Questions on off grid systems

Billy, I get it.
As with any shtf-scenario we have to try imagine (guess) what will be available. I’m with TomH here - we will more likely be able to still get our hands on lead acid batteries. Any redneck solution, far from perfect, will have to do.
What we already have is the most available. I recall Jakob wrote you have 7?, 9? vehicles? See to they all have 12V outlets in the front - make an octopus connection and make sure you always plug in when you park. That’s your battery bank. 9 X 80Ah = 720Ah = 8.6 kWh. If you can utilize half of that, that’s still pretty good.
The octopus can be constantly fed by a couple cheap 12V panels if you want. A downside to having all the batteries in parallell is they all have to be in pretty good shape or a bad one will affect others.

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I am no expert BUT i have lugged around more batteries than i care to recall , i have a friend who owns a scrap yard and many years ago i bought 8 large L16 trojan batteries off him when they gave up the ghost i took them back and replaced them with a load more deep cycle batteries then more and more and well you get the idea so i have been very lucky being able to replace them all for free for years , now older weaker and of course unable to throw these cells around ( living on a very steep block of land with no way of moving them around , i have been lucky enough to lay my hands of 8 lifepo4 110 AH batteries and they have changed my whole way of making and storing power for me or anyone else similar to me i would say 100% go lifepo4 invest the money and never look back , after all you have some great retailers in the USA selling second hand or new new cells for what us in other country’s can only dream of .
Failing that then i have seen your set up Billy and i would start looking for old forklift batteries they are cheap and you have the machinery to be able to move them around and transport them , they are very forgiving if misused they can be revitalized and repaired unlike VRLA batteries glass mat or gell once you go below 40% depth of discharge they will never come back to the same power as before i have found from all the ones i brought home .
If you don’t like solar panels then your gonna have to use a charcoal driven charger to keep them topped up for when needed .
Dave

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NiFe cells have very poor efficiency, like 70%, and low power output. they want to run long and slow. Great for off grid until you need to handle the surge current on a well pump.

Lead acid is potentially user serviceable, yes. It is a well understood, simple technology. You would be remelting plates on some frequency. The sulphuric electrolyte is possible to produce in a makeshift lab but it is not easy, especially if you plan to avoid using any store bought consumables like peroxide. The standard process to turn raw sulphur into sulphuric acid requires some exotic catalysts. They aren’t consumed but might need to be refreshed now and again. Realistically a person would need a good bit of training and practice to pull it off. It would be more practical to have a lifetime supply on hand. H2SO4 is cheap as can be.

No one has brought up Lithium Ion Titanate (LTO) batteries and you really should have a look. They are expensive compared to LiFePo and other more common Lithium types and slightly less efficient. But they last 5k to 10k+ cycles and are more or less indestructible. Cycled daily those cells would likely out live their operator.

If the forever battery nature of NiFe is appealing, check out LTO. Some manufacturers focus on high cycle life and that would get you pretty close to forever (20k cycles). Honestly if the grid is down for 20 years I doubt many of us reach old age anyway.

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Your point is well made Anthony. First rule of prepping is, If you can’t make it, make sure to store it. Acid is a case in point, however in the true SHTF situation there will be many abandoned vehicles with batteries full of acid as well. Still better to have a stored, assured supply.

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here is a discussion on making your own batteries, Making large PLANTE lead acid Batteries. (fieldlines.com)
kent

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thumbs up to everyone.

JO…yes. redneck I can do. It just sort of oozes out of me like some kind of aura.
That was Part of my question … how many lead acid car batts in series would I need to run a freezer, couple lights and a fan or 4? How much does a fridge add?
That helps.

I currently do the same in the fuel shed. We hgave a small harbor freight solar panel and charge controller hooked to a stack of car batts I have pulled out of customer cars that only test 8-10 volts. They seem to stay charged plenty to run our fuel pumps.

D&B: I used to do the same when we hauled batteries to the recycle plant for the local recycler… There would always be pallets of good…even new…batts of all kinds. we would just swap them weight for weight for what we were hauling half a dozen at a time. Not as much available now a days though.

Also, used to get good batteries from the Army depot at Ft. McClellon. Don’t get them in there as much since the wars have ended…

I think the fork lift battery idea is doable.

A…: Plenty of acid around here. Whenever we send in a batt for a core we drain it into a bucket and keep it around. Also, I think I have a lifetime supply of new around here as well.

Just have to make it through the first decade or so…

Probably…though I probably have enough acid in batts around here for that…But as for functional batteries, I think they will be one of the few parts of vehicles that will not be readily available because people will use them…misuse them…for lighting, charging stuff etc…

On the other hand, tires, wires, and transmissions will be quite cheaply bartered for…assuming there is no fuel to fire the machine.

I don’t particularly mind some solar panels. I just don’t like the endless fields of them covering up all the farm land.

I will check into this…thankyou.

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I can’t find any consumer available LTO batteries in the US. Just off of Alibaba/China sellers. I would like to get some, maybe 300amp hours worth over time but when it comes from halfway around the world you really have to order in bulk to make it worth it. Waiting months at a time for delivery etc.

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Just a quicky about the electrolyte in old batteries , unless a battery is fully charged you will find that what you are pouring out of a old battery is almost water ,it will be so weak its useless the acid in a battery never goes away its always in there unless the battery was tipped over when it was fully charged , in other words you can only get the correct % of water/acid mix out of a fully charged battery , test it out and see grab a very old flat battery and drop some of the electrolyte onto the floor and see it fizz or not as the case may be and then do the same with a fully charged battery .
don’t bother adding sulphuric acid to old cells as you will kill them real fast with over strength electrolyte
Dave

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Yup yup. I pulse them with maybe a minute of overvolting with my stick welder and then leave it on a respective charger after letting it rest for 20 minutes. I have an old 6-12v inverter charger that actually varies the amount of current depending on the battery’s charging progress. Works awesome. I only do this with flooded cells, it would probably fry an AGM or gel battery even if water was added to the Gel, the plates are just too close together.

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That is valuable information I was not aware of Dave. Obviously some research needs to me done. Thanks.

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Probably different in your area Billy. Around here I doubt that are many people that even know what a car battery does. Since gas stations don’t have air pumps any longer they have to go to a garage to get their tires pumped up.

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It’s hit or miss for compressed air at a service station around here. Costs money to use most of the time.

I found in my county the very last full service gas station. They checked my oil, tire pressure, and gassed me up. They just enjoy doing it, breaks the monotony of sitting behind a counter all day.

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30 years ago if you told me you would have to pay for air and people would buy bottles of water I would have said you nuts…

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In Arizona water has to be offered for free. They put in a law for it because it gets so hot there it’d be a death sentence to deny someone water. Had a buddy that lived there for a few years.

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Up here there was a situation in the 90s where gov inspectors were cut back and the water supply in a town called Walkerton was contaminated with E-coli.

Before this happened I was living with the wife in another town a short drive away.
The wife did not want to drink the water from the tap.
I did ( ya it did smell funny )…

It was inconceivable to me that water from a tap could be tainted such was my faith in Ministries involved in water quality regulation.

Anyhow that was the best advertising Coke and Pepsi ever had to get people to buy water.
I still drink from the tap…
The gov back tracked on a lot of the cuts and restored the inspectors.
And to this Day tap water is still more highly regulated than bottled.

One has to question how did end up in a situation where people put a price on air and water and we think its reasonable to pony up a dollar for it.

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Hi Tom if you have spare time and want to listen to a English man going on about how he manages to keep his forklift batteries alive for many years , then sit back and have a smile and a giggle and pick up a few tricks , he has many video’s on these types of cells .
Dave

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How often fellows have I brought up these electric vehicle range extenders?

This is an Indigenous Chinese product design that I think is BRILLIANT.
Designed to automatically start and stop as batteries required to keep them from completely discharging your batteries and damaging them.
https://www.dhgate.com/product/black-is-more-cool-using-a-new-frequency/407445439.html
No matter what you have for a system you need something to provide supplemental power on demand automatically or you need to manually do these things.
For a lead acid systems I would set something up so it comes on if the batteries are at 60%.
Shut down?
Depends on load and your renewable generation capacity.
The best of these from China right now can be programed with those parameters because this is a universal range extender designed for this kind of electric vehicle running lead acid batteries.

The smart way to charge these things is by plugging in.
The range extenders are there to fire up and protect the batteries so you can get them home for a proper charge.


Last summer I was sent to this level and service these battery electrics because the company ( that shall remain anonymous ) did not have properly trained people to care for these old girls.
I want you to look at the cables and bunks on the sides.
How this is supposed to work is once the tram crew sees they have used their battery to about 50% of its rating or at the end of the shift they are supposed to lift the pack off and swap in a fresh one for the next shift…

Batteries are to be inspected and watered monthly.
The chargers are to run a complete charge cycle on on each pack to carefully bring them up to a full charge.
Monthly inspection is watering cleaning check for damage or wear ( controls on trains too )
Brush replacement if needed and reports and records kept to track costs and watch for issues.

When I got there this had completely gone to hell.
Dead trains sitting in the middle of the track with no power…
Batteries that were sulphated or worse dry or frighteningly so neglected they smoked when you tried to charge them
Trains with electrical issues that had caused fires ( and the ministry asking for a report on the fires and what was to be done to prevent this ).

I did not solve these issues but I did help a little to get them back on target.

My point is you have to keep records and logs and watch for trends that tell you you have a problem.
You need to do monthly service.
And you need to do daily care and up keep.

Battery systems need constant care and attention or they will fail.
They quiet simplicity will lull you into a false sense of all is well until its not, and that can cost a lot money and cause fires.

Think about your system and what it needs daily, weekly and monthly.
Make a plan to ensure all parts of the system get the attention they need.

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I’m seeing LTO cells made available to US consumers through audio electronics retailers.

Walmart.com makes these available on their website from a 3rd party seller:

https://www.walmart.com/ip/XS-Power-66160-2-3V-40-Amp-Hours-Lithium-Titanate-Oxide-LTO-Battery-Cell/448265771?wmlspartner=wlpa&selectedSellerId=17831

~$1 per watt*hour isn’t cheap but again - these cells have some special features. Most of the listings are Alibaba/bangood/etc - IE Chinese sourced. The walmart link above shows cells with Chinese characters so really just an importer/reseller. I see one specialty seller in the US as well but it looks like it may be the same brand of cells and a related entity to the Walmart seller.

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