Idiot's guide to a self build battery

[nowty]

Yep they were all within two thousandths of a volt of each other, 3.290v - 3.292v, I thought that was pretty good. So the balancer won't have much work to do yet.

After seeing some croc clips on a balancer on a thread round here recently I cribbed the idea and ordered a bunch off ebay so I have more soldering to do now Can just clip onto the busbars then, nice and easy.

That would be Nowty's set up. Excellent, you're nearly there!

Actually, my main balancer connection uses brass ring terminals like these which I would recommend, 5mm or 6mm should fit,
https://www.ebay.co.uk/itm/354243757975 ... BM3u6kre1g



My croc clips connectors are for parallel cell connectors, connecting several other batteries together in parallel to pimp off the single balancer which you don't need. As you have them in a vertical stack I would worry if they accidently came off and touched another bare bus bar.

[Jinx]

If your nervous putting in a link then stick your meter across one of the cells, then move the probe from the already connected terminal across the terminals to be linked, then move the probe you didn’t move first time across the other cell.

You obviously see cell voltage, then zero, then cell voltage. Sounds complicated written but it’s a two second job, proves the meter, the contacts you have made and that it’s safe to insert. It’s how I do it on MW capable batteries.

[Joeboy]

If your nervous putting in a link then stick your meter across one of the cells, then move the probe from the already connected terminal across the terminals to be linked, then move the probe you didn’t move first time across the other cell.

You obviously see cell voltage, then zero, then cell voltage. Sounds complicated written but it’s a two second job, proves the meter, the contacts you have made and that it’s safe to insert. It’s how I do it on MW capable batteries.

Sounds good, I will remember that when it is my turn. Thank you.

[Caesium]

Well thats made a royal mess of my nice neat battery stack



But its all connected and still no explosions. Just the one orange LED on it which I guess means power. I could try applying a small surplus voltage to one of the cells and see if it balances it back out, but otherwise I've no idea if its working yet, it has no balancing to do

[nowty]

Well thats made a royal mess of my nice neat battery stack



But its all connected and still no explosions. Just the one orange LED on it which I guess means power. I could try applying a small surplus voltage to one of the cells and see if it balances it back out, but otherwise I've no idea if its working yet, it has no balancing to do

That was quick, I thought you still had to order it.
Bet your happy now, I'm sure it's working fine.

I tested mine by shorting a cell with a 0.5 ohm resistor to instantly lower its voltage in the circuit.
https://camelot-forum.co.uk/phpBB3/view ... =10#p13028

[Joeboy]

Well thats made a royal mess of my nice neat battery stack



But its all connected and still no explosions. Just the one orange LED on it which I guess means power. I could try applying a small surplus voltage to one of the cells and see if it balances it back out, but otherwise I've no idea if its working yet, it has no balancing to do

Great to see well done indeed!
When are you making THE connections?

[Andy]

First change is that the 200Ah won't do the job. Don't have DOD I am looking to match in the Pylontechs.
Now looking at Eve LF280 batteries 3.2V 280Ah capacity across the stack and a 90% DOD at 6,000 cycle lifespan.

How did you do the DOD comparison? I haven't got my Pylontech yet but am already wondering how to extend them. plenty of room in the new shed and I will have a 1000A busbar to play with.

[Joeboy]

First change is that the 200Ah won't do the job. Don't have DOD I am looking to match in the Pylontechs.
Now looking at Eve LF280 batteries 3.2V 280Ah capacity across the stack and a 90% DOD at 6,000 cycle lifespan.

How did you do the DOD comparison? I haven't got my Pylontech yet but am already wondering how to extend them. plenty of room in the new shed and I will have a 1000A busbar to play with.

Damn good question Andy and without the sheets to hand I can only say that the lowest voltage acceptable on the LF280's was below my 90% dod I run my pylontechs to so not a problem. I will come back with figures later.

[nowty]

First change is that the 200Ah won't do the job. Don't have DOD I am looking to match in the Pylontechs.
Now looking at Eve LF280 batteries 3.2V 280Ah capacity across the stack and a 90% DOD at 6,000 cycle lifespan.

How did you do the DOD comparison? I haven't got my Pylontech yet but am already wondering how to extend them. plenty of room in the new shed and I will have a 1000A busbar to play with.

Damn good question Andy and without the sheets to hand I can only say that the lowest voltage acceptable on the LF280's was below my 90% dod I run my pylontechs to so not a problem. I will come back with figures later.

This is my cheat sheet.

[Joeboy]

How did you do the DOD comparison? I haven't got my Pylontech yet but am already wondering how to extend them. plenty of room in the new shed and I will have a 1000A busbar to play with.

Damn good question Andy and without the sheets to hand I can only say that the lowest voltage acceptable on the LF280's was below my 90% dod I run my pylontechs to so not a problem. I will come back with figures later.

This is my cheat sheet.

3.65v to 2.5v max charge/discharge voltage per cell pack on the LF280's. Both upper and lower values are outside of Pylontech operating parameters. Although if you are operating US2000C with a 95% discharge you'll need to confirm their lowest voltage for peace of mind. Nowtys cheat sheet will be damn close.