diy solar

diy solar

Shelves for 3x 280Ah 48v LiFePO4 Banks?

Very nice. I like the way you installed it so you can stack them if needed, and still have access. I used a very similar box, but its from the top, so I cannot stack.
Nice setup too! Are the buttons on the front for priming the inverter's capacitors through a resistor before closing the battery switch? I'm thinking of doing that with each pack to avoid having to do anything risky with live cables, and to avoid stress on the inverter's threads from removing and reattaching the battery leads.
 
Nice setup too! Are the buttons on the front for priming the inverter's capacitors through a resistor before closing the battery switch? I'm thinking of doing that with each pack to avoid having to do anything risky with live cables, and to avoid stress on the inverter's threads from removing and reattaching the battery leads.
Yes. Those are pre-charge buttons with in-line resistors to charge the inverter capacitors prior to turning on the battery power switch. Makes it nice and easy when doing maintenance.
 
I was thinking also galvanized steel for pillars and plates. Have the sellers, have the prices. It is cheap. All steel material is about $400-$500.

I was playing a bit with SolidWorks to make a plan with complete steel thickness for pillars and plates (and statical analysis, bending under the weight, maximal bending of the shelves) ... but give up.
The hard part is to make it really water resistant (without welding everything together).

On the top easy, just a bottlecap going down a little bit on all 4 sides.
The side-rear panels can bend on the ends and overlap. No big deal.
But the door ... the frame has to be this beak nose ... and with a double door that sliding into that ... too much for me


True. I checked up some and I was in a lot server rooms before. They are deep and not wide.
Also full with holes (and even used ones are expensive)



Gun cabinets, safes, filing cabinets. Not joking already checking used items :LOL:

But at the end if I am not too lazy (and buy the small battery and inverter cabinets) then I can weld the cabinet together myself.
... but I am too lazy and too busy for that.
So I saw a video of a guy who used these Kobalt Job Site boxes as an outdoor waterproof cabinet for his Nissan Leaf cells. I cannot find the link at the moment, but this link is a similar box. Great for just the battery cells in an outdoor setting.
 

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So I saw a video of a guy who used these Kobalt Job Site boxes as an outdoor waterproof cabinet for his Nissan Leaf cells. I cannot find the link at the moment, but this link is a similar box. Great for just the battery cells in an outdoor setting.
Neat idea in the linked video. I'll have to look for the video of the guy with the Nissan Leaf cells.
 
Those are 230 amp EVE cells.

The inside of the box is lined with self adhesive neoprene.
https://www.amazon.com/dp/B0774DKKXV/ref=cm_sw_em_r_mt_dp_EV6YG529TFSDH07XV5EQ?_encoding=UTF8&psc=1

closed up and finished, it looks good.
Very nice setup! I forgot to ask if you used any compression for the cells, or if you just used the tape to keep them somewhat bound. I'm still on the fence about compressing them, but I figure if I have room it will help stop them from stressing the terminals during any potential expansion.

What model is the Growatt?
 
Very nice setup! I forgot to ask if you used any compression for the cells, or if you just used the tape to keep them somewhat bound. I'm still on the fence about compressing them, but I figure if I have room it will help stop them from stressing the terminals during any potential expansion.

What model is the Growatt?
I wrapped the cells in two rows of filament tape, then overwrapped with capcom tape. The cells aren't technically under compression but they won't expand either. There is a sheet of fiberglass reinforced silicone baking mat between each cell so I don't have to worry about a failure in the blue wrap causing a short. I did this in packs of 4 cells to make them easier to handle. I offset the two rows of tape to minimize the space between the packs.

The Growatt is a 48V 6000T 6kW split phase. So far the thing is a beast! It easily runs the whole house, including the mini split AC.
 
I wrapped the cells in two rows of filament tape, then overwrapped with capcom tape. The cells aren't technically under compression but they won't expand either. There is a sheet of fiberglass reinforced silicone baking mat between each cell so I don't have to worry about a failure in the blue wrap causing a short. I did this in packs of 4 cells to make them easier to handle. I offset the two rows of tape to minimize the space between the packs.

The Growatt is a 48V 6000T 6kW split phase. So far the thing is a beast! It easily runs the whole house, including the mini split AC.
I'm strongly considering going with a cheap truck box solution, especially after seeing yours and Sanwizard's setup pics. I can purchase 3 for about $500-$600 total before shipping. They should be here landed for under $1k total, which would be a fraction of the cost of my original custom shelf setup. They'll be thin and cheap but won't be exposed to the elements or moved, so I don't expect to have corrosion issues for years to come. Looking at 30' x 17' x 18' to keep them somewhat small, but give me a bit a room for the BMS, fuse, and switch. I think it'll be the cheaper and easier route to go with.
 
You need 48" to fit 32 x 280ah cells, which is a @26KW battery. The Tuffiom 48" toolbox has just enough room for heating pads for each bank also, and plenty of room for BMS, pre-charge buttons, power switches, fuses, shunts, etc.
I like the way Brett V did his with the opening horizontal vs on top, as they can be stacked that way.
 
You need 48" to fit 32 x 280ah cells, which is a @26KW battery. The Tuffiom 48" toolbox has just enough room for heating pads for each bank also, and plenty of room for BMS, pre-charge buttons, power switches, fuses, shunts, etc.
I like the way Brett V did his with the opening horizontal vs on top, as they can be stacked that way.
I am thinking of organizing the cells as 24" x 14" blocks instead of one long string. I was thinking one box per battery, 3 boxes total. (48 cells, 48v packs) I shouldn't have to worry about accommodating a heating blanket as the lowest temperature on record here is 43.6F (6.4C).

I like the front opening as well. Still trying to decide if I want to stack them or have them side-by-side. I'm planning on having one common shunt that all batteries will go through after they join at a bus bar. If I have the boxes all lined up instead of stacked, I'll be able to have the wires exit on the top. I've also considered stacking them on their sides almost like a locker. I could keep them close to each other, but it would have the lowest floor footprint and lowest height combination. The wiring exits, switch, and priming button would fit well too. (The units I'm looking at have flat sides with no handles.) The disadvantage to this is having to position the cells on their sides instead of upright. :unsure:
 
Keep them upright. I agree laying them on their side is not good for the electrolyte.
I also agree straight line 16S is not as space effective. I did mine 8x8 as depicted in the diagram. Both banks connect to a common busbar, which os where the global Victron shunt is. I also used the cheaper AiLi shunts for inside the box to monitor state of charge of each bank.( the round displays inserted into the box). The Victron shunt and busbars are in the enclosed elecrical box above the batteries.
 

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Keep them upright. I agree laying them on their side is not good for the electrolyte.
I also agree straight line 16S is not as space effective. I did mine 8x8 as depicted in the diagram. Both banks connect to a common busbar, which os where the global Victron shunt is. I also used the cheaper AiLi shunts for inside the box to monitor state of charge of each bank.( the round displays inserted into the box). The Victron shunt and busbars are in the enclosed elecrical box above the batteries.
The Plano storage boxes look like they could work. They even have wheels on one end :

black-plano-storage-trunks-pla108hd-64_145.jpg
 
The Plano storage boxes look like they could work. They even have wheels on one end :

black-plano-storage-trunks-pla108hd-64_145.jpg
Plano makes great stuff. I have their large rifle cases for my 338 Lapua Magnum, and its built like a tank.
 
The Plano storage boxes look like they could work. They even have wheels on one end :

black-plano-storage-trunks-pla108hd-64_145.jpg
It would most likely work quite well, but I need the cells enclosed in metal to pass code here.
 
It would most likely work quite well, but I need the cells enclosed in metal to pass code here.
Never heard of that. Are you in the US? Many inspectors here would not know what they were looking at if they saw a DIY bank.
 
Never heard of that. Are you in the US? Many inspectors here would not know what they were looking at if they saw a DIY bank.
Bermuda. It's somewhat of a grey area as powerwalls aren't extremely common due to the ridiculously high cost. (Most items here are marked up 150-260% from shipped and taxed value.) Any higher voltage DC lines have to be enclosed in metal conduit. As the cells essentially have exposed contacts, they need to be shielded in metal. Outdoor (non living space) runs or in-wall runs can be through PVC conduit. As the cells will be in the garage instead of outdoors, I'll need a metal enclosure. I don't want to argue with one of the two electrical inspectors on-island...I need his sign off for a government rebate for the solar install, and to keep the insurance company happy. Speaking with an electrician, his advice was to encase the cells in metal to "cover my butt" and avoid any issues. I'd also prefer a hard enclosure solution to keep the kids out and provide more protection from something potentially bumping into them.
 
Bermuda. It's somewhat of a grey area as powerwalls aren't extremely common due to the ridiculously high cost. (Most items here are marked up 150-260% from shipped and taxed value.) Any higher voltage DC lines have to be enclosed in metal conduit. As the cells essentially have exposed contacts, they need to be shielded in metal. Outdoor (non living space) runs or in-wall runs can be through PVC conduit. As the cells will be in the garage instead of outdoors, I'll need a metal enclosure. I don't want to argue with one of the two electrical inspectors on-island...I need his sign off for a government rebate for the solar install, and to keep the insurance company happy. Speaking with an electrician, his advice was to encase the cells in metal to "cover my butt" and avoid any issues. I'd also prefer a hard enclosure solution to keep the kids out and provide more protection from something potentially bumping into them.
Yeah, that's why mine are in a metal lockable box. You have to insulate the insides of the box with heat resistant non electrical conductive material, bottom and sides, and in between each cell. I just used thicker cutting board material on top of the terminals to mount the BMS and other connections. Worked out great. You most likely will not need the heat pads for when it snows though.....
 
I went with the 16 cells in a straight string to keep everything as close to the wall as possible because this is in my garage and I don’t want to be banging the car door in to it. The build was a bit more tedious with the door opening in the front instead of on top but I’m glad I went this way.
 
I think I'm going with this model for my boxes. Leaning towards the 30" model, but I know it's going to potentially be tight. I'm not sure how well they'll stack, as I suspect that the bottoms will bow with the weight of the cells. Hopefully a piece of 3/4" ply internally will stiffen it up a bit. Alternatively, If I set them side-by-side like lockers, I can stack the cells in 2 rows of 8 cells high and won't have to worry about wondering if they'll hold the weight over time. I spoke with the supplier for my EVE cells and they said their engineers say it should be fine, but not too many...they never answered 'how many is too many?' I figure it'll be a tight fit to get the cells in there depending on what I do with compression, but I should have a bit of space above the terminals regardless. My thinking is: 10' above each cell minus space taken by rigid base, and space away from the edge of the enclosure...soooo ~ 6" will be available for the BMS (approx 2" x 5" x 8"), fuse, switch, and pre-charge resistor + button.

Line the boxes using 1/8" neoprene foam with adhesive side. Neoprene Foam

I've been toying with using thin plastic cutting boards (sheets), neoprene foam, neoprene solid rubber sheets, or fish paper as insulation between each cell. I found something that's a bit different than fish paper, but I think it will do. This stuff is used in the assembly of 18650 packs. It's 7" wide, so I'd only have to cut it into 8" sections to match my cell size. One side can be stuck to one cell's side and will provide an additional insulating layer that won't slip out of place.

Thoughts or considerations for the above?
 
I think I'm going with this model for my boxes. Leaning towards the 30" model, but I know it's going to potentially be tight. I'm not sure how well they'll stack, as I suspect that the bottoms will bow with the weight of the cells. Hopefully a piece of 3/4" ply internally will stiffen it up a bit. Alternatively, If I set them side-by-side like lockers, I can stack the cells in 2 rows of 8 cells high and won't have to worry about wondering if they'll hold the weight over time. I spoke with the supplier for my EVE cells and they said their engineers say it should be fine, but not too many...they never answered 'how many is too many?' I figure it'll be a tight fit to get the cells in there depending on what I do with compression, but I should have a bit of space above the terminals regardless. My thinking is: 10' above each cell minus space taken by rigid base, and space away from the edge of the enclosure...soooo ~ 6" will be available for the BMS (approx 2" x 5" x 8"), fuse, switch, and pre-charge resistor + button.

Line the boxes using 1/8" neoprene foam with adhesive side. Neoprene Foam

I've been toying with using thin plastic cutting boards (sheets), neoprene foam, neoprene solid rubber sheets, or fish paper as insulation between each cell. I found something that's a bit different than fish paper, but I think it will do. This stuff is used in the assembly of 18650 packs. It's 7" wide, so I'd only have to cut it into 8" sections to match my cell size. One side can be stuck to one cell's side and will provide an additional insulating layer that won't slip out of place.

Thoughts or considerations for the above?
Sounds like a plan. As long as it fits. I have two sets of 8x8 for 32 280ah Lishen cells in a 48" box, with the cells upright, and it JUST fits. Plenty of room from the terminals to the top of the box, but just enough to squeeze in the insulation paper, and heating pads along the sides.
 
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