Not sure if I got everything you said. First make a 10s pack by connecting cell 5 positive to cell 6 negative. Than you solder the charge leads negative to cell 1 negative and positive to cell 10 positive. Than you start soldering the balance leads 1-10 starting at the cell 1 positive or cell two negative and so on till cell 10 positive which should be balance wire 10.
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youād need a dc regulator in between dc power and your battery to adjust voltage. not sure if these ac-dc power supplies are cc/cv.
i use a dps5015 - it goes up to 50v @ 15a. not totally useful for 12s since it needs to be about 50.7v to kick into balance charge.
i think it started with jehu garcia copying teslaās cell fusing. butā¦i donāt think it makes sense in esk8s with low P count and high amp draw. in a massive pack, losing a cell or two isnāt going to have a massive effect. ie, tesla packs are 72p, so lose a cell in there - now itās 71p, doubt itāll have a huge impact. and iām sure they have pack monitoring to report lost cells.
weāre running 3,4,5p cells in esk8s, lose a cell there and entire pack will be out of balance within a cycle.
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With the dps5015 what power supply is needed? I imagine must be capable of high amps. Some of the cheap supplies are voltage adjustable from all the way down to zero up while most just lurk around their maxā¦whatās a SOLID supply that is already adjustable? I have stacks of broken ones. From what I hear while they may have a stated current that it will put out continuously its best to somehow get inside and reduce the current output. Iād do that if I knew how. In fact I have two supplies that have an extremely adjustable voltage with led and knob that are broken but would get another and mod it if possible. Theyāre cheap
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Specs say range of 6-60V typically you want something close to the target output voltage so it isnāt needing to boost or drop (buck) the voltage up or down by too much. Like you said figuring out amps is the key thing. Way I work this out takes some fudging but basically if you know the output wattage because you know the max voltage of the batteries when fully charged and know the max C rating you want to use for charging (usually 1C) then you can work out output wattage and you know the input wattage needs to be higher than this since there will be some loss in the components in the charger/balancing mechanism.
So say you have 10S you want 42V max charge, say you want to charge at 5A then you need at least 5*42 = 210W (to add some fudge factor add 10% or so on this call it 230W say 20W used for electronics or bled off as heat). If you have a AC->DC transformer that puts out DC at 50V it would need to supply at least 230W/50V = 4.6A
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Thanks, this was the exact response I was looking for! Really appreciate all the help Andy 
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https://eu.nkon.nl/sk/k/30q.pdf page 14, short circuit with 10mohm test results. Lots of other cool tests including a crush test!
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With high amps? will be $$$$ and huge. Best bet is a switchmode lab PSU, I think.
This is probably the most reasonable high amp thing, 60v 11a. These Gopherts are reasonable quality switch mode supplies. EEVblog seems okay with them for the most part. This one has a 110v option, which had been hard to find.
60v 7a version ā I have one, seems okay.
If you run any of these cheaper things at max all the time, theyāll probably pop without additional cooling.
@thisguyhere I use DPS8005 for charging 13s, with a 60v PSU
Actually to charge 13s I use a few different setups:
- Korad KA6003P (linear supply, HEAVY)
- DPS8005 with 60v psu
- Gophert CPS-6011
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I missed ur post and got one of these. meanwell HLG-480H-54A Does nine amps at just over fifty volts. Voltage a bit adjustable and no fan. good price at 154 w shipping on amazon for what I expect will last. Iām definitely mounting this one to the ceiling with long wires. I drop these things constantly and likely a reason theyāre breaking.
Those 30q tests thoughā¦Iāve come to be suspicious of how none ever go in runaway with the shorting test. Iād heard as an explanation that if many cells are together and shorted the heat would be more and enough to send into fire but otherwise it wonāt. And thatās what this data shows. Personal experience of two people showed a single 30q going to flame in moments of shorting
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There is also a adjustable cc/cv charger on aliexpress. 3000watt 0-90v 0-30A. Only thing: 200 euro
https://s.click.aliexpress.com/e/cDUvah3E
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Probably the way to go for longevity. ā¦thing is capable of way more than needed and will likely stay cool. Too late for me dare I say this time.
The waveform out of these would be nice to see and I read they arenāt that clean even out of mean-well and that has negative consequences on the battery.
Long wires will have a pretty big voltage drop at high amps. Use thick stuff! And check voltage at the charge port with a multimeter while charging to see how big the drop is.
Those HLGs feel nice after all those no-name PSUs, right?
And sadly 220v
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Theyāre for sure nicer with having no fan at least. Iāve seen them around. Thought they were more expensive, or this is a new model actually and given everything think itās worth it.
Iāll hook my wattsup watt meter on the end as usual to see watts up and v. Too scary otherwise.
Hehe indeed. I am so happy we have 230v here in Belgium.
Just got a 500W LED driver power supply (24V) for AC->DC for my balance charger, was previously using a bench power supply just to get the DC output and wanted to move that to my bench for actual electronics work stuff, but havenāt had enough time with the new supply to give it a + or - either way. So far it powers up but will let you all know once Iāve used it at least a few times if I run into issues. Fan noise is pretty high but have heard of people modding to add a thermally triggered switch to just kick the fan on when itās getting hot inside, for now just unplugging when Iām not using also could use an e-stop switch I have sitting around maybe.
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Need yāallās help and opinionsā¦
I got a bunch of salvaged cells that are all sorts of fucked up (weld damage and torn wrapping) from a guy on the old forum, and Iām using a cell holder system. Before I can use the cells I need to clean the ends of them and rewrap them
I have 48 30Q cells and just enough heat shrink tubes and fish paper ends to treat them
I used a Dremel on a test cell and I can face both ends to a relatively smooth ground surface with a stone wheel attachment but it destroys the existing wrap. Is this acceptable to use in a holder?
Also how do I get the shrink wrap to wrap if I donāt have a heat gun? Iāve got an oven and a MAPP gas torch, I was thinking the oven would be the better option but Iām not sure what temperature to use
Please donāt tell me to spend more on parts, Iām gonna do this anyways so Iād like of you can help me no kill myself in the process. I donāt encourage this behavior to anyone else, do as I say and not as I do and what not
Thanks!
Do you have a hair dryer? Iāve re-wrapped cells and a hair dryer does great with the wraps. That dremeled top looks good imo.
Are you capacity/IR testing them before putting them to use? I use the litokala li-500 for testing my salvaged cells and repakr to match cells into P groups: https://secondlifestorage.com/repackr.php
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Lol the Littokitas are the cells in trying to replace, 10s2p to 12s4p 
Will try the hair dryer, thanks!
I donāt have any way to test these cells but they have the right lables on them, I bought a pack from someone who was leaving the hobby but the pack literally fell apart in transitā¦shitty pack and shitty shipping but supposedly they are legit, the guy says he used it like 10 times and got the cells from IMR
Iām just rebuilding the pack so it isnāt a fire hazard
My babies
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Mmm! Cells.
I meant the litokala li-500 charger, itās great for testing cells and cheap on Amazon. https://www.amazon.com/d/Power-Tool-Battery-Chargers/LiitoKala-Lii-500-Battery-charger-capacity/B073R7VCMZ
If he got the cells from IMR, I think youāre good. I donāt know the details of the markings but they are supposed to have markings like that under the wrap.
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These paper dime rolls fit 18650 almost perfectly, might save some time.
Itās correct and cheap but will take for-fucking-ever to cycle test with just one 4 cell charger. 
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