Solar lead acid battery housing

[Ian Wallis]

Hello,
On my landing, I have found a dead space between the chimney breast and the main bedroom; there should be enough room to house my four solar powered lead acid batteries.


The concrete block chimney on the left and plasterboard to the back and right.

Here's question no'1, do I make the housing out of wood, wood with ceramic tiles? I'm guessing that the regulations will say 5ft of non combustible material on all sides

Question no'2, as lead acid batteries gives off hydrogen, do I need to vent this outdoors via a pipe, or will a louvre door be ok?

The chimney will be in use with a liner.



To my mind this is a perfect place to have the batteries, as it is central in the house, and will keep the cables to lighting nice and short.

Thank you for any advice.

 

[Bluejets]

I'd say it's the worst possible place to house them.
I'd be expexting an explosion from a spark or being gassed in my sleep apart from eye irritation and any form of clothing being acid affected.
Not only does it give off hydrogen gas but also the charge and discharge create an acid vapour which may need washing out from time to time..
Also do not store lead acid directly on contrete floor.
Find an external naturally well ventilated purpose made and secured enclosure and don't forget warning signs.

 

[ChosunOne]

Also do not store lead acid directly on contrete floor.
Find an external naturally well ventilated purpose made and secured enclosure and don't forget warning signs.

I have no disagreements with anything else you said, but that warning against storing lead-acid batteries on concrete is many decades out of date. Like many urban myths, it persists.
http://www.todayifoundout.com/index.php/2017/02/storing-car-battery-concrete-floor-drain/

 

[Bluejets]

I have no disagreements with anything else you said, but that warning against storing lead-acid batteries on concrete is many decades out of date. Like many urban myths, it persists.
http://www.todayifoundout.com/index.php/2017/02/storing-car-battery-concrete-floor-drain/

I disagree.
Instructables supporter I take it...??

 

[Martaine2005]

As a child I was always told NOT to sit on concrete floor for erm... medical reasons (piles).
Now I’m reading myths and old wives tales. Some are hilarious.

Martin

 

[ChosunOne]

Actually, I never heard of Instructables before you mentioned it. I was drawing on my experience back in the 80's when I was fairly new in the security alarm business, which had/has a lot of lead-acid batteries, mostly sealed lead-acid (SLA), and had/has a lot of turnover of said batteries.

I read a lot of manufactures' material about care and feeding of SLAs, but the caveat about never leaving them sitting on a concrete floor came by word-of-mouth, the primary source of urban legend. Neither I nor any of my fellow techs could figure out how sitting on concrete could drain or damage a battery.

Finally one of my co-workers unearthed an article in one of our trade magazines about some misunderstandings of SLAs. When the author got around to the concrete floor myth, he began by saying, "Now this one is weird." He had no idea where that idea had come from. Remember, the 80's was before the internet, so tracking an urban myth was a lot harder.

The best speculation he could come up with was that maybe the reason a battery had been left on a garage concrete floor to begin with was that it "didn't work" for some unknown reason (i.e., too new to be dead from age, and hadn't been {knowingly} drained, so shouldn't be so low on charge..?), and was set aside apart from the other batteries of known potential---on a garage floor, which is usually concrete. So when the battery had sat on the concrete floor for six months in a discharged state and was then tested, it didn't hold a charge---not surprising, if it's left untended in its discharged state, not good for lead-acid batteries---but the concrete floor maybe got the bad rap for the dead battery, because the real reason it got discharged back in the beginning was lost to history.

All that was sheer speculation, of course, (and probably wrong) but prior to Internet, the best he could come up with at the time. 35-40 years later, and a few minutes ago, I spent a few seconds on the internet and found the article I linked in my earlier post. I really didn't search any farther, because I was satisfied with the aforementioned site's explanation of the myth's origin. Like many myths, it started as fact that got outdated with progress.

I should probably mention that in my line of work, we had to switch out a lot of SLAs that had been discharged but for logistical reasons we had to leave systems with charged batteries---but we couldn't wait for several hours for the discharged batteries to charge. So we were compelled to put fresh (new) batteries in the systems, and took the "old" batteries (of varying ages) with us. This left us with a lot of used batteries SLA batteries with a wide variety of ages--some virtually new---that couldn't be re-used in our commercial capacity. One other tech and I collected a pile of these used batteries to play with--the other guy was a radio ham--and we did a lot of charging and extensive testing of those batteries to determine which could be used reliably and which were too far gone to be trusted.

And from time to time, we both left some of those batteries sitting on concrete floors for extensive periods--weeks or even months--in both charged and discharged states, and never noticed that it made any difference. You can leave a charged SLA battery unattended for months without damaging it, even if it's partially charged (I've never taken the time to test what percentage of charge it has to have, nor for just how long), but leaving it very low or completely discharged for too long (maybe 6-8 months?) will probably kill it---whether it's left on a concrete floor has nothing to do with it.

Of course, that's my (and my mate's) personal experience, and we haven't documented it and had it peer-reviewed (except with each other), so I don't expect anyone on this forum to take this as expert opinion. I'm just telling you the reason I haven't questioned the aforementioned linked article, nor done any further research.

If you or anyone else here have a source that does give a reason that lead-acid batteries shouldn't be stored on concrete floors, I'm open to being enlightened.

EDIT: All that being said, I agree that while all that dead space in the OP's wall is tempting, it would be one of the worst places to leave lead-acid batteries, for most of the reasons you mention.

 

[Ian Wallis]

I'm surprised that venting is not an option, ho hum.
How about two of these AGM batteries in the wall space? Still a no no?

I resign my self to making a battery house outside that is well vented.
But how do I keep the batteries from shorting out when the fog and mist rolls in?
Can you reccomend a battery box that will keep them dry?

 

[Harald Kapp]

Fog and mist shouldn't be an issue as long as no condensation occurs. Starter batteries in a car regularly survive under these conditions.

 

[Ian Wallis]

Yes I did think about a car battery, I convinced my self all would be ok, but yesterday all my batteries in my garage were soaking wet.
Puddles of water over the tops & beads along the sides. Looks like a bathroom shower has been used on them.
Living in a valley is the problem. Thick pea soup comes in through the cracks around the garage door.

I was wondering if there was anything on the market that would help with this.
Maybe just use a boat battery box with greese over the contacts?

 

[Harald Kapp]

Grease will definitely help.
You might also set up a small heater that is turned on when relative humidity exceeds say 80 % for example).
Setting up the batteries at a slight angle may also help to avoid the collection of water as puddles on top of the batteries. 5 to 10 degrees should allow the water to flow off the top. This is just an idea, by no means tested.

 

[Ian Wallis]

And how about the AGM batteries, are they too to be kept outside?
After all, don't fire & burglar alarms have them indoors?

Thank you all for your help, I do appreciate it.

 

[ChosunOne]

And how about the AGM batteries, are they too to be kept outside?
After all, don't fire & burglar alarms have them indoors?

Yes, burg/fire alarm systems usually have the SLA/AGM batteries for the Control Panel (the system "brain" using the battery, not the keypad) inside a steel cabinet in some out-of-the-way place, e.g., an unfinished basement or utility area housing a water heater or furnace, or a utility closet. Generally installers try to avoid laundry rooms or any space where water condensation or excessive heat might occur. I've seen them installed close to furnaces, but never next to a fireplace. And be mindful of where your water pipes are. I've seen thoughtless installations where a leaking pipe joint trashed the system Panel.

SLAs do occasionally leak from overcharging or just age, but generally don't have that problem if they're well-maintained. Putting them somewhere accessible to inspection is a good idea, which argues for keeping them inside somewhere. (Right at this moment, it's below freezing outside where I am, which would discourage me from inspecting anything housed outside my warm walls.) Generally the slight venting of acid vapor only causes corrosion at the terminals over a long period. And of course, you won't need to put your batteries in a cabinet like I do.

 

[Ian Wallis]

Excellent, my work hasn't been wasted.
These AGM's indoors will do for LED lighting (I may need a couple more), and with the lead acid outside for laptops & modems etc we'll be all setup for when the power cuts come along.
Next job, fit a log burning stove

 

[hevans1944]

As a child I was always told NOT to sit on concrete floor for erm... medical reasons (piles).
Now I’m reading myths and old wives tales. Some are hilarious.

Martin

Once, while I attended grade-school in the 1950s, our teacher asked us (the students in her class) to clip and bring to class for "show and tell" an article-clipping that said something about science. This was, IIRC, right after the Ruskies shocked the world by orbiting the first man-made satellite, Sputnik. All Sputnik ever did was emit beeps, but anyone in the world with a wide-band radio receiver could hear those beeps. Plus One for the Soviets. This event heated up the Cold War somewhat and briefly pushed Science to the forefront of the U.S. educational system. That's Science with a capital S for big science, since only governments could afford to do big science.

So, being innocent and eager to please my teacher, I found and brought to school this small advertisement for Preparation H (I didn't know then what that was) that shouted out in bold print: SCIENCE SHRINKS PILES WITHOUT SURGERY!

What's not to like about that, I thought? In one sentence my "article" managed to cover "science," "medicine," and a "discovery for shrinking piles" (whatever those were). For a short while I was the laughing stock of that class... maybe the whole damned school, because we lived in a rural to semi-rural area and everyone in class, except for yours truly, knew exactly what "piles" were. And the incident somehow got back to my mother, who eventually set me straight on the difference between a real science article and an advertisement that exploited the name of science to sell a product. Not a whole lot different from what we have today with infomercials and ads on the Internet disguised as news articles or real opinion pieces.

As for concrete floors... as a child, AFAIK, no one mentioned the dangers of sitting on them. However, Dad always told me and my brother, "Sh!t or get off the pot!" which may have had some relevance to the advice of not sitting on concrete.

@Ian Wallis: What power cuts are you expecting? Now that GB is free of European influence via Brexit, there should be smooth sailing for the rest of this century. Pound Sterling will once again soon be represented by real silver. Uh, about the same time the petrodollar is represented by gold instead of oil. And, say, aren't you the guys building windmills in the North Sea and the Atlantic Ocean to supply electricity to the mainland? And has anyone thought about a coalition among Canada, Australia, and India? Lots of things to think about, moving forward!

As for log-burning stoves... are there still trees left in England, Ireland, or Scotland? Coal-burning is much more efficient than wood-burning, and there should be some of that left somewhere. A bit messy though.

 

[Ian Wallis]

In the UK during WW I & II, food rationing was imposed and we had to import food from all over the world. We just couldn't grow enough food to sustain our populations needs.
Today we have addressed the balance to a degree with intensive farming with all it's nasty ways.
But we still import 50% of our food.
The population of the UK during WW I & II was a lot less than it is now. At a guess I would say five or six times more now due to growth and immigration.
So we see that if the world for what ever reason, stopped selling food to us, then we would see civil unrest much larger than we are seeing today.
But why am I talking about food when I should be talking about electricity? I'm getting there.

A series of events has caused western economies to drastically shrink.
We no longer manufacture and export, so unemployment is up, and so circulation of those lost earnings can not be taxed, further damaging our economy. Some twelve years ago the collapse of Lehman Brothers in the USA and Northern Rock in the UK was a noticeable start of our decline. Prime minister Gordon Brown sold off load of our gold reserves which haven't been replaced.
Continuous banker bail outs had to be paid for somewhere, and it was temporally paid for by devaluing the pound by money printing. This money printing is just a debt holding system. The UK is 2+ trillion in debt, and all western countries has its similar problems.
What I'm saying is at the end of the line we will have a recession that will become depression.
Mass unemployment, deflation of currency = inflation of prices in the shops, strikes lay offs, riots, power cuts, food unavailability and eventually Wiemar Republic (1930's Germany).

Yep, I think the lights are going to be off

 

[dave9]

The (now) myth about not storing batteries on concrete floors goes back to when they had wood or metal rather than plastic casings. The moisture that could be present, could either conduct and drain the battery if metal, or swell the wood. Plastic has neither of these problems.

I don't think the spot you've chosen is a good one but some concerns would be reduced if you used both a vent pipe AND a fan forced airflow through it so the area is negatively pressurized to keep all fumes pulled outside. Keep in mind that your fan ought to be rated for this type of exposure, and you could even consider putting two in series so that if one fails, you still have airflow till you notice and replace it.

You will greatly reduce the outgassing of the batteries if your charge controller does its job well and does not overcharge them. However, I and many other people in my area, have basements and sumps and battery backup sump pumps with standard deep cycle wet cell lead acid batteries in the basement, no vapor barrier between this area and the rest of the living area, and have not experienced any corrosion, explosions, or any other ill effects. Granted that is just ONE battery, so if there is a trace amount of problem that I haven't detected in many years of service, multiply that by # of cells you are using, but still, I have bare metal objects pretty nearby, and zero corrosion on them or the battery terminals in the humidity and temperature controlled basement where it is.

That battery is a few years old and I did have to add, maybe 3 oz of water for the first time this year, so it is outgassing slightly, but as mentioned above, not enough to matter, IMO. Then again, I might not have checked the water level when it was brand new and hadn't checked that a single time yet, so it is possible it was bought already 3oz below where I thought it should be!

 

[roughshawd]

I have found that lead acid batteries do real well in cold environments, but not so good when they get warm. Assuming you are just wanting 12v, you might find a nearby 110 line and put in a converter, they are much more reliable than batteries, but if you are wanting to put in a "POWERSOUT" battery system in the wall, you should first decide what kind of re-charging system you are going to put in, and how much backup power you are intending on having!!

 

[hevans1944]

I have found that lead acid batteries do real well in cold environments, but not so good when they get warm.

What you think you have found about lead-acid batteries is not in any way true. No battery does real well in cold environments for the simple reason that ALL chemical reactions slow down as their temperature decreases.

While it is true that excessive temperature will have the detrimental effect of increased lead sulfation on lead-acid energy production, in general the effect of cold ambient temperatures is far greater. For a demonstration, leave your fully-charged (at normal room temperature) lead-acid battery outside, overnight, in temperatures approaching -40F and then try to start a reasonably large engine. Report back here on the results.

 

[Harald Kapp]

you might find a nearby 110 line and put in a converter,

That is not the issue here. The OP wants to use he batteries as a backup for his solar power installation:

there should be enough room to house my four solar powered lead acid batteries.