Home made batteries.

[xelasnave]

I am thinking of having a go at making my own battery...actually proper name is an "accumulater" but the same sort of thing you have in your car.
So I ask has anyone here made their own battery or accumulator.
My plan is lots of lead flashing seperated by fibre glass with epsom salt in solution for the electrolyte.
I believe storage is worked out by surface area of the lead so I wonder does any one know how to work out potential storage.
I notice Bunnings have lead flashing in 3 mtr x 30 cm and I am thinking of using that much for just on 2.3 volt cell...so 1.5mtr x30cm plate area for each of positive and negative...and make 6 of them...but I would lke to know if it will work and storage potential.
Alex

[Wavytone]

Epsom salts and lead alone do not a battery make.

A salt electrolyte requires alternating plates of two dissimilar metals well apart in the galvanic series (ie anodic potential) to function - copper or zinc often being the other.

What you suggest also sounds very messy, environmentally very unfriendly and potentially a safety hazard - wet cell batteries can overheat, boil or worse explode or start a fire and you don’t want to be anywhere near when that happens. Fire involving an aggressive electrolyte and electricity can get very nasty.

There is however a much easier, cheaper and safer solution - head to any auto electrical place and you can pick up old car batteries for nothing. These can be reconditioned with Epsom salts, well enough to do what you want.

[julianh72]

According to http://wiki.diyfaq.org.uk/index.php/Lead_acid_battery_construction a home-brew lead-acid battery can have a capacity of the order of 1 amp-hour per square inch of submerged anode and cathode.

You're going to have to source some 4-molar sulphuric acid (probably not available from your local Chemist Warehouse!), and make sure the whole assembly is rigid enough to not short out if bumped, made entirely of non-corrodible components, located in a secure facility which is well ventilated, and resistant to acid fumes and spray.

As for whether it's advisable (or legal) - I'll let you do your own research on that! If you don't know how to handle concentrated acid safely (and in particular, the hazards of adding water to concentrated acid) - don't even think about it!

(Personally, I'd feel much happier just buying commercial batteries - but where would we be if Volta and Faraday et al had never played with these things?!)

[Startrek]

Agreed
Your safety comes first
I use to install lead acid and nicad battery banks for central inverter emergency lighting systems in buildings back in the late 70’s and 80’s and it seems like a high risk idea. I’ve seen the aftermath of a single 5 volt cell explode in a battery room and it caused a real mess, lucky no one was in there at the time
Leave the battery business up to the engineers and the manufacturers in that industry
No disrespect or judgement intended
Cheers

[xelasnave]

Thanks very much for all the input.
I believe at this stage from my research that epsom salts which I think is magnesium sulphate ( I will check as I would have learnt that in high school) works well as an electrolyte...I will look into this aspect again as I have not considered the chemistry yet.
Explosions can occur from hydrogen and batteries need to be well ventilated.
The reason I am thinking about this is the high cost of large batteries.
I recently purchased 6 2volt batteries (little more than 2) to provide a 12 volt system of 1140 amp hours and that was about $4500.
I would like a greater capacity and so have started to look at what I could build.
So far the idea is...
6 containers ( each to house a 2 volt unit) the total providing 12 volts (approx but you should end up at about 13.5 colts for a 12 volt battery☺)...each container made of concrete formed around and holding plastic "boxes" or alternatively fibre glassed concrete boxes and painted with tar...they will be outside under cover and given the weight will never be moved.
Each "plate" to consist of 1.5 meters by 30 cm. of lead flashing folded to fit in the box...say 5 or 6 folds for each plate and fiber glass mat to seperate the folds... I have a few ideas how to form and attach a terminal to each plate ... this is not a problem...two such folded units fit in the box and these to be separated by a layer or two of pink bat (the stuff you place in the roof☺)...
Hopefully as I said epsom salts works as the electrolyte as I dont fancy buying or making sulphuric acid...
I dont think one needs dis similar metals as this is an accumulator ...as are most units commonly called batteries.

If the indicator of 1amp per square in applies (Which may be at 2 volt or 12 volts???) I can work out a range of expectation for storage.

Needless to say I will build a smaller proto type before going big...but for now I will do some calculations for the large model which although a wide range will give me a starting point.

Thanks again.
I had hoped that we had a member who may have built one.

I dont see any environmental concerns if using epsom salts and I think by venting each cell and placing the cells outdoors under cover will prevent any dangerous hydrogen build up.
Alex

[xelasnave]

As to storage..if 1amp per square inch. ..each plate would be 430 sq inch for one side....ie 430 amps if you worh on both sides of the plate which would seem reasonable...thats 860 amps approx...mmm need more lead.
But as to costing it seems at this stage a two third saving so more research is warranted☺
Alex

[xelasnave]

I miscalculated...each plate would be 4.5 ft x1 ft...maybe 1296 amps for what I have in mind...cost say $1500 which is less than $4500 for 1140 amps...but I really want double...
Alex

[glend]

Alex i could tell you a number of horror stories about guys who were badly burnt in telephone exchanges, working on lead acid battery banks. And that is an environment where isolation devices were everywhere, and emergency first aid systems were readily available to flush eyes and skin, and people were trained to deal with accidents. Please make safety your number one priority and honestly, is it worth it?
And a reminder that lead itself is highly toxic, and it builds up in your body and is not easy to remove.

[Ukastronomer]

Why ?

Is this not a pointless idea in the 21st Century and not very environmentally good

[xelasnave]

Wait if it applies to anode and cathode and both sides it is double...I hope the proto type works.
Alex

[xelasnave]

All I need to do is build one zay with two plates each 10 inch square to make the sums easy and do some tests.
Alex

[xelasnave]

You live in the city so probably dont realise there are places that are not connected to the electricity grid and therefore need to generate their own electricity...

So my research is far from pointless as the house at Tabulam is not on the electricity grid ($500,000 to connect to the grid maybe more) and so we use solar power to charge batteries...the batteries are 12 volts but you run the 12volts thru an inverter and get 240 volts to run everything...so I would suggest that my carbon footprint would be less than someone getting their electricity from a coal powered generating plant☺ and so my idea is really not environmentally unfriendly ..in fact the opposite..and there is a wind generator as well...but you need to store the electricity you generate from the Sun or the wind in batteries. ..I have one old set of 1200 amp hours and a new set (yet to be instaled) of 1140 amp hours...but I would like more storage capacity as the Sun does not shine all the time so the more storage the better.

Its not just a crazy idea in the context that battery storage reflects on simple things like how much tv you can watch or if you can run a fan on a hot day.

Alex

[xelasnave]

Hi Glen
Thanks for the cautions.

I have been doing off grid for over twenty years and know about the things that go wrong...up atTabby a lot of folk make the mistake of checking the water level with no protection...nasty and painful...when I was in hospital once up there a lady was brought in as the batteries bubbled as she looked and she copped it in both eyes..but she did not lose her sight fortunately.

A lot of folk do not realise batteries give off hydrogen which can be very explosive when mixed with air ad exposed to an ignition sourse....so batteries must be very well ventilated so the hydrogen does not build up.
Alex

[xelasnave]

Hi Martin.
I already manage quiet a few battery combinations but I am aware of what can go wrong and rather careful.
Alex

[skysurfer]

Never do that !
Rule 1 of chemistry labs: NEVER add water to concentrated H2SO4 !!!

And making your own battery involves chemistry knowledge, more than high school chemistry, requires safety equipment such as a face shield, chemical gloves and if not outdoors, a well-ventilated fune hood.

[Wavytone]

Alex you can collect used car/truck batteries from auto electricians for free - they would otherwise have to dispose of them so you're doing them a favour.

There is a simple process to recondition them using epsom salts, and these would work well enough for what you want to do for many years.

[xelasnave]

I found this amusing.
https://youtu.be/Vw7lLuy8-IU

Way more sophisticated than my plan..well actually not really☺.
Alex

[JA]

You could try some "good" used batteries which have been on standby/ups service, rather than deep cycle use. As an example, perhaps something such as these-

https://www.gumtree.com.au/s-ad/sydney-region/other-home-garden/deep-cycle-battery-solar/1175133546

Much easier and less than your build budget. I'm sure if you look around you could do even better price/capacity wise from similar sources

Best
JA

[xelasnave]

Thanks JA.
Still need six of them to make 12 volts...
I may check them out however.
Alex

[leon]

Alex you are playing a dangerous game mate.

Leon

[xelasnave]

Thanks for that advice.
I will start putting out feelers.
Alex

[leon]

Alex don't do this mate,

Leon

[xelasnave]

Leon the batteries are nothing to the rest of the mess I must negotiate☺.

I So how is it going down your way?



Alex

[mynameiscd]

Hi Alex,
$4500 for 10 years power is a pretty good deal.
The average city dweller spends this in 2 to 3 years.
Ever thought about 24 or 48volt? Its so more efficient because of voltage drop over distance and esp that panels are all 24volt except fot the expensive 12v RV type which are nearly double for no other reason that they're for the caravan market.
Anyway good luck with the experiment and be safe!!!!
I miss being off grid!!
Never had a black out for nearly 10 years and now on grid we get one every month or so.
Definitely going to turn this house to battery standby.
Cheers
Andy

[xelasnave]

Hi Andy
I would love to go for a higher voltage and I have costed it and could see $20,000 going to do it right.
My daughter has a gaming computer that can draw incredible power...I was expecting it to take 100 amps at 12 volts but fortunately it runs considerably lower, however it was thinking about her needs that caused me to look into 48volt.
So I bought a key start sinewave inverter (2 actually☺ the second when the first needed a minor repair) rated at 2kva and ran the computer on it...later I found it runs ok via the inverter from the batteries but limit that actuvity to when the Sun is out...☺.

I have 7 old 85 watt panels and 4 recently installed 300 watt panels and have recently been given another 8 panels which are around 200...not sure on that...but they have to be installed.

I now have 6 generators☺ ... the last from Aldi I could not resist only $200 for 2 kva.

I guess the real reason I am thinking about building a battery is it just would be a neat thing to do. ..I have been watching too many how to youtube videos☺
Alex

[mynameiscd]

Well keep on to it Alex, you might discover how to make cheep, reliable, power storage out of basic household junk and revolutionise the battery industry and become a multi millionaire.
What's the worst thing that could happen?....
Well other than that it should be an interesting project to work on.
Just a quick note on power storage off grid.
I read an article a while back about using a decent auto start genset in the system and the economics of petrol vs battery bank.
It's cheaper to hammer the batteries and have a smaller, cheaper system and replace more often and burn more petrol rather than an over powered battery system to get the full 10 to 12 years out of the batteries.
Just replace a smaller system every 5 it 6 years and burn fuel.
Cheers
Andy

[xelasnave]

I would love an auto start genny one that kicks in when the battery drops to a particular level mmmm maybe the genny count will go up☺.
You end up using a genny a fair bit actually it is amazing just how much cloud there is...you notice that with astronomy and harvesting solar power.

Alex

[xelasnave]

What surprises me is how much solar power you can get when there is little Sun..early morning when the Sun peeps over the horizon you can get 30 amps ...must look to see what you get under a full Moon...must be something.
Alex

[xelasnave]

Duplicated post deleted.

[julianh72]

Alex - the trouble with being an amateur astronomer with an off-grid solar power system is that your life must be truly miserable whenever it is cloudy!

I suggest that to make your mood swings less erratic, you should have a second hobby which is best done when it is cloudy and rainy - e.g. breeding ducks, or growing hydroponic lettuces (or other "vegetables")!

:cloudy:

To get the best out of your solar system - have you looked at mounting it on a steerable mast, so that it will track the sun from dawn until dusk?

I know a boutique winemaker who wanted to go off-grid (for the house and winery complete). When he built his fixed array (about 5 metres x 5 metres, from memory), he was able to supply 100% of his energy needs in summer, but wasn't generating enough to cover winter, or cloudy days. He built himself a 2-axis steerable mast which tracks the sun all year (basically an oversized Alt-Az mount) and mounted the array onto that, and now he is totally off-grid.

(He uses a bank of commercial batteries - he was a Chemical Engineer at an oil refinery by profession before he became a winemaker, and even he wasn't game to make his own lead-acid batteries!)

[xelasnave]

Hi Julian
I spend cloudy time fixing preparing adjusting astronomy stuff and re processing☺

Actually I have other hobbies...paintjing, drawing, 6 string guitar and three string slide guitar.
I am not in one place long enoigh to have a vegie garden these days..at Tabby two or three weeks and the Sydney two or three weeks.

I have looked onto a rotating system but oddly enough, although there is 100 acres, there is no room for a mast within reasonable distance from the house and I would not mount it on the house as it does get windy on top of the hill where the house is...
I was even going to set up one panel (an eighty five watt panel I now use to power my mount in Sydney) on an old mount (the one that is becoming THE BOJAN WIDEFIELD MOUNT) to do some tests ... but I am certainly convinced there is a benefit.
The set of panels yet to be installed I will set half up to face West and half East to catch more Sun without tracking. ..although not efficient I think there will be benefits.
As to the winemaker he was probably more interested in making wine☺...I must make a small proto type and see if it works.
The main problem I see at the moment (assuming the idea has merit) is how to suspend the plates from the top of the battery...they will weigh 10 kilos.
I have given that aspect a lot of thought and thete is no easy way to get around such a simple matter..but it is clear that the playes need to be suspended and not just held up on legs or mat.

Anyways ot still seems a neat project.

Alex

[julianh72]

He didn't put it on a mast - he made a frame which is mounted on a slew ring from an old excavator, which is mounted on the ground - minimal footings required, because there is plenty of weight in the excavator slew ring and the frame. I think he just filled some old 200-litre drums with concrete and stuck the posts into them.

A motor slews the whole array every few minutes, and a hydraulic cylinder (from the same old excavator) raises and lowers the altitude of the array, so it follows the sun through the day. He can't raise the panel to vertical (as would required for optimal efficiency at sunrise and sunset) - from memory, it can go from about 25 to 45 degrees altitude - but he can get good power all day because it can point east and west as required, and it can rise to a steeper angle than a static solar panel array.

All built using his basic welding / handyman skills, and calling in a few favours from his mates when he needed a bit of muscle power. (Wine-makers rarely have trouble getting a few friends over for assistance!) His background as an engineer helped with working out the algorithms and automatic control system to get the tracking system working.

Bear in mind that this array powers his house and the whole winery (including a very large insulated cool-room) - your needs would presumably be rather more modest.

[mynameiscd]

Years ago my mate in Adelaide built a tracker from a couple of car windscreen wiper motors, some light sensitive switch gear and a bits and pieces.
It was pretty primative but it worked most times but occasionally it didnt switch the solonoid that reset it back to East at night.
Due to the cost of pro tracking gear and the price of panels (about 0.50c per watt), its more cost effective to get more panels to make up for losses from early morning and late afternoon.
Plus a lot less to go wrong.
Cheers
Andy

[xelasnave]

Yes that is pretty much what I came up with.
The other thing one gets efficiency conscious but I find usually just go bigger and inefficient to a degree.
Even the panels I have in play now do more than enough in one day...on paper they can produce many times the daily requirement...and so again it comes down to storage...the house needs only about 250 amps per day ( without the gaming computer☺) so it would be nice to have storage of say an additional 1000 amps which gives you four days with no charging at all...but to draw that much you really should have, on my conservation approach, a 6000 amp hour battery...without looking it up thats probably $20 k or more...and then you think heck I can buy a lot of petrol for that☺.
My main problem these days is I cant do so many things that when fit you dont even think about...like I need an electrician to change a light bulb simply because I cant climb a ladder..or a plumber to change the tap washer..not cause I cant change it but I cant climb down to the supply tap to cut off the water...similarly I cant get on the roof to instal the new panels...and for a man who did everything himself its a set back...like the clutch on the car that has failed...once I would have done that job.

One just has to adjust and play the game with the new rules.

Alex