JK-BMS in depth review and overview of all settings

This video describes the JK (Jikong) battery management system.
When you saw the video you will be able to select the right BMS for your project.
During the video I go over all the settings and give additional information about the setting. All files are available on my google drive.
DIY 60KWh powerwall built
More information about this and other battery projects: www.easypowerwall.com/
I share my documents, PDF, gerberfiles, circuit diagrams here: www.easypowerwall.com/ click on: parts/tools scroll to bottom of the page.
On this location you can also download the free certificate.
Here's a link to all parts used to built the powerwall:
sites.google.com/view/diy-pow... (adding as we go)
Tools used to during the JK BMS video:
Digital AC/DC clamp meter : s.click.aliexpress.com/e/_Dna... - amzn.to/42om36X
Link to JK BMS V2 I used:
JK-BMS model JK-BxS20S15P : s.click.aliexpress.com/e/_Dls... - amzn.to/3od8Saq
Link the the follow up video with Q&A here: • JK-BMS still on top of...
For recording my YT clips I'm using a DJI pocket: amzn.to/3N7rt26
Disclaimers:
This video is for information purposes only. Be aware building a powerwall is not like making a Bob Ross painting....mistakes can cause large unhappy accidents.
If you have no experience with electrical connections or solar, please contact an experienced technician.

[@tiborchren]

Awesome video with complete comprehensive and useful information. Great job, can't wait to see more videos.

[@Ernest_son]

Good clear explanation. I just ordered 48 cells and was contemplating which brand bms to use. I think you have me leaning toward jk. Thanks for sharing.

[@easypowerwall]

Thanks for nice commente Russel. Good luck with your built.

[@gerdbeutler3728]

Thanks for walking me through the jk setup and the settings spreadsheet. I also didn't receive the one page doc with the BMS. My system is only 3200w inverter, 4800Wh LiFePo4 Battery. To save cost I got only a jk with 80A and 0.6A balancing. I have still a 4A capacity Balancer and will run both at the same starting Voltage. Have installed also a cell meter 8 to have a constant view at my Inverter. The 2 and 4A jk BMS are so costly now. My 80A version was only 50$. Hope to be able to slowly maximize my capacity as I have limits uning only 1440W Solar panels and living in the Highlands of Mindanao, Philippines with more clouds and rain. This is my first solar setup and as a retired electric and IT technician, this project keeps my gray cells busy even at age 71.

[@easypowerwall]

Thanks for the great feedback. We all started with a smaller setup en let the system grow. Keep up the good work and stay healthy and strong to enjoy the green evolutions as long as possible. Franky - EASYPOWERWALL

[@basiceducation1131]

Great information sir, thanks a lot

[@rcasana20001]

very nice video.thank you very much.

[@kostasmonadikos6772]

γεια σου φιλε σε ευχαριστω για το τελειο βιντεο σου με εσωσες

[@alexeykravchenko3870]

really amazing explanation thank you so much

[@easypowerwall]

Alexey thanks for this great comment. These kind of comments keep me going. This weekend new content will be available.....the combinerbox.

[@leah-lithiumionbatterycell24]

Very nice video for JK BMS, I have a new point

[@offgrid2010]

Excellent and very helpful.

[@easypowerwall]

Thanks for nice reaction. Have a great day.

[@ardenbriggs1190]

very good job!!

[@easypowerwall]

Arden, thanks for nice comment. New content is in the making, stay tuned.

[@motardmad8652]

Hi thank you for all the information 👌👌👌 I’m getting a 100amp jk bms for my ebike and I will be getting a bigger controller in the near future but for now can I limit the bms to 70amp output to match my smaller 60amp controller that I currently have .

[@easypowerwall]

Hey, thanks for asking a question. Sure you can limit the maximum current of your BMS. Go to settings and go to advanced settings. Search for "Constinued discharge Current" Enter the desired value. It's in the clip at 19:00. Good luck. Frank Easypowerwall

[@simengineering9183]

Hey Franky, quick question, What would be the settings for a 72v (84v) battery pack built with this. " 26650 Liitokala, model Lii-50A, 5000mAh, 3.7v, max 4.2v, min 2.75v with120 cells I check the xsl file for the BMS parameters and is great to be able to understand what all those settings mean but not sure what should be the parameters to use. great content and well explained! Thanks in advance!!🙏

[@PhilippeCJR]

If you run 2x JK newinverter BMS in parallel, and connect it to Deye (or some other inverter with CANbus), does the SOC be reported in the inverter from the Main BMS, is a mix of pack 1 + pack 2?

[@dominiqueportron338]

Hello Franky, this is really wonderful. Everything is meticulously detailed. I was able to initialize my 2 JKBMS JK-B2A8S-20PC with my 2 12V 280 Amp battery packs, it's great. There is just one small detail, in addition to the Bluetooth on my phone I also have the control screen. (The large model). The batteries are fully charged, but it only shows 78 percent charge. Perhaps this is normal and we will have to wait for the cycles to complete and for the battery and settings to gradually improve. If you could reassure me on this point that would be great. Many thanks again for your video, it’s great. Dominic

[@easypowerwall]

Hey Dominique, thanks for your great comment. To initialize/reset soc of 100%, your cell has to hit the "cell overvoltage protection" If it cycles a few times it will sync and you will get the 100% SOC number. Good luck. Franky

[@cihanbozkir]

Thanks for the video. You mention on/off switch and old/new version at the beginning of the video but I couldn't see it. Did your BMS come with an external on/off switch, did you mean that?

[@easypowerwall]

Hi, check the video 5:45 where I'm gonna push the on/off switch. Older models don't have this swith and you had to apply 5V to start the BMS. If you click on the link under the video to order the BMS you will receive the latest model with switch included. Good luck. Franky - easypowerwall

[@petes-kj2uo]

can you post a link for the the parameter spreadsheet you created? btw great video

[@easypowerwall]

Hey Petes, you can download it here: docs.google.com/spreadsheets/d/1gi-kW6oebZURiijmcprc_71EN35_F0Hs/edit?usp=drive_link&ouid=108566133728311424796&rtpof=true&sd=true

[@petes-kj2uo]

Thank you very much, great video

[@samyuill]

Thank you for this. I have a question. The nominal current is confusing to me. If a battery pack is 48v / 280ah and we have 4 packs = to 1120AH I would need 4 x JKB2A20S ?? -C-H Is the nominal current based on the total AH of the pack so i would need to 500ah version ?

[@easypowerwall]

Hi, My battery bank has 4 16S configurations. I installed a BMS on every 280AH battery (16S) So a 200AH BMS is OK....no need for 500AH bms. Hope this helps.

[@seymourpro6097]

When you have several BMS systems do they talk nicely to you separately, can you interrogate each BMS separately (if they are the same type)?

[@easypowerwall]

Hey Seymour good question. Should have addressed that in the movie. But I can confirm that each BMS works perfectly fine when accessing separately. The application shows all four BMS and you select which one you want to check. No lockups, ne freezes like I once saw on the @TheDigitalMermaid. Will make a BMS follow up movie where I will show how (well) it works.

[@evil17]

User Private Data is where you can add ur own label or name to a system or battery pack BMS and helps you to identify which BMS you are linked to at anytime when u have more than one. I have 2 batteries on a bus setup, so I have labelled them Bus Batt 1 & Bus Batt 2 so I know which one I am connected to.

[@easypowerwall]

Thanks for the information. Will check it out and add it to the follow up video that I'm plannen in the future. Have a nice day. Frank - easypowerall.com

[@rilosvideos877]

Did you ever check the power consumption of the JK-BMS? This is an interesting number as you will typically use this all the time. I found values from a few 100 mW up to 3W and even more. I also found some extremes with 30W and more but i doubt this, probably faulty. Anyway, if its in the 1W+ region it will draw 150 Wh a week or more! Thats already a lot, when the battery just sits idle in a few months (in winter e.g.).

[@easypowerwall]

That's a good question, but never checked this. Good idea for another follow up video about JK-BMS. Stay tuned. Franky

[@CantFindInYoutube]

The reason for the BMS can turn off balance can work like you said to use an external BMS but also to prevent that the BMS discharge the battery since even with BMS power off, balance keeps running, if you have a bad cell you will end with a discharged or lower state of charge and that is not good for an battery in storage.

[@easypowerwall]

Thanks for your reply. Have balancing on from 3.35 (changed setting to 3.4). So when battery is low balancer will not be active and will not drain battery. That's why it's important not to balance all the time, only when voltage is > 3.4V. Have a nice day. Franky - easypowerwall.com

[@CantFindInYoutube]

@@easypowerwall I'm also in 3.4 V and probably will go a bit high.

[@KoiAquaponics]

Hopefully i didn't make a mistake buying 8 of these, gonna put together 8 packs .

[@tiborchren]

I would like to ask how does the JK BMS reset to 100% SOC? When the Cell Over Voltage Protection occurs?

[@easypowerwall]

Yes, that's how it works. It learns from charging. The BMS can't exceed 100%, so it set 100% when max capacity is reached.

[@aureltanasan1413]

Why are you start balance at 3.35v? There’s no benefit of balance anything below 3.4-3.45v, due to the flat curve. Real balance starts when cells are near full. Otherwise you keep shunting current in the flat curve, for no reason.

[@easypowerwall]

Hey Aurel, that's a good point. For now I have it on 3.35 because I haven't done topbalancing (on purpose). I noticed a few cells had less charge then others, so started balancing at 3.35V. In the future I might increase it to 3.4V. Will make a follow up movie 🎬 about this. Thanks again for the feedback.

[@projectv8639]

Hello , first sorry for my English, I have a jk bms ,it is 0.6a of balance ,my battery is lifepo4 60v , 20 cells , but I have 3 of this cells with 3.5v and 17 with 3.3v and the bms cut the charge when one of this 3 cells get de maximum voltage 3.7 approximately and the other 17 cells never get a fully charge, do you thing that the bms itself is capable to balancing this 3 cells that have a bigger voltage? , and what parameter do you think that I have to write in the START VALANCE VOLT .( V ) in the settings, thanks I hope you can help me

[@hammersbald7612]

⁠@@projectv8639 hey, 3.3v means your 17 cells are anywhere between 30 to 60% charged. I wouldn’t want to wait for my BMS to balance 17 cells 😂, could take months. I would either try to top balance them or discharge the 3 full ones down to 3.3v.

[@projectv8639]

@hammersbald7612 ok I would discharge the 3 cells to 3.3 ,is better I think ,thanks

[@nigelcharles511]

Andy's Off-grid garage recommends not to balance below 3.45v to ensure being into the steeper part of the curve. Most specs say max cell voltage is 3.65v not 3.7v.

[@Rabe04]

Do a topbalance at begin and set your start Balance at 3.45V. The OPV must be at 3.64V OVPR 3.6V

[@easypowerwall]

Hey....thanks for your reply. I don't agree with the settings you suggest. I never charge my cells above 3.5V It doesn't make sense....there's only marginal capacity gain. 1% or less. Make sure to read the specs of your batteries.

[@alecks7032]

How does Calibrating Current work? My JK is reading ~30% low at low loads (showing -1.7A when real draw is -3.3A). And about 50% low at high loads (showing -60A when real draw is -110A).

[@easypowerwall]

Mine was spot-on. If it's not correct I suggest to use a clampmeter to measure the current and adjust accordingly. Good luck. Franky - easypowerwall

[@sarwarwali4127]

hi❤ Well, a 3.2 volt 72 ampere lithium ion phosphate battery would use the same parameters.

[@renequintana8921]

Very interesting your video. Congratulations. My question for you is, do you know an app for android or windows whitch let me to get a csv or excel file with individual cell values? in other words, each value read for each cell at one moment, but not just read in graphic mode , i need the value into a file for research purpose. thanks and a Best regards from Argentina

[@easypowerwall]

Don't know by heart, but good question. Maybe it's possible with analog/digital converter + arduino. Challenge is that you need at least 2, preferably 3 digits after the decimal point. If something popsup I will add it to the follow up video. Frank - easypowerwall.com

[@MrSummitville]

​@@easypowerwallDoes the APP have a log file?

[@ardenbriggs1190]

need a video explaining the system log and how to read it...

[@easypowerwall]

OK, thanks for the feedback. Try to check this for the next video about the JK BMS. Make sure to subscribe.

[@rcasana20001]

Sir Pls share the link where you bought the board that contains the 16 fuse. Thank you

[@easypowerwall]

I made it myself. details and download info available here: kzbin.info/www/bejne/hZuTmYyrZqeJeqc

[@MrSummitville]

​@@easypowerwallYou are the only person I know, that fused their BMS wires. What is the anticipated failure mode?

[@patrickruiz6764]

hello I have 2 bms new pcba 200a did you put this kind of bms on your battery?JK-PB2A16S-20P

[@easypowerwall]

Hi Patrick, I am using this model B1A20S15P. Hope this helps. Have a nice day.

[@patrickruiz6764]

hi ok thank you

[@sahilpatildreamer]

I have jk bms 200amp, it worked fine for 30 mins. Then automatically turned off. I tried to wake up as usual with push button but not starting. Tried with 9v battery not starting, also tried with diod mode , no result. I can see little light in push button switch if i hold it. Please help.

[@easypowerwall]

Hi, If you have the model with the push button, then there's no need/use to try the alternative options. The switch should do the trick. Just check that the overal voltage en single voltage is high enough. It might be in hibernation mode because there not enough juice in the battery. Connect a charger (charge slow) and try to boot again. If it's not working, you might have a faulty BMS.

[@1961Timebandit]

you didn't goto the 3rd tab (CONTROL) ... do you or anyone else know how the "Special Charger On" setting works?

[@easypowerwall]

Good idea for the follow up video!

[@basspig]

I have three of these JK bmss and the challenge I have with monitoring them is that I have to go into the room where the power control cabin it is and use my smartphone to read each one. There seems to be no way to extend the Bluetooth range so that I can monitor from another room.

[@easypowerwall]

I understand your frustration. But a BMS is not something you should monitor all the time, we have the shunt to monitor the SOC and the state of battery. It's like monitorring the fuse of you breakerbox, you don't monitor them either. But I'm working on a solution to monitor the BMS, if it works I'll share it with my followers. Have a nice day. Franky

[@tiborchren]

Venus OS or Solar Assistant can be used to monitor basic data from JK BMS from anywhere there is internet.

[@basspig]

@@tiborchren does that run on a PC with bluetooth? I can only monitor one BMS at a time and have been leaving my phone in the battery room linked to Windows until its battery dies. There must be a better option.

[@MistaTerps]

I have my system connected with RJ45 to a Raspberry Pi & sending the information to a web page so I can view it from anywhere. The JK uses RJ45 to communicate. I don’t see why you couldn’t view its information also.

[@basspig]

@@MistaTerps My BMS are inaccessible, physically, without moving a 650lb battery cabinet. I'm looking for a bluetooth solution that would enable me to repeat the signal over a larger distance so I can monitor in another room.

[@hunter8202]

How low should the battery for Lifepo4, fall before recharging? It will be used on a wheelchair. Thank you!

[@easypowerwall]

LifePo4 battery don't have the "memory effect" we know from older type batteries. You can charge whenever you want. In an ideal world I would try to keep my charge between 20 & 80%. If you need the extra energy you can charge to 100% before leaving the house. Hope this helps Franky - EASYPOWERWALL

[@hunter8202]

@@easypowerwall Thank you so much

[@fotoamgamgfoto3695]

hi! I wiredmy 7S70P 18650 setup to a JK BMS. I have a switch with leds to turn it on. It turns on as BT can be connected but status LED on switch button akways RED, cells are at 3.6V each and I only give about 1 Amps to "charge" for test it out. Why is it red status? Whats wrong?

[@easypowerwall]

Hey, the led in the switch is always red. It's there to show the switch, not to indicate a status of the BMS or battery. Hope this helps. Franky - EasyPowerwall.com

[@fotoamgamgfoto3695]

@@easypowerwall thanks! so red is good. It works now since days. The thing I don't find how to measure the real capacity of the battery, I have lots of used cells and only set Ah setting with guesstimation. How can the BMS measure real capacity?

[@basiceducation1131]

Can we use this app in car Android player.please tell.I have made a car with 72v Jk bms 24s

[@easypowerwall]

Yes it is possible. You have to copy the.apk file to car android device and it will work. Will publish new video this week with link to apk file.

[@Cre8ionz.]

When to start and when to stop balancing 18650 Cells ? Do you know the values ?

[@easypowerwall]

I do. Used to have a 14S 240P 18650 powerwall. See www.easypowerwall.com. I used batteries between 3.4 and 4V. Started balancing at 3.9V Good luck. When time is on my side I try to make clip about the 18650 PW.

[@vn04liv]

Hello I'm sorry to bother you but I forgot the custom password I set for bms, how can I do a factory reset, thank you in advance for your reply.

[@easypowerwall]

Have you tried choosing another technology (like LTO)? Ofcourse you have to return to Lifepo4 and enter the correct values again.

[@hunter8202]

battery 24v 100ah charger 20 amperes is it normal or is it very strong ampers?

[@easypowerwall]

Hey, looks normal to me. Power = voltage * amps. In your case 480W = 24V * 20A. Greetings

[@hunter8202]

​@@easypowerwallThank you

[@MrButuz]

So this bms does work with 18650 tesla type packs?

[@easypowerwall]

Yes, 100%

[@MrButuz]

@@easypowerwall OK cool and thanks for the vid.

[@luctessier2215]

How can you change the password when you have forgotten the one you changed?

[@easypowerwall]

Hey Luc, good question for the follow up video. But the answer is pretty simple. When connected to BMS, slide to right towards "settings" where you have to enter your pasword. Now change from technology Li-ion, LTO, ....and this will reset the BMS to factory. Then switch back to the technology you want to use and apply the setting you want to use. Good luck Franky - www.easypowerall.com

[@ivanssatria]

6:24 Can i reset the password? Because i forget it

[@easypowerwall]

Don't know by heart, standard pasword is 1234 or 123456. Will check with JK, If I find a way I'll let you know. I'm planning a second JK-BMS movie.

[@foxeclips9868]

What is password i dont have mannual

[@easypowerwall]

Hey, have you watched the movie? I invest quite a lot of time to create this content. I'm entering the pasword during the movie.....and the manual (one pager) is available as download in the comment section under the video. Franky - easypowerwall

[@SayWhaaaaaaaaaaaaaaaaaaaaaaat]

For me jk bms shows on all cells 0.06v too high voltage and overall for 8cells shows 0.50v higher total voltage. Crappy device

[@MrSummitville]

You got a bad one. That proves nothing. Every manufacturer will have a bad device. Any solution from JK?

[@Richi42]

You need to calibrate into the app!