De-Ionised Water in Battery?

CaptainBob

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Not something I've ever even considered on my car - but cleaning out some old crud in a locker I found 2 litres of "de-ionised water for batteries"... should I be putting it in my batteries periodically?

Thanks!
 
De ionised water is what you should using to top up your batteries when necessary to maintain the electrolyte at the correct level, and always above the tops of the plates.

Distilled water is the alternative. Distilled is made by distillation, deionised is made by what is best described as a chemical process. Mostly deionised these days.

Either may be sold as battery top up fluid
 
Is the water from a dehumidifier during the winter different from the water from the same dehumidifier during the summer? I would have thought they would both contain traces of salt from working in a salty atmosphere.
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Artificial Intelligence is no match for Natural Stupidity
 
Dehumidier water won't contain salt unless salt water is sprayed around your cabin. Salt doesn't tend to evaporate much, so won't condense much on the dehumidifier.
The water in the dehum is likely to grow a bit of mold or green bits, so may not be ideal for the iron!
 
Water from dehumidifiers is not recommended.
I am with Cliff on this. I bet if I took a sample of water collected from a dehumidifier on board a boat into the lab and ran it through an ion chromatograph I would be able to measure the salt content.
 
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Water from your dehumidifier during the winter does the job. Handy for the ironing too.

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Have you ever tasted the water from a dehumidifier? It is anything but pure.

Water collected while de-frosting a freezer appears a lot better (at least to my taste buds).
 
We run a de-humidifier at home. We have an old (decrepit) cottage that can smell damp - usually in early Spring before the walls warm up. We use the water in the steam iron which has remained entirely lime scale free. We have very hard water in Bucks.

I presume it is lime scale that is the primary reason not to use tap water in batteries? My chemistry is sadly limited to 'O level.

PS: We've just had the ground floor of the house 'tanked'. So hoping to retire the dehumidifier!
 
Bob,

The frequency depends how hard/fast you charged the batteries. I would suggest that you check the level initially every three months, you will soon understand how much you are using.

You need to need to top up each cell to about 1/4" (that is 6mm if you are younger than 40) above the top of the plates. Do not fill them right up.

Tony
 
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So how often am I likely to need to top them up

[/ QUOTE ] Probably very infrequently but it does depend on the battery type and your charging rate. As they get older they will probably need more frequent topping up. SWMBO car is four years old and I have not topped its battery up yet!
 
Yes you need to check the water level in the batteries initially frequently then less frequently if you find they don't need topping up.
This of course assumes they are not the sealed type batteries which can't be checked.
Batteries use more water if they are agressively charged either by a mains type battery charger or enhanced charging regulator on the engine. (Stirling etc)
I think sometimes you can use tap water depending much on the purity of the tap water. Certainly deionised or distilled water is safer.
Rain water should be OK.
What amazes me is that in my super market distilled water is cheaper/ similar priced than bottled drinking water.

Check your batteries olewill
 
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