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the actual voltage was around 3.59.. because, as I said, the voltmeter on the charger is showing little bit more ... it's just not precise.. when I measue the voltage on the charger it's around 3.59 and there is couple of mV on the wires from charger to battery I disconnected the charger and left the cells in parallel for over 8 hours now.. the voltage now is 3.500V - 3.501V, but the deviation of 0.001 volt is probably because of the instrument I'm using (poor battery in it and very bad test leads/wires - its UT61E btw) Is this OK, expected ?

I have changed my wires for parallel/balance charging to copper strips and that has changed the current quite a lot.. finally my weak charger can give full current (10.2A) and go into constant current mode.. previously I had just wrapped and torqued regular electrical solid core wire around the posts ..and the resistance was too large so I was getting only around 8A .. so now I don't have to worry about voltage drop on the wires because it has almost none.. <0.001V on the wire to the charger and 0V on the copper strips Yesterday it was charging at 3.47V, the whole day.. for a long time the voltage didn't change.. and during the evening, in just couple of hours the voltage raised from 3.47V to 3.58V .. and now(few hours later) its still in CC mode at 3.65V and I expect to see transition to CV mode soon (voltmeter on the charger is showing a little bit more than it actually is).. is this normal? Is this that flat part of the curve transitioning to vertical part ? ___ edit: I just watched this video and I think this is my answer .. when I compensate for voltage drop in wires from the charger and the fact that my charger voltmeter is not precise

52°C ??? 🫠 I know this is South African forum.. are you from there also ? Actually I don't know how I ended up on this forum.. I guess while I was googling, this forum came up a lot, so I decided to join 😁 For me it's strange to think that south half of the world celebrates new year in the summer and have the longest day of the year in December ..and I am talking about how I'm afraid that my batteries will be damaged around 0°C while you have 52°C 😅 I know this is off-topic but it's interesting btw, I also think in "12V math" all the time, so no problem 😆

I got to around 3.45 for most of the cells except for that last 16th cell, which got to over-voltage protection and turned off the charging.. now I am slow balancing at around 8A again so now this one cell got to more than 3.6V couple of times and sometimes even to 3.7 for few seconds.. did this damage this cell maybe ? In the app there is this parameter called "overvoltage release delay" and I misinterpreted it and set it to 10sec.. and by default it is set to 2sec .. you can see a screenshot of my settings couple of posts ago

I have increased the current to 30A

Why less with the BMS? You mean to 3.45 while in series(with BMS) and then to 3.6 when top balancing in paralel?

Thank you all for help.. I'm home now, and took the battery with me.. looks like I'll have to use lead-acid for few more weeks there .. good thinking for not taking those 200kg batteries out of the basement because my back would say "no" if I had to carry them down there again 🤣 They have been balancing (passive I guess, through the BMS) whole day today, while I was reconnecting my lead-acid back and traveling home.. and they are a bit closer to each other now.. when the BMS stops charging I will connect them in parallel again and top balance with my slow charger I'm charging now with 20A.. Should I go higher? So, should I go to 3.6 or 3.625, 3.65V ?

It won't charge.. I guess because of the 8th and 9th cell are below 2.7V

Ok.. I will try that .. Now the cells are all at different voltage because I used them during the night and early morning..I have no power here other than this But the cells were at the same voltage before the first charge.. within 1mV..so I don't know how it will help

Hy all.. I have connected the battery to the inverter.. And I have a problem

Where are you located? I don't know the answer.. in fact, I don't really understand what exactly are you asking? Are you saying that the City limits your power production you are pushing into the grid? What is "CB" ? I'm just interested

Still charging around 8A.. this will take days.. 🤢 .. I'm thinking again about connecting the cells in series(with or without BMS ?), charging it with a solar inverter-charger(5.5kW) over the grid, to almost full.. and then again connecting it parallel like it is now, and charge/balance to full. Also, in last few weeks I started working on quite a few Li-ion packs.. for scooters and bicycles .. so I may invest in a charger/load tester like Steve87 has.. or something similar.. I found one in EU for around 275€ with shipping .. still seems a bit expensive, but even on aliexpress I can't find it cheaper.. I think this one is a pretty good one.. 40A, PC software, etc https://batteryfinds.com/product/zketech-ebc-a40l-large-current-lithium-battery-capacity-tester/ Can somebody recommend something else? Preferably cheaper ___ I bought cheap plastic box with a lid.. and lined it with fire retardant styrofoam.. this should help contain some heath during winter so it doesn't go under 0 deg C ..in summer, I can always take the battery out. side panels are shorter because compression fixture can't fit otherwise __ Also, I made a simple 3D printed brackets for mounting the BMS: here is the file.. it's a spinoff of another bracket uploaded on thingaverse JBD_BMS_Bracket.stl

I have finally connected the charger.. I have compressed it by feel with hand.. and I'm done with compressing.. as many say it is not worth the effort.. If I ever build another battery I will just compress by feel again I returned the big torque wrench and bought a smaller one, for bicycles.. still not low enough torque range.. this one is 2-20Nm +-4%.. but at least I can torque down the terminals and busbars now 😁 I connected all cells in parallel with household installation wire.. solid core, I think 2.5mm.. no wires are touching each other.. and the charger poles are on the opposite sides as you suggested And from the start it was about 3A only.. my shitty TEMU voltage source came with very bad wires.. there is around 0.12V on each wire.. so the actual voltage applied to the battery is only around 3.3V.. it will go up as current gets lower.. I hope this will be OK.. I don't think I can damage the battery this way.. I don't want to increase the voltage on the charger to compensate for drop in wires __ edit: I realize now how stupidly long it would take to charge the battery at 10W.. I'm thinking 20 days or so.. I'm in search for better wires right now __ 2nd edit: new wires.. charging at 8A now

I bought a torque wrench today.. but I just realized how little torque is actually needed for 3000N of force.. spread out on 4 bolts.. one can easily over tighten it just with a hand screwdriver.. and I now have a wrench used for tightening car wheels and such😅 .. minimal torque setting is 28 Nm 😅 Couple of posts ago we calculated it needs to be just 0.6 Nm for 4x 4mm bolts.. now I have 6 bolts, that is 0.4 Nm.. is this correct ? It doesn't make much sense to me.. that is only 0.04kg=40g on 1m .. one can easily tighten this with fingers.. am I supposed to divide 3000N by 6, for six bolts ,,or each bolt must press with 3000N ? 40g is 2 packs of cigarettes 🤔???