[saket77]

Dear BHPians,

I have a simple home inverter set up since last 3 years. The problem is that the battery with the UPS inverter unit is installed in my dining room, where if I step from outside, I get a hint of the typical acidic smell of a charged battery; which I think is detrimental to one's health. The dining area is enclosed with one huge window.
Can you guys please suggest if there is any way out to keep the fumes of the battery away?

Thanks!

[R2D2]

Originally Posted by Thad E Ginathom

Gentlemen, if a fan is installed near the batteries, it's it free from spark risks?

Generally exhaust fans have brush-less motors (like ceiling fans) which do not spark inside the motor housing. I've seen these running in battery rooms.

However, switching an appliance/fan on and off may cause a spark so the switch should be placed outside the room at a suitable location protected from the elements.

Originally Posted by saket77

The dining area is enclosed with one huge window. Can you guys please suggest if there is any way out to keep the fumes of the battery away? Thanks!

Battery gasses can be corrosive and can affect respiratory tissues. We also had a similar problem where my Dad had the battery and inverter located in the kitchen near the main switch board. Unfortunately the battery case had a small crack and it started leaking electrolyte. I had the battery replaced and the entire set relocated to another room on the terrace.

It's better to keep the batteries as isolated as possible away from normally inhabited or used rooms especially if you have small children in the house

[prithm]

Originally Posted by saket77

Dear BHPians,

I have a simple home inverter set up since last 3 years. The problem is that the battery with the UPS inverter unit is installed in my dining room, where if I step from outside, I get a hint of the typical acidic smell of a charged battery; which I think is detrimental to one's health. The dining area is enclosed with one huge window.
Can you guys please suggest if there is any way out to keep the fumes of the battery away?

Thanks!

My dear sir,

Hope the inverter guys did not warn you of this. Typical salesmen.

Remove the battery out of your house ASAP and keep it away from children. The set up that you see from my previous post is all to keep it away from home, kids, parents and pets as far as possible. As R2D2 and Aroy were suggesting, a ventilation system is good to have for such enclosed set up. Although I did not factor the ventilation fan, now I am actually doing it.

As you rightly said, yes its detrimental health and possible safety hazard too when inside the house. The fumes originate more during recycling and discharge phase.

You can get one of these small fans (computer cabinet ones) and get the local electrician fix a appropriate socket for this and fix it in your trolley (if you are going to use it going forward.

[R2D2]

Originally Posted by prithm

You can get one of these small fans (computer cabinet ones) and get the local electrician fix a appropriate socket for this and fix it in your trolley (if you are going to use it going forward.

He (@ prithm) would need a slightly larger preferably AC fan since he has 4 batteries and a way larger volume of corrosive gas to exhaust out of the room. The one in the photo is a 12 V DC fan used for computer cabinets which represents a smaller volume of air to be driven out of an enclosed space.

Maybe multiple fans would do but in my experience (with PC water cooling etc) it is better to have 1 big fan rather than 2 small ones. For e.g. a single 200 mm AC fan would do better than 2 x 120 mm 12 DC parts. Also be aware these computer fans also have varying CFM throw values and noise levels that differ from model to model.

And yes, then there's the longevity factor. Except for good quality computer case fans (roller, fluid dynamic or magnetic levitation bearings) that are expensive @Rs 1000+ per fan , the cheaper ones (sleeve bearing) give up the ghost after a couple of years. Contrast that with heavy duty AC exhaust fans which cost less overall that can run 5-10 years with a 24x7x365 duty cycle without breaking a sweat.

@prithm, for suggestions look at this range: Havells' Exhaust fans

PS - For @saket77, the best option is to relocate the battery + inverter set.

[Thad E Ginathom]

Originally Posted by R2D2

Generally exhaust fans have brush-less motors (like ceiling fans) which do not spark inside the motor housing. I've seen these running in battery rooms.

However, switching an appliance/fan on and off may cause a spark so the switch should be placed outside the room at a suitable location protected from the elements.

Thanks.

Battery gasses can be corrosive and can affect respiratory tissues.

Hmmm... for quite a long time I had a jewellery workshop in the corner of my bedroom, including dilute sulphuric-acid in an old mug. I guess it might not have been such a good idea. Mind you, I think the air in the room was less corrosive than the "fresh" air where I live now!

[R2D2]

Originally Posted by Thad E Ginathom

Hmmm... for quite a long time I had a jewellery workshop in the corner of my bedroom, including dilute sulphuric-acid in an old mug. I guess it might not have been such a good idea. Mind you, I think the air in the room was less corrosive than the "fresh" air where I live now!

Batteries are corrosive because of the gasses they vent during the charging phase. The dilute acid (normally 35:65 acid to distilled water ratio) is pretty benign as long as it does not leak or touch some object other than plastic or glass. Of course it has that ever pervasive sulphurous smell which TBH I find quite unpleasant.

Just keeping a container of dilute sulphuric acid shouldn't be too bad unless of course one touched the acid or if it were accidentally spilled. A capped container/bottle is a solution. But I would certainly not have one of these dangerous chemicals in my BR since there would be the small issue of my wife wanting to scalp me.

[Thad E Ginathom]

Originally Posted by R2D2

Just keeping a container of dilute sulphuric acid shouldn't be too bad unless of course one touched the acid or if it were accidentally spilled. A capped container/bottle is a solution. But I would certainly not have one of these dangerous chemicals in my BR since there would be the small issue of my wife wanting to scalp me.

It was about an inch or so of solution in the bottom of an old mug. An open old mug. Although I think I put something on top of it when it was not in use.

During my jewellery-hobby days, I had the wonderful luxury of a separate workshop in two of the places I lived. In others, it was bedroom-corner stuff. But, in retrospect, this horrifies me: in one of those houses, two young children used to have free access to my room (in fact they made great alarm clocks). It's not as if I wasn't always aware how dangerous that stuff is. They never touched my workbench. But they could have.

[R2D2]

Originally Posted by Thad E Ginathom

....two young children used to have free access to my room They never touched my workbench. But they could have.

Well, children with their innate curiosity are pretty unpredictable and can hurt themselves. I am glad something, let's call it providence, kept them away from that acid container.

Which is why I always advise keeping batteries and inverters far away from and out of the reach of children. In other words don't install them in living areas. It's not just the risk of acid burns but what's even worse is the possibility of an electric shock that could kill instantly.

[prithm]

Originally Posted by R2D2

He (@ prithm)
@prithm, for suggestions look at this range: Havells' Exhaust fans

Thank you R2D2. I understood that part. Now, how do I make sure that it runs only when Inverter runs ?

Or it should be made to run manually everyday for few minutes by my parents without fail.

[R2D2]

Originally Posted by prithm

Thank you R2D2. I understood that part. Now, how do I make sure that it runs only when Inverter runs ?Or it should be made to run manually everyday for few minutes by my parents without fail.

Assuming it'll be an AC exhaust fan, it can be switched on or off by connecting it to your power distribution box via a switch mounted **outside** the battery storage room/compartment. But this means it won't work when the mains power fails.

If you want it run in case when power fails connect it to the output of your inverter, again via a switch as mentioned above. But it'll obviously draw power (40-70 W depending on model) which in turn will have an impact on battery run-time. You can request your parents to turn the fan on or off as required.

But gasses are vented when batteries are charged, not discharged. So the fan should be switched on when the mains power is restored and the inverter begins to charge the battery bank. Depending on the duration of the power failure and depth of discharge of the battery bank the charging process can take several hours to even a couple of days for large batteries.

[diyguy]

Originally Posted by prithm

Or it should be made to run manually everyday for few minutes by my parents without fail.

You can look at timer Programmable switches and you can schedule this to run at specific times and switch off again at specific times. Multiple such schedules will help you cover the entire day if you desire. Google sonoff. I use such a device for my outdoor night lights.

[R2D2]

Originally Posted by diyguy

You can look at timer Programmable switches and you can schedule this to run at specific times and switch off again at specific times. Multiple such schedules will help you cover the entire day if you desire. Google sonoff. I use such a device for my outdoor night lights.

The fan has to run when the inverter is charging the batteries (or even 24 x 7) & not by a timed schedule which will be of limited use in this particular use case. For a small compartment with 4 large tubular batteries I would suggest mostly continuous exhaust fan operation since hydrogen gas concentration can increase over the danger threshold (about 4-5%) very easily.

My inverter and 2 x 200 AH batteries are located in a small room of about 4 x 9 ft x 7 (h) & the the sulphurous smell of those batteries can be very noticeable. We leave the room door and window open for a while if the battery has been charging for a long time to let any gases escape from the room. The idea is not to let the gas concentration increase to a level where there is a risk of an explosion.

[prithm]

Originally Posted by diyguy

You can look at timer Programmable switches and you can schedule this to run at specific times and switch off again at specific times. Multiple such schedules will help you cover the entire day if you desire. Google sonoff. I use such a device for my outdoor night lights.

Sounds interesting. Will check. Thanks diyguy.

Originally Posted by R2D2

The idea is not to let the gas concentration increase to a level where there is a risk of an explosion.

Just pondering, are people who store their tall tubulars in trolleys (like Luminous etc.) which is totally enclosed by the manufacturer (no vents anywhere) running such high risk ?

I will try to get those brushless fans as you suggested R2D2, but I am equally inclined to give some gap in the metal door to let the gas escape from the top. Since Hydrogen is less dense and rises up, it will have an opportunity to escape along with any draft from outside.

Having gaps at the lower end will jeopardize security against critters and crawlies in my location.

[R2D2]

Originally Posted by prithm

Just pondering, are people who store their tall tubulars in trolleys (like Luminous etc.) which is totally enclosed by the manufacturer (no vents anywhere) running such high risk ?

There is only 1 battery/trolley IIRC because putting in two batteries which weight about 100-110 kgs may overload those plastic wheels. 1 battery inside a trolley doesn't pose a problem but if you have 4 venting gas during the charging phase in an enclosed space then it does.

I will try to get those brushless fans as you suggested R2D2, but I am equally inclined to give some gap in the metal door to let the gas escape from the top. Since Hydrogen is less dense and rises up, it will have an opportunity to escape along with any draft from outside. Having gaps at the lower end will jeopardize security against critters and crawlies in my location.

For air to flow out through the exhaust (active/passive) there has to be an inlet too. No room is airtight so a fan will work without any gaps in the doors. Or you can have a metal door with a mesh grill on the top. This keeps away the creepy crawlies and other pests. The advantage of having a fan is it obviously drives out more air by volume than a passive solution and guarantees air circulation.

There are many ways to get to the same objective i.e preventing gas concentration in enclosed spaces. Which method you use is your call.

[Aroy]

Originally Posted by Thad E Ginathom

Gentlemen, if a fan is installed near the batteries, it's it free from spark risks?

Yes if it the type used in mines or other flame prone areas.

In general most AC fans are brushless and only areas that can spark are wire termination. Solder the wires instead of twisting them and then cover them with Tape or Shrink Wrap material. If the batteries are between the fan and outlet, then the air current will blow the hydrogen away from the fan reducing chances of fire.