DIYBMS for Lithium Iron Phosphate battery cells (LiFePo4) 280aH

Vassilis, the post spacing is 89mm.

centre of the oval hole to the other is indeed 89mm. Haven’t touched Jau’s dimensions…
Will fit to 90mm posts as well as holes are oval.


ok thanks

Hi Mike, would you post to the UK? If so I would definitely like them

If you are willing to pay the shipping costs I’ll send them over, however, I’d suggest combined shipping for a couple people in the UK (or surrounding area) to reduce the overall cost of shipping. From USA → UK for USPS International Priority Mail it would be just over $40 USD. Any applicable VAT/Customs costs would need to be paid on receiving end.

Sorry, I have just realised this is the ‘cell module’ thread and not the shunt thread - are you selling cell modules or shunts? I’ve got controllers and lots of modules, I just can’t find all the parts for the shunts so I haven’t even ordered any from JLC yet

I only have shunts available currently. I am looking at ordering a few more modules but no timeline for it yet.

First of all, let me say, fantastic work everyone!

The wife and I are completely off-grid. We currently live off 1, 12v/100ah battery and are eagerly waiting for our new cells to arrive.
The cell we are getting are EVE LF230 prismatic cells(64). These cells have a 123mm spacing.
Has anyone modified the hole spacing to match these larger cells?

I had a go a month or so ago, but ended up getting different cells with 90mm spacing and left that.
If you don’t mind waiting for my modules to arrive and be tested (…couldn’t even order them due to lack of components!), I can add the extra bit on the side and stretch it to 123mm

Thant sounds great! Waiting’s not a problem. The cells are on the mainland till March anyway. Hopefully there’ll start to be some stability to the supply chain by then (but I’m not holding my breath).

Ordered the 10 I need a couple of days ago, should hopefully have them in 10days or so. When I do, I’ll check that they are fine (should be!) and then publish the 89-90mm and the 123mm files. ATM only things missing are the connectors (easy) and the ATTiny chip (also reasonably easy to do with a decent soldering iron)


quick question,

just noticed that JLC have decided to turn round ALL THREE diodes in the board :frowning:

and the wrong one they are planning to built:

zoom in on D1, D3 and D4 :frowning:
is there anything I can do to change their mind?
that’s from the DFM Analysis popup screen which doesn’t seem to have any option to feedback…

there is only this “welcome back, may I help you?” chat thing on the bottom right hand corner of the screen



too tired last night, I was wrong, they corrected it :slight_smile:
all fine, will report once I get them in my hands


while waiting for the modules to arrive from JLC, I had a go at a multi spacing LifePO4 module:

looks a bit odd but could be a universal solution to the various terminal spacings on cells. The 72mm is the hardest to achieve without reorganising the whole lot in the board (wasn’t ready to do so…)



Hi, where could i get gerber, bom and jlc files for lifepo4 module? Thanks guys

I went the cheap way and made adapters instead


just an update,

received a new batch of LifePO4 modules with a couple of components changed due to stock issues. Works but balancing red led doesn’t turn on due to the slightly different properties of the mosfet driving the process. Balancing works (slightly differently though…)
Anyway, replaced the mosfet with the old one, works fine, led works as it should.
Now trying to figure out an alteration on the two resistors driving the mosfet to sort it out. If it works, I’ll post gerber et al hopefully by the w/e.
BTW, in the meantime I altered yet again the PCB to accept anything from 72 to 123mm post spacing. Looks odd but should be fine :slight_smile:

so more news when I’m done with that.


I must admit i’m not using this type of module (i’m using the stock modules) but to me you would be much better to put the busbar below the modules to minimise connection losses.

+1 planning to get the busbars first with a thin flat nut, and then put the modules on top and secure them with another thin flat nut. Else you end up getting most of the current through the module PCB and the via’s or platting there which is pushing things a bit imho

Thanks for the advice, didn’t really think about that while I was testing the setup.


after various tests and builds I’ve come up with two “evolutions” to @Jau design. Evolution is a big word, basically rearranging a few bits to make things happen. Only item changed from his original design is the D1 which is out of stock on JLCPCB. Ah, and added the external TempSensor in a way that it’s easy to cut away but since it’s actually connected with tracks to the ext connector JLCPCB consider it as one board and wont charge extra. Even if you don’t cut it off it will report temps (admittedly quite similar to the internal sensor ones…)


which adds a larger oval on the pads where the battery terminals fit enabling easier 89-91mm spacing and adds jumpers to be able to disconnect the module for updating firmware without taking the whole battery apart.

Zip file to send to JLCPCB (unzip the file and there’s the gerber and the two csvs): (109.3 KB)
and for anyone who wants to play with it the json that loads straight into EasyEDA: (119.8 KB)


second version goes a bit further by enabling terminal spacing from 72 to 123mm. Main reason for doing it is that EVE 304 changed to 123mm spacing out of the 90mm and seems to be impossible to know for sure what you’re actually ordering from China… Considering that shipments from there take 2m+ I feel it’s better to be safe than sorry.

Zip file for JLCPCB: (109.4 KB)
and json that loads into EasyEDA for editing: (118.7 KB)

NOTE- Missing bits:
ATTiny (as always…)
Q1 Mosfet (tried another one but didn’t work, so has to be ordered separately, it is available and relatively easy to solder)
JST-2-PTH side connectors also missing, easy to solder and decide which side (or one each) suits your setup.

thanks to all involved hope that helps someone!


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