word of advise load test that bms and watch your cell voltage ive had several have one row drain faster than the others if that happens just make sure your pack is balanced and does not drain the same way with out the bms if it dont the bms is faulty. Its mainly noticeable when the pack is about dead one row will be up to .5 volts lower then the others. One other thing solder wick works really well and braided copper is an option as well.
Steven, Awesome, thanks for the advice. I will do a bunch of testing and see what the results are. When I was running my portable power pack with no BMS I found that I needed to balance my cell pack about every 3rd charge. I was hopping that adding the BMS would help resolve that issue. Another problem I had with my small power pack was that I would over discharge my cells and I ended up killing 8 cells. I installed this BMS and it has been working great on my small 32p 4s battery pack. I think I may even do a video on your recommended testing. Thanks again, Frank
Rather then terminating the pack from corner to corner , terminate the feed wire in the center long side so all current only needs to travel from ends to center. In other words the shortest path is the least resistance..
Remember that electric blanket thing you demonstrated in previous videos? well i have one same model as it for some time given the crap weather we had in the uk over the weeks ive been using it however it seemed to go into dead short then open circuit , so i opened it up to find that two the wires had bridged and somehow became exposed , the insulation on the wire is not silicone heat resistant so i just thought id tell you about this in case your family members may encounter the same fault. Oh and i ran it at about 12v@3amp consumption.
Alberto, Funny you should mention that. I have been working on some ideas on charging my Portable Power Pack (goo.gl/jEMMF1) using solar panels like these: amzn.to/2FKZaVO. I might even build my own solar panels that could fit into a case that mounts to the top of my power pack. What do you think?
Frank Brand, adding solar panels to the power packs really seals the deal on the self producing side of solar and using that solar panel briefcase will really do the job.
Frank Brand, I was looking around for a charge controller suitable for lithium batteries and I found one that works with 3s configurations and even 4s configurations. Here’s the link, www.amazon.com/gp/aw/d/B01D2Y5LT0#Ask
is there a particular reason you twist the wire? other than size? I'm thinking about using 8gauge solid copper wire, with 5 amp fuse per cell. I'm building 20 cell packs. then connecting 7 in series. I am also looking for a 7s BMS balance board on the cheap. if that's a thing. a actual good cheap BMS. great video.
Any 7S balance board will do the job well. What you want along with the BMS is a low voltage alarm, and a voltmeter, and a balance port for periodically balancing the cells.
Thanks James. I'm using the twisted wires mainly because I was concerned that with these 12 volt batteries a single strand of 14 gauge wire would not be enough. If the battery packs were 48 volts then a single strand of 14 gauge would work just fine. Here is a link to a inexpensive 20 amp 7s BMS on Amazon.com, I h ope this helps. amzn.to/2Fn7VF9
Twisting the wire also makes the new core more stable. It's easier to bend and solder into place. Plus, it just looks neat ;) But as Frank mentions, the twin twist will allow for a lot higher of amp draw without overheating the wire. A single core strand of the 8awg will not be able to dissipate the heat as effectively as a twin twisted strange of 14awg.
I've been researching all of this type of thing for a while now, and it that time techniques have been evolving. I just subbed, and hoping to learn some new good tips from you. My family and myself will be travelling Australia indefinitely in a 5th Wheeler RV, so the top will be covered in solar panels. So I want to adopt this type of method for my power storage and usage. So are you an electrical engineer?
appreciate the video, Frank. so as I follow along the previous video you were making 40p 4s x3 so now for the sake of flow you've consolidated into 1 pack of 3x 40p 4s? I can't wait to see the wiring as I'm a little confused as what that might look like.
Hey Tim, So the end result will be 3 separate 12 Volt batteries (Technically I will be running them at 15.5 volts at full charge.) Each 12 volt battery is built from 120 cells (18650). The cell are divided into 4 groups with 40 cells per group (40p). The 40 cells are then soldered in parallel (all the positives are soldered together and all the negatives are soldered together). Then the 4 groups of cells will be brought together and soldered in series (positive to negative, positive to negative, positive to negative). That's how you get a 40p 4s battery pack. I cover this in this video: ruclips.net/video/CxzbpFo4nc4/видео.html I hope this helps. Thanks for watching. Frank
To add a little clarification, a 4s40p is not the same as 40p4s. Electrically they are the same, but physical wiring is not. 4s40p = 40 cells connected in parallel, then take 4 sets of these and connect in series 40p4s = 4 single cells connected in series first, then 40 of these connected in parallel. This method is highly difficult to control with a bms as you would need a separate one for each 4s set. So in the video, Frank made a 4s40p. In the title he put it correctly, in the description he flips it (🤔)
These batteries will be going into a tight space so I was trying to conserve space. I actually rethought that and the New busbars are longer. ruclips.net/video/WtyU9oDM-pM/видео.html Several of my cells came from old laptop batteries I bought on eBay. I have not always been so lucky. There was one time I paid $100 for a bunch of laptop batteries... All the cell in the batteries were bad. :-(
I am really struggling getting normal quality batteries. salvaging old laptop batteries from friend's PC shop is not enough. Buying salvage cells on ebay is ok, but shipping 8$ per kg raises costs significantly. :(
I have a question why risk using resistor legs as a fuse when you can purchase 3mm X 10mm axial with lead wire fuses at $10 for 1000 of them on aiexpress I guess I look at it as if you were eating cereal you eat out of a bowl not a flat dish so if you need a fuse why not use an actual fuse just thought I'd ask
Me too I still don't understand why people using resistor legs as fuse it it can hold only 4 amps ... There are fuses capacity with 5amps Is that resistor pack is cheaper ...?
The pack with the transparent cover looks amazing, my only point would be to user a better BMS, those BMS are not great just because if they die would be difficult to see what was wrong, my recommendation would be Battrium BMS. Yes, it is more expensive but you can really trush on it. Look at this (at 2:15): ruclips.net/video/luM9ZaqfrBk/видео.html
I have not been able to find a Battrium BMS that does 4s. All I have been able to find are the LongMons that work great on 1s cell packs. Any more information you might have would be great. Thanks for watching. Frank
2:23 any one else cringe at this moment? At this point i was like dude are you crazy?!?! 10:43 You need to be safer with there batteries! I'm sure you know but the whole bottom case of a battery is negative so the chances of you shorting a cell out is high of not insulated 100%. Risky business
I wish I was as baked as you are in this video
word of advise load test that bms and watch your cell voltage ive had several have one row drain faster than the others if that happens just make sure your pack is balanced and does not drain the same way with out the bms if it dont the bms is faulty. Its mainly noticeable when the pack is about dead one row will be up to .5 volts lower then the others. One other thing solder wick works really well and braided copper is an option as well.
Steven, Awesome, thanks for the advice. I will do a bunch of testing and see what the results are. When I was running my portable power pack with no BMS I found that I needed to balance my cell pack about every 3rd charge. I was hopping that adding the BMS would help resolve that issue. Another problem I had with my small power pack was that I would over discharge my cells and I ended up killing 8 cells. I installed this BMS and it has been working great on my small 32p 4s battery pack. I think I may even do a video on your recommended testing. Thanks again, Frank
Rather then terminating the pack from corner to corner , terminate the feed wire in the center long side so all current only needs to travel from ends to center. In other words the shortest path is the least resistance..
Hey Frank where are you looking for the next video.
Awesome video, very informative!
Remember that electric blanket thing you demonstrated in previous videos? well i have one same model as it for some time given the crap weather we had in the uk over the weeks ive been using it however it seemed to go into dead short then open circuit , so i opened it up to find that two the wires had bridged and somehow became exposed , the insulation on the wire is not silicone heat resistant so i just thought id tell you about this in case your family members may encounter the same fault. Oh and i ran it at about 12v@3amp consumption.
Steve, good to know. I will keep an eye on it. So far it seems to be working fine, but nothing is perfect. Thanks for watching.
Ouch your thumb looks like it felt really good! True diyer
Hi ! Incredible work dude. How would you output a constant 14v out of it with a decent amperage (100a)?
the black and silver looks awesome. I guess that is the clear shrink wrap?
Thanks James, Yes it is a clear cell wrap. I loved how the clear wrap made the cell stand out. :-)
Hey Frank, where did you get these battery holders? Looks so neat!
It would really help if you could figure out a way to charge a 40p4s battery pack with a solar panel and a pwm solar charge controller
Alberto, Funny you should mention that. I have been working on some ideas on charging my Portable Power Pack (goo.gl/jEMMF1) using solar panels like these: amzn.to/2FKZaVO. I might even build my own solar panels that could fit into a case that mounts to the top of my power pack. What do you think?
Frank Brand, adding solar panels to the power packs really seals the deal on the self producing side of solar and using that solar panel briefcase will really do the job.
Frank Brand, I was looking around for a charge controller suitable for lithium batteries and I found one that works with 3s configurations and even 4s configurations. Here’s the link, www.amazon.com/gp/aw/d/B01D2Y5LT0#Ask
I see you use fuse wire. How do you know what kind of wire you use and for what load they are made for?
I mean if you are doing a U shaped bus bar it seems like you could just orientate the bus bars so that the same end would be the ends of the battery
Good point, I think I want to do some testing to see if it makes a difference or not. I was just trying to think logically. 😎
Anyway I can send new pack I built to you in order to get good welds ?
Great job love the diy thumb too...!
is there a particular reason you twist the wire? other than size? I'm thinking about using 8gauge solid copper wire, with 5 amp fuse per cell. I'm building 20 cell packs. then connecting 7 in series. I am also looking for a 7s BMS balance board on the cheap. if that's a thing. a actual good cheap BMS. great video.
Any 7S balance board will do the job well.
What you want along with the BMS is a low voltage alarm, and a voltmeter, and a balance port for periodically balancing the cells.
Thanks James. I'm using the twisted wires mainly because I was concerned that with these 12 volt batteries a single strand of 14 gauge wire would not be enough. If the battery packs were 48 volts then a single strand of 14 gauge would work just fine. Here is a link to a inexpensive 20 amp 7s BMS on Amazon.com, I h ope this helps. amzn.to/2Fn7VF9
Twisting the wire also makes the new core more stable. It's easier to bend and solder into place. Plus, it just looks neat ;)
But as Frank mentions, the twin twist will allow for a lot higher of amp draw without overheating the wire. A single core strand of the 8awg will not be able to dissipate the heat as effectively as a twin twisted strange of 14awg.
Did you buy your battery holder that size from somewhere or are they individual modular pieces that you can put together?
thanks sir
Wow, that pack looks really great with the reskinn, what did you use to reskinn them?
I've been researching all of this type of thing for a while now, and it that time techniques have been evolving. I just subbed, and hoping to learn some new good tips from you.
My family and myself will be travelling Australia indefinitely in a 5th Wheeler RV, so the top will be covered in solar panels. So I want to adopt this type of method for my power storage and usage.
So are you an electrical engineer?
Is that harvested cells or new cells with same internal capacity..?
What BMS did you use?
why not 24V? or is cause you had you inverter at 12v already?
What does bus mean? What does 4s and 40p mean?
it means you have 4 cells in series to get just over 12 volt and 40 in parallel to increase the capacity and max amperage of the pack
appreciate the video, Frank. so as I follow along the previous video you were making 40p 4s x3 so now for the sake of flow you've consolidated into 1 pack of 3x 40p 4s? I can't wait to see the wiring as I'm a little confused as what that might look like.
Hey Tim, So the end result will be 3 separate 12 Volt batteries (Technically I will be running them at 15.5 volts at full charge.) Each 12 volt battery is built from 120 cells (18650). The cell are divided into 4 groups with 40 cells per group (40p). The 40 cells are then soldered in parallel (all the positives are soldered together and all the negatives are soldered together). Then the 4 groups of cells will be brought together and soldered in series (positive to negative, positive to negative, positive to negative). That's how you get a 40p 4s battery pack. I cover this in this video: ruclips.net/video/CxzbpFo4nc4/видео.html I hope this helps. Thanks for watching. Frank
120cells??? Is that modern math? Back when I went to a one room school house, 4 x 40 equaled 160. What am I missing here? ¯\_(ツ)_/¯
To add a little clarification, a 4s40p is not the same as 40p4s. Electrically they are the same, but physical wiring is not.
4s40p = 40 cells connected in parallel, then take 4 sets of these and connect in series
40p4s = 4 single cells connected in series first, then 40 of these connected in parallel. This method is highly difficult to control with a bms as you would need a separate one for each 4s set.
So in the video, Frank made a 4s40p. In the title he put it correctly, in the description he flips it (🤔)
Why not making busbars longer so u can put a connector straight on it :)
BTW where do u get batteries so cheap?
These batteries will be going into a tight space so I was trying to conserve space. I actually rethought that and the New busbars are longer. ruclips.net/video/WtyU9oDM-pM/видео.html
Several of my cells came from old laptop batteries I bought on eBay. I have not always been so lucky. There was one time I paid $100 for a bunch of laptop batteries... All the cell in the batteries were bad. :-(
I am really struggling getting normal quality batteries. salvaging old laptop batteries from friend's PC shop is not enough. Buying salvage cells on ebay is ok, but shipping 8$ per kg raises costs significantly. :(
I have a question why risk using resistor legs as a fuse when you can purchase 3mm X 10mm axial with lead wire fuses at $10 for 1000 of them on aiexpress I guess I look at it as if you were eating cereal you eat out of a bowl not a flat dish so if you need a fuse why not use an actual fuse just thought I'd ask
Me too I still don't understand why people using resistor legs as fuse it it can hold only 4 amps ...
There are fuses capacity with 5amps
Is that resistor pack is cheaper ...?
Can we connect all 40 negatives and 40 positives together
I mean negatives upside and positives down??
Plz reply
yeap but in this case you get only 4.2 v /80 A
Wow Frank, you are awesomeness! How do you do it?
Thank you Ray. I found that by not sleeping I can get more done. :-)
regular household wire ? what gauge is that ?
where do you get the black battery holder clips?
Olá amigo quero montar um pack igual a este .. em 12v pode me ajudar e dizer qual o modelo de bms que posso usar ? Ou comprar no ali express
Give prices of everything in pull down or captions.
Could you link the resistors you used please?
Sure, here is a link to some 1K ohm 1/8 Watt Resistors. amzn.to/2FvXJWI I hope that helps. Frank
Oh yea, it’s already together 62.7v
The pack with the transparent cover looks amazing, my only point would be to user a better BMS, those BMS are not great just because if they die would be difficult to see what was wrong, my recommendation would be Battrium BMS. Yes, it is more expensive but you can really trush on it. Look at this (at 2:15): ruclips.net/video/luM9ZaqfrBk/видео.html
I have not been able to find a Battrium BMS that does 4s. All I have been able to find are the LongMons that work great on 1s cell packs. Any more information you might have would be great. Thanks for watching. Frank
Um just buy a 12V 100ah Lithium Iron LiFePo4 Deep Cycle Rechargeable Battery about $600 ............safer
Now what would be the fun/learning experience you'd get from that?
2:23 any one else cringe at this moment? At this point i was like dude are you crazy?!?! 10:43 You need to be safer with there batteries! I'm sure you know but the whole bottom case of a battery is negative so the chances of you shorting a cell out is high of not insulated 100%. Risky business
Calm down
Jeez that's .1 kwh
Repeat same thing in 13 minutes
Would you trust a man with a bruised thumb ............Haaaaaaaaaaaa
Bms=0000
Really? all is wrongly done, not safe and very dangerous.
Fusing both sides of the battery back is a waste of your time you should just stop doing it