# Stench from lead acid battery

**URL:** <https://boards.straightdope.com/t/stench-from-lead-acid-battery/370485>\
**Category:** Factual Questions\
**Created:** [August 28, 2006, 2:14am UTC](https://boards.straightdope.com/t/stench-from-lead-acid-battery/370485 "2006-08-28T02:14:33Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![dauerbach](https://avatars.discourse-cdn.com/v4/letter/d/c2a13f/32.png) [@dauerbach](https://boards.straightdope.com/u/dauerbach)\
**Post date:** [August 28, 2006, 2:14am UTC](https://boards.straightdope.com/t/stench-from-lead-acid-battery/370485/1 "2006-08-28T02:14:33Z")

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My lawn tractor battery wouldn’t hold a charge and so I placed it on a trickle charger. This was months ago, but just recently and sulfury stench developed in the garage and I think I traced it to the battery. Is this possible? Can a constantly charging or overcharging battery give off a horrible odor?

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**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\
**Post date:** [August 28, 2006, 2:43am UTC](https://boards.straightdope.com/t/stench-from-lead-acid-battery/370485/2 "2006-08-28T02:43:55Z")

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Sure. The [redox potential](http://en.wikipedia.org/wiki/Redox_potential) for sulfate-\>sulfide (E[sub]0[/sub]’) is about -110 millivolts, and you’ve been feeding in 6 to 12 volts for months.

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**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\
**Post date:** [August 28, 2006, 4:12am UTC](https://boards.straightdope.com/t/stench-from-lead-acid-battery/370485/3 "2006-08-28T04:12:17Z")

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Yep. Overcharging can make the electrolyte boil and give off fumes. Chances are pretty good that your iffy battery has gone round the bend and is now unambiguously bad.

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**Author:** ![dauerbach](https://avatars.discourse-cdn.com/v4/letter/d/c2a13f/32.png) [@dauerbach](https://boards.straightdope.com/u/dauerbach)\
**Post date:** [August 28, 2006, 11:39am UTC](https://boards.straightdope.com/t/stench-from-lead-acid-battery/370485/4 "2006-08-28T11:39:51Z")

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Darn, and I my trickle charger was used in automatic mode. Perhaps the charger is bad as well.

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**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\
**Post date:** [August 28, 2006, 9:41pm UTC](https://boards.straightdope.com/t/stench-from-lead-acid-battery/370485/5 "2006-08-28T21:41:49Z")

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Sometimes, with luck, a dried battery can be revived by restoring the water. Often, though, chemical debris has established bridges between positive and negative plates. There are some engineer/conjurers in the world who can tell you how to overwinter a lead-acid battery without killing it. I’m not one of them.

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**Author:** ![robcaro](https://avatars.discourse-cdn.com/v4/letter/r/df705f/32.png) [@robcaro](https://boards.straightdope.com/u/robcaro)\
**Post date:** [August 28, 2006, 10:16pm UTC](https://boards.straightdope.com/t/stench-from-lead-acid-battery/370485/6 "2006-08-28T22:16:31Z")

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> [@AskNott](#):
>
> Sometimes, with luck, a dried battery can be revived by restoring the water. Often, though, chemical debris has established bridges between positive and negative plates. There are some engineer/conjurers in the world who can tell you how to overwinter a lead-acid battery without killing it. I’m not one of them.

Always replentish the water with “Distilled Water.”