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280ah Lifepo4 Leisure Battery - Build Thread

Mrdanielmh

Solar Enthusiast
Joined
Apr 19, 2020
Messages
177
Hello!

I wanted to start a build thread for my leisure battery, as I think it might be really helpful for beginners in the future. I'm am an absolute beginner and am hoping to show that it can be done, and you don't have to spend thousands of dollars/pounds on a pre-built battery. I'll post some pictures of my rig too as I start to install things!

Components - What will I need!

Cells
- 4 x 3.2V 280Ah Lifepo4 Cells (http://tiny.cc/zd2mnz)
BMS - 120Ah Bluetooth Lifeop4 Battery Management System with Low Temperature disconnect (Amazon Link on this page: https://www.mobile-solarpower.com/raw-lifepo4-deals-page.html or can be sourced from Aliexpress/Alibaba)
High Temperature Tape - Tape to bind the above cells together before fitting into a battery case (http://tiny.cc/xp3mnz)
Battery Terminals - 5/16” Stud Premium Remote Battery Power Junction Post ( )
Battery Case - Work in progress! Likely a home made solution


My understanding (from a noob point of view!) is that the above components will give me a full functioning Lifepo4 Leisure Battery!

Schematic - What will it look like?

1587668676823.png

Any feedback is greatly appreciated!

Thank you,
Daniel
 

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Hello.

Not experience with Victron systems, but:

I guess the little black things in the positive output of the battery are fuses?, if so.. why not put only 1 to the main line?. Also this main line should be conected to the battery protect, so it can disconect all the loads if necesary.

Also i dont see a battery disconect.

Greetings!
 
Thank you @mrdavvv - the little black things near the positive terminal are midi fuses. I thought it made sense to fuse everything seperately so that if 1 fuse blew I still have other charging capabilities.

I thought the Victron Battery Protect was for load, so I only had it attached to the fuse box load so that it would shutdown access to appliance if the voltage of the battery was too low.

When you say battery disconnect, is that the same as described above?
 
Hello!

I wanted to start a build thread for my leisure battery, as I think it might be really helpful for beginners in the future. I'm am an absolute beginner and am hoping to show that it can be done, and you don't have to spend thousands of dollars/pounds on a pre-built battery. I'll post some pictures of my rig too as I start to install things!

Components - What will I need!

Cells
- 4 x 3.2V 280Ah Lifepo4 Cells (http://tiny.cc/zd2mnz)
BMS - 120Ah Bluetooth Lifeop4 Battery Management System with Low Temperature disconnect (Amazon Link on this page: https://www.mobile-solarpower.com/raw-lifepo4-deals-page.html or can be sourced from Aliexpress/Alibaba)
High Temperature Tape - Tape to bind the above cells together before fitting into a battery case (http://tiny.cc/xp3mnz)
Battery Terminals - 5/16” Stud Premium Remote Battery Power Junction Post ( )
Battery Case - Work in progress! Likely a home made solution


My understanding (from a noob point of view!) is that the above components will give me a full functioning Lifepo4 Leisure Battery!

Schematic - What will it look like?

View attachment 11673

Any feedback is greatly appreciated!

Thank you,
Daniel
The Negative leads from the MPPT, Orion, and Smart charger must be connected at the same shunt terminal as the Load fuse box. If they are not, the monitor will not see the charge or loads.
 
Hi @JC777 - Thank you for your reply! I thought that the BMV-712 Monitor Shunt was only supposed to be on the load side - ie appliances. Does it also monitor what is coming in from the charging sources too?
 
Thank you @JC777 - in that case would you recommended a positive and negatove busbar off of the battery terminal to join everything together and place the shunt between negative busbar and terminal?
 
Perfect, thank you. Ill re do my design. Presumably im going go neef some big cable between busbsr and terminal
 
Each charging source max output is 30 amps x 3 = 90 amps. #10 stranded will be the minimum wire size I would use.
The DC Load box is the only Item in your drawing that doesn't have a amp load value.
 
Here's how I would do it.

12 VDC BATTERY NEG to SHUNT.
SHUNT to BUSBAR
All charging and load terminals to BUSBAR
BUSBAR to REMOTE BATTERY POST.

12 VDC BATTERY POS to MANUAL DISCONNECT.
MANUAL DISCONNECT to MAIN FUSE
MAIN FUSE to BUSBAR
All charging and load terminals to BUSBAR
BUSBAR to REMOTE BATTERY POST.

You might consider mounting the Manual Disconnect on the exterior of the battery box.
If you are a little bit handy, you could use the extra bussbars that come with the battery to make your own distribution busbars.
How far from the battery is your Load fuse box?
If all of your components (except for the Load Fuse Box) are in the battery box, you could delete the Remote Battery Posts. The Load Fuse Box could be wired directly to the distribution busbars. It all depends on your installation needs/wants.
 
Thanks for the detail @JC777 !

I was planning to only have the cells and BMS in the battery box and then all other components on the outside.
All of the components will be within 50cm of the battery!
 
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