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Semi-Portable, 2400wh LiFePo4 generator box. Almost done!

A.Justice

Swears he didn't start that fire.
Joined
Sep 12, 2020
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Location
TN
I wanted to build a high output, portable, lithium battery for work and car-camping. I already had eight 100ah CALB Cells, and a plastic Plano box that they fit almost perfectly into. The project was more about condensing and putting my system into a portable box, I already had most of the components assembled, but they were mounted to a wall.

I don't know anything about woodworking, but was able to build a wooden frame to mount components and hold the batteries still. I decided not to add any external connectors or ports to keep the integrity of the box intact, and to keep it more water resistant (The box is waterproof from a straight down rain, holes in it would make it leak). I'm going to mount any interactive (with buttons) components to the wooden panel on top of the batteries (2nd picture). I was going to try and put an inverter inside as well, but the box is too small for the size I wanted. I may hook up an old smaller inverter so it has internal AC power as well, but my intention is to hook up a Giandel 2200w pure sine externally, to power lights, fans, computer, a smaller heater (1700w, intermittently), and most importantly, the blower I use at work (2800 watt surge, about 2000w running).

-Eight 100 ah CALB Cells
-Plano box from Home Depot
-Victron 100/40 MPPT
*Things below are not installed yet, waiting on bigger drill bits and a jigsaw to mount them on the cover board on top*
-Shunt and monitor
-XaioXang BMS
-Panel with cigarette lighter, USB ports, -voltmeter, and a switch for charging small things
-5/16 battery terminals with a 150 amp fuse (through the BMS, it's the same circuit as all of the accessories)
-1/2 inch terminals through 350 amp fuse (bypasses BMS, on its own circuit, but has its own low voltage disconnect and relay)
-Switches to shut off one or both terminals
- Small Barrel, MC4, and XC60/90 ports
-Small air intake fan
-00 gauge wire on the 1/2 inch terminals,and 10g elsewhere
-Govee bluetooth thermometer and hygrometer, with alarms for my phone

Any feedback (good or bad) is more than welcome!
 

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Looks good! I recently did something similar form-factor with 280Ah cells. Although it's pretty heavy to carry if I were to ever try to transport it anywhere. Yours looks more reasonable for putting into the trunk of an SUV!

Not that I am a good example to follow, because mine was super dense, but you may want the MPPT to have its heatsink fins vertically so hot air can rise "out" of them. Right now you have them horizontal. I recommend you rotate it 90 degrees or add a tiny computer fan near there.
 
Looks good! I recently did something similar form-factor with 280Ah cells. Although it's pretty heavy to carry if I were to ever try to transport it anywhere. Yours looks more reasonable for putting into the trunk of an SUV!

Not that I am a good example to follow, because mine was super dense, but you may want the MPPT to have its heatsink fins vertically so hot air can rise "out" of them. Right now you have them horizontal. I recommend you rotate it 90 degrees or add a tiny computer fan near there.
That looks really slick, I like the floating breaker panel.

I'll definitely turn the MPPT around and add a fan, I have a second thermostat (Amazon 2 pack!) that I use for my heating pads, and I might try to rig it up with the "streetlight ports", so it comes on when charging.

I appreciate the advice, I didn't think too much about heat from the MPPT!
 
I have a second thermostat (Amazon 2 pack!) that I use for my heating pads, and I might try to rig it up with the "streetlight ports", so it comes on when charging.
Can you tell me more about these? I saw the streetlight function in the Victron app but haven't looked up what it does. As for the thermostat, is that just a fan + speed controller + temperature probe so it comes on automatically when it gets warm? I ordered a fan but haven't figured out the speed control yet; whether that's a knob or something automatic and temperature-based.
 
Can you tell me more about these? I saw the streetlight function in the Victron app but haven't looked up what it does. As for the thermostat, is that just a fan + speed controller + temperature probe so it comes on automatically when it gets warm? I ordered a fan but haven't figured out the speed control yet; whether that's a knob or something automatic and temperature-based.
I have one connected to a heating pad, but I imagine adding a 12 volt PC fan would work the same.


I really don't know a ton about the ports on the Victron, but I know they can be customized to turn on and off with certain parameters. I was thinking to save power, have it kick the thermostat on only while it has PV power, and let the fans cool it when needed.
 
I really don't know a ton about the ports on the Victron, but I know they can be customized to turn on and off with certain parameters.
Oh I see, you mean using the "load" ports on the 100|20 MPPT? I have the 100|50 and I don't think it has a load output. I guess the "streetlight" name implies stop/go signaling...

Thanks!
 
Oh I see, you mean using the "load" ports on the 100|20 MPPT? I have the 100|50 and I don't think it has a load output. I guess the "streetlight" name implies stop/go signaling...

Thanks!
Yes, I'm pretty sure they are mostly used to turn a light on, or off, at sunset or sunrise (dictated by PV voltage). Instead of a light, it would be the temp controller.
 
Nice work. Can't believe you spent the money on a Victron controller for this. A much cheaper controller would have been fine for a portable generator in a Plano box.
 
Nice work. Can't believe you spent the money on a Victron controller for this. A much cheaper controller would have been fine for a portable generator in a Plano box.
Why? I like the features of the Victron, and I use 60v solar panels on a 12v system, not a ton of options for that setup.
 
Why? I like the features of the Victron, and I use 60v solar panels on a 12v system, not a ton of options for that setup.
Victron SCC ? they continue to write new firmware

i built my practice 4S 100Ah LFP circuit into a white wooden cabinet from home depot with open side upwards with double gasket on the seam and a Victron 100/30 or something accepting input from 2x 300W panels. Enclosed inside, it would warm up when charging at max rate. Warm enough that I put a 140mm pc fan on the backside.

Without any fan, I found that dialing back to 22A on my 30A rated victron MPPT caused no appreciable heat build up in the enclosed space.

Cool box!
 
I have nothing against the Victron controller... I think their products are great. I am not made of money though, so I use the nice one for my camper, my house, or something else like that. For my DIY solar box I just use a cheaper one to save some money. That's all.
 
I have nothing against the Victron controller... I think their products are great. I am not made of money though, so I use the nice one for my camper, my house, or something else like that. For my DIY solar box I just use a cheaper one to save some money. That's all.
No offence taken, no worries! ?

I use my solar box for power outages and it's the primary source of power in my tiny trailer / camper. For me, that box is "mission critical", and I want it to work when I need it.

I bought nice equipment BECAUSE I don't have a ton of money. I would rather buy something nice (and expensive) once, rather than have to replace parts and wires in cheap stuff constantly. The Victron was an "open box" on Amazon too, it was ~$75 off.

I budgeted and sold extra cells and BMS's I ordered from China on eBay to defray costs as well.

I've tried the "cheap" route, and found myself not being happy with inaccurate shunts (bought 3 different ones), cheap PWM SCC's (have 3, the Victron charges at ~25 amps, the PWM's never go over 9a, because I have 55v panels), and I ended up replacing all of my underrated fuses with used class T's from eBay.

I tried to get cheap wire, ended up getting ripped off with copper clad aluminum, didn't realize what it was, and had to rewire EVERYTHING, with actual copper. Because I tried to be cheap, everything ended up costing more in the end.

Cheap and Lithium don't mix IMHO. Lithium is very powerful, and can dump an EXTRAORDINARY amount of juice. I don't trust (some) low-cost products to protect my family when we are sleeping literally on top of that box in the "camper".

The more I learn, the more I realize that those cells can be very dangerous.
 
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