Thanks for a clear, easy-to-understand video. I picked up some 2S boards on ebay with their hookup diagram but your treatment with the soldering, nickel strip, captan, silicone, testing, etc. is a very nice demonstration. Very helpful for others!
a pretty impressive vid. clear, well explained and interesting vid. it always amazes me where you guys get your knowledge. when i watch these vids i am always saying WHERE DID HE LEARN THAT FROM, OR THATS COOL. but anyway now im a bit wiser. so thanks
Those little bms's are good for low-end applications, but can't compete with a balance wire and a good hobby grade balance charger, when reliability of the battery pack is a priority.
I agree, as most viewers know I use my Tenergy charger for most packs on my bench. Of course, as mentioned, this was for a friends dog collar. Still needs proper charger of course.
I like this video instruction a lot. Very clear and THANK YOU, no annoying music. Can you tell me how you determine when your 2S pack is fully charged? Is there some way to include an LED indicator if there are no space restrictions? Thanks for posting the links too.
Thanks for your comment, the cut off for a 2s pack is around 8.4V. you just don't want to go above 4.2V on a cell. With the BMS connected and charging through it, it should cut out at around 8.4V and the ps current will show zero.
Very clear video. I'm going to make a 2S2P battery pack soon. Is it safe to charge the batteries giving power to the BMS? Someone told me the good way is to use a balanced charger
Balance charger is best for sure. I have had great success with these building cheap packs for lots of toys or specialty devices and it works fine and you have really good protection with most of these BMS. Overcharge and the undervoltage cut out are the main things for me.
Building battery pack using 18650 for 7.2v 35w 1.4ah, do u recommend using 2 batteries in parallel and connect them to another pair in series? This way boost up amps which give better torque used in power drill?
Yes using 2P-2S is the way to go with higher current drains as long as no size limitations of course. In my case it was just size limitations and of coarse very little drain. Have fun!
Well yes the 2S is a common setting for most hobby Li-Po chargers and I have used mine for these, but I almost always use my bench top PS set for 8.3V CV and around 1A CC. The CV and CC method is awesome.
how much current and volts should i gave it the pack? or do i have use another thing to give it constant current then constant voltages? is there a small circuit that can do that? i am confused there.
I always use a CC-CV supply. I set my Power supply for 1A max current and voltage set to 8.4V for the 2S packs. (Two 18650 in series) you could use a hobby type charger or any other CC-CV source like the Drok DC-DC Converters I have shown in some videos would work also.
Hello and thank you for the video! I’m trying to use the same board to build a battery pack but with 26650 cells and it is outputting current only when I connect the cells to the P+ and P- instead of the B+ and B- . Should I use 18650 cells or am I missing something?
Hello, I have used a couple of these with no issues. I have the cells together on one end + to - then other ends connected to B+ and B- and I do have to charge it through P+ and P- first before it will output the first time or after a serious fault. so P is for charging and output on mine. Hope it helps. Best of luck!
hello I want to increase the capacity so is it possible to connect 2 in series and another 2 in series and join them both in parallel and connect them to the bms? Subbed
Yes I can explain very easy. The connector wires were connected to the P+ and P- as explained. The last step in soldering was the cells to the B+ and B- which was also mentioned.
Thank you for the video with your clear explanation. May I know what is the name of the 2s bms circuit board and does it have cell balancing and over current auto recovery?
Yes, as a test with the current set to 1.1A and the voltage set around 12V to test if over voltage would shut down. I would not charge it this way of course. Only a test. With a CC supply it actually charged ok because once the current dropped off enough for Voltage to climb, it was very close to fully charged when the voltage showed above 8.5V or so and it shut off.
Also why use nickle as a connector. why not use copper wire? Isnt copper a more efficient conductor. Will you get differential corrosion with copper? I have lots of copper laying around thats why i ask.
Yes, if you are not familiar or comfortable soldering on cell you can always solder on to some tabs first and then spot weld the tabs on the cells! I just keep some tabs or nickel strips around for that...
I would go to at least 8.6 to 9V In for loss in the small wires and circuitry. if your leads are not long, you may charge up really close to fully charged with the 8.4V.
Thank you for sharing your knowledge to educate viewers. I have a question, i want to use 2s BMS with 7.4v in my demo project along with solar panel charging/DC adapter, My question is how can i use charging from solar to these cells and at the same time provide voltage to my Arduino board out of these cells. Remember solar is 9V and i require (7 to 7.4) volt on Arduino board. could you please assist me how battery pack (Made in your video) connection will work with my scenario? I am not sure which BMS pin should be used to power arduino at the same cells are being charged.
Bro I have the same BMS board it is cutting off voltage just as my batteries discharge to 3.7V. Could you plz tell me the mistake I am making or solution for this problem?
@@geethanshr I would not think so, unless it is such a large current that it shuts down? Like for over current protection. If not and you have double checked the connections are correct, you could have a bad board. I have used 3 of these and have not had that same issue!
@@ThriftyToolShed thank you so much. I guess my modem requires more current hence it shuts down by over current protection. So if it has more voltage then it can work for large current? And shuts down at 3.7V. What is the max amps it can give out?
I can't get these to work for the life of me. Your video was awesome I connected bm first then pos and neg of battery and no power is coming out of p- and p+. Please advice.
You do have to charge on most BMS the initial charge is like activations and also if a fault condition such as short circuit etc. You will have to give charge to turn back on!
Thrifty Tool Shed , thanks a lot for your swift reply. I about gave my self a gash on my noggin trying to figure this out. Maybe what you suggested applies to this board only. I've made 3s up to 6s batteries and BMS work right away. I will surely give this booger a try. So I need to wire the p- and p+ and connect it to a charger that puts out 9 volts at 1.2amps? Then I will get power voltage? Thanks
I forgot to mention. Where exactly did you connect the MB to on you batteries. I connected mine on the negative of the series connection. I figure its OK since both batteries are joined with a fuse wire.
I used a 3mm strip for my application. I have lots of these strips around from different BMS boards over the years. You have to pick strip or wire suitable for your current draw. At least the proper rating of your BMS board.
Easiest way is go to the link in video description for the BMS and select the 2S BMS board and it is a diagram on there of cells and board connections.
That's why they keep exploding! As mentioned in many of my videos if you prefer spot welding, do so! I have done mine for years and have over 25 years experience with electronics, I have never, never, had an issue. Thanks for your concern and comment.
Thanks for a clear, easy-to-understand video. I picked up some 2S boards on ebay with their hookup diagram but your treatment with the soldering, nickel strip, captan, silicone, testing, etc. is a very nice demonstration. Very helpful for others!
So glad, thanks so much for your comment!
@@ThriftyToolShed dude you should put balance lead so it balnce the cells
I am glad you said that the balance circuit is dead at first until it gets its first charge from adapter. I thought my BMS was broken.
Absolutely and it will do the same thing at cut off level or over current condition!
a pretty impressive vid. clear, well explained and interesting vid. it always amazes me where you guys get your knowledge.
when i watch these vids i am always saying WHERE DID HE LEARN THAT FROM, OR THATS COOL.
but anyway now im a bit wiser. so thanks
Those little bms's are good for low-end applications, but can't compete with a balance wire and a good hobby grade balance charger, when reliability of the battery pack is a priority.
I agree, as most viewers know I use my Tenergy charger for most packs on my bench. Of course, as mentioned, this was for a friends dog collar. Still needs proper charger of course.
I like this video instruction a lot. Very clear and THANK YOU, no annoying music. Can you tell me how you determine when your 2S pack is fully charged? Is there some way to include an LED indicator if there are no space restrictions? Thanks for posting the links too.
Thanks for your comment, the cut off for a 2s pack is around 8.4V. you just don't want to go above 4.2V on a cell. With the BMS connected and charging through it, it should cut out at around 8.4V and the ps current will show zero.
I don't thinck the protection board has a cell balance function? Pack can then become unbalanced over time.
Very clear video. I'm going to make a 2S2P battery pack soon. Is it safe to charge the batteries giving power to the BMS? Someone told me the good way is to use a balanced charger
Balance charger is best for sure. I have had great success with these building cheap packs for lots of toys or specialty devices and it works fine and you have really good protection with most of these BMS. Overcharge and the undervoltage cut out are the main things for me.
Building battery pack using 18650 for 7.2v 35w 1.4ah, do u recommend using 2 batteries in parallel and connect them to another pair in series? This way boost up amps which give better torque used in power drill?
Yes using 2P-2S is the way to go with higher current drains as long as no size limitations of course. In my case it was just size limitations and of coarse very little drain. Have fun!
how are you gonna charge this 2S BMS? I dont think we have 8.4V Chargers available in the markets?
Well yes the 2S is a common setting for most hobby Li-Po chargers and I have used mine for these, but I almost always use my bench top PS set for 8.3V CV and around 1A CC. The CV and CC method is awesome.
Hello! After I added PCB protection board to a 18650 battery, now it won't charge! Do you know what may be the reason? Thank you!
I have not had that issue. If wired correctly it should charge as usual.
how much current and volts should i gave it the pack? or do i have use another thing to give it constant current then constant voltages? is there a small circuit that can do that? i am confused there.
I always use a CC-CV supply. I set my Power supply for 1A max current and voltage set to 8.4V for the 2S packs. (Two 18650 in series) you could use a hobby type charger or any other CC-CV source like the Drok DC-DC Converters I have shown in some videos would work also.
Hello and thank you for the video!
I’m trying to use the same board to build a battery pack but with 26650 cells and it is outputting current only when I connect the cells to the P+ and P- instead of the B+ and B- . Should I use 18650 cells or am I missing something?
Hello,
I have used a couple of these with no issues. I have the cells together on one end + to - then other ends connected to B+ and B- and I do have to charge it through P+ and P- first before it will output the first time or after a serious fault. so P is for charging and output on mine. Hope it helps. Best of luck!
hello I want to increase the capacity so is it possible to connect 2 in series and another 2 in series and join them both in parallel and connect them to the bms? Subbed
Yes, you are limited by current rating of the BMS you decide to buy. But yes a 2S2P pack is possible with this board.
The battery + and battery - should be wired to B+ and B-. But you have wired them to P+ and P-. could you explain why?
Yes I can explain very easy. The connector wires were connected to the P+ and P- as explained. The last step in soldering was the cells to the B+ and B- which was also mentioned.
Thank you for the video with your clear explanation. May I know what is the name of the 2s bms circuit board and does it have cell balancing and over current auto recovery?
Did I get this correct? you charged this 2S pack with 13V and it was ok? There is no step down converter built in this protection board, right?
Yes, as a test with the current set to 1.1A and the voltage set around 12V to test if over voltage would shut down. I would not charge it this way of course. Only a test. With a CC supply it actually charged ok because once the current dropped off enough for Voltage to climb, it was very close to fully charged when the voltage showed above 8.5V or so and it shut off.
Also why use nickle as a connector. why not use copper wire? Isnt copper a more efficient conductor. Will you get differential corrosion with copper? I have lots of copper laying around thats why i ask.
Actually, the strips came with some of the BMS boards I have ordered and I have used the copper wire before as well.
Do I connect balance cable to the output of protection circuit or directly to the cells?
Yes, if you are not familiar or comfortable soldering on cell you can always solder on to some tabs first and then spot weld the tabs on the cells! I just keep some tabs or nickel strips around for that...
What voltage do I need to charge the two batteries with this board? 8.4V is enough?
I would go to at least 8.6 to 9V In for loss in the small wires and circuitry. if your leads are not long, you may charge up really close to fully charged with the 8.4V.
Thank you for sharing your knowledge to educate viewers. I have a question, i want to use 2s BMS with 7.4v in my demo project along with solar panel charging/DC adapter, My question is how can i use charging from solar to these cells and at the same time provide voltage to my Arduino board out of these cells. Remember solar is 9V and i require (7 to 7.4) volt on Arduino board. could you please assist me how battery pack (Made in your video) connection will work with my scenario? I am not sure which BMS pin should be used to power arduino at the same cells are being charged.
yes u can
Bro I have the same BMS board it is cutting off voltage just as my batteries discharge to 3.7V.
Could you plz tell me the mistake I am making or solution for this problem?
I have not had that issue. So both cells are at 3.7 when it cuts out?
@@ThriftyToolShed ya...are the cells discharging too fast?
@@geethanshr I would not think so, unless it is such a large current that it shuts down? Like for over current protection. If not and you have double checked the connections are correct, you could have a bad board. I have used 3 of these and have not had that same issue!
@@ThriftyToolShed thank you so much.
I guess my modem requires more current hence it shuts down by over current protection.
So if it has more voltage then it can work for large current? And shuts down at 3.7V.
What is the max amps it can give out?
It's possible, but I would not think a modem would pull that much though? I guess I would double check the true current draw to be sure?
I can't get these to work for the life of me. Your video was awesome I connected bm first then pos and neg of battery and no power is coming out of p- and p+. Please advice.
You do have to charge on most BMS the initial charge is like activations and also if a fault condition such as short circuit etc. You will have to give charge to turn back on!
Thrifty Tool Shed , thanks a lot for your swift reply. I about gave my self a gash on my noggin trying to figure this out. Maybe what you suggested applies to this board only. I've made 3s up to 6s batteries and BMS work right away. I will surely give this booger a try. So I need to wire the p- and p+ and connect it to a charger that puts out 9 volts at 1.2amps? Then I will get power voltage? Thanks
I forgot to mention. Where exactly did you connect the MB to on you batteries. I connected mine on the negative of the series connection. I figure its OK since both batteries are joined with a fuse wire.
@@milvolts1 yes, it should.
Thrifty Tool Shed , It worked! You are a lifesaver. Cheers🍻
Wouldn't it be a lot better skipping the BMS and using a spot welder instead of soldering these together? Cheaper, faster, more reliable.
That is a helluva southern accent you have there. Where in the deep south you be at?
Augusta, Georgia! I can't hide it...🤣
@@ThriftyToolShed I knew I heard a true deep south Georgia accent. :)
what size of nickle strip?
I used a 3mm strip for my application. I have lots of these strips around from different BMS boards over the years. You have to pick strip or wire suitable for your current draw. At least the proper rating of your BMS board.
What type of flux did you use to solder to the battery terminals?
Rosin
RA flux, basically it is pine rosin. It is sticky but works well and cleans up easy with alcohol.
Thank you.
Can I get circuit diagram for this??
Easiest way is go to the link in video description for the BMS and select the 2S BMS board and it is a diagram on there of cells and board connections.
You seem to keep the soldering iron on it too long. That’s dangerous.
That's why they keep exploding! As mentioned in many of my videos if you prefer spot welding, do so! I have done mine for years and have over 25 years experience with electronics, I have never, never, had an issue. Thanks for your concern and comment.
I want this pair of battery 5000mah