Where to keep batteries?

[Mike90250]

Run 2" or 3" tube, always ascending, to vent the gas from the top of each bin.

OR

There is a company called Zephyrvent for PV battery arrays, with a 4" vent and brushless DC fan driven by the charge controller.

http://www.zephyrvent.com/

[SiL3nT]

As long as the batteries are stored in a cool dry place, you should be fine.

[russ]

A cool and dry place has nothing to do with a battery generating gas (hydrogen in particular).

[rimpa001]

We are looking around our garage to figure out were to put batteries associated with solar panels. A friend said the garage was a bad location due to the cement floor.

Is this actually true or is it a rumor?

What is the best place to keep your batteries?

You can place your batteries anywhere which is isolated from heat and is a cool and dry place..So you can go ahead with your idea of storing it in your garage..Thank you..

[russ]

The concrete floor thing is an old wives tale that seems to never go away.

Important though is a well ventilated location - with flooded cell batteries hydrogen can be generated and it needs to escape. It will go 'up and away' but could be trapped in an unventilated area.

Hydrogen is really quite safe but as with and thing of that nature the rules must be followed. You don't sit around throwing matches into a barrel of gas for a good reason - eventually one of them will not go out!

[Sunking]

I see no one has came up with the right answer yet.

Concrete is very conductive, so much so the NEC requires the steel reinforcement bar in you homes foundation to be used as one of the required ground electrodes.

If your system is designed and properly wired, one of your battery polarities (either positive or negative) is required to be grounded so the Over Current Protection Devices can operate.

Batteries get dirty, will spill over acid from time to time. This causes conductive paths to form from the terminals of the battery to the concrete, These paths allow current to flow. The current is not high enough to cause any real problems for you to notice visually like trip a breaker or blow a fuse, but it does drain the batteries

This problem is quite well know in the Telecom, electric utility, and Electric Vehicle industry. In Telecom and Utility industries batteries are installed on fiberglass racks on concrete floor to isolate then electrically, and in Ev's batteries are not grounded to the and are floated.

[dbldrew]

I see no one has came up with the right answer yet.

Concrete is very conductive, so much so the NEC requires the steel reinforcement bar in you homes foundation to be used as one of the required ground electrodes.

If your system is designed and properly wired, one of your battery polarities (either positive or negative) is required to be grounded so the Over Current Protection Devices can operate.

Batteries get dirty, will spill over acid from time to time. This causes conductive paths to form from the terminals of the battery to the concrete, These paths allow current to flow. The current is not high enough to cause any real problems for you to notice visually like trip a breaker or blow a fuse, but it does drain the batteries

This problem is quite well know in the Telecom, electric utility, and Electric Vehicle industry. In Telecom and Utility industries batteries are installed on fiberglass racks on concrete floor to isolate then electrically, and in Ev's batteries are not grounded to the and are floated.

Actually WizeWizard had the correct answer in post #2


From Trojan Battery...

"Storing a battery on concrete will discharge it quicker?- Long ago, when battery cases were made out of natural rubber, this was true. Now, however, battery cases are made of polypropylene or other modern materials that allow a battery to be stored anywhere. A battery's rate of discharge is affected by its construction, its age, and the ambient temperature. The main issue with storing on concrete is that if the battery leaks, the concrete will be damaged."

http://www.trojanbattery.com/Tech-Support/FAQ.aspx

[Sunking]

Actually WizeWizard had the correct answer in post #2


From Trojan Battery...

"Storing a battery on concrete will discharge it quicker?- Long ago, when battery cases were made out of natural rubber, this was true. Now, however, battery cases are made of polypropylene or other modern materials that allow a battery to be stored anywhere. A battery's rate of discharge is affected by its construction, its age, and the ambient temperature. The main issue with storing on concrete is that if the battery leaks, the concrete will be damaged."

http://www.trojanbattery.com/Tech-Support/FAQ.aspx

We are talking Apples and Oranges here. Your Trojan link is referring to storage, I am referring to operation.

Trojan link is correct about natural rubber cases because the old hard rubber cases had a high amount of carbon which is conductive, and the rubber was porous which when set on concrete would suck up moisture causing the batteries to discharge over time. However that is not what I am referring to.

As batteries sit in operation they are constantly charged and discharged which cause the acid to boil and evaporate. The acid collects and builds up on the battery cases, and this cause dirt and other contaminants to build up which cause conductive paths to some of the cells.

In a battery off-grid system you are required to ground one of the battery polarities. Concrete is an excellent conductor and you homes foundation rest on earth. So with one of the batteries polarities ground completes a conductive path which can cause the batteries to self discharge.

As stated before the Telecom, utility, and Electric Automotive industries are all aware of this unique problem and have standards to prevent it from happening.

One way you can verify this is check a golf cart out. The battery is not bonded to the frame/chassis.

[dbldrew]

We are talking Apples and Oranges here. Your Trojan link is referring to storage, I am referring to operation.

Trojan link is correct about natural rubber cases because the old hard rubber cases had a high amount of carbon which is conductive, and the rubber was porous which when set on concrete would suck up moisture causing the batteries to discharge over time. However that is not what I am referring to.

As batteries sit in operation they are constantly charged and discharged which cause the acid to boil and evaporate. The acid collects and builds up on the battery cases, and this cause dirt and other contaminants to build up which cause conductive paths to some of the cells.

In a battery off-grid system you are required to ground one of the battery polarities. Concrete is an excellent conductor and you homes foundation rest on earth. So with one of the batteries polarities ground completes a conductive path which can cause the batteries to self discharge.

As stated before the Telecom, utility, and Electric Automotive industries are all aware of this unique problem and have standards to prevent it from happening.

One way you can verify this is check a golf cart out. The battery is not bonded to the frame/chassis.

Trojan addressed the acid leaking,

[Sunking]

Energy can in fact "leak" out of battery banks — though in different ways. The first is from current between the battery terminals, caused by dirt, dust, and grime becoming carbonized (and therefore electrically conductive) from acid released from the cell.

Thank you. very much, you just proved my point. Not only can the concustive paths form between terminals, they can also form through the concretete if placed on it. I am not saying you cannot or shouldn't place them on concrete, just be aware of the potential problem. Moral of the story is keepem clean.

[dbldrew]

Thank you. very much, you just proved my point. Not only can the concustive paths form between terminals, they can also form through the concretete if placed on it. I am not saying you cannot or shouldn't place them on concrete, just be aware of the potential problem. Moral of the story is keepem clean.

How did I prove your point? That article said it wont happen on concrete but will happen between terminals, that disproves your point that the concrete is the problem.

Here is a quick test most can do, take an ohms meter and test a piece of aluminum, now test your concrete floor, notice the difference? If the commercially sold aluminum solar battery racks don

[Sunking]

How did I prove your point? That article said it wont happen on concrete but will happen between terminals, that disproves your point that the concrete is the problem.

Of course it proves it. The same dirt and deposits that cause conduction between the terminals can and will cause conduction between the terminals and concrete. It is a known fact, and why the utilities have written standards to combat the problem.

[Sunking]

Here is a quick test most can do, take an ohms meter and test a piece of aluminum, now test your concrete floor, notice the difference? If the commercially sold aluminum solar battery racks don’t cause problems why would the concrete floor?

Because concrete is highly conductive, and by code you have to use the re-bar in the concrete as a ground electrode. The re=bar has a very high surface contact area with the concrete, and the concrete has a very high surface area contact with earth. To be technically correct it forms a concrete encased electrode aka UFER ground.

Try this test as it is valid and will clearly demonstrate the point. If your main AC service panel is in your garage, or you have an AC receptacle in your garage take off your shoes and socks so you have bare feet. Then take off the cover of your AC panel and touch one of the phases with your finger, or do the same by sticking a small screw driver in the wall socket with your hand touching the metal part of the screw driver. Then see what happens? Bet you will conclude concrete is a very good conductor.

[dbldrew]

It is a known fact, and why the utilities have written standards to combat the problem.

Is it the same fact that all the battery manufacturers are referring to as a Myth?

[dbldrew]

Because concrete is highly conductive, and by code you have to use the re-bar in the concrete as a ground electrode. The re=bar has a very high surface contact area with the concrete, and the concrete has a very high surface area contact with earth. To be technically correct it forms a concrete encased electrode aka UFER ground.

Try this test as it is valid and will clearly demonstrate the point. If your main AC service panel is in your garage, or you have an AC receptacle in your garage take off your shoes and socks so you have bare feet. Then take off the cover of your AC panel and touch one of the phases with your finger, or do the same by sticking a small screw driver in the wall socket with your hand touching the metal part of the screw driver. Then see what happens? Bet you will conclude concrete is a very good conductor.

Yes using the re-bar as a ground is to protect against lightning strikes, lightning also strikes trees, should wood also not be used? Its completely different animal comparing the power of lightning and what it can flow through vs what a battery can flow power through.

Why not test it to prove all the battery manufactures wrong? Ground out a battery into your concrete floor and use a volt meter to see how much power is actually flowing into the concrete.