries. " I've never seen anything where the pH of the electrolyte is correlated with the condition of the battery. Since it's a saturated solution and since the electrolyte isn't a reactant in these batteries (or not intended as the reactant, anyway), I wouldn't have thought to look for a correlation between pH and battery charge. --[[User:Wtshymanski|Wtshymanski]] ([[User talk:Wtshymanski|talk]]) 19:26, 27 March 2017 (UTC)
::Thanks, did not see that line with explanation. --[[User:VanBuren|VanBuren]] ([[User talk:VanBuren|talk]]) 07:01, 28 March 2017 (UTC)
::The alkaline battery gets its name because it has an alkaline electrolyte of potassium hydroxide- This is true.
::Since it's a saturated solution- false. A saturated solution of KOH will react with Zn and produce H<sub>2</sub> gas. Please check your source.
::since the electrolyte isn't a reactant- false. The chemical reaction you mentioned is correct and OH<sup>-</sup> ions are consumed (they are released at a different place) in the reaction. In fact the ZnO is never produced but we actually get potassium zincate (there is an article on sodium zincate in wikipedia). For every mole of Zinc metal, approx 2-4 moles of KOH are consumed. chami 17:28, 28 October 2022 (UTC) <!-- Template:Unsigned --><small class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Ck.mitra|Ck.mitra]] ([[User talk:Ck.mitra#top|talk]] • [[Special:Contributions/Ck.mitra|contribs]]) </small> <!--Autosigned by SineBot-->
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== Unscientific voltage table ==
The "33 Ω" row and the table caption "Open circuit, zero-load voltage and voltage for a 33 Ω load (330 mW) vs capacity" are nonsense unless cell capacity or discharge rate (current/capacity) used is stated. <!-- Template:Unsigned IP --><small class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/83.209.123.250|83.209.123.250]] ([[User talk:83.209.123.250#top|talk]]) 22:56, 23 February 2018 (UTC)</small> <!--Autosigned by SineBot-->
:I've added the battery size (AA), and changed the 33 ohm to 330 mW. Without the full context the 33 ohm made no sense (the battery was powering a boost converter, and the 33 ohm load was connected to the output of the converter, not to the battery). At 1.5V, a 33 ohm load would only draw 68mW. [[User talk:Prevalence|<span style="color:DarkGreen;background-color:#EAEAEF;">Prevalence </span>]] 19:59, 12 May 2019 (UTC)
== Remove Edison as inventor ==
Edison didn’t invent the NiFe battery, this was invented by Jungner as well with the first patent registered in 1897 four years prior to Edison. <!-- Template:Unsigned IP --><small class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/83.233.2.6|83.233.2.6]] ([[User talk:83.233.2.6#top|talk]]) 20:31, 17 February 2020 (UTC)</small> <!--Autosigned by SineBot-->
== Incorrect illustration. ==
[[File:Alkaline-battery-english.svg|thumb|right|Section through an alkaline battery.]]
The illustration to the right is incorrect on two counts and has been removed from the article.
#It shows the cell as containing manganese oxide. This is wrong: it is manganese ''di''oxide. Manganese oxide would be totally useless as it is one of the products of the overall reactions. This is most probably a typo and should have read 'manganese dioxide'.
#Even if labelled correctly, it shows that the manganese (di)oxide as the cathode of the cell. This is incorrect.
The Manganese dioxide takes no part in the production of electric current. It couldn't even if it wanted to because it is a complete non conductor and as such cannot conduct current into or out of the cell. All the equations are incorrect for the same reason. In any primary cell, the cathode actually takes no part in the reaction at all. It merely serves as a conductor (which manganese dioxide isn't) to allow the developed electron flow to flow back into the cell. The choice of cathode material does affect the E.M.F. of the cell because there is a potential between the cathode and the electrolyte. The manganese dioxide serves no purpose other than as a depolariser to convert the hydrogen produced at the cathode's surface into water. Indeed, if the manganese dioxide were to be removed from the cell completely, it's E.M.F. would be exactly the same, except the cell would polarise as the current would rapidly drop as the gaseous hydrogen formed at the cathode would block the current flow. This is the problem that the depolariser (manganese dioxide) is there to solve.
For some reason modern textbooks insist on combining the two separate reactions into one giving the erroneous impression that the manganese dioxide is part of the current producing reaction - it isn't.
The hydrogen oxidation reaction is separate from the electrochemical reaction and is.
2MnO<sub>2</sub> + 2H --> Mn<sub>2</sub>O<sub>3</sub> + H<sub>2</sub>O (Note: 2H ''not'' H<sub>2</sub> as the hydrogen produced does not get to form a molecule before being grabbed by the MnO<sub>2</sub>)
This needs to be removed from the electrochemical equations to make them correct. [[Special:Contributions/86.134.23.220|86.134.23.220]] ([[User talk:86.134.23.220|talk]]) 12:21, 23 March 2021 (UTC)
:2MnO<sub>2</sub> + 2H --> Mn<sub>2</sub>O<sub>3</sub> + H<sub>2</sub>O (Note: 2H ''not'' H<sub>2</sub> as the hydrogen produced does not get to form a molecule before being grabbed by the MnO<sub>2</sub>)
:Unfortunately you are wrong; but your point #1 is appreciated. It should be MnO<sub>2</sub>
:Your above equation is wrong because you do not show from where the two protons come.
:The original equations are correct because the two electrons travel via the external circuit. The porous membrane allows transport of protons to allow charge balance. chami 17:40, 28 October 2022 (UTC) <!-- Template:Unsigned --><small class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Ck.mitra|Ck.mitra]] ([[User talk:Ck.mitra#top|talk]] • [[Special:Contributions/Ck.mitra|contribs]]) </small> <!--Autosigned by SineBot-->
== Incorrect chemistry - should be MnOOH? ==
I'm not sure if this is incorrect, since I don't know all that much about electrochemistry, but I was looking into alkaline batteries and found several sources<ref>https://data.energizer.com/pdfs/alkaline_appman.pdf</ref><ref>https://www.osti.gov/servlets/purl/1529287</ref><ref>https://www.ill.eu/users/instruments/instruments-list/d1b/examples/why-cant-alkaline-batteries-be-recharged</ref> suggesting that MnOOH (or H<sub>x</sub>MnO<sub>2</sub> for the last one) rather than Mn<sub>2</sub>O<sub>3</sub> is produced at the MnO<sub>2</sub> electrode. I can guess that MnOOH might decay into Mn<sub>2</sub>O<sub>3</sub>, but it still seems misleading to just describe Mn<sub>2</sub>O<sub>3</sub> being formed if that isn't what's actually going on. Can someone who has a better understanding of this than I do please check this? I don't want to just edit it when I don't have a firm understanding of what's going on, especially since I also found a source claiming both that the given equation is correct and that the cathodic reaction on discharge is "not possible to describe [...] in a simple unambiguous way"<ref>https://www.doitpoms.ac.uk/tlplib/batteries/batteries_alkaline_mno.php</ref>. [[User:CuriousEnzyme|CuriousEnzyme]] ([[User talk:CuriousEnzyme|talk]]) 13:06, 1 June 2021 (UTC)
{{reflist-talk}}
negative terminal) is made of zinc powder (which allows more surface area for increased rate of reaction therefore increased electron flow) and the cathode (positive terminal) is composed of manganese dioxide." I just opened a big stack of them, the zinc is the solid outer casing, cathode. Then the manganese powder, then the carbon rod, anode button. I'm attempting to make electroluminescent & glow in the dark materials. Zinc casing dissolved in sulphuric, reduced to sulphide ==
negative terminal) is made of zinc powder (which allows more surface area for increased rate of reaction therefore increased electron flow) and the cathode (positive terminal) is composed of manganese dioxide."
I just opened a big stack of them, the zinc is the solid outer casing, cathode. Then the manganese powder, then the carbon rod, anode button.
I'm attempting to make electroluminescent & glow in the dark materials. Zinc casing dissolved in sulphuric, reduced to sulphide [[Special:Contributions/196.188.180.145|196.188.180.145]] ([[User talk:196.188.180.145|talk]]) 21:00, 27 March 2022 (UTC)
== The construction section has no citations ==
The construction section has no citations yet makes some bold claims [[Special:Contributions/2406:2D40:4092:9310:D05F:DAAD:7EC2:CD51|2406:2D40:4092:9310:D05F:DAAD:7EC2:CD51]] ([[User talk:2406:2D40:4092:9310:D05F:DAAD:7EC2:CD51|talk]]) 09:37, 23 April 2024 (UTC)
== The two half-reactions and the overall reaction ==
In section "chemistry", the overall reaction is not the sum of the two half-reactions, at least in the form they are reported there. I am aware that there is some uncertainty about the nature of the reduction product (MnOOH, Mn2O3, etc.) of manganese dioxide, but there should be formal consistency between the half-reactions and the overall reaction. [[User:Ekisbares|Ekisbares]] ([[User talk:Ekisbares|talk]]) 21:15, 22 July 2024 (UTC)
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