diy solar

diy solar

My DIY 48V Battery Box Build.

Sanwizard

Solar Wizard
Joined
Feb 2, 2021
Messages
2,660
Just wanted to share some initial pics of the battery box build. Still waiting for 16 cells from Michael before I can finish it.
First 16 cells charged and to balanced. 48V capable battery switch (sure wish Blue Sea Systems had a 48V switch!), precharge button and shunt monitors installed. Next step on internals are BMS, Fuse, terminals, and Raspberry Pi connectivity and programming for the BMS. I will be using Jblance gitgub code, just like DMI.
 

Attachments

  • 20210425_153914.jpg
    20210425_153914.jpg
    228.1 KB · Views: 273
  • 20210425_153901.jpg
    20210425_153901.jpg
    330.1 KB · Views: 222
  • 20210425_153850.jpg
    20210425_153850.jpg
    297.2 KB · Views: 238
  • 20210419_152925.jpg
    20210419_152925.jpg
    105.4 KB · Views: 267
  • 20210422_140713.jpg
    20210422_140713.jpg
    203.3 KB · Views: 278
That's excellent, very good indeed. I'd like to know your materials list, and how you plan to insulate or pack and bind the cells in the box. Please keep us posted!
 
That's excellent, very good indeed. I'd like to know your materials list, and how you plan to insulate or pack and bind the cells in the box. Please keep us posted!
No need to pack the cells. 32 cells will fit perfectly tight with rubber padding glued to all sides and bottom, plus a sized piece of rubber matting between each cell. I am using 1/2 cutting board over the cells to prevent shorts. The BMS will sit on top of yet another cutting board with the shunt and fuses. The square pieces of rubber between the cells is from a $10 roll from home depot. I used Gorilla glue spray to hold the rubber on the walls and floor of the toolbox. The 272ah Lishen cells are a perfect fit inside the toolbox from Amazon.

TUFFIOM 48 inch Heavy Duty Aluminum Truck Tool Box, Trailer Pickup ATV Truck Underbody Bed Storage Toolboxes w/Lock & 2 Keys, Rectangle (48 inch)​

 

Attachments

  • 1619404358576650687419148773736.jpg
    1619404358576650687419148773736.jpg
    169.8 KB · Views: 107
  • 20210425_223041.jpg
    20210425_223041.jpg
    82.9 KB · Views: 103
  • 20210425_223020.jpg
    20210425_223020.jpg
    84.7 KB · Views: 103
Thanks for sharing, looks like you're off to a great start. I've been considering HDPE for strength and insulation.
 
Howdy, can you provide any more pics of your setup? What is your 48v battery configuration?

Links to your BOM list?

You still using that Riden?
 
The Riden is waiting on my additional cells to start top balancing again. The box is only half full at the moment.
 

Attachments

  • 16233345529186781353340995262569.jpg
    16233345529186781353340995262569.jpg
    233.4 KB · Views: 123
  • 16233346267587880725106683278501.jpg
    16233346267587880725106683278501.jpg
    161.2 KB · Views: 118
  • 16233346472801318117307245612653.jpg
    16233346472801318117307245612653.jpg
    147.5 KB · Views: 130
  • 16233347059939120836160727956379.jpg
    16233347059939120836160727956379.jpg
    143 KB · Views: 120
  • 16233347200538577345291847776768.jpg
    16233347200538577345291847776768.jpg
    139.4 KB · Views: 117
Each battery has its own switch and AiLi shunt with monitor on the front of the box. I have a Victron shunt connected to the busbar across both batteries in the box above the battery box. I will send a schematic of the connections.
 
Here is the diagram. I did an 8x8 config, as it is the most compact. It enables me to fit 32 cells in one 48" toolbox, with room for all the connections, fuses, shunts, Facon heaters, and BMS's.
 

Attachments

  • Solar System Diagram.jpg
    Solar System Diagram.jpg
    192.1 KB · Views: 127
Thanks, love the "Danger high voltage" sticker.

If my32 batteries r e a l l y show the hells up tomorrow I want to be about making a compression box for them.

I decided to go all Victron / Orion parts and everything will be stubbed out beside my bed pedestal in my RV. The space for the box is about 17" x 48" so planning on 2 wide and 16 deep.

I'm 2P/16S and this box will be visible so I want to make it look nice. I already have 4 of the diamond plate storage cabinets from HF in my main area, but they are somewhat greyish in color so prob can't match it.
 
I would stay away from parallel if you can. No way to monitor every cell. I like that ability with a BMS for every 16s pack.
With lead acid its not a problem, but these cells can run away on you.
 
I was waiting on that sentence :D I could go active balancers but I dunno if I want to spend the money.
 
I would stay away from parallel if you can. No way to monitor every cell. I like that ability with a BMS for every 16s pack.
With lead acid its not a problem, but these cells can run away on you.
So essentially you are building two batteries running to your inverter instead of one large battery? 16s x 2
 
So essentially you are building two batteries running to your inverter instead of one large battery? 16s x 2
Correct. They connect in parallel at the busbar. This way I can keep expanding 16s at a time. Two 16s batteries fit perfectly in the Tuffiom toolbox from Amazon. I added precharge and battery cutoff switches, and also a shunt based monitor for each battery. The busbar connection is in the box above the toolbox, where I added a Victron shunt to monitor flow through both batteries. ( I since added another LV6548 also)
 

Attachments

  • 20210516_135033.jpg
    20210516_135033.jpg
    131.3 KB · Views: 59
Correct. They connect in parallel at the busbar. This way I can keep expanding 16s at a time.
How is this different than having a 2p16s battery? What is the benefit to doing it like you have instead? I'm new at this and am still trying to figure it all out.
 
When cells are put in parallel, you get more amp hours, and its less expensive. There are always tradeoffs though. When in put in parallel together as one battery, you cannot monitor each cell individually. A bad cell may not go noticed until the entire battery pack is affected.
I like to know how each cell is behaving. Also, using two packs with individual BMS's provides a bit of redundancy and flexibility. You can take one 48V pack out of service to work on it, while the other pack provides power.
 
How is this different than having a 2p16s battery? What is the benefit to doing it like you have instead? I'm new at this and am still trying to figure it all out.
Take a look at "off grid garage" on youtube. Andy went through the same thought experiment, and decided on individual battery packs, each 16s with its own BMS. He covers the benefits of each approach.
 
Back
Top