Before replacing, make sure that the voltage of the new battery and the old battery are the same. It is recommended to use CELL of the same capacity. Step: www.yousun.org...
Nice tutorial. I just rebuilt a pack for a Compaq Contura Aero that has a similar configuration (thankfully no BMS on these dinosaurs) but I had a hard time keeping the cells together during assembly. After watching your tutorial, things will be far easier and prettier for other builds.
Thanks Yousum, I appreciate the feedback. When you say "make sure that the voltage of the new battery and the old battery are the same" do you mean the entire battery or the cell I'm replacing please? I haven't opened my battery yet but I understand it to be 3 groups of either 2 or 3 cells connected in parallel. I plan to use replacement cells of the same capacity as original. I plan to replace one cell in each parallel unit at a time. I will measure the voltage of the parallel unit and adjust the voltage of the replacement cell to match. I may also connect the new cell to the parallel unit where it will be installed to ensure charge has equalized. I will then remove one cell from the parallel unit, leaving the other 1 (or 2) still connected and replace it with a new one. I am assuming that the BMS monitors the charge state of each individual parallel unit and not each individual cell so removing one cell from unit shouldn't decrease the voltage, just the amperage? So the BMS fuse shouldn't be activated? Am I close?
Going to rebuild a chinese pack tomorrow as 2 cells had 0v and being damaged. Rest was 3.4v which is alright. Did cut out those bad ones and spot welded two used ones in place to test it. Basically the bms was disconnected for a while and yet still works, but it won't auto balance them as voltage differance was very big with a used cell ( 4.19V vs 3,4v ) Cells choosen are LG 18650 M26S which are good cells and not crap generic inr18650's. Pack would be 55.5wh if calibrated correctly then. New it was 49-53wh, but now only like 39wh within a year with almost no usage.
Hi there Yousun, I watched many videos about this, and this one from you is first one that is showing this thing how to bypass BMS protection ! I also on the internet that many of this battery packs for laptop have cycle protection, for example cycle protection is set to 500 numbers of charging - discharging, and after that is simple lock. So for example you have still good cells that it can be used but cycle protecion is ON, and you can't use a battery any more, you must reset that cycle protection, so many people adviced that only good way is to reset Eprom chip before changing cells inside a battery pack. Do you hear about this and what you mean is this correct or not ? I'm also interested to know do you try this method on different battery packs, more precisely from different manufacturers, Sony, Lenovo, Dell, Toshiba... is it working on all of them ? Thanks in advanced.
Yes! The number of cycles is the loss value, reaching 100% usually indicates that the battery is scrapped. This 100% is not easy to get.The only way to clear the number of cycles is to reset the BMS data.
@@yousun2827 Thanks for response. I have a Dell battery 11.1V, 3S2P configuration it uses 6X Sanyo UR18650A 2200 mAh cells. I want to replace it with 6X Sanyo 18650GA 3350 mAh to get ~ 7000 mAh capacity instead of ~ 4000 mAh battery.. Do you think this can work with method that you show ? Of course I can set all cells to about 3.8V old and new battery so BMS will think that they are same.. Here are pictures : i.imgur.com/lkvY0OJ.jpg and i.imgur.com/ANMOMsh.jpg and i.imgur.com/e5NV7mM.jpg I think this guy BQ 8050 is main BMS chip.. If something gets wrong, I found this one on Aliexpress : www.aliexpress.com/item/32947644129.html Do you think I just can order it, and replace with old one and I will have all data 0 and can use in my new battery, or thing is much more complicated and it need to be programed to work ?
It is recommended to use batteries of the same capacity, because BMS writes a fixed capacity, and capacity is the basis for calculating the remaining usage time. The BMS chip has written data inside. Different PCB data is different and cannot be used universally. Correct data needs to be rewritten. Usually the chip data sold is blank, it is recommended to consult the seller.
@@yousun2827 Ok I understand. I found this on couple of videos : ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-I7Llii69YYM.html So basically for some batteries ( don't work with all of them ) we just need to short circuit from cells positive to BMS or electronic output positive terminal so BMS will be reset. Many people confirm this helps. I also found this video : ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-JxnUUPeYId0.html It seems like this guy give some free program that can easily restart BMS chips, it is located here : be2works.com/ If I'm not boring to you can you check this and tell me you'r opinion since you are an expert in this field ? Thanks.
Because they apparently hold bootloader or nowadays just security keys in the nonvolatile memory, once the batteries die for reals, the SRAM content in the microcontroller goes bye-bye, after that, the BMS is effectively bricked. So, just find a way to keep the microcontroller running with the dying batteries removed. It's apparently a safety measure.
GREAT TUTORIAL AAA+++ you are a PRO i have a couple of 9 - 8 cell batteries from the same period (2009) and they are dead and thought maybe could use some of the good remaining cells on them to build a decent 6 cell battery - what do you think?
Im new to this an considering rebuilding an hp battery. Does it work to use a soder iron instead of a spot welder? I don't have one and it would not make sense to get one just for one battery thanks
Hi, I'm hoping you are still reading your comments. It is hard to get updated information on lithiums these days. I have a couple of questions I hope you can help me with. 1) I have an old HP laptop battery. It was completely drained when I left it on the shelf for 3 years. I used it previously for 4, so it is 7 years. I checked the voltage it is 6 cell 18650, 2 each. So 1 parallel cell is dead, but the other 2 are showing around 4V. Can these cells be recharged? 2) My current battery voltage is 4.18V, 4.06V, and 4.03V. Why is the 1st set so high? I was under the impression that lithium batteries lose voltage as they age, not gain? This battery currently only gives me 55% b/c it laptop won't charge if the voltage is above 12.55. Thanks!
If one of the batteries has no voltage, the BMS will lock up and need to be activated for normal use. One of the battery voltages is high, indicating that the battery capacity is insufficient, causing it to fully charge faster. The battery voltage needs to be rebalanced. After the balance, the voltage still appears too high and the battery can only be replaced.
Hello Yousun, is it ok to increase mah capicity? I have lenovo ideapad z460, my don't have any label about mah, only some code, when I searched the code it only indicate the 18650 but the ratings don't have. By the way, you have a great video.
Capacity can be increased, but the remaining time calculation of the computer will not change. It can be used for a while after the remaining time is 0.
@@yousun2827Hello, You can still drive while it shows 0% for a (longer!) while It will show the battery was empty - but it ain't! the remaining power/ load displaying App will not adapt to the new capacity. So it shows less then it' s actually there. Don't panic the "reserve" is bigger then before! Thanks Men you ain't no Punk MC! I would not have found out w/o you (or testing, even no way w/o you). regards. Dipl.-Ing. Miller (dealing w/ rechargeable Batteries since 1980/ and LEDs since 1985)
Youcan use a 600F 2,7Vcapacitor for spot welding, look at this...never more than one (1) second on each spot...then three (3) waiting for seconds...ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-fVCdFzt7q78.html Less than US$10 (ten).
@@yousun2827 I am idiot. I was measuring size using display scale on s7 edge. Turns out its wrong lol. smh stupid samsung. Its 18650. I will order them now :)
The soldering device you use looks like a transformer, but is a pack of batteries with some balancing/charging controllers - what kind of batteries are that and how many Amperes they can deliver ?
Will this also work if I buy a cheap aftermarket battery? Do they need to have the BMS connected all the time as well? I want to try this too but I also don't want to sacrifice my current battery.
I would like to recell the battery in my T520. The Li-ion cells are connected in parallel and then in series to produce the required voltage. If I use new cells at the same state of charge, can I replace one cell in the parallel arrangement at a time until all cells are replaced without activating the fuse in the BMS? Thanks!
Hi! Great video. My battery pack (VGP-BPS13/S) have inside 6 18650 (SE US18650GR). It's 2100mAh each. Question: Can replace them with the Panasonic NCR18650B? It's 3400mAh. The battery management circuit can handle them?
it is not a perfect tutorial you did not discuss the counters that count and you cannot replace battery switch have been charged and recharged according to the counter with new batteries which the counter does not recognize it will not work the counter will get confused
Greetings Master Yousun. Thank you for the laptop 18650 Li-Ion battery assembly and replacement video. May I make a suggestion? Since you are not explaining any thing, is it necessary that the viewers need to listen to the traffic symphony? At one stage the shutter closing sound was so alarming and I was like what the..... ! I’m still interested in buying the spot welder if you can assemble one for me or a kit shipped to me. Some one in England or Germany is selling the same as a kit, without Battery or the spot welding Electrode handle. Can SUNKKO Electrode holder be used? Let me know. Thanks again.
Hi. My Dell laptop battery reports permanent failure. I disassemble and checked the voltage of the 4 cells. cell1. 4.25V cell2. 4.1V cell3. 3.98V cell4. 3.91V. They are connected in series, labelled 14.8V 40wh. Total volatage 16.24. The voltage of cells seems okay but why is it saying failure? In your video, does the replacement cells have protection circuit in each of them?
@@yousun2827 Thank you very much for the reply. Can you do a tutorial about checking and verifying the lithium ion battery voltage.Minimum, maximum and the type of reading which indicates a bad battery.
Hello, thanks. My Dethll laptop battery (for the E5400 Dell Latitude e.g.) has 6 cells. It seems they are switched serial as well. I face difficulties by resoldering them in. Please would somebody be ready to instruct me when I ship photos? I had tried to document the plan before desoldering/ unmount. But w/ the last cell I don't exactly know why it looks like it was a little short-ciruited. Anyway thanks again from DE DIpl.-Ing. Jeppex
Hi there and thank you for the greatvideo, i dont see any other vídeos refering to keep the old battery connected while soldering the new one to save the BMS! I wanted to ask if this is true for all laptop battery, mine is from a Packard bell from 2009, i have to the same procedure? can i put 9 cells in my battery pack instead of 6 it has if i have room in the battery pack case? Thanks in advance Grretings from Portugal
@@aliensanonymous5063 i have replaced with 2400 mah each new cells. Now i get double extra battery backup time. Idk in some models, high amps batteries may not work, if the battery circuit board doesn't support high amps. Also i did disconnected old cells before replacing new one. I didn't know about the BMS. But after replacing new cells, in the battery output terminals, there was not power( maybe the bms thing) but i took a thin wire, hold the wire and bypassed from battery postive terminals to the battery output positive terminals for 1-2 seconds and removed the wire, then it just worked. The battery circuit stared and done. I don't think mah difference would be problem, but make sure rated battery voltage per cells are same or very close to the old cells voltages.
Good morning in these days of (STAY AT HOME) I am going to dismantle laptop battery packs to recover the 18650 lition cells - I would like to know how to identify the good cells with the bad ones, from the volts? Do you have to bring them all to the stello charge level? How to test them individually? Thanks
@@yousun2827 Yousun It is not easy to judge whether the battery is good or bad from the voltage alone. Use of internal battery resistance tester and capacity tester. Thanks - I'm also trying to learn for cells. I measure internal resistance, volts, capacities - for volts and capacities I understand, but for resistance I don't know anything. Some cells also give 880 ohms - I would like to know the right values, which are fine - Thanks
Disconnect the old battery, the BMS thinks there is a problem with the battery, and then the BMS locks up and cannot be used normally. BMS needs to be unlocked again. This measure is to ensure safety.
I did the same, battery is working now - thanks but problem is with gauge - at 6% laptop keeps working for 3+ hours , I charged and discharged 3-4 times completely. But it’s not resetting. I’m using Lenovo x230 44+ battery. Plz help.
@@yousun2827 designed capacity: 62160mWh Remaining capacity: 8910mWh I fully discharged and charged it overnight without using and now current capacity shows 62600mWh Backup time 5:30 , problem almost solved. Only remaining capacity in HWmonitor software shows that previous one. I don’t know if I remove this battery. Calibration will goes back to that low capacity ones. But for now it started working.
@@yousun2827 i just shut down the laptop, removed battery for 5-10sec and when i turned on, WOW - everything is updated and gauge is updated and CPUID HWmonitor shows wear level 0% ... i'm feeling very happy, all thanks to you.
I have 4 camcorder batteries that no longer hold charge as they are 30+ years old, I REALLY need to get this camera working, there is no workaround. Is there anyone I can pay to replace the cells in my batteries? I have tried finding replacement batteries online but there are none. Any help would be amazing. I need this camera for filming a horror movie as soon as possible.
Yousun hey man. The camera is a betamovie 200. The batteries are Sony NP-11. I have 4 of them. 1 of them I already broke open to take a look. I wouldn’t know where to begin
yes, i also tried to do, if i wired like as original but found no voltage on +/- terminal. Actually if you disconnect the wire terminal the circuit go to sleep. this all video are fake.
Hello. I have an old laptop battery, the capacity is only 4800 mah, can i replace its battery with a much bigger capacity battery? Do i need to replace anything, other than the lithium battery? Thank you.
@@yousun2827 Yes, it is recognized by the computer. HWmonitor shows full capacity and current capacity +- 3800 mWh. (according to my calculations it shout be 15V x 3,5A = 52Wh )
