good job man, first thing first those amazon bms dont do balancing even they say it does :) second thing i think first bms you hooked up was wrong way round and blow the resistors thats why the bms heats up and last thing if you want a long life from your bms just bypass the discharge connection, that way you get more power from you battery and eliminate using discharge function of the bms (less stress for bms ) bms there for only to deliver 4.2v in to blocks equally, if you have bad cells in the pack replacing bms will only be a temporary solution after few cycle of usage the problem will occur again best solution replace the lowest cells when replacing the bms.
Trial an error. Yea first one balance wires were backwards. Didn't see that until after I cooked the board; because I didn't realize they had a 2 way standard.
092422/1639 PST 🇺🇸. Thank you for demo. What was interesting in the video was that, the length of the BMS cables were cut required length. That was the most interesting feature of the video. Thank you again, for demonstrating the idea. There are several postings by RUclips Warriors that “NO NO, THE BMS CABLES must not be cut to required length. The sky will fall down ! (I added this!) The cable can be snipped to required length, readers please understand this. Thank you, Sir, for the ocular proof. Best wishes. 73s…
The e-bike world has a battery problem. That problem is that almost every battery pack, regardless of voltage, is managed by one of these cheapo BMS units, available from eBay and Amazon. Its not a matter of selecting the right unit for your pack, because there is NO right unit for most packs. I say this because I've looked far and wide, and have determined that the only high power battery packs which have suitable BMSs, are ones that were built by the company making the product it goes into. For example, Segway/Ninebot battery packs use a BMS specifically designed for their products. And these BMSs usually have additional connections that allow the BMS to talk to the rest of the EV system, usually through a UART protocol. The cheapo BMSs only do passive balancing, which is fine when the implementation is correct. But most of them only apply around 20mA for balancing. That may be sufficient for a nice, new, already balanced pack, but before long, it won't be. Why? because it's not enough resistance current to prevent high cell banks from continuing to gain voltage when they reach full charge. So once the pack has a couple dozen charge/discharge cycles on it, and the cell banks start to get more unbalanced during use, they may become unbalanced by more than the high voltage cut-off. When this happens on a same-port BMS, the output AND input get disconnected and the pack is now a brick. The only fix is to manually balance the cell banks back to normal so that the BMS can work again. And that situation is actually a better scenario than what is more likely to be the case, which is that the BMS doesn't even have high voltage cut-off for individual banks, and only monitors the total pack voltage. In that case, the high banks just get repeatedly over-charged, which at best will ruin the cells prematurely, and at worst cause a fire. So not only are the cheap BMSs unsafe in that regard, but you can't find one that can sufficiently handle the output current of most ebike packs. You just want a BMS that does what its supposed to do, without you having to think about your battery constantly. And that isn't available. Those cheapo BMS's on eBay and Amazon are only rated usually around 15Amps. You find me a NON-SMART BMS for a 10S li-ion pack that can handle more than 30Amps, and FIT in a typically sized pack, and I'll eat my shorts. I don't want one that interfaces with my phone. I don't want one that costs $100+. I just want one that does its job so I don't have to think about it. And they just don't exist. Quality EV manufacturers like Segway know this, so they design their own BMS that actually works for the life of the battery. Ya know who doesn't design their own BMS? Just about every single ebike company. Like I said, its a problem!
When its high voltage and circuit gets complete it makes a spark, nothing to worry about. Its becouse higher voltage makes longer jump, if you connect it slowly it will jump and create spark but if you connect it fast it wont make it.
The main current passing wires largely depend on how much current you’re going to pull. For, say, 30 amps for a stiff BBS-HD, you want *at least* 10 gauge wire. Thicker wire will reduce the *Ohmic Losses* - less heat, and more mileage. The balance wires will usually be about 20 gauge, as an amp is about as much as most balancing circuits will run, e.g. the Daly “smart” active balancer speaks of 1 Amp. However, there are *SOME* active balancers that will flow as much as 5 amps - and that means 18 gauge or so for their wires.
Thank you! Very helpful video! I got a 13s7p battery, and one of the cells is discharging much faster than the others. Also this cell charges only to 3.5-3.6v, when the others are 4.2v, and the charger light turns green. And when storing this cell once dropped to 1.5v. According to your experience, is it a bad cell or bms? Thank you!
Try to charge just that row and see if it will take a full charge. If not then it's the cells. Battery is only as strong as it's weakest cell. Most bms do a poor job at balancing for what I've seen.
@@Eric_Tennant thank you! I disconnected the bad row, and one cell is losing voltage pretty quickly. From 3.2v to 2.2v in 5 hours. I guess it’s the reason… the other 6 cells keep the same voltage. But they were discharged all the way to 1.5V some time ago which I guess damaged them. Should I replace the whole row or only one cell?
@@Eric_Tennant I ripped off the strip on the positive side, and now I need to solder it back to check? Can I connect only six of them to the strip and leave the bad one disconnected and plug in a charger? I don’t have any imax b6 to check the cells separately.
Not sure. Could work; however the other 12 rows will be lower then 4.2v give the 6p row would be full first and the BMS will stop charging. I used a old 18650 charger from my old vaping days. Your going to need to equal out all cells on that row before adding the missing battery back to it.
Want to find out some good 13/14s BMSes. Ideas? Am thinking that BMSes should be *entirely* connected by anti-spark connectors… seems Amass makes ~ 100 Amp bullet connectors.
Would make for faster swapping if they were sold with bullet connectors. If it the right BMS there will be no spark. I seen while editing this video that both BMS's have B+, B- on the board by the balance wires connection. Oops. The main output wires, some use XT90 anti-spark connectors. At some point I may move to these for better efficiency. Right now I'm using Xt60 with sparks.
@@Eric_Tennant Thank you for the reply. I have a fully charged battery but, when connected to BMS, it does not power on the hoverboard. When I directly connect the battery (~36 volts) to the hoverboard, the hoverboard powers on. I'm fed up with troubleshooting this darn thing and plan to just ride out the charge in the battery, until it's depleted, then throw everything away. Is that safe, as long as I don't charge the battery?
Sounds like a bad BMS or one of the Column of batteries is not charging. You could ride the battery one last time. It will only damage the battery when the voltage goes to low.
So, my 60 volt e-bike and its battery got stolen a couple weeks back, and the other day the police returned it and the battery. Now, rather than charging up to a maximum of 70.3 volts, the BMS is saying that the battery is only a 48 volt battery. Did the thieves give the police the wrong battery, or is the BMS acting up? Not only did the battery come back out of its wrapper, but when I completely unwrapped the battery I noticed that four cells were removed from one end of it. The thieves may have removed the four missing cells, or the battery may have simply came that way from the factory. Not sure
Hi, I have a Kugoo G booster , my voltage is dropping from 51.4 to 0 in seconds . I leave it for few hours then it works like nothing is wrong !! it occurs randomly. Do you think my Bms is damaged ? and after seeing your video i have gone through some bms on amazon but most of them says ≤500w motor and i have two 800w motos so can i use those ? Any answers will be appreciated. Thanks.
100% the BMS is doing that. Ether its bad or it detects the battery is overheating. The only other reason BMS would shut off the discharge is if one of the 13 cells (Columns) drops below 3.6v; however it wouldn't come back until it was charged past that voltage again. I am currently using Daly BMS in my packs for my 48v amzn.to/3mxLvYh
@@nafi.j Yea. a 30ah bms would work (54.6v x 30ah = 1638wh). So long as that scooter allows for any bms to be used. Daly takes its own plug so the balance wires would have to be replaced for that brand ruclips.net/video/zhymnU83Jlo/видео.html . Also if battery is overheating this wont fix it.
@5:59 Excuse me, thats my title. If there was a bomb with an hour left on the timer, and I have soldering iron already plugged in, solder, flux, and only needed to solder 1 wire to the board, we’re all going to die.
I just made a 6s4p battery pack but my bms is not responding at all it's a balanced one with negative wire going to bms for protection but negative is not responding on other side i spent about 13 dollars on it it's a china one
@@Eric_Tennant thanks for your reply I am just sitting here and trying to get a response on a professional but you replied thanks and I did what you said yes 1 of the cell is 2.5 v and I removed it now I have to spot weld the replace battery
@@malindurajapaksha1791 Helps to have them all charged to 4.2v before linking them to prevent adding dead cells. Most BMS balancing features lack the amps to fix a out of balanced battery. I added a Neey cable to all of the batteries I have to keep them maintained and balanced. ruclips.net/video/zMOUt7dSupM/видео.html Be safe!
@@Eric_Tennant it's all new from Sony 1 battery was like 12 dollars but I bought 50 of them. Update now it's working. so that mean the China bms is good? Now I am discharging All of them because I didn't sure about these batteries they are original Sony batteries but you know can't trust anything now days
i dont do bms's I only charge with custom batteries i made with balance cables and hobby charger that shows all the cells voltages on a display can't trust the red/green light of a bms... I had 4 ebike batteries from Amazon fail....
I have to say for someone new to ebikes you sure know your electric stuff. Just curious on how and why. I also share a lot of hobbies that you do, like all the ebike stuff. If your ever in Boulder Colorado lets ride and sing ole songs!
I think im gonna buy a rc hobby bms so then u can see what sell is doing what from that bms cable also u can charge the individual packs to 3.7 so it ballances it so u dont have 2 take em appart that far i think after many video's thats the safest smartest and quickest way but my bms is locked out so i have 2 solder a New bms to it then ballance so the bms is detecting that all is good what a work but this is a handy video what not to do 😂
ruclips.net/video/eQ1FLXeUgWw/видео.htmlsi=c__onTQzQnm5SSDy then im gonna do what this guy is doing with your soldering directions wish me luck maybe its smart to film it as well because battery fire video's are doing well as we😂
Thats nice i just have the bike 2 days its almost brandnew saved from the scrapper im gonna look that video its nice to learn from People Who tried stuf instead of reinventing the wheel yourself and when People share knowledge its a huuge plus
🛒BMS: amzn.to/3KwOAPE
🛒in line Meter: amzn.to/3nM6N28
🛒Multimeter: amzn.to/3PdFDgQ
🛒Solder Iron Kit: amzn.to/3W51BFl
🛒Solder: amzn.to/3g33HTf
🛒5v Buck: amzn.to/3tLH2mn
good job man, first thing first those amazon bms dont do balancing even they say it does :) second thing i think first bms you hooked up was wrong way round and blow the resistors thats why the bms heats up and last thing if you want a long life from your bms just bypass the discharge connection, that way you get more power from you battery and eliminate using discharge function of the bms (less stress for bms ) bms there for only to deliver 4.2v in to blocks equally, if you have bad cells in the pack replacing bms will only be a temporary solution after few cycle of usage the problem will occur again best solution replace the lowest cells when replacing the bms.
Trial an error. Yea first one balance wires were backwards. Didn't see that until after I cooked the board; because I didn't realize they had a 2 way standard.
092422/1639 PST 🇺🇸. Thank you for demo. What was interesting in the video was that, the length of the BMS cables were cut required length. That was the most interesting feature of the video.
Thank you again, for demonstrating the idea. There are several postings by RUclips Warriors that
“NO NO, THE BMS CABLES must not be cut to required length. The sky will fall down ! (I added this!)
The cable can be snipped to required length, readers please understand this.
Thank you, Sir, for the ocular proof. Best wishes. 73s…
Would need to be a truck sized battery before length would matter that much.
If and when you do this again, try using a dremel tool with cut off wheel, to reduce risk of shorting out.
The e-bike world has a battery problem. That problem is that almost every battery pack, regardless of voltage, is managed by one of these cheapo BMS units, available from eBay and Amazon. Its not a matter of selecting the right unit for your pack, because there is NO right unit for most packs. I say this because I've looked far and wide, and have determined that the only high power battery packs which have suitable BMSs, are ones that were built by the company making the product it goes into. For example, Segway/Ninebot battery packs use a BMS specifically designed for their products. And these BMSs usually have additional connections that allow the BMS to talk to the rest of the EV system, usually through a UART protocol.
The cheapo BMSs only do passive balancing, which is fine when the implementation is correct. But most of them only apply around 20mA for balancing. That may be sufficient for a nice, new, already balanced pack, but before long, it won't be. Why? because it's not enough resistance current to prevent high cell banks from continuing to gain voltage when they reach full charge. So once the pack has a couple dozen charge/discharge cycles on it, and the cell banks start to get more unbalanced during use, they may become unbalanced by more than the high voltage cut-off. When this happens on a same-port BMS, the output AND input get disconnected and the pack is now a brick. The only fix is to manually balance the cell banks back to normal so that the BMS can work again. And that situation is actually a better scenario than what is more likely to be the case, which is that the BMS doesn't even have high voltage cut-off for individual banks, and only monitors the total pack voltage. In that case, the high banks just get repeatedly over-charged, which at best will ruin the cells prematurely, and at worst cause a fire.
So not only are the cheap BMSs unsafe in that regard, but you can't find one that can sufficiently handle the output current of most ebike packs. You just want a BMS that does what its supposed to do, without you having to think about your battery constantly. And that isn't available. Those cheapo BMS's on eBay and Amazon are only rated usually around 15Amps. You find me a NON-SMART BMS for a 10S li-ion pack that can handle more than 30Amps, and FIT in a typically sized pack, and I'll eat my shorts. I don't want one that interfaces with my phone. I don't want one that costs $100+. I just want one that does its job so I don't have to think about it. And they just don't exist. Quality EV manufacturers like Segway know this, so they design their own BMS that actually works for the life of the battery. Ya know who doesn't design their own BMS? Just about every single ebike company. Like I said, its a problem!
When its high voltage and circuit gets complete it makes a spark, nothing to worry about. Its becouse higher voltage makes longer jump, if you connect it slowly it will jump and create spark but if you connect it fast it wont make it.
Buen trabajo! Estoy seguro que estos dispositivos, como la mayoría, salen la factoría con obsolescencia programada.
Solo tomaría un condensador para cronometrar su final.
Hi sir I'm build one battery back 10s8p I already to connect everything but I confused bms wire which size are using so please help me
Not sure what you are asking.
The main current passing wires largely depend on how much current you’re going to pull. For, say, 30 amps for a stiff BBS-HD, you want *at least* 10 gauge wire. Thicker wire will reduce the *Ohmic Losses* - less heat, and more mileage.
The balance wires will usually be about 20 gauge, as an amp is about as much as most balancing circuits will run, e.g. the Daly “smart” active balancer speaks of 1 Amp.
However, there are *SOME* active balancers that will flow as much as 5 amps - and that means 18 gauge or so for their wires.
What part number ended up working?
Here is the current repair / upgrade I do to all my batteries. ruclips.net/video/rXX4FNvY6hk/видео.html . The BMS from this video was removed.
Thank you! Very helpful video! I got a 13s7p battery, and one of the cells is discharging much faster than the others. Also this cell charges only to 3.5-3.6v, when the others are 4.2v, and the charger light turns green. And when storing this cell once dropped to 1.5v. According to your experience, is it a bad cell or bms? Thank you!
Try to charge just that row and see if it will take a full charge. If not then it's the cells. Battery is only as strong as it's weakest cell.
Most bms do a poor job at balancing for what I've seen.
@@Eric_Tennant thank you! I disconnected the bad row, and one cell is losing voltage pretty quickly. From 3.2v to 2.2v in 5 hours. I guess it’s the reason… the other 6 cells keep the same voltage. But they were discharged all the way to 1.5V some time ago which I guess damaged them. Should I replace the whole row or only one cell?
Just the bad cell I would think. Does the 6 cells charge to 4.2v when the bad one is removed?
@@Eric_Tennant I ripped off the strip on the positive side, and now I need to solder it back to check? Can I connect only six of them to the strip and leave the bad one disconnected and plug in a charger? I don’t have any imax b6 to check the cells separately.
Not sure. Could work; however the other 12 rows will be lower then 4.2v give the 6p row would be full first and the BMS will stop charging. I used a old 18650 charger from my old vaping days. Your going to need to equal out all cells on that row before adding the missing battery back to it.
Hi, where did you get the voltage checker?
🛒Meter: amzn.to/3nM6N28
🛒Multimeter: amzn.to/3PdFDgQ
@@Eric_Tennant thank
Anytime
Want to find out some good 13/14s BMSes. Ideas?
Am thinking that BMSes should be *entirely* connected by anti-spark connectors… seems Amass makes ~ 100 Amp bullet connectors.
Would make for faster swapping if they were sold with bullet connectors. If it the right BMS there will be no spark. I seen while editing this video that both BMS's have B+, B- on the board by the balance wires connection. Oops.
The main output wires, some use XT90 anti-spark connectors. At some point I may move to these for better efficiency. Right now I'm using Xt60 with sparks.
I’m currently using the -90 connectors for output, -60 for charging.
Note: I’m thinking my B.M.S. has *ex-pired.* Zero volts out…
Addendum to previous: seems the 60 Amp (RED) Daly (Smart) BMS has *6mm screws!* for connectors!
Can I connect the battery directly to the hover board, bypassing the BMS?
Yes; however then the battery has zero safety features. You basically need low voltage shutoff when using it. Many Bikes/boards do this already.
@@Eric_Tennant Thank you for the reply. I have a fully charged battery but, when connected to BMS, it does not power on the hoverboard. When I directly connect the battery (~36 volts) to the hoverboard, the hoverboard powers on.
I'm fed up with troubleshooting this darn thing and plan to just ride out the charge in the battery, until it's depleted, then throw everything away. Is that safe, as long as I don't charge the battery?
Sounds like a bad BMS or one of the Column of batteries is not charging. You could ride the battery one last time. It will only damage the battery when the voltage goes to low.
I have the same battery and everything. Even the packaging is the same.
It’s mandatory that, while replacing and or performing any kind of repairs; the Battery must be disconnected.
Always a good idea when possible.
So, my 60 volt e-bike and its battery got stolen a couple weeks back, and the other day the police returned it and the battery. Now, rather than charging up to a maximum of 70.3 volts, the BMS is saying that the battery is only a 48 volt battery. Did the thieves give the police the wrong battery, or is the BMS acting up? Not only did the battery come back out of its wrapper, but when I completely unwrapped the battery I noticed that four cells were removed from one end of it. The thieves may have removed the four missing cells, or the battery may have simply came that way from the factory. Not sure
Sorry to hear that. Don't think it the bms. They did something to it.
Hi, I have a Kugoo G booster , my voltage is dropping from 51.4 to 0 in seconds . I leave it for few hours then it works like nothing is wrong !! it occurs randomly. Do you think my Bms is damaged ? and after seeing your video i have gone through some bms on amazon but most of them says ≤500w motor and i have two 800w motos so can i use those ? Any answers will be appreciated. Thanks.
100% the BMS is doing that. Ether its bad or it detects the battery is overheating. The only other reason BMS would shut off the discharge is if one of the 13 cells (Columns) drops below 3.6v; however it wouldn't come back until it was charged past that voltage again.
I am currently using Daly BMS in my packs for my 48v amzn.to/3mxLvYh
@Eric Tennant thank you.
@@Eric_Tennant but do you think changing the bms would solve the problem?
@@nafi.j Yea. a 30ah bms would work (54.6v x 30ah = 1638wh). So long as that scooter allows for any bms to be used. Daly takes its own plug so the balance wires would have to be replaced for that brand ruclips.net/video/zhymnU83Jlo/видео.html .
Also if battery is overheating this wont fix it.
@Eric Tennant thanks mate.. I have zero experience with this but I'll give it a go let's see what happens.
@5:59 Excuse me, thats my title. If there was a bomb with an hour left on the timer, and I have soldering iron already plugged in, solder, flux, and only needed to solder 1 wire to the board, we’re all going to die.
I just made a 6s4p battery pack but my bms is not responding at all it's a balanced one with negative wire going to bms for protection but negative is not responding on other side i spent about 13 dollars on it it's a china one
Double check to make sure the balance wires are in the right order. Also check If any rows are under 3.0v. If not them you may of got a bad BMS.
@@Eric_Tennant thanks for your reply I am just sitting here and trying to get a response on a professional but you replied thanks and I did what you said yes 1 of the cell is 2.5 v and I removed it now I have to spot weld the replace battery
@@malindurajapaksha1791 Helps to have them all charged to 4.2v before linking them to prevent adding dead cells. Most BMS balancing features lack the amps to fix a out of balanced battery.
I added a Neey cable to all of the batteries I have to keep them maintained and balanced. ruclips.net/video/zMOUt7dSupM/видео.html Be safe!
@@Eric_Tennant it's all new from Sony 1 battery was like 12 dollars but I bought 50 of them. Update now it's working. so that mean the China bms is good? Now I am discharging All of them because I didn't sure about these batteries they are original Sony batteries but you know can't trust anything now days
@@malindurajapaksha1791 Nice happy its working now. The bms was doing it's job as far as low voltage disconnect goes.
Subscribe www.youtube.com/@Eric_Tennant?sub_confirmation=1
Battery still going strong: ruclips.net/video/1RFBhYJiAhE/видео.html
i dont do bms's I only charge with custom batteries i made with balance cables and hobby charger that shows all the cells voltages on a display can't trust the red/green light of a bms... I had 4 ebike batteries from Amazon fail....
I have found that BMS do a poor slow job a balancing. I do need to get a hobby charger at least to make fixing them easier.
I have to say for someone new to ebikes you sure know your electric stuff. Just curious on how and why. I also share a lot of hobbies that you do, like all the ebike stuff. If your ever in Boulder Colorado lets ride and sing ole songs!
Thanks. My wife says I need lots of hobbies so I don't drive her nuts. Will do when ever I can get up there again, I love Colorado.
How To Upgrade Electric Bike Battery to Solar Battery ruclips.net/video/rXX4FNvY6hk/видео.html
Well, all my batterys from china had all black wires :D
Перевод какой-то непонятный
Язык смешной такой
I think im gonna buy a rc hobby bms so then u can see what sell is doing what from that bms cable also u can charge the individual packs to 3.7 so it ballances it so u dont have 2 take em appart that far i think after many video's thats the safest smartest and quickest way but my bms is locked out so i have 2 solder a New bms to it then ballance so the bms is detecting that all is good what a work but this is a handy video what not to do 😂
ruclips.net/video/eQ1FLXeUgWw/видео.htmlsi=c__onTQzQnm5SSDy then im gonna do what this guy is doing with your soldering directions wish me luck maybe its smart to film it as well because battery fire video's are doing well as we😂
I use a external system to balance the battery now. ruclips.net/video/zMOUt7dSupM/видео.html
Thats nice i just have the bike 2 days its almost brandnew saved from the scrapper im gonna look that video its nice to learn from People Who tried stuf instead of reinventing the wheel yourself and when People share knowledge its a huuge plus