Elon Musk is targeting $50. a KWH for batteries. I have gotten enough for me to hold out till the price drops to that level. The new batteries are soooo much better than the old ones.
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For now I like the simplicity of lead batteries for powering the shop. I am a simpleton and lead is really uncomplicated and local. I have to admit that I am a bit old fashion, after all I use producer gas. Lead is also a battery that I could build myself. Plus I have a number of machines that use the same size battery
I can see a portable litium battery in my future. That would be just the ticket to power my 12v air compressor. Plus other stuff. Not to mention all the other small application that they are perfect for.
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My theory is to build with the cheapest solution today which looks to be the used medical batteries from battery hookup. In 5 years time they will mostly need to be replaced but I will have the electic tractor to use until they do and I will just need batteries. My guess is as millions of people start crashing their new EV vs their new ICE cars we will see more and more cheap lightly used batteries also as the world gets more capacity to manufacture the cost will definitely drop. But I canât see waiting 5 to 10 years to start the project I want to build.
If I was looking at home solar I would definitely use a thermal mass for expanding the storage it is still the cheapest solution to get the most energy value for your investment.
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Hi Dan, what application will you use your tractor for? Sounds interesting.
I have a couple of case ingersoll garden tractors I want to build something like this.
That one was made by someone in Massachusetts years ago if you Google case ingersoll 4x4 pickup you can find their story on the case ingersoll forum.
I use the garden tractor I have with a 10 hp diesel engine all the time to rototiller my garden split wood and rake my hay. I am raking with the pasquali this year as it is just enough faster that I can get done and move the backswath bales before my uncle finishes baling. But the electric motor should give me just enough higher speed to solve that problem. I like the case ingersoll 448 tractors because they are larger tires for rough ground and portable hydraulics. There is just a hydraulic pump on the motor and a hydraulic valve and hydraulic gear motor in the rear axle. Building a small 4wd with a platform on it has been a dream project for years. The idea of electric would also be to move hay for my cows they need 10 bales a day and other odd jobs around my farm I find myself starting my diesel pickup for and shutting it right back off.
I want portable batteries the 50 cal ammo cans will allow that because they will be about 25lbs each with a plug because my second project is something like my old farmall H that I can do some of my field work with. I am still thinking I might find a different donor tractor as the H has a narrow front end and doesnât have live power. I am pretty sure I could find a better donor cheap enough. But ultimately I would love to get all or most of my farm work done without ff and I dont want a gasifer in a hay field.
20kwh will run that case ingersoll for 5 hours. I believe I can use a 4kw electric motor to run the 12gpm pump.
I can see myself setting up a gasifer to power a stationary generator after I get the solar system installed though.
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Dan, that is the sweetest tractor in history. I hope you keep us posted on the electric version. Thanks for the update! I love stuff like that.
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+1, I almost bought a similar one before I found mine. Keep us posted!
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there was a large lithium battery fire out here . The way to control fire is to entomb the batteries in Portland cement .
Also Thursday, Morris Fire Chief Tracey Steffes said that the fire department Wednesday night applied 28 tons of Portland cement in an attempt to âsmotherâ and âconsumeâ the batteries, which had reacted to the heat.
âThat Portland cement has worked,â Steffes said during an early afternoon news conference. âWe made a lot of progress on-site, so this is good news.â
But the fire, which began on Tuesday, was still burning Thursday.
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Something off about those numbers. 28 K of cement would be a volume of less than 10 cu yrds. If they were talking about concrete then it would be about 80 cubic yrds of a very weak mix. Seems like 200,000 tons of batteries would be a much larger chunk of real estate than you could cover. Donât quote me because I suck at math.
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The fire fighters first used 1000 pounds of purple k to no effect , Then used 28 tons Dry ? portland cement .
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I was looking on Permies.com and saw that Ben Peterson has a E-book on Solar Station Construction Plans if anyone is interested.
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Need some help. What is the difference in a charge controller(pwm) for lead acid, and one for lithium. I already have the first one(black) is it the same as the second one? https://www.ebay.com/itm/265208372043?var=565081939085 10A/20A/30A PWM Solar Charge Controller 12V 24V Auto Battery Regulator Dual USB | eBay
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The difference is that the second one appears to have a charging mode for either 11.1v or 12.8v lithium batteries in addition to the usual lead acid charge profile. Lead uses a 3-stage charging bulk-absorb-float that involves raising the voltage well over the nominal rated voltage of the pack. Lithium does not like that, and so you need to do a 2 stage constant-current/ constant-voltage charge cycle.
In my opinion, if you are trying to charge expensive lithium batteries, you should get a controller that lets you program exactly which values you want. If you are just charging lead, then either one will work fine.
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I have lithium batteries, and I use both an Outback FM 80, and an Outback 60 charge controllers, As Carl says, you want to use a charge controller that will let you change the charge top off point. If you over charge a lithium battery you are looking at a visit from the fire department, Not a good thing. Also to note if you charge most lithium batteries when it is at freezing you can also destroy the batteries. A good BMS ( Battery Management System ) will allow you to shut off the charging when it is too cold for the batteries to be charged. I have been using the check makeskyblue charge controllers with success, but I follow their directions exactly I have all the fuses they recommend. When you get the system working it is awesome, I went off grid a couple weeks ago, and I love it 
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Al, I have one of the first style, but have not deployed it yet. I have been buying these since 2012. Usually, the failure mode is to open the solar panel circuit. I did have one that failed by allowing over voltage, or NOT opening the solar panel circuit. Based on this, I would not use these on anything bigger then a 100 watt panel with an open circuit voltage of 20vdc. I would use it on a system whose battery side is much bigger than the solar side. That way itâs either on or off, not transitioning in that saturation zone that MOSFETs hate.
I would camp right out on this type of controller, (with a DVOM) and make sure you get the voltage cut out set right, especially if you try it with lithium. The learning curve with the YouTube/chinglisch instructions is a pita.
I am using this for a led dusk to dawn light. I bought several lights, and they donât last. If lithium is that sensitive to cold weather how do they hold up in outside lights? or is that what goes? The ones I have taken apart, the batteries are still good.
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Lifepo4 suffers failure if it is charged when the cell is too cold it will damage the cells. I donât know for sure if Lithium ion has the same failure or not. I havenât seen anything definitive about what happens when you try to charge a lithium ion when it is cold because everyone is far more worried about them overheating when over charged.
I would guess most of the lights you have seen are lithium ion batteries it is far more common than the longer life lifepo4 at this point.
LTO cells are not damaged regardless of how cold they are when you charge them the chemistry just isnât subject to that type if issue. But they are very expensive up front even though they last for 30 000 cycles. Which is crazy long.
But I believe all 3 types of lithium batteries can be discharged in the cold without any issues it is only the charging which can damage the cells.
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I did a little reading about cold charging lithium batteries, and what it sounds like is that not charging below freezing is more of a good rule of thumb than a hard limit. It sounds like as the temperature drops, so should the charging current. Really, most lithium ion chemistries dont want to be charged at full power below 10 Celcius, so it seems likely that you could probably get away with a very slow charge at lower temps, and somewhere around the freezing point of water, that charge current gets low enough as to be impractical.
As for checking out the cells in your lights, did you do a measured load test, or just check the voltage? A cell that has plated out a bunch of its lithium would probably still measure full voltage, but if the capacity was drained, it would quickly stop working once you tried to make it do any work.
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We had a light like that my dad sent us. It was a dusk to dawn. The circuitry that charged the battery from the solar panel went bad.
We added a length of telephone wire from our main 12vdc bus, to the light. Then we added a 12v to 5vdc adjustable buck converter to the light. We dialed it in for 3.9vdc and have been happy ever since.
This might be what has failed in your lights.
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