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Old 28 May 2007, 06:23 PM
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Glasses Distilled water for car batteries?

Comment: Car batteries
are typically made using lead/acid technology. I have heard that to get
the best performance from your battery, you should keep the cells filled
using DISTILLED water. I have also heard that regular TAP water is OK
because the battery will die long before the minerals in the water can
plate out on the battery surfaces and lower the battery's performance. I
don't know if that last statement is correct or not, but I heard last
night that adding tap water to a battery will cause it to explode.
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  #2  
Old 28 May 2007, 06:57 PM
Nappy Solo Nappy Solo is offline
 
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Technically, distilled water is the better choice, but if tap water made batteries explode, I would have been blind, dead, etc. back about 1970. Most batteries today are sealed "no maintenance" types, and do not require water to be added to them. I know if I post that, someone will counter with the fact that even those type can have the larger square caps pulled off them to check the water, but that really doesn't mean much, becuase they don't vent to the atmosphere. Most will last 3-4 years, and never need a thing done to them, save cleaning the terminals from time to time, and even that isn't much of an issue anymore. I've had a few motorcycle batteries that still have removable caps on them, and they, along with small tractor batteries, would benefit from distilled water. Not so much that they would last longer, but all tap water is not created equal - some contain a huge amount of crap and minerals. Lake water probably not good, either! BTW, most mc batteries are going to either gel or AGM - absorbed glass mat, and not only are sealed and need no maitenance, but outperform and outlast the old conventional lead-acid types that are not sealed, and vented to the atmosphere. That means the little clear plastic tube is gone, along with the potential for spewing acid on chrome exhaust, paint, etc. Technology and materials are greatly improved just in the last few years.

My older sister, did hook up jumper cables from her '58 Olds to a positive ground MG, and although I wouldn't call it an explosion, there was a loud bang, and her battery got a big split in one of the cells, and nasty acid everywhere. That's the closest I've seen anyone get hurt, but bad things do happen when jumping cars - frozen batteries, hooking up things wrong, etc.
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  #3  
Old 28 May 2007, 07:18 PM
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TrekkerScout TrekkerScout is offline
 
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While I would consider the likelihood of a battery exploding from adding tap water is quite low, I can see where there could be the possibility of an explosion. Most tap water contains chlorine. The chlorine could degas into the battery and combine with hydrogen gas (which is a normal byproduct of a lead/acid battery). If these two gasses in the proper concentrations come into contact with an ignition source (UV light, electric spark, sharp impact), it could result in an explosion.
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Old 28 May 2007, 09:34 PM
jimmy101_again jimmy101_again is offline
 
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Quote:
Originally Posted by TrekkerScout View Post
While I would consider the likelihood of a battery exploding from adding tap water is quite low, I can see where there could be the possibility of an explosion. Most tap water contains chlorine. The chlorine could degas into the battery and combine with hydrogen gas (which is a normal byproduct of a lead/acid battery). If these two gasses in the proper concentrations come into contact with an ignition source (UV light, electric spark, sharp impact), it could result in an explosion.
Not really. Chloride in the water can generate chlorine gas but if there is no chlorine you generate oxygen gas instead. Really not much difference in the reactivity of chlorine and oxygen. So ommiting chlorine from the system really doesn't make any difference. Hydrogen + oxygen will explode (if there is an ignition source) just as well as hydrogen + chlorine.
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Old 28 May 2007, 09:44 PM
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Eddylizard Eddylizard is offline
 
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I would have thought that (as Nappy Solo pointed out), given the various minerals and other stuff in tapwater, that there may be a good chance of depositing a layer of minerals (say limescale) on the lead plates either as a result of the electrolytic process, or as evaporative deposition (like your taps.) Thus making it harder for lead from the electrolyte to be re-deposited on the plates during the charging phase, and shortening the life of the battery.

Fairly moot, as I haven't seen a car battery that wasn't sealed and therefore didn't need topping up for years.
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  #6  
Old 28 May 2007, 11:06 PM
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Quote:
Originally Posted by Eddylizard View Post
Fairly moot, as I haven't seen a car battery that wasn't sealed and therefore didn't need topping up for years.
I don't know if I've ever seen a car battery that wasn't sealed, however when I worked as a groundskeeper when I was in high school, we had some electric golf carts whose batteries needed to have water added to them. This was over 10 years ago, and I don't know how old those golf carts were at the time.
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  #7  
Old 29 May 2007, 04:59 AM
PrometheusX303
 
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Quote:
Originally Posted by WildaBeast View Post
I don't know if I've ever seen a car battery that wasn't sealed, however when I worked as a groundskeeper when I was in high school, we had some electric golf carts whose batteries needed to have water added to them. This was over 10 years ago, and I don't know how old those golf carts were at the time.
Dude, who are you?
I also worked at a golf course for a few months while in high school. We used distilled water in the golf cart batteries. I suppose the impurity buildup would be much greater in rechargeable batteries.
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  #8  
Old 29 May 2007, 06:23 AM
Troberg Troberg is offline
 
 
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Another one who only use tap water here, without any problems.
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  #9  
Old 29 May 2007, 09:21 AM
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slightly OT, but I have the original battery off my bike, circa. 1953. The case is still solid and I'm wondering how difficult it would be to restore it (fully understanding the hazards of dealing with acid and the like).
I can buy comparable 6v motorcycle batteries here "dry"...i.e., the acid is added after purchase. Could I feasibly just swap out the plates and electrodes in my garage ?
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  #10  
Old 29 May 2007, 04:16 PM
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WildaBeast WildaBeast is offline
 
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Quote:
Originally Posted by PrometheusX303 View Post
Dude, who are you?
I also worked at a golf course for a few months while in high school. We used distilled water in the golf cart batteries. I suppose the impurity buildup would be much greater in rechargeable batteries.
I actually didn't work for a golf course. I worked for a wealthy local businessman maintaining his summer home. We used water from the hose in the golf cart batteries, btw.
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  #11  
Old 29 May 2007, 04:42 PM
PrometheusX303
 
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Quote:
Originally Posted by WildaBeast View Post
I actually didn't work for a golf course. I worked for a wealthy local businessman maintaining his summer home. We used water from the hose in the golf cart batteries, btw.
Were they used often?

The golf course had gallons of distiled water just for the batteries. They get charged daily.
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  #12  
Old 29 May 2007, 04:45 PM
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WildaBeast WildaBeast is offline
 
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Quote:
Originally Posted by PrometheusX303 View Post
Were they used often?

The golf course had gallons of distiled water just for the batteries. They get charged daily.
As I recall they were charged every couple of days.
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  #13  
Old 29 May 2007, 09:20 PM
jimmy101_again jimmy101_again is offline
 
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Quote:
Originally Posted by charlie23 View Post
slightly OT, but I have the original battery off my bike, circa. 1953. The case is still solid and I'm wondering how difficult it would be to restore it (fully understanding the hazards of dealing with acid and the like).
I can buy comparable 6v motorcycle batteries here "dry"...i.e., the acid is added after purchase. Could I feasibly just swap out the plates and electrodes in my garage ?
I suspect it would kind of hard to refurbish the battery, but not impossible.

First problem is that the battery case was not designed to be opened. You will probably have to cut the case open near the top.

But first, decant the electrolyte from the battery and rinse it out with a couple of changes of water.

Find someplace that'll accept the old electrolyte (sulfuric acid with a fair amount of lead dissolved in it) and the rinse water and the lead plates you'll be replacing.

Cut open the case, remove the old plates. Find someplace that'll sell you new plates that are the correct size. I suspect that it is next to impossible to by suitable plates. (Unfortunately, you can't just use sheet of lead. Batteries use a spongy lead that has greatly increased surface area.)

Install the new plates, figuring out how to ensure that the individual cells are sealed, make the connections from plate to plate and to the posts.

Find a glue suitable for resealing the battery. Best bet is probably a solvent type glue that dissolves whatever kind of plastic the case is made of.

Refill the battery with fresh sulfuric acid.

TA DA! You have a rebuilt battery in the original case. Probably cost at least a couple hundred dollars to do it.
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  #14  
Old 29 May 2007, 11:08 PM
Rehcsif
 
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We have a drinking water system and I've always used that to top off the battery of our John Deere lawn tractor. I'm sure it's not distilled quality, but should be a lot more filtered than standard tap water.

-Tim
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