Don't Miss

How To Repair Laptop Batteries

By on February 1, 2017
how to repair laptop batteries










A few days ago I started repairing Laptop Batteries. And in particular the modern Smart Battery Packs. Below my first Pack opened before Repair and Reset. A BQ80201 Controller Board for the Acer Aspire 9411 AWSMi 17 inch Dual Core Laptop. Which didn’t take much time to open.

laptop batteries repair

These packs can’t be fixed by just replacing the 18650 Li-ions by inserting new cells like was still possible with the old Battery Packs (Mostly NiCad and NiMH Packs). Because with the introduction of the Li-ion Battery it is controlled by an intelligent controller Board that keeps track of the Battery temperature, Over voltage when charging, Over current, and prevents Exploding or dangerous Fires . Because Li-ions are very Powerful we need this safety Controller Board as recently was big news when the Samsung Galaxy 7(? I am not familiar with all those new Smart Phones) was cancelled because it caught fire or exploded. And it had cost millions to cancel that Model out of safety concerns. And apparently Li-ion Batteries become very unstable when they get overheated.

I encountered a lot of problems that made it almost impossible for me to repair/fix a Bad Smart Battery at first. I will summarize these points of concern below:

  1. Smart Batteries are read and programmed by using the Philips I2C protocol. Which involves using the 3 wires SDA , SCLK, and GND. And an I2C Adapter Interface.
  2. When we only replace the old Batteries we will notice that when we insert the ‘repaired’ Pack back into the Laptop, it will protest that the Pack is still Bad and it will not charge correctly either. Because the old BAD Pack data is still stored in the Eeprom on the Controller Board.
  3. That’s why we also need to reset/reprogram the previous mentioned Eeprom too. Because the Eeprom on the Controller Board still contained for instance the old Production Date and the Cycle Count of times Charged etc.

Below another peek into the opened Acer Battery Pack (A Sanyo 3UR18650Y-2-QC236 Battery).

fix laptop batteries

Reading the Pack Data and resetting/reprogramming can be easily done with the Full version of the program BE2WORKS. The free demo version only Reads Battery Pack Data. The Full version is not cheap but when we take in account that a single Replacement Battery Pack already easily costs 30 to 60 Dollar/Euro. We earn that investment back after repairing/resetting about 5 Battery Packs.

  1. Because every Battery Pack Connector needs another connector Cable we need to make different versions. Sadly we have to investigate the information of the Connector pins ourself. Like the 7 pins Connector I had to use for my Acer Aspire 9411ASMi Laptop Battery Pack. And my brother’s Acer Aspire 5520G Battery Pack had the same connector but only 10.8V instead of the 11.1V that my Pack had (both Packs about 4400mAh).
  2. I started with the BE2Works demo and therefore had bought the cheap CP2112 USB Adapter to be able to test reading the Battery Eeprom Data. Without that Adapter present the Program will quit. But before reading the Pack by I2C communication is possible we first have to find out the position of the NTC resistor on the Connector. And after I connected that pin to GND the Battery could be read by BE2WORKS. And if the Pack is still in sleep mode we also have to shortly apply an external DC voltage of about 11V onto the Plus and GND connector pins.
  3. Because there was no 7 pin connector Data to be found I started by checking the Plus and GND pins first. And to read out the Eeprom we don’t need to connect the Plus of our Battery Pack to our CP2112 USB Adapter to prevent damage to PC or Adapter. After that I checked with my digital Meter between all pins (except the Plus!!) to Ground if I could measure about 10Kohm that represents the temperature measuring NTC. And connected that pin permanent with GND (on the Connector). And a self made 3 wire connection Cable from the Gnd connection of the CP2112 Adapter was connected to the Battery connector. And the other two wires also from the JP2 connector on the CP2112 represent SDA and SCLK. The CP2112 will be recognized by Windows without having to install any driver.
  4. To prevent blowing up a one-time 4 legged Fuse on the Controller Board that is placed in the Plus Battery Pack connection on the Controller Board, we have to start removing old Batteries by starting removing the Plus wire first, than the lower next Plus, until the last Wire the GND can be removed .

And when connecting new Batteries we for the same reason start in the opposite sequence starting with the Battery GND connection on the internal Controller Board first, going up to the next higher Battery wire, until we finally end with connecting the Plus of the Whole Battery Pack, being the last wire left to connect.

(with 3 x 2 Battery Cells we have to connect 4 wires in total). The 4 legged Fuse (in my case a 12AH3 type Fuse) will get blown if the controller thinks that the Battery is tampered with. Like when the Battery Voltages are connected in the wrong sequence. The Fuse is burned by a controlled FET that heats a resistor inside the Fuse that will immediately open the Fuse. And the Battery Pack Plus is removed from the circuit in the process.  All for safety reasons. 400 of these Fuses only cost about $67 and buying only five of them is also possible. Some say that to prevent this from happening we better at forehand Reset the Controller by connecting that pin to Ground. But if the Protection Flag in the Controller is already Set, the Fuse will probably blow as soon as the Cells are reconnected.

repair laptop batteries

<= The 4 Legged 12AH3 One-time Fuse.

The Battery Connector specs of my 2 now repaired and reset 7 pin connector Packs are as follows:

+ + NTC SCLK SDA – – (gnd)

| | | | | | | <= (7 PIN CONNECTOR)

And as said we do not use the Plus (+) of the Battery Connector other then only for activating the Battery when it is in SLEEP mode as described under point 5.

Before we use and replace the old Li-ions 3.7V (2600mAh) Cells by new ones we have to Spotwelder them with pure Nickel strips onto their contacts. In this case 2 in parallel and that 3 times in Serie. (Parallel doubles the Packs given current). Overheating the Cells by Soldering could make them explode or shorten their life span. (I use a 709A+ Spot Welder for which I had to replace my L16A Weber Fuse automate by a C16A type because the inrush current of the 709A+ was often simply too high).

A Pack with 3 x 2 cells gives about 2 x 2200 mAh, at a voltage of 3 x 3.7 Volt = 11.1 Volt. (In case of my Pack from a Acer Aspire 9411ASMWi 17 inch Laptop).

And in case of my brothers 3 x 2 Cells Pack with another Pack controller, only 10.8V at 4400mAh (Acer Aspire 5520G).

As mentioned before we have to make another I2C Cable to connect to our CP2112 Adapter for any other Battery Pack Connector we encounter. I already ordered the 5 and 9 Pins Male Battery Plugs in case I have to repair/reset those Battery Packs in the near future too. And these are the Chips BE2WORKS can Reset/Reprogram and read: BQ208X, BQ20ZXX, M37512, BQ8030, R2J240, MAX1781, BQ80201, SN8030, BQ20869, BQ30Z55. Below my Brothers old BAD Battery Pack for his Acer Aspire 5520G that costs at least 30 to 60 Dollar/Euro new to replace the old one.

how to fix laptop batteries

And it is good to know that BE2WORKS is able to RESET the PFF (Protection Fuse Flag). But better prevent the above mentioned trigger moments that if they occur set this 12AH3 One-Time Fuse.

laptop batteries spec

As you can see it was still the old BAD Battery Data that is located in the Eeprom. (Cycle count: 223). And it already had lost about 50% of its original Capacity.

After the internal 12AH3 Fuse is blown the BE2WORKS communication with the Battery controller isn’t possible. So we first have to restore that 12A Fuse by placing a short wire over it or by placing a new Fuse. (I used a 0.1 mm thin wire. But I now know how to prevent blowing these Fuses because the Forum and the Site of BE2WORKS were unclear about this subject. And I was told to examine the Controller specs because as they said their program didn’t cover hardware questions. Which didn’t help at all. So now after reading this article any Reader can skip these questions that prevent using the BE2WORKS program the right way!)

be2works adapter

About repairing and replacing old Smart Battery Packs and the price of the Li-ion Cells:

I previously bought 10 of them for about $25/Euro. And those 18650 Cells were all 2600 mAh Capacities (or even more up to 2800 mAh!). The pink/purple Li-ion were original Samsungs according to the Seller!

Which made a big difference quality wise because those 3.7V Cells with names as GTF (9900mAh according to the seller) or Ultrafire (9800 mAh) were a big disappointment. The GTF only gave 963 mAh Capacity, and the Ultrafire cells only 463 mAh !!! To end this article I finally will give some photos of the inside of my brother’s Battery Pack (a Sanyo AS07B31 Pack). Keep in mind that for the same Laptop there are equally useable Battery Packs from different Manufacturers with different Controller Boards but with the same Connector. In case of my Brother’s Battery Pack it took me a lot of time just to find a decent way to open it. It was heavily glued together with double-sided tape, to the Batteries and to the Case. And resetting the BQ 8030 chip took a lot more time compared to my Pack with a BQ 80201 chip. The Eeprom data had to be saved as .bin file (by clicking on the Floppy Disc icon) afterwards. These chips were not sealed, but in case they are BE2WORKS also knows more than 700 Passwords to unseal them. Below the Controller Board with the BQ 8030 DBT chip. And the next Photo shows the position of the 12AH3 4 legged Fuse. Both Photos also show the black wires with the Temperature Sensors that were glued to 2 of the Cells. As can be seen on the Photo after that. And the last Photo shows how in my old Acer Aspire Battery Pack the Wires were connected to the old bad Battery Cells. After opening and removing the Batteries and the Controller Board entirely from the Pack. So If you start by repairing and resetting your old Battery Packs you now know what NOT to do! I hope it was a useful learning experience.

laptop batttery pack circuit board

laptop batteries circuit board

I also bought this complete set of different universal Battery Pack connectors to be used in combination with BE2WORKS which also could be of interest to many readers.

laptop batteries parts

And if I not already told this before, BE2WORKS isn’t capable of reading the Controller Board without internal Batteries connected! Which is the same effect as when the 12AH3 Fuse is blown. And Before anything else ! Be extremely careful with connecting anything to the 18650 Batteries , cause in an unattended moment one of my connection wires short circuited and got up in smoke instantly!

Albert van Bemmelen, Weert , The Netherlands.

Please give a support by clicking on the social buttons below. Your feedback on the post is welcome. Please leave it in the comments.

P.S- If you enjoyed reading this, click here to subscribe to my blog (free subscription). That way, you’ll never miss a post. You can also forward this website link to your friends and colleagues-thanks!

Note: You can read his previous repair article in the below link:



  1. Albert van Bemmelen

    March 16, 2017 at 6:53 pm

    That Spot welder machine looks not bad and has the advantage that
    it only needs 1KW of power. My 709A++ 2 in 1 Spot welder machine
    needs almost twice that amount at 1900 Watt. And in my case I had
    to improve my electric system at home by changing L16 ampère and
    L25 automatic fuses into slower (and higher current providing)
    type fuses. And still now also my mainfuse (which is also only 25A)
    needs to be enhanced too! Which will cost me another extra $200
    dollar/euros extra!
    But my 709A++ has more options, like being able to Spot welder 4
    or 6 upto 8 welder pulses. The more pulses the stronger the
    connection is at the same current. And also the current is much
    higher upto 500 Amps! And it has a solder station with special
    T12 removable heating elements (just replace a defect heater
    element by sticking another one in after pulling the bad one
    And welding pressure also can be regulated, it has a pedal for
    easy foot controlled operation. The Nickel strips can be between
    0.05-0.3mm thick.
    And it also has an extra handy spot welding pen (with also
    2 welding needles in it). Also keep in mind that my Spot
    welder machine costing about 253 euro, came from China why I had
    to pay an extra 28+ euro for importing it to the EU. (My machine
    weighs about 6.9 KG!).

  2. gerald

    March 19, 2017 at 5:21 am

    Hi Albert,
    I can now reset my acer batteries.About spot welding,I've seen this on ebay:
    What do you think about it?I'm afraid with those terms: Electric Leakage Switch Requirement:: 60A or More .
    At home my fuses do not exceed 16 or 32A!

    • Albert van Bemmelen

      March 22, 2017 at 1:38 am

      Fantastic Gerald! I guess you now are able to reset your 4 bad Battery Packs (after of course also replacing the bad 18650 cells)?

      About the 788 you asked. I thought of buying it too myself until I decided that the 709a++ 2 in 1 was a better choice because it also had the hand spot welder tool. And an extra T12 solderstation is more usefull than a charger. Besides every Laptop has its own controlled charger. And else such a charger like the iMax B6 is very affordable too.
      See here:

      So the choice is yours. And maybe also the 788 requires enhanced AC Line Power Fuses.
      (type C16A automatic fuses - Slow type for higher inrush currents - upto at least 63A according to the seller?).

      Nice too hear that you had succeeded fixing your packs, Gerald!
      I only fixed two packs so far. But I'm now trying to fix Makita BL1430 Battery Packs, but I do not know yet what controller they use.

      • Albert van Bemmelen

        March 22, 2017 at 10:03 pm

        What you need to know Gerald is that it is very expensive in The Netherlands to make your Power Cupboard ready for the 63A inrush current of these Spot Welders.
        I just learned that the cheaper 3 x 25A method doesn't apply for me because that would mean that my building society has to replace/convert the complete power installation behind the Main Fuse (now 25A) to a 3 phase installation also (now only 1 phase).
        However the only other and second option of converting the main fuse to 35A is possible but will cost me about 544 Euros!! Still I need to be sure that enhancing to 1 x 35A will be sufficient for the 63A inrush current of my 709A+ device.
        To be safe the rule is to choose the mainfuse at least 2 steps higher than the following fuse. (16A -> 20A -> 25A is 2 steps!) or a difference of about 1.6 x for any following next fuse.

  3. gerald

    March 24, 2017 at 7:22 pm

    Hi Albert,
    It is the reason why I hesitate buying those welders At home my main fuse is max 45A.I have already asked the vendor on ebay for the sunkko788h, the man says I need at least 60A to perform without problems.In my kitchen and bathroom i am protected until 32A (for microwave oven and washing machine).My garage is only 16A fuse protected.I guess I should weld some cells in the kitchen when my wife's at work but that's somehow a bit annoying...

  4. Albert van Bemmelen

    March 26, 2017 at 4:41 pm

    I understand that there are 63A fuses for use at home in other
    But here in my country we can't use or buy them. We also have to ring
    our power delivering company whenever our main fuse is destroyed (on
    paper 35A but in fact now only 25A). That is because that fusebox is
    sealed and we are not allowed to change that fuse ourselfs. It is a
    one-time fuse.

    I can use my 709A++ spot welder machine at home in my garage that is
    fused with a L16A automatic type fuse. But I do not trust doing this
    upstairs at a C16A group that is fused downstairs with a C25A automatic
    fuse, because there are no 2 steps between the C25A fuse and the one-time
    main power fuse. When I use the L16A garage (depository where I store my
    my 2 bicycles and a lot of old scrap electronic parts for repairs) there
    are 2 power fuse steps between the main fuse and the L16 automatic fuse
    (16A -> 20A -> 25A). But still when my main fuse would be destroyed in the proces anyway, they probably wouldn't believe me that I didn't do anything stupid. And have to pay a large bill anyhow. I was thinking of measuring
    the in-rush current with my 400 Amp digital meter. But I'm almost sure it would at least need 63Amps to startup at switch on.
    So if your fuse is L16A (faster type) and resettable and your main fuse
    is 35A it could work.

    • Albert van Bemmelen

      April 3, 2017 at 12:05 am

      By-the-way, Gerald: I regret having bought the 709A+ 2 in 1 spotwelder not only because of the Main Power Inrush problems. Because as it turns out now also the yellow colored square plastic covers on both front welder arms crack/break one after the other.
      And the Seller didn't reply on my complaint that the plastic is just crap material. Its function is probably to keep both arms isolated from each other preventing the upto 800 amps welding both metal arms together. And this also happens because the screw through each plastic cover has to be fastened very thight to keep the copper welding pins in place.
      It is I think therefore not a really well made product and also because of the high inrush problem its asking price is just way too high!


    March 28, 2017 at 12:23 am

    Albert sir i buy this cp2112 adaptor. Can u help me picture in step by step , i program battery chip and backup firmware

    • Albert van Bemmelen

      March 31, 2017 at 2:20 pm

      Nihar, before you buy the expensive BE2WORKS software you must make sure that the Battery Packs you want to repair and reset have a controller chipset that the program is able to reset. Buying the completely build CP2112 pcb board is not expensive and will help you to read any Battery Pack that the software recognizes. But to know what controller is used you often just have to carefully open the Battery Pack to find that out. Because making a new I2C cable for a Battery Pack that is not supported is rather useless. Everything you need to know is written in the repair article and if you have any other question, it probably is already answered in the posts. About backup the battery firmware, it is not always necessary and was opted by the people of BE2WORS after I had reset one of the Battery Packs in my article (the 8030 chip). It is unclear why you need to Backup anything after a Pack is reset to new at 0 cycles. But saving of Battery data after any I2C read-out is possible. But saving data is often different depending on the Controller and Eeprom used in any Battery Pack.

      • vipin

        October 9, 2021 at 5:27 pm

        where to buy battery reset tool & Softwear

  6. Albert van Bemmelen

    April 4, 2017 at 3:48 am

    For anyone interested. Here follows my third Battery Pack connector data:
    _(GND) T NC SCL SDA +(11.74V)
    This is the I2C connection for the HP HSTNN-LB42 6-cell Li-ion pack (10.8V 47Wh).

    Use the top BE2WORKS setting : BQ208x and you will be able to read the Battery pack.

  7. Albert van Bemmelen

    April 4, 2017 at 5:06 am

    PS: I just bought a Schwabe 60533 MIXO Einschaltstrombegrenzer , IP44 Gewerbe, Baustelle 16A 230V (German poduct, about 92 euro) to prevent blowing up my 25A mainfuse after switching on my 709A+ 2 in 1 Spotwelder.
    It should perfectly well work because the inrush limiter can handle upto about 3800 Watt of Power!

  8. Albert van Bemmelen

    April 4, 2017 at 9:26 pm

    Small correction, Its maximum Power is 3500 Watt by the way, which is about equal to 16 Amps x 220VAC. See here:
    It is very cheap on Amazone but since I do not have a credit card I paid about 32 euro more at Dutch Conrad. (when bought at Conrad Germany it also is cheaper compared to Conrad in the Netherlands).

  9. Albert van Bemmelen

    April 7, 2017 at 7:20 pm

    Just tested the yesterday recieved Schwab 16A 230VAC Inrush current Limiter.
    It works great !!
    Worth the money for sure!! (So Gerald, it will certainly work at your home too if there also is a USA current Limiter version).
    I only had to change the USA AC plug with travel adapter plug to a decent EU plug on my 709A Spotwelder because the crappy travel adapter (USA to EU) did not stick/fit in the Schwab inrush current limiter!

    • Albert van Bemmelen

      April 8, 2017 at 3:36 am

      New Battery Pack info (Dell J1KND 11.1V 4400mAh 49Wh).
      9 pins connector
      - - nc BE - SDA SCL + +
      Pack could be read with BE2WORKS BQ20ZXX and BQ208x setting.
      Do not know if I am able to reset this pack also because the pack is brandnew.
      (I therefore haven't opened the Battery pack to see what controller is used).

      • Albert van Bemmelen

        April 10, 2017 at 2:31 pm

        Resetting the above mentioned Dell J1KND 11.1V 4.4Ah 49Wh Battery pack was no problem in the BQ208X setting (BQ2084DBT on board).
        Another Pack fixed as new!

        • Albert van Bemmelen

          April 10, 2017 at 2:51 pm

          Oops: Although I probably also am able to reset the above in my post mentioned Dell J1KND Battery, I can not yet confirm this.

          Instead of the above mentioned Dell J1KND 11.1V 4400 mAh Battery, I actually meant to write about the HSTNN-LB42 Battery that was indeed fixed in the BE2WORKS BQ208X setting yesterday.
          And was the actual Battery I intended to write about instead of the Dell J1KND in my above post. If the Dell Battery also proves to be resettable I of course will mentioned it in a following post.

  10. gerald

    April 20, 2017 at 7:06 pm

    Hi Albert,
    since last reply,I was waiting for my spot-welder which I ordered in china with aliexpress.This is basic model called jst III .I just received it today (one month waiting with UPS).Total cost is about 112 euros + 40 euros intax.I thought it was better than buying in UK or Germany but sucks!!!So i will finally be able to change my lithium cells ...Do you have some advice for buying them on the net?

    • Albert van Bemmelen

      April 21, 2017 at 2:00 pm

      I just read your above post Gerald but wondered what you meant by "I thought it was better than buying in UK or Germany but sucks!!!" ?.
      My seller won't send me new yellow caps for both frontarms of my 709 spotwelder machine. And I only have the machine for about 5 months now. So that service from seller accuni-express sucks too! They do not give any decent reply or help! So I hope this message warns others to buy from them. (waste of 250 euro + 28 euro intax!!). And you better use a Schwabe (DeWalt?) inrush limiter too. It not only limits the inrush current but also any over-current while using your machine (over about 2200 Watt). And odd thing I discovered is that even when you in the event of a over-current event remove or switch-off your spotwelder from the inrush current limiter, the limiter keeps getting hot on its internal NTC(s) while continuesly protecting by mot giving any output, until the Schwabe inrush current limiter itself is completely disconnected from the power line. And after about 10-15 minutes cooling down time, depending on how high the over-current was, the limiter will be operating again. About your question on what Li-ions to buy, I bought the purple Samsung 2600 mAh cells. And some of those were even upto 2800 mAh. And one seller sold Samsung cells that only gave about 2100 mAh, which I sadly only discovered afterwards. PS: resetting Dell battery packs with BE2WORKs still never worked. I was only able to read them.

  11. gerald

    April 21, 2017 at 10:33 pm

    Hi Albert,
    I will have a look for inrush limiter,thanks.

    • Albert van Bemmelen

      April 23, 2017 at 3:06 am

      My Schwabe Mixo-Start Limiter (art.number 60533) prevents blowing up fuses higher than 16A, Gerald.
      It is designed for 16A automatic fuses, of the types B, C and L.
      The Limiter can be powered on 2 to 15 times per minute. (depending on the Power that was used). I noticed that when I select more pulses per welding spot in time, my 709 spotwelder has problems with welding parts together quickly because the Limiter starts limiting the current sooner. So I use 2 or 4 pulses max because that seems to work longer before the current gets limited until the NTC is so hot that it stops giving any current completely. I noticed that the power exceeded the 1900 Watt level easily when 4 and 6 pulses are selected simultaneous (giving 10 pulses). Although my spotwelder was described only using about 1900 Watt, it in fact than was more likely over 3800 Watt! When I only press the 6 pulse button it stops at using not more than 2800 Watt. And when I only press the 4 pulse button the power used is around 2000 Watt. It differs depending how fast the Welder arms are activated and how long. And good to know: that is even when you weren't welding yet, but only were activating the welder arms.

  12. gerald

    May 10, 2017 at 3:12 am

    some news about my experiences:
    first I had to buy a new cp2112,mine was out of order.I took this time silabs which is OK and seems robust.Second ,I had to test my JST-III spotwelder newly received:unfortunately,on the plug adapter the ground was not earthed and blown my fuses on first connection .After changing the plug I managed to revive one battery.But it was a hassle and did not worked either(I damaged a thermal sensor on the pcb,and spot welding is not enough strong on certain cells,breaking the connection).

  13. gerald

    May 10, 2017 at 3:17 am

    And Finally,there also the spot welder power button which stays always on!!
    Hope I'll have some better news someday...

  14. gerald

    May 13, 2017 at 8:23 pm

    some news:first i can now use my spot welder after having replaced 10/16A fuse by 20A fuse.So i finally changed cells in my acer battery.But when I put the new battery on my laptop after a night rest for charging,windows says "no battery".What did I do wrong?

  15. Albert van Bemmelen

    May 14, 2017 at 1:44 am

    Sorry to hear you had those problems with your spotwelder and your CP2112 board, Gerald. I can't confirm having had similar problems with the CP2112 interface board or my 709A+ 2 in 1 spotwelder because I had none.
    And my inRush current problem is solved now.
    I already had answered on your post yesterday 12 May but my post got lost which also happened before. So I will try to upload my answer again today. I use my 709A+ spotwelder with success but only with the protective Schwabe
    Mixo-start inrush limiter as I mentioned before. Because 3800 Watt or more easily destroys my Main fuse without it (maybe DeWalt in your country?). And so should you if you do not want to blow your main fuse at home.
    I only failed to repair my HSTNN-LB42 HP/Compaq Presario C700 third Battery pack.
    Resetting the 10.8V 47Wh pack with BE2WORKS was no problem because that worked flawlessly, but it didn't charge in my laptop after I had replaced all old 18650 cells afterwards. It is a mystery why because I got no error in my Windows, it only doesn't charge or work and all fuses were okay (I only noticed one good 12AH3 fuse).
    Therefore I ordered a new batterypack and it came with a little note that said never to discharge the pack under only 2% charge left. Because that would destroy the pack! So that must have been the problem that occurred after I had removed all the old cells.
    My fourth pack although not resettable with BE2WORKS (it uses a special 68xx cpu chip) was successfully repaired by replacing all 8 Li-ions 18650 in a Mikita BL1430 battery pack. And by removing the original controller board and replacing that with a new replacement board from Aliexpress (about $10 USD/EU), it worked without any problem.
    Glad to hear your spotwelder now works. I can't give you any clues why your Battery pack didn't work, I never had the same problem. Other factors are no guarantee for success. It can be a blown fuse on your controller board or a not activated pack. If your pack doesn't give any output voltage on the + and GND poles at all, it could be that connecting it shortly to an external (carefull not to blow any internal fuse) 11V DC voltage will activate the Pack. But that was already mentioned in the article. Good luck!

  16. gerald

    May 16, 2017 at 2:28 pm

    some news:I successfully soldered my cp2112 for the second time (needed a microscope to verify soldering) with a new chip .Comparing the results with silabs adapter,i saw that be2works 1.39 does not read any battery,neither the adapter was!.I reinstalled a demo version (1.25) on a pc ...and i could read an asus battery with the 2 adapters:strange behavior of the software,isn't it?

  17. gerald

    May 18, 2017 at 4:05 pm

    Hi ,Albert,
    New test rebuilding an acer battery pack:this time,the pcb burnt into flames because red wire touched the fuse at the end of repacking.This is a real nightmare for me ,and I should go fishing instead of bothering me like that...
    Thanks for reading,

  18. gerald

    May 20, 2017 at 2:58 am

    I have a question:once a pack reassembly done,cells and wires connected to pcb,how do you charge the battery?
    Do you use the laptop,or do you connect another source of power?and how do you connect the new battery ,from outside(+ and - slots) or from inside the battery (contact with + and - wires)?And if from outside,do you connect T slot to the ground,in order to initialize the pack?

  19. gerald

    May 20, 2017 at 6:22 pm

    Hi Albert,
    By the way,if I need a power supply,I have a DC 12V5A power generator that I can use.My acer pack gives 12,6V on a multimeter (between + and - wires).Is it ok to charge the cells and for what time?(I don't have a ImaxB6 yet).Sure I would prefer to use my acer laptop to charge it,but I don't know if it will recognize it,as I already tried.

  20. gerald

    May 20, 2017 at 6:39 pm

    Hi again,
    I forgot to mention that I can charge the cells but separately with accupower IQ328+, and I charged the cells a little 300mah before assembling the pack.

  21. gerald

    May 24, 2017 at 1:51 pm

    Most important question:did you have to maintain additional voltage while you were changing your cells?
    And if yes,where did you apply it?(front terminals or in parallel with + and - wires)?

  22. Albert van Bemmelen

    June 1, 2017 at 5:05 am

    Hi Gerald, I didn't expect new questions. So sorry if my answer took this long. Sorry to hear your battery got up in smoke. That never should have happened.
    To answer your first question if I charge a renewed and reset laptop battery? No I just charge it in the matching laptop it was designed for. First charge it, then use it until it is about empty. Then charge it until it is full again. Which should help the Battery and Laptop synchronize to the new state somehow.
    So if the laptop doesn't recognize the Battery it won't work anyhow and something went wrong (or the battery is in sleep mode).
    About your question of strange or not reading packs with BE2WORKS, I noticed that I sometimes just needed to restart the program before it worked again.
    But that can't hurt any battery as long as no programming/resetting was running.

  23. victor

    June 10, 2017 at 8:08 pm

    i have the cp2112 adapter and i have the be2works 4.39 version which have only ten chips. but the issue is if connect the battery with bq8030 chips and all other chip it does not recognise it but the chip is in the software but the only one working so far is the bq208x series so please do you have any idea i am stranded so please if you have any idea please help me.

  24. Albert van Bemmelen

    June 13, 2017 at 2:30 am

    Victor, did you check if your battery maybe still is in sleep mode? It can't be read if the internal battery voltage is too low!

  25. victor

    June 24, 2017 at 2:56 pm

    Albert please when i try bq20z45 mostly it reads the battery data but when i decided to read the chip it talks about discharging the battery capacity to zero i discharged the battery voltage with a fan but it still does not work it still shows discharge to zero.

  26. victor

    June 27, 2017 at 2:09 am

    Albert please when i try bq20z45 mostly it reads the battery data but when i decided to read the chip it talks about discharging the battery capacity to zero i discharged the battery voltage with a fan but it still does not work it still shows discharge to zero.i really need help

  27. victor

    June 27, 2017 at 2:10 am

    I really need help

  28. Albert van Bemmelen

    July 2, 2017 at 5:14 am

    Hi Victor. I know that if you need to discharge your BatteryPack you have to follow the instructions on the BE2WORKS hardware page which involves making a small LM317 circuit. I've never needed it myself so can't assure you how it exactly can be done. And if I'm correct it works as a capacity measuring hardware addition. Maybe the guys at BE2WORKS can help if you got stuck? By-the-way they recently released a new version 4.40 (old version was 4.39).

    I today found another battery pack adapter cable for the 8 pole connector of the HP HSTNN-LB40 11.1V 62Wh laptop battery. The contruction is as follows:
    + + SDA SCL NC - - -
    And of course you have to as always stay of the ++ connector pins!
    I haven't been able to reset the battery because the controllerchip is still unknown but reading the pack with the I2C to USB adapter works splendidly!

  29. Albert van Bemmelen

    July 2, 2017 at 1:30 pm

    Victor. Reading a batterypack should always work nomatter what chip selection you make. So if only MOSTLY your battery reads to PC there probably is something wrong. And ONLY if your chip is the correct identical one you are able to reset the controller board in the batterypack. For instance I got following result when I pressed the green downwards pointing arrow with the in above post mentioned (4 year old and defect) HSTNN-LB40 laptop battery :
    BQ208x => chip is sealed. Trying default password... Failed. Chip is sealed. Discharge battery and reset password.
    BQ20869 => Dataflash read OK.
    MAX1781 => Enter FCC and make reset.
    BQ30Z55 => Unsealed Dataflash read OK.
    R2J240 => Sanyo firmware detected 1. Enter FCC and 2. Reconnect power to PCB.
    And other selections resulted in a BE2WORKS program error or just didn't make sense.

    So you understand, I got different reports and still do not know if my controller is supported. And IF it is supported what right chip needs to be selected. But I was always able to read the battery pack no matter what selection I chose! After a while I only had to shortly recharge the battery pack (on the + and - outside connector pins) a bit because I suddenly wasn't able to just read the battery anymore. Which makes sense knowing the remaining capacity before only was about 242mAh!

  30. Albert van Bemmelen

    July 2, 2017 at 3:19 pm

    Addendum : Above mentioned HP batterypack with new made adapter cable only can be reset with the MAX1781 chip setting in BE2WORKS. Because the controllerboard uses a MAX1781 chip. So I now only need to enter the maximum battery capacity (FCC)and make a reset like described in above post. But before I do that I better first replace all 6 old useless 18650 cells. So you see that the other selections were wrong! And so maybe Victor's battery problem in the posts above being unable to reset his battery is simply because the wrong chip setting in BE2WORKS was chosen.

  31. Albert van Bemmelen

    July 3, 2017 at 4:58 am

    Sadly I today found out that BE2WORKS doesn't support the MAX17817 chip. Only the MAX1780 and MAX1781 controller chips. Which means that I wasn't able to reset a total of two HP HSTNN-LB4x packs. (LB40 and a LB42). The adaptercable worked fine though but HP battery packs are sadly almost unable to repair.
    Although I perfectly was able to read-out the ontroller data. Which means that BE2WORKS often disappoints in its useability. (at a rather high price).

  32. Albert van Bemmelen

    July 5, 2017 at 3:34 pm

    PS: above MAX17817 chip was hard to read because a coating over the chip and its marking protected it from moisture. I hoped it was a MAX1781 but later noticed the extra 7 behind the number which type is not supported by BE2WORKS (only if it was a MAX1781x it would be). I also got a confirmation by the BE2WORKS guys that it wasn't resettable (yet?). And that all supported chip types are mentioned on their site. (Also note that the HP LB40 and LB42 use different controller chips of which I was only able to reset the HSTNN-LB42 Battery. Which, as I previously wrote about, sadly wasn't working after I had replaced all six 18650 cells). Still I'm able to fix a lot of Battery packs and maybe even those Batteries used in e-bikes? Which makes investing in repairing defect Li-ion (and other) Battery packs worthwhile. And if a pack did fail to work, next one probably will. Remember nothing is perfect!

  33. Jose Mario Sarabia Cabrera

    July 10, 2017 at 4:19 pm

    hello, from Mexico, i have a cp2112 and be2works 4,40 i cant read a toshiba pack l305d , just read txt file, but if i want read firmware sends me a access violation address , please help me, thanks for your time

  34. Albert

    July 11, 2017 at 10:50 am

    Hi Jose Mario, do you know what chipset on your battery's controllerboard is installed? If you see that chip's name and number in the list of BE2WORKS it should be resettable. I'm sorry but there is no better way than to open your battery pack to check if the chip on board is supported by BE2WORKS 4.40.
    A violation access address probably means that the wrong BE2WORKS Chip is chosen or the Chip is not (yet) supported. What chips are resettable can be read on the BE2WORKS page. If you for instance have a MAX17817 controllerchip on board, it is not resettable because only the MAX1781 chip is (and maybe also the MAX1780). Sadly there is no list that shows what batterypacks uses what chip. Also because some manufacturers have different controllerboards for the same type of battery. Good luck in resetting your battery pack!

  35. victor

    July 18, 2017 at 8:08 pm

    My cp2112 adapter just refused to be recognised that means it got to stop working and i am tired of buying new ones.I have almost about five which are disabled so i thought of buying th cp2112 chips instead of buying another new one so please can you direct me to a website where i can buy the chips and to be shipped at a fast rate.

    • Albert van Bemmelen

      July 29, 2017 at 1:01 am

      Sorry Victor. I never needed any replacement CP2112 chip so I can't advise you where to buy them. But Gerald in above posts maybe knows where to buy them cheap. (He fixed his defect CP2112 board himself by replacing the chip). Can't believe how many CP2112 board problems you guys have got. Mine never gave me any problem. Maybe you guys connected the three pin wires wrong? (changing SDA and SCL lines wrong probably will not damage the board. But better make sure you never use the wrong wire pin for ground). By-the-way : the CP2112 adapter board will also be recognized as an USB device on your PC without any of the SCL/SDA and ground wires connected!

  36. Frank

    September 8, 2017 at 7:28 pm


    nice to meet a fellow countryman here, and again nearby (I'm from Tilburg).
    I have a question. I own a pair of battery packs for a Medion tablet pc (1 for the tablet and the other for the docking station).
    Now, the LiPo cells were too widely discharged because the laptop was too unused for too long, and did not want to load the cells anymore (Windows says: battery connected, uncharged).
    I opened the packages, and the cells were loaded without the BMS with an intelligent charger, but unfortunately, the bms do not pick it up after I reconnected the cells as original. He does not output on the connector.
    Is there a possibility that you can help me with this? It's so bad to have a laptop that should always be used on the charger.

    Regards, Frank

  37. Frank

    September 8, 2017 at 7:29 pm

    Oh, the bms chip used is: BQ30Z55

  38. Victor

    October 24, 2017 at 6:26 am

    Please i need your help when i reset the 20z45 series and the calibration it shows no output the battery terminal. And still does not charge i tried starting the impendence tracking but it does not respond to the click it doesnt show any effect. Please help me i have a lots of 20z45 to reset. Thanks

  39. Richard

    November 28, 2017 at 5:35 pm

    Beste Albert,

    Graag maak ik gebruik van jou kennis m.b.t. BE2Works, en de BQ20Z45.
    Ik heb hier ongeveer 50 2 cell packs waarvan de one-time fuse eruit ligt. Ik begrijp dat deze fail safe permanent is in de BQ20Z45. Ik wil graag weten of BE2Works dit kan resetten, zodat ik, als ik de cellen en de zekering vervang, de packs weer aan de praat krijg. Heb jij hier enige ervaring mee? Ik vind € 220.- een koopje als het mogelijk is, maar erg duur voor een experimentje...
    Uit de data sheet lees ik dat er divers password niveau's zijn. Kan BE2Works daarmee overweg?

    Alvast dank voor je antwoord.
    I would like to use your knowledge about BE2Works, and the BQ20Z45.
    I have about 50 2 cell packs of which the one-time fuse is out. I understand that this fail safe is permanent in the BQ20Z45. I would like to know if BE2Works can reset this, so that if I replace the cells and the fuse, I will get the packs back on track. Do you have any experience with this? I find € 220.- a bargain when it is possible, but very expensive for an experiment ...
    From the data sheet I read that there are various password levels. Can BE2Works handle this?

    Thank you for your answer.

    • Albert van Bemmelen

      November 16, 2018 at 2:33 am

      Hoi Richard, Ik wil je graag helpen maar ben de BQ20Z45 packs nog niet tegengekomen. Maar volgens BE2WORKS worden die controllers ondersteund en zou het dus moeten werken.

      Hi Richard, I would like to help you but I have not come across the BQ20Z45 packs yet. But according to BE2WORKS, those controllers are supported and should therefore work.

  40. Tigran

    April 14, 2018 at 12:06 am

    If your laptop recognized battery yet and you have same chemistry new battery try to rebuild with following methode..
    Reconect battery wires since high voltage to smaller.(14.4)-10.8-7.4-3.7-0.also carefuly termowire.
    New batteries connect cinse (-) to higher untill (+) 10.8-11.1(14.4-14.8 for old).
    So I was read on some forums its bypass smart chip against blocking.
    Little defererent between capacity is not important.
    Will be better it new battert be charged condiction.
    After reconnect to laptop just full charge battery then discharge and make callibration procedure...
    Its be cheeper solution for rebuild..
    Good luck

  41. orionV

    July 24, 2018 at 6:54 am

    High Albert! Have you experience to repair batteries with Renesas gas gauges like R2J240 or M37512? Is Be2works able to reprogram that gauges?

    • Albert van Bemmelen

      November 16, 2018 at 2:22 am

      No sorry orionV. I never fixed those packs yet!

  42. Koen

    August 25, 2018 at 3:15 pm

    I have a battery pack of which I have replaced the cells. Can you help to reset the eeprom of the battery pack for me?

    • Albert van Bemmelen

      November 16, 2018 at 2:20 am

      Hi koen, read my latest reply above. Fixing battery packs with knowledge on what controller internally is used is difficult enough in itself. But almost impossible without knowing anything about your packs. So make sure what chipset is used AND if BE2WORKS supports your chips.

  43. Albert van Bemmelen

    November 16, 2018 at 2:13 am

    Hi guys! I read your new posts with a lot of questions on my battery pack repair article. I had not checked the article for a long time. And I sadly have no news on fixing other type of battery packs, because I haven't fixed or repaired any new packs until today when I got a bad AS10D51 8 pin connector 10.V 4400mAh/48Wh pack.
    I do not know if I will able to reset the controller in this pack, or what type controller is used. But I did find how to connect it to the BE2WORKS CP2112 module: 1 and 2 are +, 3 and 4 are NC, 5 = SCL, 6 = SDA and 7 and 8 are GND. So reading out the internal Battery specs worked flawlessly. Resetting the controller depends, like I previously wrote, solely on the fact that it must be supported in BE2WORKS chips list!
    Also I got my last BE2WORKS licensed update which was version 4.48. And my version supports these controllers: BQ208X, BQ20ZXX, M37512, BQ8030, R2J240, MAX1781, BQ80201, SN8030, BQ20869, BQ30Z55. But the latest version BE2WORKS is 5.10 which is a Major update which I do not get anymore after all my previous updates (Maximum is only about 3 updates which is a shame with the high offering price of BE2WORKS. Which easily could have provided a life long of free upgrades. Which would be fair!). Using the software still is rather complex with the risk that packs can't be reset/renewed. And the poor BE2WORKS instructions still raises many questions that often only are answered after the user/engineer takes some risks in practice by carefully experimenting. The main problem is always to keep the controller and the board attached to a high enough battery voltage before removing the bad old batteries from the pack which should prevent the possibility of loosing the board's firmware. And at the same time you need to remove cells in the right sequence and attach new cells in opposite order. And everything needs to be done without blowing the internal fuse(s). Even disconnecting the old cells in the wrong order or renewing the cells in the wrong order can destroy a single safety fuse.

    • Albert van Bemmelen

      November 17, 2018 at 1:05 am

      The above mentioned bad 10.8V 4400mAh/48Wh AS10D51 pack with 8 pin connector and six 18650 3.7V lithium-ion cells uses a MAX1786A 28 pins controller chip and is most likely therefore NOT supported by BE2WORKS! And trying to reset the charger´s board chip most likely will fail.

  44. Emo Tilt

    July 28, 2019 at 3:21 pm

    Could you: short circuit the fuse with a big wire in parallel in order to reset the battery with the software, then disconnect jumper wire after battery is reset or will it still blow?

  45. Ayesha

    September 28, 2019 at 10:41 pm

    Peace and hello. We have an HP Omen 17 laptop that is only 15 months old. Yesterday we charged an iphone on it due to some electricity issues without using the charger. This afternoon when my son opened his laptop he noticed the battery was not charging, whilst the charger itself works perfectly. In addition he got the burnt fuse error # 42 for it. Is there any trouble shooting to be done and is repairing the fuse possible given that the laptop is relatively new but out of the warranty period? I'd appreciate your invaluable feedback as we're quite concerned and would not like to entertain the idea of buying a new battery...Thank you in advance.


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.