Help Mixing pouch cells

[Lucifer]

Depends on what HVC and LVC it has for each of the cell groups it monitors. As long as the LVC is the same or higher than the cells you're using, and the HVC is the same or lower than the cells you're using, it is safe enought to use....except:

It's not uncommon for the BMS to be what kills cells, by having a balance shunt in one or more channels fail stuck on, so ti just keeps draining these groups all the time, utnil they finally are below empty or even 0V.

There are some tests youc an do depending on what parts you can access ont eh BMS. If you can post a pic of both sides of ti we can draw arrows to points you can test and what to set the meter to and what you'd expect for good or bad results.

Photos as requested, I got several of these from the litho batteries I picked up from someone who was going to build a power wall and gave up on it.

On that subject several of these LI-PO packs are obviously are "Spares Parts" but useful. However Three of them, all identical, visually look perfect, no puffed cells or visual imperfections, and they appear fully charged, (little over 36 v but have been on a shelf for ages here, and god knows how long before. SO I WAS THINKING, after testing my 18650 battery. I could litterally use the lead I made to plug that into the bike to put these straight on the bike and see what happens, (Not a lot to loose, who knows I might have a couple of perfect batteries in the pile). What do you think..... I'll be careful and keep an eye on them , short trips round block check temp, and voltages.

 

[Lucifer]

I do...I learned vacuum tubes (valves) in ham radio as a kid ffrom a neighbor a ways down the gravel road we lived on in farm country...later i learned solidstate stuff at school, but I'm no engineer.

That sounds cool. I was bought up in the country as well.

 

[Lucifer]

Photos as requested, I got several of these from the litho batteries I picked up from someone who was going to build a power wall and gave up on it.

On that subject several of these LI-PO packs are obviously are "Spares Parts" but useful. However Three of them, all identical, visually look perfect, no puffed cells or visual imperfections, and they appear fully charged, (little over 36 v but have been on a shelf for ages here, and god knows how long before. SO I WAS THINKING, after testing my 18650 battery. I could litterally use the lead I made to plug that into the bike to put these straight on the bike and see what happens, (Not a lot to loose, who knows I might have a couple of perfect batteries in the pile). What do you think..... I'll be careful and keep an eye on them , short trips round block check temp, and voltages.

I know you cant tell anything by just looking but I have four of these packs, all that look ok, and have heald full charge for ..... AGES.

They are the ones I was thinking of just sticking on the bike and trying. Any comments? OH it was me who wrote OK on them, based on the fact that they looked OK, and had held full charge a long time, And I did also check each pair of pouch cells, and they are in balance at the moment.

RFC?

 

[999zip999]

It looks like you have a spot welder is this true ?
My first pack was a commercially made ping battery and it's BMS had one bleed resistor stick on as aw said and drain one of the 16 parallel cell groups to zero. After that I ran my packs with just balance wires and that cell meter I showed you in the picture. My packs are 20 ah so big enough that I have range when using so I can monitor the pack for lvc. The smaller the pack the harder it is to self monitor or to be the human BMS. With no BMS you are solely responsible for hvc and lvc. So it's time consuming and not for everyone.
I do have a new pack 72 volt 24ah with BT BMS and like it I think they've got most the problems out of the BMS since my first pack 14 years ago. So that's what I'd use again would be a Bluetooth BMS.
I can't really tell what shorted on your pack but every one of those tiny sense wires or balance wires for the BMS is hot. And kapon tape is needed Florida Governor to protect the wires from Laying directly on the nickel strips. What I'm saying is don't lay the BMS balancing wires directly on the nickel strips.
A.W can you find the Dark Angle battery build thread ?

 

[Lucifer]

It looks like you have a spot welder is this true ?
My first pack was a commercially made ping battery and it's BMS had one bleed resistor stick on as aw said and drain one of the 16 parallel cell groups to zero. After that I ran my packs with just balance wires and that cell meter I showed you in the picture. My packs are 20 ah so big enough that I have range when using so I can monitor the pack for lvc. The smaller the pack the harder it is to self monitor or to be the human BMS. With no BMS you are solely responsible for hvc and lvc. So it's time consuming and not for everyone.
I do have a new pack 72 volt 24ah with BT BMS and like it I think they've got most the problems out of the BMS since my first pack 14 years ago. So that's what I'd use again would be a Bluetooth BMS.
I can't really tell what shorted on your pack but every one of those tiny sense wires or balance wires for the BMS is hot. And kapon tape is needed Florida Governor to protect the wires from Laying directly on the nickel strips. What I'm saying is don't lay the BMS balancing wires directly on the nickel strips.
A.W can you find the Dark Angle battery build thread ?

Hi there.

Yes got a spot welder, for info I bought a cheap one on e-bay, became ill so it sat in box for a year, got better and googled using it. Found while it was dirt cheap had a design fault that was easily fixed when it blew. decided not to wait for that so fixed it adding the extra cap before that happened. Also found that using two batteries, one for the control circuit and one for the actual weld mad this thing much better (stop the drop to the batt when actually welding). Its now awsome thousands of welds in no time cosy under £20. IF YOU WANT THE DETAILS, ill provide links to the welder, and to the mods that turn it from cheap crap into awesome.

Back to my pack, I'm fairly certain which wire caused the problem, I had already fixed all balance wires in place wasn't them. but there were 3 longer wires attached (P+ P- +ve), even tho the ends of the three wires (+ve P-ve and- Charge) were just cut (not stripped) I had insulated them, but the tape had come off one and that one was exactly the right length to have caused the problem. As I immediately lifted the pack (Run like ****) I immediately removed the short, and it looks like I got away with it.

I looked at bluetooth BMS after your previous suggestion, they are great but expensive, being a pensioner I'm on a tight budget, I made a note for future use, but atm I'm trying to do this with all the stuff I have been given or purchased for peanuts. (in an ideal world..... etc). I love learning about all this but I'm seriously brassic atm.


Keith

 

[999zip999]

If I did use a cheap BMS I would still have an extra set of balance wires so I could check with a cheap 8s cellmeter get the one that can do1-6 . The reason IThis is for fast checking and can your imax to charge. Oh your charger needs pos and ned plus balance leads ? As mine charge's thru the balance wires only..

 

[Lucifer]

If I did use a cheap BMS I would still have an extra set of balance wires so I could check with a cheap 8s cellmeter get the one that can do1-6 . The reason IThis is for fast checking and can your imax to charge. Oh your charger needs pos and ned plus balance leads ? As mine charge's thru the balance wires only..

Hi again, the BMS i'm using are not exactly cheap (70 amp ) but I got them some time ago from someone building a power wall, and had given up on it and just wanted rid of the stuff, so I got them as part of a package, with very little money changing hands. I suspect they were expensive in fact. That said I did buy some "battery metering gadgets" for want of a better word, that were cheap, and you connect them just like a bms (in parallel to it, in fact) and these show you what each group of cells is doing. TBH this has already taken Sooooooo much longer than expected, FIRST I just want to get to the point where the ******* bike will get me to the local shops and back. That said, once I get to that point, then one of my first improvements will be adding these battery monitoring gadgets I have already purchased, Once one is fitted I can easily unplug it and plug anything else into the multiway connector instead.

Keith

 

[Lucifer]

It looks like you have a spot welder is this true ?
My first pack was a commercially made ping battery and it's BMS had one bleed resistor stick on as aw said and drain one of the 16 parallel cell groups to zero. After that I ran my packs with just balance wires and that cell meter I showed you in the picture. My packs are 20 ah so big enough that I have range when using so I can monitor the pack for lvc. The smaller the pack the harder it is to self monitor or to be the human BMS. With no BMS you are solely responsible for hvc and lvc. So it's time consuming and not for everyone.
I do have a new pack 72 volt 24ah with BT BMS and like it I think they've got most the problems out of the BMS since my first pack 14 years ago. So that's what I'd use again would be a Bluetooth BMS.
I can't really tell what shorted on your pack but every one of those tiny sense wires or balance wires for the BMS is hot. And kapon tape is needed Florida Governor to protect the wires from Laying directly on the nickel strips. What I'm saying is don't lay the BMS balancing wires directly on the nickel strips.
A.W can you find the Dark Angle battery build thread ?

Hi

Replying to the same post again, just read it again. (been a long hard day, not bike related). Saw more to reply to. Your batteries sound better than mine but I expect this to be 15Ah atm.

Ironically, I was actually in the process of fitting a couple of layers of foam rubber, between the balance wires and the nickle srtips when the smoke suddenly appeared, (it was the foam rubber that was smoking)

Have not yet found the Dark Angle thread, I did have a quick look, I didn't see it (But I'm also new to using a forum) but again TBH I have been fitting this entire project into an already stupidly busy life, and have spent a considerable amount of time, searching for "Absolutely Essential", as oppose to "OH! that looks interesting", So I have about million things I want to come back to once I complete the initial learning curve, which has been fascinating, but at least ten times as much as I expected. As I said in another post to amberwolf from memory "Build a battery", how hard can it be? lol....... I thought this would take a few hours LOL To be fair once I finally started putting these cells together, it did only take a couple of hours, but god knows how many hours of research and learning before using doing my first spot weld. LOL

Thanks again for all your help. everyone who has contacted me has been so helpful . I Would of prob burnt the house down without all the support and info,

Keith

 

[Lucifer]

Hi there.

Yes got a spot welder, for info I bought a cheap one on e-bay, became ill so it sat in box for a year, got better and googled using it. Found while it was dirt cheap had a design fault that was easily fixed when it blew. decided not to wait for that so fixed it adding the extra cap before that happened. Also found that using two batteries, one for the control circuit and one for the actual weld mad this thing much better (stop the drop to the batt when actually welding). Its now awsome thousands of welds in no time cosy under £20. IF YOU WANT THE DETAILS, ill provide links to the welder, and to the mods that turn it from cheap crap into awesome.

Back to my pack, I'm fairly certain which wire caused the problem, I had already fixed all balance wires in place wasn't them. but there were 3 longer wires attached (P+ P- +ve), even tho the ends of the three wires (+ve P-ve and- Charge) were just cut (not stripped) I had insulated them, but the tape had come off one and that one was exactly the right length to have caused the problem. As I immediately lifted the pack (Run like ****) I immediately removed the short, and it looks like I got away with it.

I looked at bluetooth BMS after your previous suggestion, they are great but expensive, being a pensioner I'm on a tight budget, I made a note for future use, but atm I'm trying to do this with all the stuff I have been given or purchased for peanuts. (in an ideal world..... etc). I love learning about all this but I'm seriously brassic atm.


Keith

On the spot welder I actually purchased looks like that one has gone up a bit now £26 pounds. but looks like some other very similar cheaper ones are now available for as little as £11, these were not available when I bought mine as I would have tried one of the cheaper ones. They probably need the same mods though (unless they have removed the design floor, when they ripped off the design LOL), you would have to google that yourself if you went for one of them. I can link you to exactly what you need if you bought the same one I bought. (Just fitting one extra capacitor, and using two batteries, so change how its connected, (the latter being v easy). Some people also reinforce a couple of tracks on the board, but if you use the two battery setup, you don't have to do that, I didn't, and mine is fine, it just knocked out about 1500 welds in one hit no problem at all.

Keith.

Keith

 

[999zip999]

DrkAngel

endless-sphere.com

Don't know how to work with endless spear new format.
Google DrkAngel homemade battery packs.
or A W could paste the link
I don't know how to put the link I want into this thread
Dark Angel has a bunch of threads on batteries tools and stuff can't believe no one else would put his Link in here as I can figure it out.

Homemade Battery Packs

Index - January 2022 Updating Tools and Parts LiPo vs SLA 18650 info 18650 cell specs by manufacturer 18650 chemistry by model designation Recent 12.8V 1.280kWh portable power w/inverter FIRE - not Lithium! Resurrecting "dead" ( extreme low voltage Lithium cells ? ) Max Life and...

endless-sphere.com

 

[Lucifer]

NEWS UPDATE !!!

Tried my DIY 36v battery, 0-30 MPH no problem, twist and go no peddling, with the brakes still stiff and binding, Looks VERY promising. . So I'll get the lock of the 24 v bike, do some mechanical repairs and adjustments, then some runs to local shops etc, If all that goes to plan, (and I'm sure it will). Next bigger test test will be to the Scout Hall about 4 miles uphill, all the way (but at least it's downhill coming back, in case there is a problem I can turn round and more or less freewheel all the way back), Ill measure the cells after each trip, if it stays in balance Ill connect one of the battery monitor gadgets I already have then case it.

Then once I'm sure I have a working bike so I can actually get about back to the original pouch cells, re read everything everyone has already sent me and every post, then start again building the new pouch battery that I started out trying to do.

First Ill try the 4 pouch cell batteries from the pile of "doner batteries" to see if they actually work, shouldn't be any questions there, either they will work fine (which I realise is probably wishful thinking but they look perfect and measure perfect, so gotta be worth a shot) Failing that they go back into my spare parts n components and at least I will be able to start from scratch and build a couple by testing each component, select the best, then build a couple from the parts (as I have about 10 in total..... should obviously be able to build a couple).

However if to have to take that route, I will first go back to the original heavy duty 36v battery that came with the bike. It had 2 fried cells, so expect some questions and photos as to replacing them firstly if possible from my "rather large growing" selection of spares parts, failing that sourcing two new cells to match the rest.
Thank you one and all for all your help, suggestions and contributions,

DrkAngel

endless-sphere.com

How ironic, I was just looking for it again and was trying to PM him to ask for a link, for some reason I was looking for Dark Angel (doesn't exist) so tried Dark Angle in case also nope. My mind must have automatically converted DRK to Dark, without me realising, all down hill after that, (but easier to peddle) LOL.

 

[Lucifer]

NEWS UPDATE !!!

Tried my DIY 36v battery, 0-30 MPH no problem, twist and go no peddling, with the brakes still stiff and binding, Looks VERY promising. . So I'll get the lock of the 24 v bike, do some mechanical repairs and adjustments, then some runs to local shops etc, If all that goes to plan, (and I'm sure it will). Next bigger test test will be to the Scout Hall about 4 miles uphill, all the way (but at least it's downhill coming back, in case there is a problem I can turn round and more or less freewheel all the way back), Ill measure the cells after each trip, if it stays in balance Ill connect one of the battery monitor gadgets I already have then case it.

Then once I'm sure I have a working bike so I can actually get about back to the original pouch cells, re read everything everyone has already sent me and every post, then start again building the new pouch battery that I started out trying to do.

First Ill try the 4 pouch cell batteries from the pile of "doner batteries" to see if they actually work, shouldn't be any questions there, either they will work fine (which I realise is probably wishful thinking but they look perfect and measure perfect, so gotta be worth a shot) Failing that they go back into my spare parts n components and at least I will be able to start from scratch and build a couple by testing each component, select the best, then build a couple from the parts (as I have about 10 in total..... should obviously be able to build a couple).

However if to have to take that route, I will first go back to the original heavy duty 36v battery that came with the bike. It had 2 fried cells, so expect some questions and photos as to replacing them firstly if possible from my "rather large growing" selection of spares parts, failing that sourcing two new cells to match the rest.
Thank you one and all for all your help, suggestions and contributions,

How ironic, I was just looking for it again and was trying to PM him to ask for a link, for some reason I was looking for Dark Angel (doesn't exist) so tried Dark Angle in case also nope. My mind must have automatically converted DRK to Dark, without me realising, all down hill after that, (but easier to peddle) LOL.

Are still some work to do then, that links me to him and to a list of 5,300 different post. But now I got his name right I'll pm him and ask for a link to his "Battery Build"

Thanks K

 

[999zip999]

Take it easy with the hills that's how you burn up a motor and controller first kind of do the flats and put your hand on the motor of the controller to see if it gets hot then you can do a mile hill and see if it gets hot before you do the four Mile Hill. Put your hand on it it was too hot to touch it'll melt wires.
Yeah I'm 65 and I knew how to work this in this spear forum but it's been changed two or three months ago it's a headache and a relief easier to send pictures

I gave you a link look back one or two posts of mine.
Homemade battery packs.

 

[Lucifer]

Take it easy with the hills that's how you burn up a motor and controller first kind of do the flats and put your hand on the motor of the controller to see if it gets hot then you can do a mile hill and see if it gets hot before you do the four Mile Hill. Put your hand on it it was too hot to touch it'll melt wires.
Yeah I'm 65 and I knew how to work this in this spear forum but it's been changed two or three months ago it's a headache and a relief easier to send pictures

I gave you a link look back one or two posts of mine.
Homemade battery packs.

Then I'll find it because while I have been constantly focussed on my immediate problem, of getting something working. Now I'm almost there, I was going to go back through every single post. OH on that they don't delete them do they, no time limit or anything, only just thought of that possibility.

Thanks for the help and the tips.

The hill isn't that steep btw, but being 4 miles long with a bad ankle on one side and hip on the other side, you certainly notice it peddling LOL. coming back even without power is easy a long slow decent.

Btw this bike (the 36V one) was a friends who used to use it every day to do a 30 mile journey across london and then use it to come home, until he changed jobs, then he just left it unused for a long time, and killed a couple of cells in the battery, so I know the motor and controller "Should" not be a problem. When I first got it I did some immediate maintenance as things were beginning to get seized, so i freed everything of enough to stop anything getting totally screwed up, but if it was my daily ride, everything would be in better shape than it is atm.

I took it out again today, did about four miles in a circular route mainly on the flat but half was the same gradient as the scout hut (in fact part of the route) as an intermediate test. Nothing got warm, and when back immediately metered the battery, still all balanced, no voltage drop at all yet. Next time will put hand on motor to check if that gets warm. Still have not lubricated and made the wheels spin as free as they should, (bike hasn't moved for years) they are not that bad, but def could do with bit of attention (for now decided the extra work would make a better test TBH). Also brakes were rubbing a bit, so just slackened them off for now, probably the cables need wd40, or better still silicon lube (fantastic stuff).

On the Forum, I don't know any different, only recently discovered it, a couple of weeks ago, I could not even find my own post LOL, took a week before I spotted the Bell that tells me someone has replied to one of my post. But getting the hang of all the basic stuff and comfortable with all that now. such as attach pix, links, smilies, have used all them. It's all very cool.

When I get time, I'll explore it further, I have had a very quick look at a few dif sections.

Keith

 

[Lucifer]

Take it easy with the hills that's how you burn up a motor and controller first kind of do the flats and put your hand on the motor of the controller to see if it gets hot then you can do a mile hill and see if it gets hot before you do the four Mile Hill. Put your hand on it it was too hot to touch it'll melt wires.
Yeah I'm 65 and I knew how to work this in this spear forum but it's been changed two or three months ago it's a headache and a relief easier to send pictures

I gave you a link look back one or two posts of mine.
Homemade battery packs.

Ah I missed the second link (two in one post), I followed the first link, (took me to all his post.... thousands of them) I saw the second one but mistook it for some general info on cells, so as I was past that point on this build, I didn't immediately follow it up, decided to look at it later before starting the next build.

Anyway I have it now, I'll still prob leave till the next build as this battery was in theory finished before that post, so assuming it continues to pass practical test, I'll case it up, and call this one done. As at least I will have a working bike.. Then Ill start over start over, see if I can make a better battery, or a better bike, god knows I have enough donor parts. So it will be essential reading at that point.

I might in fact look before that it's got me intrigued now, but whatever it says, I'll be reluctant to pull this battery apart, now I have got to this point of having something that works. I can always improve it later once I build a second better battery, I want to ensure that I always have at least one working battery ready to use.

Keith

 

[Lucifer]

DrkAngel

endless-sphere.com

Don't know how to work with endless spear new format.
Google DrkAngel homemade battery packs.
or A W could paste the link
I don't know how to put the link I want into this thread
Dark Angel has a bunch of threads on batteries tools and stuff can't believe no one else would put his Link in here as I can figure it out.

Homemade Battery Packs

Index - January 2022 Updating Tools and Parts LiPo vs SLA 18650 info 18650 cell specs by manufacturer 18650 chemistry by model designation Recent 12.8V 1.280kWh portable power w/inverter FIRE - not Lithium! Resurrecting "dead" ( extreme low voltage Lithium cells ? ) Max Life and...

endless-sphere.com

Couldn't resist so was going to start reading some bits. But when you mouseover a subject cursor turns into a hand, indicating I should click it to go to the article? I tried about 6 but all it does is take me back to the top of the page. Am I doing something wrong, or is it broke?

Keith

 

[Lucifer]

They have a comparison database, but I haven't used it. I almost always am just going there to get discharge curves and other data for various cells to post in people's threads where they are asking about whether that cell will work in their application (they don't usually know what cell they have, so I cant' often do this).



The green cell page doens't have any specs in it's table to compare to the purple one, so can't tell if they are the same.

The important thing isn't specifically the actual chemistry, but the voltage ranges they operate within. So fo the purple cell taht's 3.62v nominal (meaning average voltage near the middle of the total capacity usage), and 4.2v max (HVC), and 2.5v min (LVC). The green cell has no data there.

Going to the lygte-info.dk comparator

Battery test-review 18650 comparator

for
Samsung INR18650-29E (purple)
and
Sony SF US18650V (green)
also has no specification or voltage data for the green cell, so no comparison for matching htem up can be made.

It does give this chart showing the green cell is way smaller in capacity and doesn't handle loads as well as the purple, so it would take at least twice as many of those cells in parallel to make the same kind of pack as t he purple, if they were each their own separate pack.

View attachment 338024
and these are the pages for them

Test of Samsung INR18650-29E 2900mAh (Blue)

Test of Sony US18650V 1600mAh (Green)

showing the official specs in text and actual results in images below

View attachment 338020
Official specifications:

• Nominal Capacity: 2,850mAh (0.2C, 2.50V discharge)
• Typical Capacity: 2,850mAh (0.2C, 2.50V discharge)
• Minimum Capacity: 2,750mAh (0.2C, 2.50V discharge)
• Charging Voltage: 4.20 ± 0.05 V
• Nominal Voltage: 3.65V (0.2C discharge)
• Charging Method: CC-CV (constant voltage with limited current)
• Charging Current: Standard charge: 1,375mA
• Charging Time: Standard charge: 3hours
• Max. Charge Current: 2750mA (not for cyclelife)
• Max. Discharge Current: 2,750mAh (continuous discharge), 8250mAh (not for continuous discharge)
• Discharge Cut-off Voltage: 2.50V
• Cell Weight (max. (g): 48g
• Cell Dimension: Diameter(max.) : 18.40 mm, Height(max) : 65.00 mm,
• Operating Temperature: (Cell Surface Temperature) Charge: 0 to 45°C, Discharge: -20 to 60°C
• Storage Temperature: 1 year : -20~25°C, 3 months : -20~45°C. 1 month : -20~60°C

View attachment 338021
Official specifications:

• I could not find any.

Have only just had chance to really study this, the battery comparator is really useful, apart from anything else I have hundreds of mixed green cells, while they may not be much good to power the bike, I have always liked the idea of building a separate 12v battery for decent head lights, rear lights, indicators and stuff, plenty of cheap 12v stuf available for motorbikes. And this way I wouldn't be concerned about draining my actual battery. So that is definitely going to get used for that. I actually went to it, then realised you had done it for me. Thanks.

As I knew I had enough blue cells (all well tested and pretty identical) to build a battery and in the light of the above, I pressed ahead and built a battery completely out of them leaving the green cells out, less cells in total but less problematic and quicker, which for me was a massive plus, to get one working bike on the road ASAP. That battery appears "VERY GOOD" but is still being tested, I wont repeat that stuff here but its posted later in the thread. As are my immediate other plans.

In another post you mentioned or discussed overvolting very briefly. I came to the conclusion that the 24v bike is and probably always has been underpowered. But apart from that every mechanical part of that bike is perfect. For now I will be able to press on with all my other plans (hopefully wont need much help on any of that for a while). But in the evening I wanted to read up on overvolting the 24v bike, (as I suspect I'm going to end up with a few 36 v batteries, and I think its underpowered by design). I'm sure the motor will take it, but if these is a way to be sure that would be good.

You mentioned that controller wight well take the 36 V, obviously Ill get it out and see what value in on the components, that should give me a good idea. But I want to source as close as a direct replacement as poss before ov the bike, I wont buy it unless either its clear the orig isn't up to it, or it looks ok but I ruin the original one, be nice to have the replacement lined up.

So can you point me at a good beginners guide to over volting on the forum, so I have plenty of time to study it and consider it, before attacking it (which wont be for a while, but I thought i would do more study before jumping in at the deep end this time) LOL

keith

 

[999zip999]

Just don't discharge below 3.0 volts per cell.

 

[Lucifer]

Have only just had chance to really study this, the battery comparator is really useful, apart from anything else I have hundreds of mixed green cells, while they may not be much good to power the bike, I have always liked the idea of building a separate 12v battery for decent head lights, rear lights, indicators and stuff, plenty of cheap 12v stuf available for motorbikes. And this way I wouldn't be concerned about draining my actual battery. So that is definitely going to get used for that. I actually went to it, then realised you had done it for me. Thanks.

As I knew I had enough blue cells (all well tested and pretty identical) to build a battery and in the light of the above, I pressed ahead and built a battery completely out of them leaving the green cells out, less cells in total but less problematic and quicker, which for me was a massive plus, to get one working bike on the road ASAP. That battery appears "VERY GOOD" but is still being tested, I wont repeat that stuff here but its posted later in the thread. As are my immediate other plans.

In another post you mentioned or discussed overvolting very briefly. I came to the conclusion that the 24v bike is and probably always has been underpowered. But apart from that every mechanical part of that bike is perfect. For now I will be able to press on with all my other plans (hopefully wont need much help on any of that for a while). But in the evening I wanted to read up on overvolting the 24v bike, (as I suspect I'm going to end up with a few 36 v batteries, and I think its underpowered by design). I'm sure the motor will take it, but if these is a way to be sure that would be good.

You mentioned that controller wight well take the 36 V, obviously Ill get it out and see what value in on the components, that should give me a good idea. But I want to source as close as a direct replacement as poss before ov the bike, I wont buy it unless either its clear the orig isn't up to it, or it looks ok but I ruin the original one, be nice to have the replacement lined up.

So can you point me at a good beginners guide to over volting on the forum, so I have plenty of time to study it and consider it, before attacking it (which wont be for a while, but I thought i would do more study before jumping in at the deep end this time) LOL

keith

Just noticed I'm now 1 watt? Is that the number of post? Cos it says that under your name anyway, so thought it might be something else?

 

[calab]

Its your power level, its very low because of post count I assume. I think post counts dont add up in the Off Topic section but I cant be certain. Dont play the post count game, quality over quantity, or you can have both like some who go that extra mile to help others.

 

[Lucifer]

Its your power level, its very low because of post count I assume. I think post counts dont add up in the Off Topic section but I cant be certain. Dont play the post count game, quality over quantity, or you can have both like some who go that extra mile to help others.

Thanks I was just curious, I only joined about 2 weeks ago, didn't even notice it at first then I noticed it was changing, I suddenly remembered it used to say 10mw (which is obviously just starting off), so realised it was monitoring something.

 

[Lucifer]

Just don't discharge below 3.0 volts per cell.

You can buy box from china for under £10 that look exactly like 12v Sla battery boxes (in fact probably are) they come with nickle battery plates and 3 x 7 BMS, to get to 12v (or thereabouts), So I would think the BMS (even though obviously "BUDGET" would still do the same job and stop over discharging cells, shouldn't it?).

Even if not, these cells are of little if any value to me, and they would only be powering lights and accessories.

Keith

BTW did you see my other post to you, that all those drkangle links do not appear to work, I had another more determined attempt, could not get any to do anything, other than go to top of page, so pretty sure it's not me. Should I or someone more experienced report it to the forum (after confirming its actually broke LOL) ?

 

[999zip999]

It seems to be Frozen or maybe lost its threads I don't know why some of these disappear but he has a lot of good information dark Angel.
Hopefully a moderator can chime in and help as I didn't understand why I couldn't pick up his old threads?
Plus I'm looking at battery spot welders maybe you can start a thread on your spot welder and how you got it to work so well I see some blue to capacitor spot welders for under $90 able to weld 03 pure nickel.
Have you gotten rid of the batteries that are old or unusable ?

 

[Lucifer]

It seems to be Frozen or maybe lost its threads I don't know why some of these disappear but he has a lot of good information dark Angel.
Hopefully a moderator can chime in and help as I didn't understand why I couldn't pick up his old threads?
Plus I'm looking at battery spot welders maybe you can start a thread on your spot welder and how you got it to work so well I see some blue to capacitor spot welders for under $90 able to weld 03 pure nickel.
Have you gotten rid of the batteries that are old or unusable ?

Hi again. First do you want me to send you links to the spot welder

I have attached a couple of photos of the one I bought, done a couple of thousand welds so far no prob mine was about £20

BUT, apparently there is a well known design fault that's easily fixed by soldering in an extra capacitor. Below is a link to someone who knows what they are doing and how he fixed his, explains why the m,od is needed and shows you how to do it. Its a well known mod and his worked perfect thereafter (he blew his first time as he didnt know this was a well known fault, there is also a video of that when he reviewed the product first time round. The fault is only a problem if the battery you are using gets low, btw, but that appears to often happen). So this extra capacitor, and using two batteries makes that impossible well nigh on.

I decided to do the mod first and skip the blowing it up part, made sense.

ALSO If you do look at the video, read down the comments somewhere down there is another user of the same modded welder who said use two batteries, one for the weld current and a dif smaller one for the device, I did that as well, he tells you how to connect up the two batteries, it's easy, (I also extended the somewhat short wires to the probes at the same time. Any prob finding it and I'll write it out for you, I have done it, and it makes an awesome welder for peanuts.

The top view photo shows the welder so you can see which one I bought, (E-Bay). The side view shows the extra capacitor in situ side on (Its the one with its top facing you) I used 1000Uf.25V Black cap (usually better quality than the blue ones). If you want any other info, more than happy to take it apart again for you show where it goes, but it's clear on the video.

Modifying it to remove design fault (and fixing it cos he didn't do it first)

Not disposed of anything yet, A W said that if they were just sat there with nothing connected they shouldn't be a problem. I kept them for a reason, I'm going to do some experiments (as and when I find time) then bin them.

On that I have just done same experiments on ten Li ion cells 29e, that had 0v open circuit, been sitting in water, and one had a hole in, guess what, so far even the one with the hole in is fixed and working that was the least likely to fix, photo of it below re wrapped but you can see the solder repair, i used fine copper wire in the solder like fiberglass I suppose.

So far looks like I have three working 36v pouch cell batteries.

Good luck with the welder

K

 

[Lucifer]

It seems to be Frozen or maybe lost its threads I don't know why some of these disappear but he has a lot of good information dark Angel.
Hopefully a moderator can chime in and help as I didn't understand why I couldn't pick up his old threads?
Plus I'm looking at battery spot welders maybe you can start a thread on your spot welder and how you got it to work so well I see some blue to capacitor spot welders for under $90 able to weld 03 pure nickel.
Have you gotten rid of the batteries that are old or unusable ?

Oh there are also a couple of videos on tips how to use it and get the best results, like the angle of the electrodes on the cell, and the amount of pressure to use, one said round off the electrodes a bit which I also did, not sure if it makes any difference, but the pressure and angle do. All on youtube, You will find a lot saying its rubbish and fails quickly after a few welds, thats due to not enough remaining current during the weld process (which is auto, get a couple of bleeps when you maske contact then the weld). The extra cap prevents that happening, as does the two battery setup.