Daniel Schmidt

Since my post got wrecked by my phone, the short version is SendCutSend, PCBWay and other places online (no first hand experience) cut and in some cases fabricate boxes and other things from the various materials they offer.

It's probably a good idea to use bulkhead fittings to pass the wires through and mount the BMS on the outside vs try to cram things in with the cells and risk an accidental short. You want the cells to stay together and not flop back and forth while driving, so keeping it somewhat tight and padding the remaining free space will stop that from happening.

Thanks for updating this thread. I will probably start a new one with some of my other solar and battery experiences, but I've learned a lot more about power tool battery packs since my last post here.

I had a quote but my phone keeps breaking my posts.

This is something I learned more recently that can be different on different tools, even from the same manufacturer. The charger for most tools seem to do all of the BMS duties similar to an RC car battery system. Which means many tools like the old Makita drill I came upon has no BMS in the battery pack and no way of shutting down the power when voltage gets too low. This seems needlessly dangerous.

What's worse is the chargers tend to have a very aggressive charging regimen of full current, half current near the top, then done. No constant voltage with variable current at the top of charging. Without that, there is excess heat produced shortening the life of the pack. Power tool vendors have largely become battery pushers. An interesting contrast I found is people replacing the cell inside wireless PlayStation controllers. They step the current down in stages starting around 3.9V and seem to take other factors in to account so it might not charge the same way twice. They aren't in the business of selling cells.

The knockoff SkyRC B6 chargers I got off of Amazon have been absolutely amazing for the price. They not only do constant voltage at the top of charging, but they charge 1S through 6S packs, settings for Li-Ion, LiPo, LiFePo, as well as NiCad, NiMH, and lead acid of various cell configurations. I've gotten a lot of people back on the road from a dead battery with them. Since they take 11V - 18V input, they can easily be used with a car battery or 4S Lithium battery to trickle charge a car or charge a tool battery in a less damaging way than the expensive charger the tool came with.

I've been putting a lot of these thoughts in to text form recently and need to get it all organized. I have had a great experience with my solar boost converters charging my ebike batteries. I've found most cheap solar chargers that say they do 12V 'lithium' are LiFePo only, or need extra stuff and an 'app' to do custom profiles. Maybe when I sell my property I can invest in the open source hardware solar charge controller I ran across a while back. Right now I can't invest that much money or time in to something that may take me months to get working properly.

I've just been using solar to directly charge my ebike, or charge an old car battery to then charge a bunch of more portable 4S3P packs, which can then charge anything the B6 chargers mentioned above can do, or the USB-PD car charger for my phone and laptop. My phone is tethered to one right now! It's handy to grab a 4S pack or two and the chargers and head out in the world on solar power.

To be completely honest I just slot pennies in to the battery connector slots for my power tool batteries and hook my alligator clips to them. At some point I should add balance leads to the packs, since the B6 chargers can also balance up to 6S packs. On the Makita drill pack I opened it up and charged the parallel cells separately from the ones in series. As long as you get it balanced before putting back to use it works great for salvaging cells. It's the same way I built many of my ebike batteries.

With my body not getting any younger and being unwilling to ever drive a car again, I'm going to have to abandon the idea of making my land legally inhabitable. For someone willing to drive it might be worthwhile. The unique part of the property relative to most others in Florida is there is about 30 feet of elevation from the lowest point near the road at the NE corner to the top of the hill along the southern boundary. The property is a bit shy of 150 ft wide by 300 ft deep South of the road to the back of the property.

It's kind of a small valley where you drive over a hill, get to the bottom and that's where the property line starts. With no shortage of rain water, it can be collected and moved downhill via gravity. I've done similar to run drip irrigation at my old house and it worked really well with only 5 feet of head pressure.

In 2019 I had tried building piers and building a shed, and the next time I made my way down there had been some vandalism. Someone actually spray painted "pass gas" on a stepping stone haha. They pulled the piers out of the ground and carried one of them all the way to the corner of the property by the road. Who knows if the adolescent vandals are still there, but I do not have the wherewithal to deal with the daily sabotage I currently live with, let alone trying to fight against vandals that live much closer than I do. I get the impression anyone doing anything besides clearing the land and plopping a house or mobile home on it will be looked down on and possibly have an uphill battle. Just being honest here as to why I'm giving up.

In any event, I'm probably going to dig thru all of my mail and contact some of the people who have made cash offers and take the best one. Last time I checked it was over $12k, so $12,000 firm is my price. This isn't going to happen overnight, but I have all intentions of getting the tax paid and then selling the land by mid spring at the latest. I will try to give this thread at least a few weeks time on the offhand chance someone here is interested. None of the other properties around me seem to have sold or been cleared since I got my acre, so someone could buy up a few plots and own the entire little valley. I had lots of 'friends' that were 'interested' but never put their cash down like I did.

I really like growing things here in Florida, but I have nothing else keeping me here and with no viable way to make my land work for me I must abandon it.

I've been down this road a couple of times. It's a pain when one of the front burners becomes unreliable. I ended up switching the knob/thermostat with one of the back burners until the new one came in. Part of it was not wanting to reach to cook and part was other people forgetting and burning their food.

I haven't found many seeds, usually after things had dried up quite a bit. As you can see with the flower clusters, you can easily have a dozen or more flowers per foot of vine. I'd imagine this takes energy away from doing other things, so I don't know if pinching a bunch of them off will help with seed production. Each flower doesn't last too long, so if you did get any it would probably happen in the next couple of weeks.

Those are clusters of flowers. They grow much the same as the leaves and roots from the nodes. When I first started I went through the same with a few here and there, then clusters all over one fall. I didn't get any seeds at the time. They are oddly shaped little dark seeds. If you get any they will be after the flowers bloom. It's nice to get outside early and see all the activity around the flowers before the sun starts to beat down on them.

What brand battery are you using? LiFePo batteries have some sort of battery management system (BMS) inside, and different BMS's operate differently.

thomas rubino wrote:Although not cheap, the heat fans that sit on your wood stove produce a significant breeze, using no electricity at all.

 

They have a Thermo Electric Generator (TEG) inside them powered by the heat of the stove. Technically you could rig something up to power them with heat for cooling purposes, but with that much cost it would be cheaper to add more capacity/production to whatever off-grid energy source is being used.

I don't know how useful this idea would be for a multitude of reasons, there is a really good video about more efficient ceiling fans here:


If you already have a decent plan for powering a ceiling fan then finding a BLDC fan is a good option. It's possible to find out the specs of the motor and get a different motor controller that hooks up directly to DC power, but that's pretty technical and probably not worth it if you are only running on a 12V or 24V battery system.

I have taken a bunch of used PC fans and hooked them up in various ways to provide cooling. If you have appropriately sides hole saws, you can mount them to a piece of wood and make a duct to move cool air in or hot air out. I had my bedroom set up this way for several years. Especially when using old fans, they sometimes make annoying resonant sounds at certain speeds. Rather than buying individual speed controllers, I just found a voltage that they would run at without being too loud (such as 9V) and powered them with that. Since they were free, I could use a few extra to make up for the loss of airflow by undervolting them. They are already long lived, and running them slow prolongs that life further. Keep them clean and they can run non-stop for several years.

I was also using this for drying clothes. The rain is pretty much daily and sporadic around here, so just leaving a line out in the sun can be problematic. I had a free sheet of steel roofing that I covered a small rack inside a plywood box and used one of those USB power banks to run 4 smaller fans at 5V to exhaust the moisture laden air. I only used what I had on hand just to see if it worked. Nowadays you can find USB-C power banks that are capable of giving multiple voltages, such as 5V, 9V, and 12V which could be used to power a number of fans. You would have to figure out the current draw of the fans and the rated output of the power bank. They make various adapters (trigger boards and cables) to get a consistent output since USB-C needs to communicate with something to output the correct voltage.

You could also use any type of battery with an appropriate buck/boost converter to give what you need. The benefit to this is you can have a small number of quiet fans closer to you and perhaps a few more fans elsewhere for intake and exhaust. I had some small wires going around my bedroom for fans and lighting, but it would be easy to use separate batteries. Of course this is from the viewpoint of someone that can make battery packs for dollars instead of hundreds of dollars.

All of the videos I am finding right now are people replacing the evaporator line with a new one. I don't see any replacing the condenser. The upright freezers are either frost free (fans blowing through mini 'radiators' for the evaporator and condenser) or they have an external condenser on the back. I did see one video with a chest freezer that had a condenser on the back, and judging by the accent they were an ocean away. I'm extremely hesitant to give any info regarding refrigeration and have someone take what I say as fact when I have no idea what hardware they might be working with. It's very easy to make a logical leap to thinking something 'should' work and cause a serious problem.

A quick google image search for 'chest freezer diagram' brings up a bunch of pics with diagrams for various layouts. I'm not in the business of selling the machines, so I wouldn't know one from another purely by model name or number to be able to tell someone across the internet how to go about such a project. I learned on old cars that had leaked out years before I got to them and replaced the entire system with new parts. Those cars used the same r134a that many freezers use, so functionally they are very similar. If someone is looking for info in general then vehicle AC repair videos can give a basic overview of how the systems operate, as well as common faults that can occur.

I see a few videos of people making functioning systems, but they do things I wouldn't want someone to copy. The basic idea is sound if you know enough not to repeat the mistakes. You could disconnect the lines from an evacuated system, add more interior insulation, install a new evaporator line around the inside in a similar fashion to the original and ultimately get better performance. The reality of doing this successfully with the right ($$$) tools is a completely different matter.

I think I lost the two that I made, but I had taken a branch and made around 1 1/2" diameter versions of the kind without the spring that were flat on top. If I needed to keep an important note or piece of mail easily visible so I wouldn't lose or forget it, I could stick it in one to hold it up on my desk. They were also great for bags of chips, pretzels, etc. They got misplaced when moving, but if I find them or make more I will have to take some pics.

I also needed some medium sized alligator clamps one night to replace rusted ones on a battery charger and had to get creative. I JB Weld'ed some 12 gauge wire to the ends of a pair of the spring type, bent in a shape that would clamp on to a battery terminal. I attached the battery charger wires to that so I could charge someone's battery after their alternator failed. I had seen in years past where someone did something kind of similar, using foil around each end and held an insulating spacer in the end tied to a string. If anything pulled the spacer out, it would complete the connection to a micro controller to turn on a light. If you have to work with what you've got, then having clothespins around is quite handy.