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Are the battery loads not connected to a BMS inside the plastic housing? Because I want to connect my cells in parallel within the pack.

I'm about to build a new battery 4P16S, 280Ah which will be connected to 3x Victron Multiplus II 5kVA inverters in 3-phase. My potential, continuous load from the inverters will be ~350A and finding a BMS capable of handling this load will be very difficult. I realise that what I'm about to say...

It was fun to build. I'm not sure what hardware version he's up to now but I built v1 or v1.1 from memory.

I use a lot of power: 3 phase Tesla charger @ 12kW, large ducted A/C, pool equipment, 30A induction cooktop etc. You get the picture. I've already built the DIYBMS but I'm looking for something which will talk to my Victron gear and something less modular. I'll keep looking around, thanks.

I'd prefer to use contactors rather than MOSFETs so I'll look for another BMS. Yes, my inverters draw up to 400A - 3x Victron MultiPlus II 5000kVA in three phase.

I'm interested in this BMS but my inverters will draw up to 400A from my battery so the 200A version won't suffice. Is it possible to pair it with a contactor? ie. Is there a low voltage signal one can use to open/close a contactor?

I've bought a bunch of 0.2Ω 100W power resistors from Aliexpress for around $2 each. 3 in parallel will draw a total of 48A (50W at each resistor) at 3.2V nominal which will suit my testing purposes. I'll buy a few of these capacity testers so I can test a few cells concurrently.

I found out after the fact that 2 of my 48 cells had a much higher internal resistance and lower capacity (tested at ~260Ah vs the others being ~280Ah). Had I picked this up soon after receiving the cells I could have raised a dispute with the vendor and/or credit card company.

I agree that an inverter/shunt would be ideal but I won't be able to test single cells using an inverter (my Victron MultiPlus II 48/5000VA has a minimum DC input of 38V) hence the need for a device such as the DT24P which can test single cells at lower voltages but still draw a high current load.

I'm actually referring to the DT24P, not the DL24P. Uses a shunt and supports up to 100A loads (use a power resistor bank) and relays to shut off the load at a programmable low voltage mark. Link to Aliexpress seller...

Hi, did you find out if you can use ANL fuses with the Victron Lynx?

I've got a DL24 already (works fine) but I was after a tester which can pull more load from the source which is why I was interested in the DT24P. Anyway, I hope you can resolve your issue.

Note: This thread is about the DT24P not the DL24P (with the large fan) I'm about to start building my second hybrid solar system (sold my home and building a new one) and one of the things which I wish I did on my previous build was to test the 280Ah LiFePO4 cells prior to putting them into...

Thanks Bob. Yes, I read about the issues with powering the BMS via the sense wires and the fix of powering the BMS externally. I'll take your advice and keep an eye out for the new version.

Does anyone have any feedback on the Chargery BMS? I noticed that they have a new-ish product called the BMS16 v2.0 which appears to have integrated the LCD into the BMS itself. I'm interested in this BMS because of the seperate ports and the ability to wire the charge and discharge signal wires...

I'm about to start my solar & battery build and I'm currently looking at BMS's for it but it's proving to be challenging to find a BMS which can accomodate my potential charge current. A little background on my build: I've got 21kW of panels. 16kW of those panels feeding into a 3-phase Fronius...

Agreed - the discharge curve on LiFePO4 cells is extremely flat. My point is that the 280Ah claim of this cell is made based on a full charge and discharge of the cell from 4.2 - 2.5V at a low C discharge and unless one does tests within that range, we're not likely to see that 280Ah figure...

Thanks for doing these tests. I think if you were to charge and discharge these cells to the specified voltage limits that you'd achieve the advertised capacity. What I find interesting is that these cells are supposed to be the same as all the other 280Ah cells advertised on Alibaba...

Great point regarding the vent hole - I've added it into the design. You don't happen to have the dimensions of this do you? Length to the ends of each arc and width would be great! Not sure what to do about the busbars, it's possible that the sellers might be able to provide longer ones...

Thanks for the dimensional drawing Steve. I'll adjust my design for the centre-to-centre terminal distances. There's plenty of room for busbars and terminal clearances via cutouts - see circled red area in the image below.

Great, thanks for these mate! They worked out pretty close using your 87mm centre-to-centre distances. Here's some of the dimensions which I've got

Digital callipers will be perfect for getting dimensions - I can add a little wiggle room in my designs. Are you able to provide the dimensions I asked for? I did go back to the previous posts but I was struggling to understand some of the measurements and I think I need additional measurements...

If the cells are packed next to one another, the aluminium will act as a heat sink and absorb all the thermal energy from all the adjoining cells. The more thermal energy one can dissipate through passive or active ventilation, the better for the battery. The battery will perform better and last...

Dimensions are above (based on dimensions provided by the Alibaba listing. By using these, they will allow a 10mm gap between each cell for ventilation. These cells should be ventilated for both performance and longevity, especially if you're planning on running large loads from them.

I've updated the design to include dovetails/interlinks on all sides. I've done away with doing flat ends because it would mean too many variations of the design at this point. Can do this later if/when I get accurate dimensions. I still really need accurate dimensions for the following...

If you click on the link provided there's different versions for the ends which don't have interlinks.

Easy to add those, I'll do it tomorrow.

I've designed some cell spacers for these cells. They're designed to allow for buildings packs by locking the cells together and also providing a 10mm spacing between each cell to allow for ventilation. The only issue is that I don't have these cells yet so I've had to guess the dimensions. If...

Does anyone have any dimensional drawings of these cells? I'd like to create 3D printable spacers/holders for building packs.

I'm not preaching. It appears you're taking offence to someone who's made some casual observations about some potential safety issues I've seen on this thread which seems bizarre and irrational. What facts aren't "straight"? The fact that I didn't mention AC/DC breakers? A nominally intelligent...

Fuse/breaker. Old habit from the days where homes used to use ceramic fuse housings with fuse wire.

The problem is that these "pitfalls" have the very real potential to be fatal. Whilst the chemistry might be safer with LiFePO4 cells over Li-Ion, the risk remains that if people don't know what they're doing, they run the risk of incinerating themselves and/or their families. There's plenty of...

I've been reading this thread with interest since I'm considering purchasing a large quantity of these 280Ah cells and I've noticed a recurring theme on fuses. Fuses exist to protect 2 critical elements of an electrical system: 1) to protect from overcurrent from a power source within the...

I suggest that you buy a proper balancing charger and pair it with a quality 1000W (36V @ 30A) DC power supply. This just looks like a voltage regulator paired with a power supply - there's no intelligence in that package. These ISDT 1000W chargers have been reliably used within the FPV market...