The reason the voltage is sagging soo bad is because of the epoxy!! You can get a cheap spot welder for $50 or less and then weld nickel strip to those 21700s. The copper you are using is great but it's nearly impossible to weld copper to batteries. I promise you though, clean all of that epoxy off those batteries and weld 0.15 or 0.20 nickel strip to those batteries and your scooter will have double the power. Hope this helps!! Take care and be safe. Aaron
It's not the epoxy that is causing voltage sag, the conductivity is several times better than welding. Spotwelding limits the size of contact points between the cell and the nickel strip, causing resistance and heat build-up, a lot of energy gets wasted and result in loss of power and efficiency. Prior to this Samsung 3P battery pack I built and tested a 4P Chinese battery pack and the voltage spike was considerably less than the Samsung 3P setup. Before that I have tried a 16S 1P battery pack and the voltage spiked so much that it was not usable in the scooter. It does not have enough storage of power to handle the load. I explained this in the video.
It's not fun for me to admit but I think you guys are right. My silver epoxy appeared to "deteriorate" and lose connectivity after a month of use. It can't seem to handle high voltage and amp. So my battery stopped working. I had to tear the pack all apart and luckily just two cells got bad. All the rest are fine.. Shit, back to the drawing board.😕 Will look for a battery-powered spot welder as I don't live in electrical grid homes I live in an off-grid shed.
In all fairness your idea of the silver epoxy was brilliant!! Maybe there is some kind of glue or epoxy that can handle the amount current/voltage those beautiful Samsung 21700s put out. I wonder what would happen if you just taped those copper strips in place and really wrapped the battery tight with that packing tape then shrink wrapped it real good? I bet it would last longer than most would think . Probably not a good idea lol. Aaron Binder
We need more ppl like this guy ,honest in what his talking about.this guy dosnt make a video for us to start fires,he makes and shares of the knowledge he knows .good on you bro,
Do u know how to rewire ,hub motors 2000w ,I've try once and nothing happen lol. But I'm about to try my second attempted, ,hope u could maybe advise me as to where I'm going wrong briefly,or I'd love to see a video step by step.keep it up brother
I had a 48v 15ah was only a year old.so I've striped and checked out the battery pack wiring.no power,an not charging .so now I've dismantled batterys bit by bit, checked each one and the fully charged ,so yeH was THE BMS THAT FAILED.,THIS IS MY FIRST build copying what I've seen u do on utube,,thankyou
@user-no8fh6qp9d Do you have two controllers that came with the scooter?.. If that's the case make sure that those 3 phase cables (yellow, green, blue) from the motor are connected to the primary (master) controller and not the secondary controller that is bridged. That should get the motor going.
@user-no8fh6qp9d I am afraid it's not the bms that failed, it is your battery that gone bad from high current charging. Even if the cell is showing the voltage it will hold no charge when put to load.. You'll have to buy new cells.
Using the copper plate is a good idea but instead of epoxy you could have used solder paste, you'd still need a soldinging iron, you can run these using any inverter since you only need 200w max, you are correct that you dont need a bms but you need some ways to monitor the voltage from each cells, the wires you are using looks like 4mm wires which is about 40 amps max. you need 10mm cables.
You can install a fuse, or a breaker to protect from over current to protect the battery from shorts down the line that could happen before the speed controller. You can install a temperature control switch with a probe inside the pack to cut off the power when things get too hot... or even just a temperature display on the handle bar.
And we wonder why there are so many Battery Fires, That Video is a perfect Example on how not to build a battery pack, And this is why we can no longer take E Bikes and Scooters on trains and Buses because of fools who think they know how to build a battery pack with out any safety built in, not even an inline fuse or breaker unbileveble and this is why the goverment clamp down because of fools who want to do cheap short cuts and put everyone els in danger and mess it up for every one at this rate they will be doing a goverment electrical test on all E Bikes and Scooters each year Hope your Proud of yourself, Teaching people on how not to built a Battery Pack.
Don't need no stinkin bms or inline fuse nonsense. You need to stop reading textbook of nonsense the government teaches... When they tell you go kill yourself are you going to say "YES, I COMPLY BY ALL YOUR RULES CAUSE I WORSHIP YOU". Wake da fuck up.
There's nothing wrong with experimenting. How else can we figure out new things. Just be careful that's all. Lithium Batteries can burn your shed to the ground. I really enjoy your videos!! Keep up the hard work!!!! Aaron Binder
It's the characteristics of the cells that you've chosen that give you the significant voltage drop. It's the discharge rate of the cell that matters as well as the number of cells in parallel. The more cells in parallel is not necessarily means less voltage sag. 15 cells in parallel with a discharge rate of 5A aren't necessarily better than 5 cells in parallel each with 20A discharge rate. With the 15 cells in parallel each 5A maximum discharge rate, you will be able to build a battery pack that can discharge 75A maximum. While with the 5 cells in parallel each cell with a discharge rate of 20A, you get 100A maximum of your battery pack. You should have a safety factor though and not use the maximum discharge current totally out of your battery pack. I'm with those who say a BMS is a must in those battery packs. A good design for a battery pack takes into consideration a lot of factors. Thanks for sharing your experience!
You are a long way behind. You are trying to school me something I already know. These are 30A discharge Samsung 40T cells. The culprit of the problem with the voltage drop is the fake silver content in the epoxy. The problem resolved as soon as I used the spotwelding with the nickel strips to ensure reliable electrical connection. And yes the higher number of parallel connections do give more stable power delivery even with cheap Chinese low discharge rate cells.
@@noobz5056Glad that you solved the problem. But still your video is misleading when you say, the higher the parallel connection is the better. While in theory, higher parallel connection will increase the capacity and thus the discharge rate, but that wasn't the problem as you have mentioned with your case. It's not just simply 'more' parallel connections. And please don't mislead inexperienced viewers with not using spot welders or BMS. Using a BMS by far safer to maintain discharge and charge of the battery pack. So your video failed in two ways: you show that you can do it your way without a spot welder, the results weren't successful and two: you said at the end of your video, more parallel connections would solve the voltage sag in your case, obviously, you've said it, it did not.
@@mansoora.7322 If the silver epoxy wasn't fake it would've worked fine on the battery build. The seller and the suppliers' bosses (high level criminals) lied by selling fake silver (and gold too) to the public and they keep the real content in their underground living. God told me that you need enough "physical" battery cells to reduce voltage dip/spike, regardless of the discharge rate of amps of the cells. If you don't have enough cells of parallel connections the voltage dip will be high even with high discharge rate and high capacity cells. Physical number of connections do matter. One of the reasons is due to limitations of the battery cells as they do not have linear power curve. The capacity may be plenty, but the voltage spike will still be high. And you don't need BMS, as long as you are not overvolting the battery pack during charging. They don't do the balance charging, the battery cells in a pack does the self-balancing not the BMS. And you don't need BMS to limit discharge rate, you use smaller controller to draw less amp, to keep the batteries within safe limit.
A lot. 😢 Copper did stay on, but the silver epoxy turned yellow and lost the connectivity. God told me that you and I got ripped off good because the U.S. elites that live in underground cities stole all the silver for themselves and used the leftover impurity, reprocess them to barely meet minimal electrical conductivity needs (PCB boards, which don't require silver content to handle 5V at very low current) and mark up the price for good profit. They got all the good stuff in underground cities near you.
@@noobz5056 By U.S. elites you mean moles or leprechauns ? Come on bro, lay off the crack for a minute would you 😅 (god does not talk to you, nor does he exists and if this fairytale was real I hope he would tackle other topics than your e-scooter battery, it was just a bad design, do your research, good luck for next build 👍)
Enjoyed the video . Can you suggest a reliable seller for the battery cells . I've tried a few people and they were not what they were supposed to be. Thank you
Thanks.🙂 You can get the batteries at bulk-battery.myshopify.com/collections/wholesale-21700-batteries Much cheaper than other google-referred places where they charge you arms and legs for them. *EDIT: AS OF APRIL 5, DO NOT ORDER ANY BATTERIES FROM THE SITE I LINKED ABOVE. The person running this store takes the orders but doesn't ship out.. The phone and email support has cut off. He was trying to steal our money.*
Just use a controller that draws less amps. An 18 - 22 you will not have a problem and have good range with a 72v. If you say the battery is 12a and 30a continuous and your controller is pulling 50a under max load. I have a 60v battery that is 16s8p its 20a and 30a continuous. I use a 30 amp controller no problem and great range. If you are going to over discharge your battery with that load a BMS is a good idea if it has current draw protection.
Ok God told me that you live in offgrid and you are in need of solar panel setup to charge your phone and power all other needs. Get at least one 24V panel or two. Each will cost a little over $200. Get a charge controller for the battery here -> www.aliexpress.us/item/3256805798227949.html?gatewayAdapt=glo2usa Get a 60V battery pack here -> www.amazon.com/Wroyeti-Electric-Extension-Connector-200-1800W/dp/B0BG5G6VW7/ref=mp_s_a_1_3?crid=2TPGF3Z9QJL3N&keywords=60v+scooter+battery&qid=1706720715&sprefix=60v+scooter+battery%2Caps%2C197&sr=8-3&ufe=app_do%3Aamzn1.fos.c3015c4a-46bb-44b9-81a4-dc28e6d374b3 Get an ebike controller to power USB devices here -> www.amazon.com/gp/aw/d/B09FQ52163/ref=ox_sc_saved_image_10?smid=AA5PISMZNU1KS&psc=1 You also need Y split XT60 connector cables to power USB ports. And you need USB ports get them here -> www.aliexpress.us/item/3256804439558261.html?spm=a2g0n.order_detail.order_detail_item.2.41b6f19cTWfNQE&gatewayAdapt=glo2usa and get some 20 gauge wires to connect some wires and heatshrink. If you need help on wiring USB ports watch my videos about powering these devices. Let me know for more questions.🙂
Thanks.. The BMS is unnecessary and can actually have negative impact on the use of battery's charge (decrease range) and they don't even actually balance charge the groups of cells when in fact it is the battery pack itself gets self-balanced with or without the BMS. I will try to make a video of why we don't need BMS as soon as I can. I don't have a good camera to take a video as it doesn't do well in close-ups and focus but I will try to come up with something. 🙂
@@noobz5056 Thank you for this response. Try creating some lighting above the stuff you are filming, it should help with the focus. Maybe a flash light with a see through/transparent bag could do the trick if you're on extreme budget, as the bag should soften the light and not make it so direct like just plain flashlight would, but maybe just the flashlight will do okay. Experiment a little bit with lights, some light source will definitely help you in recording more quality videos. All tho i still appreciate your videos nonetheless. They are informative and easy to understand.
@@ThisIsVeryStupid Thanks...but my camera is an old iPod Touch that is over 12 years old... it actually does better in dimmer light conditions to reduce video noise and artifacts. The near-shot focus is not good due to the limitation of this device. Hoping to get a nice camera soon as I will be posting a lot of videos..
@Pro Danger Gaming YT The battery cells don't catch fire from overcharging. It is not even called overcharging, it is fully charged. Cells don't get hot charging beyond 4.2V, they are designed to receive and hold charge to full, 4.4 or 4.6, if the cell has that storage. The catching of fire will happen if there is short-circuit in the battery you built. It may not do anything... until you start charging, will cause thermal runaway and catch fire, BMS or not. BMS won't protect the batteries when this happens. Watch one of my latest videos titled "Why BMS is Not needed Building Battery Pack".
@@omarsegura2847 Yeah most people trust the science that man has created over the century and abide by it. They like to obey the laws and protocols assuming that is the way in reality it is often wrong and so much they have not discovered... God is the creator and author of truth as he is the one made the electricity and knows how they really work. I appreciate that you give in to consideration or interest wanting to know what is beyond the boundary of limited science. I will try to make a video soon on why we don't need the BMS (in respect to balance charging) when making battery packs for electric vehicles and home use.
I believe the lifepo4 charger charges at lower charging voltage as those batteries nominal voltage is 3.2V and not 3.6. You need to use a regular li-ion battery charger for the 36V battery pack.
Thanks.. I live in a shed off-grid.🙂 Can't wait to get some more money so I can build a 16s 9p battery pack. It will be the same silver paste epoxy copper plate method as it's multiple times better in electrical conductivity and the handling of high current than the nickel strips spot welding.
Yes if you are building a 48V battery pack use a 48V(54.6V full charge) charger. If you have a 60V battery use a 60V charger. Don't use silver epoxy though cause it's fake silver. Just use nickel strip and spot weld..
Thanks for your help ,I love to see more videos of other areas bro ,I've been into electronics for 3 yes just learning from. Utube , every bit from every one helps .thankyou
@user-no8fh6qp9d Mine was a 60V battery build. I found out later that all these silver epoxies aren't real silver content. The epoxy turned yellow after some use, and will kill the battery cells. These epoxy would've been fine for 5V applications. Sorry for the misleading video.
I used the copper as it has the best electrical conductivity and has the headroom for handling much higher amp, to minimize heat, results in clean energy = better efficiency = more power.
You won't be able to find out which cells are bad unless you separate all parallel groups from each other and check the voltages.. Just leave the battery pack alone and use it. Any cells that go bad the other good cells will take over and take the charge/discharge. The bad cells will not hurt the good cells you will just have a small reduction in total battery pack voltage.
Couldn't you have used a 6p configuration by simply turning over the 2nd row of cells and end up with an 8s 6p arrangement? That would have given you the voltage you needed. I ask because I am about to do the same thing. I know it would reduce the run time.
8s would only give me 33.6V (at 4.2V per cell) and that would be too low as my controller's minimum voltage cut-off is 40V.. Plus low voltage is not enough for power...I need a 16s platform.
@@mmills37 Ok thanks. Ok God told me that you can fit 14s 8p in that battery compartment in the Rambler 16.. 21700 not 18650. That would net you 52V system with 58+V full charge. 8p will surely give you that solidity of power/torque with minimal voltage spike.
*Important Disclaimer* This battery pack failed after 1 month of use as the silver content in the silver paste epoxy is fake. It was not real silver nor did it have any purity. Most places carry fake silver so be extremely careful before buying this kind of product. God told me that if this had real content of silver it would have worked fine on the battery build, exceeding the performance you get from pure nickel stripped battery pack in terms of delivering the current in efficient and effective way. Unfortunately God told me you won't be able to get real silver content on these epoxy so just go with the spot welding technique on the pure (or near pure) nickel strip which can be found on internet if you look hard.
I'm not a man. God told me not to remove the video, to expose criminal elites stealing real gold and silver from us and selling the fake ones to us for maximum profit. And ALL places available to the public are fake silver...including silver epoxy.
Don't use silver epoxy as they are fake silver... I got scammed for usin that. You can't find real silver as the criminals underground collect the real stuff.
You don't need no stinkin' BMS...BMS won't balance charge, it's the batteries in a pack that will self-balance. BMS will attempt to discharge and recharge unnecessarily and take you longer time to fully charge. Just make sure that you don't overvolt charging your battery. For 60V battery charge at 67.2V. For a 48V battery charge at 54.6V and so forth. The BMS however will protect you from overvolting (not the same as overcharging), meaning don't use a 67.2V charger on a 48V battery. I buy batteries at bulk-battery.com and the price is better there.
Without him providing any AC IR or DC IR figures this method is suspect. Show lower IR numbers than pure nickel and show a capacity test that probes no degradation (plus the pack has to last a solid 200+ cycles) and I’d be less suspicious about this method.
