Hey I wrote a comment yesterday about my 52v battery that I could only get a reading of 14.5 volts out of. You replied saying I could do a zoom but I just thought I would write another comment to tell you what I would consider to be very important information before we go on the zoom. So I opened the battery a couple minutes ago to test the voltage, and I put the negative prong on the negative nickel strip and positive on the positive nickel strip, and I got a reading of 58.2 (52v is 58.8 full charge) so that’s the right voltage. Part of the bms wires are exposed so I put the negative prong on the negative bms wire and the positive prong on the positive wire. It read the exact same voltage of 58.2. Before, my worry was that the positive or negative wire wasn’t soldered on good enough, but now I know that they are and both give the correct voltage. This is good, because now I know 100% that it is an issue with the bms and not something else. I am going to book a zoom call as I would love to hop on a zoom call with you to get this figured out. Especially now that I know the problem. I just thought I would write this comment to let you know what I’ve narrowed it down so that way on the zoom we can get it fixed.
@@GaiusGarage What day/time for the zoom works best for you? I have a lot of free time so I just want to make sure to book a time where you have the full time and focus to help me out. Just lmk what works best
Serious pack build Hands down the best video on the topic. Great method for durable bonding and agree with the copper buss and soldering technique you employ. Hard to get the Samsung 30Q 3000mAh Got to choose from what isn't sold out. And as with everything post pandemic they are more than before. Certainly in Aug 2023 you are looking at ~$900 USD for 84V 20A alone. I would buy an 84v 23S 10P pack off the shelf but it is a fools game. No BMS and no idea as to brand of 18650. I have to give serious thought to replacing the lead acid batts in my Damak Eagle
you must not divide the current carried by the number of cells because the nickel connecting them will see the entire load of all 14 cells put together in the group. now the load for each battery cell in the group will be divvied between them, but the nickel connecting them will see the entire load of all the cells in the group
Bro, you should definitely make a huge batch of those cell holders, because those are hands down the best design I've seen in the least bulkiest. and I know a lot of people would love. to get their hands on it to save space on their battery builds.
Know what ?? I will use a 550 watt soldering iron to solder the copper strips !! Fast job ! My original idea is to melt things to hell with this thing . Also , that you have said for 220 amps , that can easily output about 800amps if needed , or that is what I would let it do . Well if you think where the heck did I get the idea of doing destruction with this beast , have a look at the channel named : COLIN FURZE !!! He is an absolute beast !! This channel too is amazing ! Nice videos ! Keep it up ! Hope you get a sponsored soon !
With the prices of batteries, debating dipping my toes into trying to build a pack. I need a larger AH battery, the options are just too expensive though. Thank you for showing me the basics.
thanks! yeah Im never opening this thing back up to service it - if one of those come loose or dislodge this whole thing will be significantly stifled or completely defunct. just thinking in terms of all the vibration over time and climate effects plus electrolytic corrosion - I really dont think I did a good enough job. but still nice a balanced a year later!
@@GaiusGarage Ya welcome! Honestly, the only other thing ya could have done is that after soldering, but before folding it up, was conformal coat the internals!
Hi, I am a highschool student and for a fun project I decided to build an electric pit bike, as well as building a custom battery to fit the spacing required. I custom built a 52v 28.8ah (14s12p) battery with samsung cells and before I put the bms (50a 14s Daly BMS) on, I tested the pack with a voltmeter and it read around 58.6 volts, which was perfect. However, when I soldered the bms wires on, and put on the connector, it read 14.5 volts. That was around a month ago, and now when I test it the voltmeter reads around 9.5 volts. I checked all of the bms wires and they were fine, so I don’t understand how I am getting that voltage. I saw online that sometimes a BMS can be “asleep” and that you can wake it up by charging, so I tried that and it didn’t even charge. I am now feeling very frustrated and defeated, because everything went so well until the BMS part. Everything in terms of the nickel strips and batteries is good, but it is just something with the BMS. I wasn’t able to get a very good solder on the main positive wire, so that could be the issue. This is all for an electric pit bike project that I’m doing, and I just feel very defeated now, which is why I’m seeking external help. Sorry for the very long email, but this is just the problem that I am facing. Do you know a possible fix or any way I can contact you for you to provide further help. Thanks in advance.
I've also experienced this and haven't yet found a solution. I ended up using a different BMS, making sure to use flux and minimal heat when soldering the leads. I also had the balance wires unplugged when soldering the first BMS so I'm not sure if plugging them in and soldering the cells in order made a difference. My best guess is that a protection circuit has been triggered or one of the cells isn't being registered making the BMS shut down due to low voltage. I hope you find a solution.
I can help you debug over zoom - please feel free to book a 30 min session on my Calendy. you would need at least a multi-meter to do some testing. If I cant help I will refund the cost calendly.com/gaiusgarage
@@NaTe4825 Oh ok thanks. I had the balance wires unplugged from the main connector when I did it so that’s possible to make a difference. I’m going to see if there are any wires without a strong connection or something. Thanks for the help and the wishes, I appreciate it
@@GaiusGarage Ok that sounds good. And for you refunding me if you don’t help, does that mean if you can’t help me get the battery working or just if you can’t help me at all. I have a multimeter. I do have a question about the multimeter if you know though. When I first read the voltage and it read 14.5, I decided to switch around to the different multimeter settings. On of them, which reads uA (macro amps) I got a reading of 54.6. Do you know how I could have gotten an amp rating out of it?
Thank you! The charger I use is custom made - just a 1500W power supply connected to a boost converter. This is the cheapest option to charge at >10A - chargers for sale at >10A tend to get in the hundreds of dollars. Here's an example of what I'm describing but at 100V (so current is lower). th-cam.com/video/tSj76sVALwg/w-d-xo.html
I got another question: I already finished my project and everything seems to work fine. I connected the battery to a 6kw QS motor. When the battery reaches 60% discharge while using it... suddenly the voltage goes to cero and the battery discharges empty.... so sad...@@GaiusGarage
@@romanominghi2990 not sure. maybe BMS is misconfigured - impossible to determine given the info provided. please feel free to book a consult and I can try and dig into the details calendly.com/gaiusgarage/30-min-consult
I want to build a 24 V -500 Watt battery, for a stroller for a child with locomotor handicap. I don't know how to assemble them, nor how many batteries I need, if you have a sketch, a technical drawing please. thank you very much
I can definitely help design this battery pack and provide some technical drawing. please feel free to book a session on my calendy calendly.com/gaiusgarage/30-min-consult
great video, clean build! i'd like to add to the importance of using insulator rings, my 12.6v 60aH build after 3 years had about 8 cells "pop" because the nickel somehow punctured into the factory protective film at the top of the cell (positive side), causing the positive to meet the battery shell (ground). First time i've ever smelled li-on fumes and surprisingly smelled like Lychee candy lolll. Ever since then, i've used insulator rings on all my builds, and still paranoid!
Great job! I have a question, when did you set up the battery pack to show as empty? When it reach nominal voltage or less like when it reaches 3.2v per cell ? Because when having a high discharge battery pack I'm confused where to set the SOC as empty Thanks
its a bit of an arbitrary definition - 2.5V is the physical low limit for li-ion batteries below which will cause physical damage to the cells. If you wanted 0% to represent the actual physical limit, 2.5V would be the value. that said, the energy curve for li-ion cells is not linear so the amount of energy between 3.0V and 2.5V is significantly less than between 3.0V and 3.5V, for example. In fact, most of the energy per cell is roughly between 4.2V and 3.6V. so if you're looking for a more practical value, perhaps one to set as a low-voltage cut off for the BMS or controller, I would go with 3.0V per cell. If you want to be a bit more conservative and focus more on cell health and longevity, 3.2V/cell could be a good option as well. I would also recommend not going below ~3.4V / cell for everyday use, and not charging to 4.2V/cell (studies show that charging to 4.15V increases battery life by 20% while the energy difference between 4.15 and 4.2 is only like 3-5% so you get a lot more battery life for very little loss in usability). here is a link to a curve that I use for all SOC setting: imgur.com/a/z8C1fzE
yeah I was originally going to build 16p but there was no way to arrange the cells to fit in the frame. 20p would be huge! links to pics of the bike in description!
@@GaiusGarage I am going to use this same layup (2x7)x4x5 however I will check wether a (2x10)x4x5 configuration or (3x7)x4x5 would fit the frame best.
Hi, Did wraping the battery in hear restant foam cause any heating or overheating or slow cooling issues? I want to wrap the battery i am building in foam as well for decrease vibration but am hesitant about overheating issues. Great built.
No, I never had any issues with overheating. heat is not really an issue unless you're really pushing a battery pack to it's limits. in this case, I would only run it at max discharge for short periods of time (when accelerating hard) but most of the time the demand was much more moderate. so overheating was not an issue even when wrapped and placed somewhere with little airflow
please book a project consult with me on Calendly. It's $25 but cost will be applied to your build if you decide to move forward. If I can't help, I will refund you the full amount. calendly.com/gaiusgarage/15-minute-consult
Really nice job and great battery pack, but I belive that you shouldn't trim bms balance wires, it introduces resistance difference in wires and could interfere with the bms readings
thank you! interesting thought on the balance wires - to my understanding the BMS is measuring the voltage potentials only from the balance wires, in which case the current (dependent upon resistance) wouldn't matter. but if the BMS performs some other functions that depends on measuring current in the balance wires with some high degree of precision, then their length might play a role
Absolutely superb in depth video.So well explained and filmed put. Like many here, I’d love to see this on the bike that its been made for and demonstrated 😊 👍
ditto to the above comment by jonnyswlk4674, i canna say anything more, this is the best instructional video i ever saw, alas i don't understand much of it lol.
@@GaiusGarage Hi hello sir, may I allow to ask a question and please help reply with your expertise on ebike battery. Yesterday when I was paddle my ebike at home with the parking stand mount on the floor, for testing the ebike speed, then suddenly my mother was talking to me, instead of I need to press the hand brake to stop the spining ebike, I turned off the ignition key, THEN I heard a "pop" sound (the motorhub was still in high speed spinning) I don't know the "pop" sound was came from the battery or came from the controller. Sir, may I ask in most of the cases, let say, if a person paddle the ebike halfway through, when the battery still on going supplying the energy into the controller, and the controller still on going supplying the power into the motorhub, and the motorhub still drawing power spinning at fast speed, then he turn off the ignition key OUT OF SUDDEN to cut off the ON GOING power supply intake from the battery, in this case what will happen to my battery? Sir, please help me, then I unpluged the ebike power plug from the battery, then I turn on the key ignition to purposely release the electric in the controller, then I plug the ebike power plug into the battery and heard a as usual spark sound. My concern now is, how do I know I already wound, injury, or damage my battery or not sir. Hope you understand my question, trillion thanks if you would please reply sir.
@@GaiusGarage it's ok to charge from the main output connection on these batteries? my EUC battery has two pairs of smaller black and red wires coming out that don't indicate any voltage
The packs that the suppliers and sellers sell are junk. The suppliers use cheapest quality batteries to sell to the sellers for profit rather than pure performance and longevity. Not only that but they also use cheap fake nickel strips to connect these cells together and many of them don't even apply 2 or 3 layers just a single so you are asking for trouble for resistance and heat build-up which means the power from the battery cells get wasted as it heat turns it to waste energy that cannot be used. The only real solution is to build a battery pack yourself. There are better and easier and simpler methods. Build it with ultra-performance cells like the Samsung 21700 40T which the suppliers would never use due to high cost. It's a lot cheaper to get cheaper outsourced batteries from China. Hypothetically, even if they use the 40T cells they are gonna use cheap connections to connect them together which means the power will get wasted. You really gotta build the pack yourself.
Are the multiple wires from the bms on both positive and negative just to spread the amps over 4 wires ? Is it best to solder them like you did in different places along the mains pos and neg area of the 72v battery or does it not matter ?
@@cajab7407 yeah it's just to distribute the amps over several smaller wires vs. using a very think wire - generally you would do this to make it more flexible and easier to solder. if you have the option it's better to spread out where they're soldered
You are correct, when you put cells in parallel they attempt to charge each other. However, that is not a whole story, because when the batteries begin to discharge, the more charged cells will attempt to charge the less charged cells. This reduces the total output of the battery as you draw power from it. The only method I have found to prevent this, is to put a schottky diode on the output of each cell, then tying the diode cathodes together. Or you could at the end of the series, which will reduce the amount of diodes necessary. It really depends on your battery configuration.
@@Matt-og5kd That's a good question, I don't think it affects TOO much, since this is a configuration found in car batteries. It might slightly increase charging time perhaps?
Brilliant stuff, I'd have watched this if it was normal speed the whole build. If possible, could you release an unedited build showing every moment, like you did here but without speeding up or doing cuts. Either way this was the best battery video for powerful ebikes I've found from months of looking
thank you! I actually don't have the raw footage anymore but even if I did it would be hours of footage. is there anything you wanted to see more closely in particular?
@@GaiusGarage oh belive me I know it would be hours haha and it was more interest toward the techniques used throughout the process, this video covers everything in wonderful detail, I was just thinking if you're doing the battery build anyways filming the workspace even without talking much would show the nuance detail. Again this video is easily great enough for using as a building manual. I just really enjoyed this build and if a future one is ridiculously long I would just watch it in sittings a few times over before going about building my own powerful battery. Just something to throw out there if you were looking for any ideas. All the best mate 👍
that wire is the on switch for the BMS to "wake it up". its kinda pointless because you can use it to turn the BMS off and the BMS turns on automatically when you draw power from the battery. Im charging using a 1500W AC-DC power supply and a step-up converter as a voltage regulator
I have seen videos of rion and they use a custom made machine to spot weld copper directly into battery cells, like this wouldn't you be unable to ever swap cells if needed, rendering the entire battery useless if lets say there is a critical imbalance between cells or some cells get damaged... couldn't you use just the nickel strips?
yes, any amount of voltage is dangerous and becomes more dangerous as the voltage increases. always use gloves and take precaution when working with high voltage
thanks so much! this music is from a great playlist I found on youtube a few years ago - lots of other awesome tracks check it out th-cam.com/video/uL0mvPZuklM/w-d-xo.html
If you attach a BMS to your battery pack does that mean that you can charge them from a rectified transformer where you can adjust the dc output voltage to your battery pack ? Like mains ->variac -> transformer -> rectifier -> capacitor -> battery pack. That would be cheap at least for me. Of course with a current limiting resistor between the battery pack and your supply.
The foam between layers of the pack is a bad idea. You either want the cells to be in direct contact with each other so that heat from cells at the center of the pack can be conducted outward, or you want to have aiflow through the pack. Having neither, you increase sag as the inner cells heat up.
Hey man, VERY well done. That battery is overbuilt in the best possible way! Question for you... I picked up this crazy prototype battery a while back (I work with batteries professionally), and am really curious if its feasible to use it for an e-bike. Coincidentally, its cells are also Samsung 30Q, and this thing was clearly designed to harness the full 15A from each cell (each cell is thermally mated to a liquid cooled aluminum block!!). Here's the thing: the pack is configured as a 24S 12P (86.4V 36Ah) and can't be rearranged. Now, I am familiar with plenty of BMSs and chargers for 24S setups, but I am still mostly an outsider to the e-bike world and am struggling to find compatible parts that are practical and affordable. So I was wondering if you would happen to know of anything like that. I have a 700c road bike I'd like to convert, but I'm open to other ideas too. Also I'm happy to 3d model and print custom parts if need be. Thanks in advance.
The difference between 20s and 24s is pretty small - a lot of overlap in voltage (20s is 84V fully charged, 24s is 86V nominal) so for the most part, you should be able to easily find components that work for both. Basically, the only constraint will be the motor controller - one design for 20s will probably get damaged if connected to 24s fully charged (100.8V). But its easy to find motor controller that will work for 24s -- anything with a max current above 100V will work. I wouldn't worry about the motors - any motor that will work for 20s will also be fine on 24s.
Everything seems to be well thought of. However, the 8 AWG wire going into the EC8 connector threw me off. Isn't that gauge rated for maximum 45A? what am I missing?
that rating pertains mostly to residential wiring. you can run pretty much any current through any wire, with the factors being voltage drop, length of wire, time the current is applied. for short runs (pretty much anything on an ebike or battery pack) the voltage drop is miniscule even at 200A. if you look up what gauge wire is "rated" for 200A, I would have to use zero gauge, which would be ridiculous
Hi. Thanks for this great tutorial video. I was wondering if its easier to build what you did here using 9v batteries. What are the obstacles that you will come across with building a pack with 9v batteries?
@@Jay-tr3px for one the typical one you buy at the store are single-use so it would be pretty impractical to build one and throw it in the trash after one use. there are rechargeable versions of these batteries (actually called "PP3") but the capacity on these is pretty low (~0.5Ah) so you would need 84 in parallel & 8 in series (672 total) to get a comperable battery pack. and then they aren't going to have near the discharge capability - pretty much a bad idea all around
@@GaiusGarage Oh ic. Thank you for the update. I would really love to see you do a video on making existing battery packs that comes with ebikes and putting them in series/parallel together and making a higher voltage and range battery pack to use on the same bike or for your own projects. Thanks again
I’m curious as to how this is a 220A max cont pack when 14 cells in parallel is 210A which each cell having a max cont of 15A , 15A x 14 in parallel is 210A and how does that then have 300A peak discharge can someone elaborate?
@@ioandragulescu6063 depend on the rate of charge. Charging at 1C (40A) would take 1hr. Can be fast-charged at up to 3C (although not the best for cell longevity) and that would take 20 min
depends what you mean by Enduro frame but if you're talking about the one common frame often referred to as "Enduro", the answer is no. I actually had that frame and sold for the "stealth bomber" frame it to fit this larger battery, and even then it barely fit
How can this battery be utilized as to what i/o needs to be connected to get a 3 prong 110v outlet to power on a microwave, phone, smartphones, tablets, and a solar panel for charging this battery pack...etc... mainly I'm thinkin off grid R.V.
you wouldn't use a battery pack like this for off-grid because the voltage is too high and it was designed for high current draw, which you typically wouldn't need for off-grid. you'll have trouble finding components and will have alot of losses in efficiency. generally off-grid systems use 12V, 24V, or 48V battery systems. youll need an inverter to get AC power from a DC battery like this
Excellent work. Very nice build. I cant find the 220 continuos 300A max discharge BMS. The ones available are 240A continuous but 550A max. Im usisng 14P sony VTC6 cells so I have max 420A discharge. Should I go for a lower continuos discharge? Let's say 170 continuous 425A.. Thank you.
I would love to build a battery pack to cover the whole height and length of my ruff cycles smyinz but for now I got a triangle bag for a 52v 21a.h 1500w battery to a 72v 3000w hub motor . But like I said would love to build one that fit the whole frame with as many a.h's as possible
@@kaliraah no not yet I'm waiting on a refund from junstar first then I might get one . But never buy a kit from junstar I had a bbso2 for 6months and battery pack that just went one after the other
I'm sure you heard about the sur ron X ! Did you think this battery can fit in the battery caps of the sur ron and it's possible to work with sur ron motor and bac 4000 Controlor ?
LiFePo4 batteries can't do well in high discharge, not a candidate for high performance needs. They are also 3.2V nominal voltage rated not the 3.6/3.7V nominal so your battery will quit sooner unless you increase the number of series connection in the battery pack.
With 21700's available for Ebike battery packs does it make better sense to do a 20S 8P now? Say at 5100mAh & 3.7V/21700 Cell? Or is it that batteries & BMS using 18650's are still way cheaper these days? Is there any weight savings moving up to 21700's for Ebikes with less parallel rows of cells needed in a pack?
fast-charge is more a function of the charger and power supply than the battery. you should not charge any Li-ion battery pack above 3C or so (and that is probably the waay upper limit) its more risky and will ultimately lessen battery life but you can do it if you want to charge as fast as possible. For this battery pack that would be 3 x 42Ah = 126A (like I said, it's a very aggressive charging rate). So at 84V, 126A means you would need to supply 10kW to achieve this level of "fast-charge" and it would fully charge in 10-15min. So if you have a charger connected to a power supply that can provide 10kW, then you can "fast-charge". I'm just charging at home using a standard wall outlet which is limited to 1500W so my upper limit on charging current is about 17A or 0.4C, which is quite low but good for longevity
How many amps would be this config......??Quick question, I just got a 72v battery pack 20s and believe is 6p, have 120 cells in it (liitokala 5000) but not sure how much amps really is as it doesn't have any labels.
Best part of this project is the cool OG red shop rag on the workbench. Well done, sir...
only 3 minutes in , it's obvious how mucht thought and precausion has gone into the assembly. very nice watch, thanks .
thanks so much!
@@GaiusGarage I was interested in a battery but calendly wants your first born child just to sign up. SHEEESH.🙄
Hey I wrote a comment yesterday about my 52v battery that I could only get a reading of 14.5 volts out of. You replied saying I could do a zoom but I just thought I would write another comment to tell you what I would consider to be very important information before we go on the zoom. So I opened the battery a couple minutes ago to test the voltage, and I put the negative prong on the negative nickel strip and positive on the positive nickel strip, and I got a reading of 58.2 (52v is 58.8 full charge) so that’s the right voltage. Part of the bms wires are exposed so I put the negative prong on the negative bms wire and the positive prong on the positive wire. It read the exact same voltage of 58.2. Before, my worry was that the positive or negative wire wasn’t soldered on good enough, but now I know that they are and both give the correct voltage. This is good, because now I know 100% that it is an issue with the bms and not something else. I am going to book a zoom call as I would love to hop on a zoom call with you to get this figured out. Especially now that I know the problem. I just thought I would write this comment to let you know what I’ve narrowed it down so that way on the zoom we can get it fixed.
Oh nice! yeah sounds like your pack is in good shape, which is the important part!
@@GaiusGarage What day/time for the zoom works best for you? I have a lot of free time so I just want to make sure to book a time where you have the full time and focus to help me out. Just lmk what works best
@@schmeglyomigy6174you can choose a date/time on my Calendly calendly.com/gaiusgarage
Serious pack build Hands down the best video on the topic. Great method for durable bonding and agree with the copper buss and soldering technique you employ. Hard to get the Samsung 30Q 3000mAh Got to choose from what isn't sold out. And as with everything post pandemic they are more than before. Certainly in Aug 2023 you are looking at ~$900 USD for 84V 20A alone.
I would buy an 84v 23S 10P pack off the shelf but it is a fools game. No BMS and no idea as to brand of 18650. I have to give serious thought to replacing the lead acid batts in my Damak Eagle
I'm buying a year old Daymak EM2 today.I want to convert to lithium from lead acid.Videos like this are helpful.Thanx🇨🇦
you must not divide the current carried by the number of cells because the nickel connecting them will see the entire load of all 14 cells put together in the group. now the load for each battery cell in the group will be divvied between them, but the nickel connecting them will see the entire load of all the cells in the group
Bro, you should definitely make a huge batch of those cell holders, because those are hands down the best design I've seen in the least bulkiest. and I know a lot of people would love. to get their hands on it to save space on their battery builds.
Know what ?? I will use a 550 watt soldering iron to solder the copper strips !! Fast job ! My original idea is to melt things to hell with this thing . Also , that you have said for 220 amps , that can easily output about 800amps if needed , or that is what I would let it do . Well if you think where the heck did I get the idea of doing destruction with this beast , have a look at the channel named : COLIN FURZE !!! He is an absolute beast !! This channel too is amazing ! Nice videos ! Keep it up ! Hope you get a sponsored soon !
It's always interesting to see how we bother with wire size but solder can take it all. Same solder can take 10A or 1000A. Beautiful material :)
With the prices of batteries, debating dipping my toes into trying to build a pack. I need a larger AH battery, the options are just too expensive though. Thank you for showing me the basics.
I love how you're not effing around with any of the connections through soldering and spot welding!
thanks! yeah Im never opening this thing back up to service it - if one of those come loose or dislodge this whole thing will be significantly stifled or completely defunct. just thinking in terms of all the vibration over time and climate effects plus electrolytic corrosion - I really dont think I did a good enough job. but still nice a balanced a year later!
@@GaiusGarage Ya welcome!
Honestly, the only other thing ya could have done is that after soldering, but before folding it up, was conformal coat the internals!
That thing is a beautiful monster. I'm sure it could power my whole house for a week.
Not even close, it would power the average American house for about 10hrs
I have built a few packs in my time. This is a nice build.
Thank you!
Hi, I am a highschool student and for a fun project I decided to build an electric pit bike, as well as building a custom battery to fit the spacing required. I custom built a 52v 28.8ah (14s12p) battery with samsung cells and before I put the bms (50a 14s Daly BMS) on, I tested the pack with a voltmeter and it read around 58.6 volts, which was perfect. However, when I soldered the bms wires on, and put on the connector, it read 14.5 volts. That was around a month ago, and now when I test it the voltmeter reads around 9.5 volts. I checked all of the bms wires and they were fine, so I don’t understand how I am getting that voltage. I saw online that sometimes a BMS can be “asleep” and that you can wake it up by charging, so I tried that and it didn’t even charge. I am now feeling very frustrated and defeated, because everything went so well until the BMS part. Everything in terms of the nickel strips and batteries is good, but it is just something with the BMS. I wasn’t able to get a very good solder on the main positive wire, so that could be the issue. This is all for an electric pit bike project that I’m doing, and I just feel very defeated now, which is why I’m seeking external help. Sorry for the very long email, but this is just the problem that I am facing. Do you know a possible fix or any way I can contact you for you to provide further help. Thanks in advance.
I've also experienced this and haven't yet found a solution. I ended up using a different BMS, making sure to use flux and minimal heat when soldering the leads. I also had the balance wires unplugged when soldering the first BMS so I'm not sure if plugging them in and soldering the cells in order made a difference. My best guess is that a protection circuit has been triggered or one of the cells isn't being registered making the BMS shut down due to low voltage. I hope you find a solution.
I can help you debug over zoom - please feel free to book a 30 min session on my Calendy. you would need at least a multi-meter to do some testing. If I cant help I will refund the cost
calendly.com/gaiusgarage
@@NaTe4825 Oh ok thanks. I had the balance wires unplugged from the main connector when I did it so that’s possible to make a difference. I’m going to see if there are any wires without a strong connection or something. Thanks for the help and the wishes, I appreciate it
@@GaiusGarage Ok that sounds good. And for you refunding me if you don’t help, does that mean if you can’t help me get the battery working or just if you can’t help me at all. I have a multimeter. I do have a question about the multimeter if you know though. When I first read the voltage and it read 14.5, I decided to switch around to the different multimeter settings. On of them, which reads uA (macro amps) I got a reading of 54.6. Do you know how I could have gotten an amp rating out of it?
You know its a big ass battery when you need a gas burner to solder, love it!
Hi! Best video for a 72 V battery. Can you suggest me a good charger for it?
Thank you! The charger I use is custom made - just a 1500W power supply connected to a boost converter. This is the cheapest option to charge at >10A - chargers for sale at >10A tend to get in the hundreds of dollars. Here's an example of what I'm describing but at 100V (so current is lower). th-cam.com/video/tSj76sVALwg/w-d-xo.html
I got another question: I already finished my project and everything seems to work fine. I connected the battery to a 6kw QS motor. When the battery reaches 60% discharge while using it... suddenly the voltage goes to cero and the battery discharges empty.... so sad...@@GaiusGarage
@@romanominghi2990 not sure. maybe BMS is misconfigured - impossible to determine given the info provided. please feel free to book a consult and I can try and dig into the details
calendly.com/gaiusgarage/30-min-consult
So dope. We need more videos from you about your bike, builds, specs, etc....
thanks! going to post alot more of those soon, including new bike build with 100V Lipo pack
AmaZing detail. Answered a lot of my questions about large packs.
Thumbs up. Do you remember how much the completed battery pack weighs? It looks like just the cells are close to 13.5 kg.
yeah its something like that. I dont remember exactly
Will the copper begin to rust within the battery later on? That's my only concern since nickel is rust resistant but copper isn't.
Wow! This was an extremely helpful video! Great find! Thanks for making the vid!
I want to build a 24 V -500 Watt battery, for a stroller for a child with locomotor handicap. I don't know how to assemble them, nor how many batteries I need, if you have a sketch, a technical drawing please. thank you very much
I can definitely help design this battery pack and provide some technical drawing. please feel free to book a session on my calendy
calendly.com/gaiusgarage/30-min-consult
great video, clean build! i'd like to add to the importance of using insulator rings, my 12.6v 60aH build after 3 years had about 8 cells "pop" because the nickel somehow punctured into the factory protective film at the top of the cell (positive side), causing the positive to meet the battery shell (ground). First time i've ever smelled li-on fumes and surprisingly smelled like Lychee candy lolll. Ever since then, i've used insulator rings on all my builds, and still paranoid!
I added those here 1:09
@@GaiusGarage yeah, was saying im adding to the importance of it, loved that you put it in the video.
Nice job building that pack. Now show us what type of bike that beast is being mounted onto!
Thanks! link to ebike using this pack is in the description
Great job! I have a question, when did you set up the battery pack to show as empty? When it reach nominal voltage or less like when it reaches 3.2v per cell ? Because when having a high discharge battery pack I'm confused where to set the SOC as empty
Thanks
its a bit of an arbitrary definition - 2.5V is the physical low limit for li-ion batteries below which will cause physical damage to the cells. If you wanted 0% to represent the actual physical limit, 2.5V would be the value. that said, the energy curve for li-ion cells is not linear so the amount of energy between 3.0V and 2.5V is significantly less than between 3.0V and 3.5V, for example. In fact, most of the energy per cell is roughly between 4.2V and 3.6V. so if you're looking for a more practical value, perhaps one to set as a low-voltage cut off for the BMS or controller, I would go with 3.0V per cell. If you want to be a bit more conservative and focus more on cell health and longevity, 3.2V/cell could be a good option as well. I would also recommend not going below ~3.4V / cell for everyday use, and not charging to 4.2V/cell (studies show that charging to 4.15V increases battery life by 20% while the energy difference between 4.15 and 4.2 is only like 3-5% so you get a lot more battery life for very little loss in usability). here is a link to a curve that I use for all SOC setting: imgur.com/a/z8C1fzE
@GaiusGarage many thanks for your professional explanation
Cheers !
Goodness, I will be building a 20s20p and never relized how enormous this would be, i love this design. Would love to see what its for
yeah I was originally going to build 16p but there was no way to arrange the cells to fit in the frame. 20p would be huge! links to pics of the bike in description!
@@GaiusGarage i have not made any purchases in electronics yet however i am thinking of building a 4kW nominal motard
@@GaiusGarage I am going to use this same layup (2x7)x4x5 however I will check wether a (2x10)x4x5 configuration or (3x7)x4x5 would fit the frame best.
21k peak power would probably ignite my Vsett motors in flames like Ghost Rider. 😋
Lite Em UP!
Hi,
Did wraping the battery in hear restant foam cause any heating or overheating or slow cooling issues? I want to wrap the battery i am building in foam as well for decrease vibration but am hesitant about overheating issues.
Great built.
No, I never had any issues with overheating. heat is not really an issue unless you're really pushing a battery pack to it's limits. in this case, I would only run it at max discharge for short periods of time (when accelerating hard) but most of the time the demand was much more moderate. so overheating was not an issue even when wrapped and placed somewhere with little airflow
Hello friend when you build you own fitting the charger to right on so it set on fire 🔥
Please if someone paid you would you building them for you should doing a services available or you own website I e you interested please contact me
S business partnership 50 for you me 40
I need one of these for my ReddyRD1 scooter that has a 60v 38ah battery
*Will Smith Voice
YAAHHH. THAT'S HOTT. That's hott.
What is the best way to learn how to make batteries professionally? thanks
probably by learning to make them as a hobby
How can i get in touch with ?? I need a 72v pack build sir plsee??? Im in Florida!!!
please book a project consult with me on Calendly. It's $25 but cost will be applied to your build if you decide to move forward. If I can't help, I will refund you the full amount.
calendly.com/gaiusgarage/15-minute-consult
How did you hook the main negative and positive discharge wires to the pack
Really nice job and great battery pack, but I belive that you shouldn't trim bms balance wires, it introduces resistance difference in wires and could interfere with the bms readings
thank you! interesting thought on the balance wires - to my understanding the BMS is measuring the voltage potentials only from the balance wires, in which case the current (dependent upon resistance) wouldn't matter. but if the BMS performs some other functions that depends on measuring current in the balance wires with some high degree of precision, then their length might play a role
👍🏻nice build man i miss these kid of video’s. Much appreciated👊🏻
Thanks so much!
I built a vruzend kit battery 54volt.Samsung 25r cells.but got battery sag after a while so bought a green cell battery
Great video. Can i ask what the reason is to fold over each pack of 14 cells?
Thanks! just to achieve that particular form factor
That was a great video I like the way you put the pack together
thank you!
Absolutely superb in depth video.So well explained and filmed put. Like many here, I’d love to see this on the bike that its been made for and demonstrated 😊 👍
thanks so much! pic of the bike using this battery pack is in the comments - going to make a ride video soon!
@@GaiusGarage Looks great 👍 There’ll be a few people (including myself) glad to see that video.|I bet that machine really shifts 👍
ditto to the above comment by jonnyswlk4674, i canna say anything more, this is the best instructional video i ever saw, alas i don't understand much of it lol.
@@GaiusGarage Hi hello sir, may I allow to ask a question and please help reply with your expertise on ebike battery. Yesterday when I was paddle my ebike at home with the parking stand mount on the floor, for testing the ebike speed, then suddenly my mother was talking to me, instead of I need to press the hand brake to stop the spining ebike, I turned off the ignition key, THEN I heard a "pop" sound (the motorhub was still in high speed spinning) I don't know the "pop" sound was came from the battery or came from the controller. Sir, may I ask in most of the cases, let say, if a person paddle the ebike halfway through, when the battery still on going supplying the energy into the controller, and the controller still on going supplying the power into the motorhub, and the motorhub still drawing power spinning at fast speed, then he turn off the ignition key OUT OF SUDDEN to cut off the ON GOING power supply intake from the battery, in this case what will happen to my battery? Sir, please help me,
then I unpluged the ebike power plug from the battery, then I turn on the key ignition to purposely release the electric in the controller, then I plug the ebike power plug into the battery and heard a as usual spark sound.
My concern now is, how do I know I already wound, injury, or damage my battery or not sir. Hope you understand my question, trillion thanks if you would please reply sir.
@@GaiusGarage it's ok to charge from the main output connection on these batteries? my EUC battery has two pairs of smaller black and red wires coming out that don't indicate any voltage
Wish I had time to build these but i have to stick to buying the packs. I only use batteries that use super quality 18650s or 21700s
The packs that the suppliers and sellers sell are junk. The suppliers use cheapest quality batteries to sell to the sellers for profit rather than pure performance and longevity. Not only that but they also use cheap fake nickel strips to connect these cells together and many of them don't even apply 2 or 3 layers just a single so you are asking for trouble for resistance and heat build-up which means the power from the battery cells get wasted as it heat turns it to waste energy that cannot be used. The only real solution is to build a battery pack yourself. There are better and easier and simpler methods. Build it with ultra-performance cells like the Samsung 21700 40T which the suppliers would never use due to high cost. It's a lot cheaper to get cheaper outsourced batteries from China. Hypothetically, even if they use the 40T cells they are gonna use cheap connections to connect them together which means the power will get wasted. You really gotta build the pack yourself.
How would one go about and charge this pack?
Surely that ec3 connector is not for your output to your drive?
Its an EC8 connector - they're rated for 190A -- the controller I'm using with this battery runs 200A peak
what batteries are beter for scooter 18650 or pouch cell of ncm 72v55ah
Now for the hard part, mounting the 72v 42Ah battery.
Luke tamblyn how do you tape your battery to your frame one so it doesnt move and two how do you make it look so good
Are the multiple wires from the bms on both positive and negative just to spread the amps over 4 wires ? Is it best to solder them like you did in different places along the mains pos and neg area of the 72v battery or does it not matter ?
@@cajab7407 yeah it's just to distribute the amps over several smaller wires vs. using a very think wire - generally you would do this to make it more flexible and easier to solder. if you have the option it's better to spread out where they're soldered
I think this would be perfect to extend the range of my Evo3 a little 👍
What are the dimensions about battery please ?
You are correct, when you put cells in parallel they attempt to charge each other. However, that is not a whole story, because when the batteries begin to discharge, the more charged cells will attempt to charge the less charged cells. This reduces the total output of the battery as you draw power from it. The only method I have found to prevent this, is to put a schottky diode on the output of each cell, then tying the diode cathodes together. Or you could at the end of the series, which will reduce the amount of diodes necessary. It really depends on your battery configuration.
how would this affect the battery during charging
@@Matt-og5kd That's a good question, I don't think it affects TOO much, since this is a configuration found in car batteries. It might slightly increase charging time perhaps?
@@DFX2KX The diode will prevent the cell from charging, as the current can only flow one way, so you made a disposable pack - Nice
missing link for heat resistant foam
how much woud it cost to build this battery? if i woud order frome you?
Looks good, but you could have used more cells at the same volume with a different design. How do you support it against mechanical impact?
Insane battery!! Looking forward to a video about the ebike!
Brilliant stuff, I'd have watched this if it was normal speed the whole build. If possible, could you release an unedited build showing every moment, like you did here but without speeding up or doing cuts. Either way this was the best battery video for powerful ebikes I've found from months of looking
thank you! I actually don't have the raw footage anymore but even if I did it would be hours of footage. is there anything you wanted to see more closely in particular?
@@GaiusGarage oh belive me I know it would be hours haha and it was more interest toward the techniques used throughout the process, this video covers everything in wonderful detail, I was just thinking if you're doing the battery build anyways filming the workspace even without talking much would show the nuance detail. Again this video is easily great enough for using as a building manual. I just really enjoyed this build and if a future one is ridiculously long I would just watch it in sittings a few times over before going about building my own powerful battery. Just something to throw out there if you were looking for any ideas. All the best mate 👍
@@GaiusGarage hello big brother im live in turkey can you gift me another litle battery please?
@@memcan5602 😂
@@Anees- our money is worthless
Brilliant build.
Do you make batteries for people, what’s cost
What is the thin third wire used for? How do you charge the battery?
that wire is the on switch for the BMS to "wake it up". its kinda pointless because you can use it to turn the BMS off and the BMS turns on automatically when you draw power from the battery. Im charging using a 1500W AC-DC power supply and a step-up converter as a voltage regulator
I have seen videos of rion and they use a custom made machine to spot weld copper directly into battery cells, like this wouldn't you be unable to ever swap cells if needed, rendering the entire battery useless if lets say there is a critical imbalance between cells or some cells get damaged... couldn't you use just the nickel strips?
Thank you for the tutorial. I'm building a pack of a similar size. Are there any safety risks associated with working with voltages above 50V?
yes, any amount of voltage is dangerous and becomes more dangerous as the voltage increases. always use gloves and take precaution when working with high voltage
Amazing work and amazing music as well
thanks so much! this music is from a great playlist I found on youtube a few years ago - lots of other awesome tracks check it out th-cam.com/video/uL0mvPZuklM/w-d-xo.html
@@GaiusGarage Thanks you are awesome art maker and listener . Keep up the good work always .
If you attach a BMS to your battery pack does that mean that you can charge them from a rectified transformer where you can adjust the dc output voltage to your battery pack ? Like mains ->variac -> transformer -> rectifier -> capacitor -> battery pack. That would be cheap at least for me. Of course with a current limiting resistor between the battery pack and your supply.
you can charge a battery pack with or without a BMS using any constant voltage DC source
There is something called ( prodex ) try for heating
The foam between layers of the pack is a bad idea.
You either want the cells to be in direct contact with each other so that heat from cells at the center of the pack can be conducted outward, or you want to have aiflow through the pack.
Having neither, you increase sag as the inner cells heat up.
Hey man, VERY well done. That battery is overbuilt in the best possible way!
Question for you... I picked up this crazy prototype battery a while back (I work with batteries professionally), and am really curious if its feasible to use it for an e-bike. Coincidentally, its cells are also Samsung 30Q, and this thing was clearly designed to harness the full 15A from each cell (each cell is thermally mated to a liquid cooled aluminum block!!). Here's the thing: the pack is configured as a 24S 12P (86.4V 36Ah) and can't be rearranged. Now, I am familiar with plenty of BMSs and chargers for 24S setups, but I am still mostly an outsider to the e-bike world and am struggling to find compatible parts that are practical and affordable. So I was wondering if you would happen to know of anything like that. I have a 700c road bike I'd like to convert, but I'm open to other ideas too. Also I'm happy to 3d model and print custom parts if need be. Thanks in advance.
The difference between 20s and 24s is pretty small - a lot of overlap in voltage (20s is 84V fully charged, 24s is 86V nominal) so for the most part, you should be able to easily find components that work for both. Basically, the only constraint will be the motor controller - one design for 20s will probably get damaged if connected to 24s fully charged (100.8V). But its easy to find motor controller that will work for 24s -- anything with a max current above 100V will work. I wouldn't worry about the motors - any motor that will work for 20s will also be fine on 24s.
@@GaiusGarage Fantastic. That's great info, thank you so much!
Can you make another vid of your bike. Thanks
Professional build, good job 👍
Everything seems to be well thought of. However, the 8 AWG wire going into the EC8 connector threw me off. Isn't that gauge rated for maximum 45A? what am I missing?
that rating pertains mostly to residential wiring. you can run pretty much any current through any wire, with the factors being voltage drop, length of wire, time the current is applied. for short runs (pretty much anything on an ebike or battery pack) the voltage drop is miniscule even at 200A. if you look up what gauge wire is "rated" for 200A, I would have to use zero gauge, which would be ridiculous
@@GaiusGarage thanks for the thorough response. I appreciate it.
How long is charging time thank you
about 2 hours with a 20A charger
hello I'm building a 20s 9p 90a do you think I need more than 1 .20 nickel strip
Hi. Thanks for this great tutorial video.
I was wondering if its easier to build what you did here using 9v batteries. What are the obstacles that you will come across with building a pack with 9v batteries?
do you mean 9V alkaline batteries like energizer or Duracell?
@@GaiusGarage
I mean the ones that has the positive and negative on one end of the battery, the rectangular looking one.
@@Jay-tr3px for one the typical one you buy at the store are single-use so it would be pretty impractical to build one and throw it in the trash after one use. there are rechargeable versions of these batteries (actually called "PP3") but the capacity on these is pretty low (~0.5Ah) so you would need 84 in parallel & 8 in series (672 total) to get a comperable battery pack. and then they aren't going to have near the discharge capability - pretty much a bad idea all around
@@GaiusGarage
Oh ic.
Thank you for the update.
I would really love to see you do a video on making existing battery packs that comes with ebikes and putting them in series/parallel together and making a higher voltage and range battery pack to use on the same bike or for your own projects.
Thanks again
I’m curious as to how this is a 220A max cont pack when 14 cells in parallel is 210A which each cell having a max cont of 15A , 15A x 14 in parallel is 210A and how does that then have 300A peak discharge can someone elaborate?
I heard solder and high current dont mix well because the solder can potentially heat up enough to liquify under high draw. Any thoughts on this?
Most common solder melts at around 200C - if your connections are heating up this much during use, you've got much bigger problems
why not pack the batteries more tightly?
what a monster !!!! how long does it take to charge !?
@@ioandragulescu6063 depend on the rate of charge. Charging at 1C (40A) would take 1hr. Can be fast-charged at up to 3C (although not the best for cell longevity) and that would take 20 min
Great in-depth video.
Waiting for more.
what would be the maximum charging amps for this battery ?
1C is generally a safe charging rate - this is a 42Ah pack so a good max charge rate would be 42A
Is using 8 AWG for 190A safe?
Do you think it would fit in an Enduro bike frame?
depends what you mean by Enduro frame but if you're talking about the one common frame often referred to as "Enduro", the answer is no. I actually had that frame and sold for the "stealth bomber" frame it to fit this larger battery, and even then it barely fit
How can this battery be utilized as to what i/o needs to be connected to get a 3 prong 110v outlet to power on a microwave, phone, smartphones, tablets, and a solar panel for charging this battery pack...etc... mainly I'm thinkin off grid R.V.
you wouldn't use a battery pack like this for off-grid because the voltage is too high and it was designed for high current draw, which you typically wouldn't need for off-grid. you'll have trouble finding components and will have alot of losses in efficiency. generally off-grid systems use 12V, 24V, or 48V battery systems. youll need an inverter to get AC power from a DC battery like this
Where did you get the foam sheets?
Hi. If I use 4 12 awg copper wire for the positive main discharge would that be able to do the 200 amps continues ? Thanks
four 12awg wires have the about same cross sectional area as one 6awg wire - so yeah should be ok
@@GaiusGarage okay thanks
You can build your own 🚀 t welder easy with transformer
Do you know where I can find this copper strip for series connection for 21700 cells?
not specifically, but Im sure you can find something on aliexpress
nice! I learned a lot about safety!
Hello there how much did the battery 🔋 cost you to make please?
Excellent work. Very nice build.
I cant find the 220 continuos 300A max discharge BMS.
The ones available are 240A continuous but 550A max.
Im usisng 14P sony VTC6 cells so I have max 420A discharge.
Should I go for a lower continuos discharge? Let's say 170 continuous 425A..
Thank you.
you should size your BMS to the peak discharge of what your system will be running
@@GaiusGarage thank you
sir may i know the charger you are using with this huge capacity battery? and can you please share the link too... thank you very much
I would love to build a battery pack to cover the whole height and length of my ruff cycles smyinz but for now I got a triangle bag for a 52v 21a.h 1500w battery to a 72v 3000w hub motor . But like I said would love to build one that fit the whole frame with as many a.h's as possible
That’s what brought me to this video have you upgraded to a good 72v battery yet ? Share the link
@@kaliraah no not yet I'm waiting on a refund from junstar first then I might get one . But never buy a kit from junstar I had a bbso2 for 6months and battery pack that just went one after the other
I'm sure you heard about the sur ron X ! Did you think this battery can fit in the battery caps of the sur ron and it's possible to work with sur ron motor and bac 4000 Controlor ?
it would work with sur ron motor and bac4000 but there's no way this will fit in the battery compartment. maybe if it were arranged differently
why not use lifepo4 for a better discharge rate less cells and complexity and probably cheaper ?
LiFePo4 batteries can't do well in high discharge, not a candidate for high performance needs. They are also 3.2V nominal voltage rated not the 3.6/3.7V nominal so your battery will quit sooner unless you increase the number of series connection in the battery pack.
Sandwiching the copper plate with another piece of nickel or steel works well.
With 21700's available for Ebike battery packs does it make better sense to do a 20S 8P now? Say at 5100mAh & 3.7V/21700 Cell? Or is it that batteries & BMS using 18650's are still way cheaper these days? Is there any weight savings moving up to 21700's for Ebikes with less parallel rows of cells needed in a pack?
it depends on the individual 18650s vs 21700s you're using - you just have to compare two cells types, their capacity, weight, & size
How much was it all up?
Nice build dud, you must post the size of that battery how much would one cost.
dimensions are 325 x 140 x 80 (mm)
Unbelievable work, very helpful video!
one real quick question: does it support fast charge?
fast-charge is more a function of the charger and power supply than the battery. you should not charge any Li-ion battery pack above 3C or so (and that is probably the waay upper limit) its more risky and will ultimately lessen battery life but you can do it if you want to charge as fast as possible. For this battery pack that would be 3 x 42Ah = 126A (like I said, it's a very aggressive charging rate). So at 84V, 126A means you would need to supply 10kW to achieve this level of "fast-charge" and it would fully charge in 10-15min. So if you have a charger connected to a power supply that can provide 10kW, then you can "fast-charge". I'm just charging at home using a standard wall outlet which is limited to 1500W so my upper limit on charging current is about 17A or 0.4C, which is quite low but good for longevity
This is 3 years ago. Can one still buy 18650 li-ion batteries?
How much did all the materials cost in total?
Where do you get the cells. What is the cost. What is description of those cells like voltage is 3.7v but what ah.
Samsung 30Q cells 3Ah - link in the description
How many amps would be this config......??Quick question, I just got a 72v battery pack 20s and believe is 6p, have 120 cells in it (liitokala 5000) but not sure how much amps really is as it doesn't have any labels.