Daniel Schmidt

John Weiland wrote: When regarding just the cells themselves, can a single BMS be configured to control both series connected cells and parallel connected cells within one battery?

A BMS is sold by the number of series cells it can control, and an amperage output rating. They never know how many parallel cells there are (short of fancy high end ones that ask you to punch in numbers, they don't *know* otherwise) and have no way of controlling them. The post earlier talking about the BMS "knowing" the battery state of charge must be talking about a particular model with a coulomb counter and some sort of display or Bluetooth connection to give a percentage. Most cheap BMSs don't have any of that.

Because they don't know any better you can configure numerous packs In to one large logical pack. With high output cells it's common to use some sort of cell to cell fusing so one bad cell doesn't take the rest of the parallel string with it.

Part of the reason you tend to see overkill connects on battery builds is usually because people are trying to push their build to extremes. Your wiring only has to be as heavy as your largest load demands, and fusing appropriate for the wire. If you only used very light loads, the voltage drop is extremely low, and you won't end up with much difference even if you added a few cables 10x longer than needed. At that point the cost per length is a factor. A heavy enough load will cause more voltage drop and could cause more drift between cells if one or more of the connections convert energy in to heat. Then there is managing cell drift once it occurs.

I have the original battery to my e bike which I got cheap because the tide came in at the beach and messed things up. The cell configuration went down one side then up the other, with cells at the bottom (pack middle) corroded. I lopped off 3 sets of cells (6P) to convert it from 13S to 10S, used thicker wire to bridge the gap, and mostly use it on lower power draw stuff like my hedge clippers or DIY slow cooker. A lot can be done with creative thinking if your goals aren't too demanding.

Catie George wrote:


12) If required,  repeat steps 1-11, because you discover that things didn't dry soon enough  (especially if drying indoors) and things became musty smelling, so you need to rewash!

I had seen this in the past. When I started hand washing last year, I tried adding a tiny pinch of baking soda to the final rinse and it no longer got musty. It may be different depending on your water, and too much will make your clothes stiff. In my situation it made sense to use the radiant heat from the sun to dry clothes while avoiding getting rained on, and some days that would take a while. With the baking soda I never had to rewash.

I definitely noticed the machines are so wild these days with settings that don't necessarily function the way the manuals marketing describes. Plus sometimes not programmed well at all causing errors and generally not cleaning all that well. I feel like the old washing machine idea is flawed and maybe there are better solutions to the way it can be done.

I'm not sure why I didn't see it this way sooner, but that clothes press looks a bit like a board thickness planer. You could possibly buy a used one really cheap and use that as a base to build one if you can't afford a new one. A planer sled with clothes coming out would look really funny, but it could work!

I've cut up a log by hand in to thin boards before. I used a cheap Japanese backsaw, which is really thin and cuts on the back stroke. I took a bit off of one side and used a plane to make a nice finish surface and cut off the next piece, so that by the end I would have boards with only one rough sawn surface. This was with some highly figured cedar, so it cut very easily.

If the wood is much harder to cut then definitely take your time with it. Do one or two small planks and move on to something less monotonous. A thick western saw is going to be a lot more physically demanding to use. The first backsaw I got was a Marples I found at Home Depot, and I used it so much that I ended up replacing it with a Harbor Freight version. I just used it to cut pieces for a bike trailer. I find it more convenient for small cuts than a circular saw. It can also cut much wider planks than a typical circular saw. Plenty of times in the past at work I have cut slits on either side of a boards and went back down the middle with the backsaw.

The only problem is that they are crazy sharp. You may want to wear a glove if you have to hold pieces with your hand. I had the saw pop out of the cut once and barely caught my thumb, but it was enough to chip a sliver of bone off and cause a lot of issues. With the right wood, splitting would be easier work, but that would take a lot of skill as well.

Yes, the property is to the South in Putnam County off of route 17 just before Crescent City. There are some houses and double wide trailers in the neighborhood, but many lots are still empty. If I could put in a full size house with foundation then it would be great for me. 700 sq ft is more house than I need or can afford out of pocket, so I'm exploring other options.

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.