Deionised Water

[Blacken]

Can anyone tell me if a bottle of deionised water has a shelf life if it is rarely used?

I have had this bottle for about 10 years for the occasional battery cell top up and don't know if l should chuck it and get a new bottle or whether it is still ok. Always stored in cool environment with the cap on the bottle.

[Jonathan Kay]

It will be fine.

Jonathan

[Dorset7]

De-ionised water does have a shelf life -  DI water is, by its very nature and name, very low in ions and hungry for them. In time it will leach ions from the container and atmosphere, when exposed to it, and so becomes less and less de-ionized as time goes on. In reagent grade chemistry it may interfere with the result of a subtle and sensitive experiment but probably not be detrimental in garage use, although ten years is a while!

[gileshudson]

Use it up in your steam iron in the hosue and treat yourself to a new bottle for the grudge.
CarPlan De-Ionised water is just £1.15 from Tesco for 2.5litres.

 

[Blacken]

Thanks. Will take your advice.

[John Vine]

I agree with JK.

IMHO, your "old" DI water will be just fine for topping-up your battery, as what you're trying to avoid is introducing mineral ions like sodium, calcium, chlorides and sulphates.  As your bottle is sealed, the only source of these will be from the container, and the resultant levels of mineral ions will be infinitesimal (if not zero).

Personally, I top up with distilled water (obtained from my de-humidifier).

JV