Can rain short out a battery

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polk county

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Can rain short out a battery? Can electricity flow from the negative post to the positive across a film of water on top of the battery? I dont think that current will travel across fresh water. Any ideas
 
dingbat

dingbat

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Re: Can rain short out a battery

polk county said:
Can rain short out a battery? Can electricity flow from the negative post to the positive across a film of water on top of the battery? I dont think that current will travel across fresh water. Any ideas
Click to expand...

If it was pure water it has very little conductivity but your typical rain fall is high in metallics and salts and would be conductive
 
J

joed

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Re: Can rain short out a battery

It wouldn't short it out as piece of wire would. It could cause a slow drain and empty the battery over time.
 
Woodnaut

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Re: Can rain short out a battery

Dirt and grime oftentimes accummulates on the tops of batteries. When it gets wet it can form a leakage path - I've definitely seen this before. As previously mentioned, it's not a dead short, but it can be a very slow drain. If a boat sits up for several days or a few weeks, it can can knock the battery down. Just keep the battery top (and sides if you have side posts) wiped off every now and then it'll be no problem.
 
jtexas

jtexas

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Re: Can rain short out a battery

pure water isn't a good conductor, but you hardly ever encounter pure water.

Want to find out for sure? Stick the probes of your ohmmeter into a cup of water.
 
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masterge

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Re: Can rain short out a battery

polk county said:
Can rain short out a battery? Can electricity flow from the negative post to the positive across a film of water on top of the battery? I dont think that current will travel across fresh water. Any ideas
Click to expand...

If there is a complete path of water from the positive terminal to the negative terminal, it will be just like taking a wire from one side to the other. However, having this occur in an enclosed battery compartment would be rare.

Oh by the way, water is an extremely good conductor of electricity whether pure or impure.
 
tashasdaddy

tashasdaddy

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Re: Can rain short out a battery

buy a battery box, and quit worrying. it should be in one anyway.
 
M

masterge

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Re: Can rain short out a battery

polk county said:
Can rain short out a battery? Can electricity flow from the negative post to the positive across a film of water on top of the battery? I dont think that current will travel across fresh water. Any ideas
Click to expand...


I = E/R

Current is directly proportional to voltage and indirectly proportional to resistance.

There is minimal to no resistance when there is a continuous low resistance path between the + and - battery terminals. Standing water on top of a battery will do this if it makes a complete path. With low to no resistance, current value increases quite a bit. We in the business call this situation a short.


Yes, salt water and water with more contamination in it will normally conduct better than freshwater, but all water will conduct.

Bottom line is that you can't argue with the formula. Oh yea, the guy that said to get a battery box has the right answer.
 
JCF350

JCF350

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Re: Can rain short out a battery

masterge said:
Oh by the way, water is an extremely good conductor of electricity whether pure or impure.
Click to expand...

Pure H2O has no free electrons and is an insulator. If it conducts electricity it has impurities in it.
 
bruceb58

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Re: Can rain short out a battery

masterge said:
I = E/R

Current is directly proportional to voltage and indirectly proportional to resistance.
Click to expand...

I think you mean inversely proportional.

Rain is not going to short out a battery. If there is a ton of deposits on the top of the battery, you may get a slight drain that might drain your battery in a month if it got wet but nothing that is going to "short" it out.
 
jtexas

jtexas

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Re: Can rain short out a battery

a vulture, a rabbit and an iguana walk into a bar...........
 
jtexas

jtexas

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Re: Can rain short out a battery

JCF350 said:
:eek:And and and.....:confused::confused:
Click to expand...

I = V / R the iguana sees the vulture over the rabbit
R = V / I the rabbit see the vulture over the iguana
V = R * I the vulture sees the rabbit & iguana side by side
 
JCF350

JCF350

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Re: Can rain short out a battery

Seems like a lot of work just to manipulate an equation. :)
 
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