DIY Solar Hand Truck 2724LV-MR

[BuffaloTrace]

Been using and testing the for at least 6 months. Bought everything over a year ago, but took awhile to get everything put together in what little spare time i i have. While far from perfect, so far I am pretty happy with the simplicity and ease of build

Aside from all of the "custom" work it's basically made from stuff I had lying around the shop.

1. 8 x 100ah CALB cells (Docan)

2. Overkill Solar 100a BMS

3. 150a ANL Fuse

4. Mppsolar 2724LV-MR

I will post some more details on specifics if needed.

 

[BuffaloTrace]

The cells I received from Docan just over a year ago were in good shape on arrival, there is or was an unboxing vid I posted awhile back.

The inverter came from Ian at watts247.

Everything else was amazon. So all in all the new parts were easy to source. This small simple system is basically running my shed, and when the power goes out I use it for back up on anything I need. I do have a couple other small charge controllers I will add to get more. Currently using 440watts of panels on shed roof. Things get done slowly here.

 

[dsmith1279]

Morning! I'm new to the group and am looking at doing the exact same build but with 2 12v 200ah Ampere Time LifePo4 batteries and 4 100W (2 in Series and then Parallel) panels. Hows the system working out for you? I'm doing it as a full grid down back up for my full size freezer and fridge.

 

[BuffaloTrace]

I've used it for a bunch of stuff now, including refrigerator and freezer. I currently have only a small 440 watt array on top of my shed, but so far the 2.4kwh of battery has easily carried me through the outtages as we use very little power as it is. The small array will get the power back up to full between uses but slowly, especially with this winter weather.

I've also used this 2700w inverter with many tools including a craftsman 14" bar electric chainsaw and a small 5ton electric log splitter. It's managed my offsite firewood harvesting with ease. So far it was a nice worthwhile fun project. Always cool to have this thing ready for mobile power, which has been its primary use so far.

 

[BuffaloTrace]

A couple small arrays on the shed.
Roof mount are used 220w, 52voc panels, but most I've measured is just over 50voc on a cold morning, and cold being mild for most as its near california coast.
These 2 panels in parallel are perfect for the Solar hand truck mppt on the LV2724.

The small window shade array are series connected 30w panels for a small 10a epever tracer older BN series scc. Cool thing is the 150voc input. This little array is for a small 12v lifepo4 for 12v accessories, interior shed and carport exterior lighting (12v).

Panels are all facing due SW at a slight angle so I'll get a good midday and afternoon sunshine as it can actually be foggy sometimes in the morning, usually burned off by 9 or 10am.

 

[Motormouth]

I love your cart!! Beautifully done. Are you worried about the wood getting to hot?

 

[BuffaloTrace]

I love your cart!! Beautifully done. Are you worried about the wood getting to hot?

The wiring is all oversized, and while I wasn't worried about the actual cells overheating, i have seen poor connections to batteries get extremely hot under load.
All bus bars were torqued to spec and cells are in a "compression" fixture by design a near perfect fit side to side, and easily slid into the box at around 50% charge. There are rubber covered square bars that run on top the outside length of the cells, easily clearing the terminal posts, and hold them down in place so as not to be able to slide up and down either. The square bars are held in place with all thread running length of the battery that doubles as carrying handles.
My main worry was actually the 8s heltec balancer is just double back taped ysing mounting tape to the top of one of the cells, but is held down pretty well by the "lid". I should post some pics of the battery build.

 

[Motormouth]

If you are willing, I would like to see your battery build.

 

[BuffaloTrace]

Sure thing, as soon as I can find or dig them up from last memory card from phone. Built battery over a year ago.
I will be disassembling and checking cell health after the month of winter solstice when I get the data from solar production from the 440w on shed roof.