Don't Miss

New Battery After 2 Cycles Already Defect!

By on January 5, 2019
battery pack repair











In previous repairs I wrote about successful fixing old laptop battery packs.

In this article I write about a new sort of battery pack that turns into useless brand new battery packs even after having been used for only 2 charge cycles. Which happens when you leave the battery pack for a longer time out of your laptop while no longer charged. And at the moment it loses its internal battery voltage below a certain level it won’t function anymore. And neither will be charged in your laptop afterwards anymore.

The battery pack I write about here is for my Compaq Presario C700 laptop. Bad packs still can be read with the BE2WORKS program and its special USB adapter like I wrote about in my previous article. Sadly these new type of battery packs can’t be reset to new packs with BE2WORKS. And sadly BE2WORKS can’t be used with most new batteries because they use new controller chips. Like the 38 pins SH79F329AX chip that BE2WORKS only reads but can’t reset.

laptop battery eeprom reset

Above photo shows my brand new battery that turned into scrap after only been used for 2 charging cycles. Although I kept it on a safe place practical fully charged like the instructions that came with my brand new pack said, it still became useless after it apparently had lost its internal battery charge without being used!

The 3 in series placed x 2 HT Great Power Li-ion batteries likely were of inferior quality because it is not normal that 6 batteries lost their energy after not been discharged other than by its internal controller. The controller, if we read the datasheet, is a special enhanced 8051 type of CPU. Following screen snapshot shows the information that BE2WORKS with the connected special SIL 2112 USB adapter still was able to read after my brand new pack became useless.

laptop battery eeprom files

BE2WORKS in its present state is hopelessly useless. It won’t help in any way in fixing these new kinds of packs with controllers that BE2WORKS simply can’t fix/reset.

laptop battery eeprom ic files

eeprom ic in laptop battery

eeprom ic faulty in laptop battery

repair eeprom ic in laptop battery

Previous photos showed my after 2 cycles already useless replacement 10.8V 5200mAh pack. Notice that my replacement battery had no safety temperature sensor attached. Which makes this product doubtful for another reason, and therefore I won’t buy another pack for my Compaq Presario C700 anymore. Also because my original battery suffered from exactly the same condition, not being able to use it only after it had lost its internal battery voltage.

Although BE2WORKS was able to reset that controller before I replaced the original old 18650 Li-ion cells it won’t be able to reset my new pack with the SH79F329AX chip. It only could reset my old original pack with a BQ 2084DBT controller chip. And most likely this new SH79F329AX controller is programmed with a special JTAG Flash programmer (which also the F for Flash in its name predicts).

This also means that the manufacturer of these replacement battery packs most likely has placed a special firmware program in these controllers. And no doubt the firmware after reaching a certain internal battery voltage level interrupts the battery from operating normally afterwards. Maybe by resetting its internal program state or by blowing a security fuse on its charging board. And after seeing the complexity of the SH79F329AX chip in the datasheet of this CPU it is unlikely that an easy repair or fix is possible to recover from being a taken down battery pack. And for safety reasons any cheap modification to regain the battery function is a bad idea. Also notice that on my new battery controller board besides not having any temperature sensor there is also no fuse installed. There only is a current measure resistance on board. Which means that all safety is software/firmware controlled.

Next JTAG picture came from the controller datasheet.

SH79F329AX controller chip

As I mentioned now both packs were scrap. I will still be able to use the 18650 separate cells in other projects but you have to agree that these kinds of battery packs are just bad products no consumer ever wants to buy!

Next brochure is the warning that came with my brand new pack with the internal HP6000-79 board and the SH79F329AX controller chip on it.

SH79F329AX controller chip datasheet

That told me to never fully discharge the battery! (Leaving 2% charge at minimum and at least 70% charged when not in use. Which I did but still it is dead now!) Next photos are taken from my original bad HSTNN-LB42 battery pack. Now also defect for most likely the same reason.

bad HSTNN-LB42 battery pack

bad HSTNN-LB42 battery pack faulty

faulty ic in laptop battery

faulty eeprom ic in laptop battery

faulty eeprom ic in laptop batteries

Following page about the SH79F329 controller from another controller datasheet shows how the chip is connected to max 5 li-ion cells. And also how the chip can be read using a USB connected PC (the way how BE2WORKS works with its special SIL 2112 adapter). In this same datasheet a special SMARTBATTERY FOR E-TOOL program is used to read and also write to the chip. Sadly these mostly in Chinese written datasheets leaves many questions open.

This special Smartbattery program to write and read the firmware likely will fill the gap that BE2WORKS shamelessly leaves open.

Conclusion: Be aware of these new kinds of laptop replacement battery packs that easily become completely useless. And normally can’t be fixed without the right tools!

After hardly been used and even after put aside fully charged like in the instructions was mentioned, packs become trash. And as result no 2 year warranty can solve these bad designed packs that use special firmware that Manufacturers use and obvious do not share with their battery pack buyers.

Firmware that surely won’t be able to measure the pack’s temperature when as in my brand new pack there is no NTC sensor attached!

Also be aware that most new laptops unlike my Compaq Presario C700 that works perfectly on the adapter only, newer laptops won’t work correctly without any battery pack inserted. Which is the case with laptops like my refurbished Lenovo 430S laptop that although it works on only the adapter,

doesn’t show any played video without showing artifacts while decompressing the video when the battery is not inserted.

sh729f329 n mos 2 to 5 cells

Maybe these packs can be safely repaired by replacing old cells by new 18650 li-ion cells while

keeping the pack voltage high enough. But packs that destroy themselves while not even being used is a bad thing to say the least!

I hereby hope to warn anyone interested in fixing these newer replacement battery packs that they are a real problem. It makes resetting or fixing them quite impossible without the right tools.

Addendum! As could be seen on the first BE2WORKS screen copy (VCELL1) , the 2 lower li-ion cells (The black and yellow wires to the controller board. See next photo) were almost gone being discharged far below their minimum 3.7V voltage. They were just about 2.0V and almost unrepairable damaged! The 4 other cells were still fine!

how to repair laptop battery pack

After I had removed them from the pack and tried to recharge them on my OPUS BT-C3100 Battery charger they at first were very unstable and the current went up and down a couple of minutes at around a low 95 mA. And their voltage was just around about 0.18V at first. But after a while they regained their normal voltage and the current went up to a steady 500 mA. After a couple of hours both were charged to 2201 and 2218 mAh at an end voltage of 4.17V.

So to test the pack again I put both cells back and tested the battery in my Compaq Presario C700 laptop. I tried to start my laptop only on my battery but nothing happened. But after also the power adapter was connected and Windows 7 came up, it showed a fully charged battery pack. (Which explains why at first my charging blue led didn’t show). And after I removed the adapter my laptop worked again on only using the now assumably ‘repaired’ battery pack!

It is a fact that previously both bad 18650 battery cells were discharged badly by the controller board itself. And the manufacturer must have known about this problem all along why he warns about this in the brand new battery accompanied instructions.

And because normally any layman wouldn’t know how to open and recharge those 2 cells he is warned. Sadly after this 2 cell repair the battery pack now never really gets charged anymore although my laptop shows a charging battery in its window.

So my final conclusion here is that the special SH79F329AX processor somehow still prevents the pack from a normal charging operation. And the controller board is also the reason why two of the six 18650 Li-ion cells were severely damaged to a dangerous level!

By-the-way: As shown on one of the previous photos, the battery connector has 6 ‘pin’ connections. P+ D C NC T and P-. Never attach the P+ pole (only if the battery needs some small charge if BE2WORKS can’t see it)!

I used a RF 20-6 connector (A set of battery test connectors I bought online) with the SIL 2112 adapter SCL wire connected to pin 4/C, wire SDA goes to pin 5/D, and I connected battery pin T to ground (pins 1 and 2 bridged). Ground of the SIL 2112 BE2WORKS adapter of course also goes to pin 1/P-.

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. Parasuraman S

    January 5, 2019 at 2:01 pm

    Taking up very difficult tasks, completing it professionally and presenting it descriptively! What a dedication!

  2. Albert van Bemmelen

    January 5, 2019 at 4:42 pm

    Thank you Parasuraman. I hoped that resetting these battery packs wasn't made completely impossible but without the right software and the information that the manufacturer obviously keeps secret it is a dead end for these battery packs, and a no go area for repair-engineers.

    • Alkexander

      January 13, 2019 at 2:56 am

      Have same controller on my Dell battery, in my search I found SmartBattery Tools V1.1 specifically for this chip, altough did not use yet and not sure it will help, waiting for SMBUS usb dongle...

      Dowlowad the tool from here and let me know it would help you:

      • Albert van Bemmelen

        January 19, 2019 at 12:56 am

        Thank you Alkexander for that info on the SmartBattery Tools V1.1.
        I regret to have to say that my Sil2112 SMSBUS USB adapter from BE2WORKS is not working with the software from SmartBattery.

        • Felipe Martins de Oliveira

          August 29, 2020 at 6:28 am

          *ola boa noite estou com o mesmo poblema usando esse chip SH79F329AX numa bateria mi drone 4k , pois deixa a tensão abaixa muito agora carrega mas impede de o Drone decolar , consigo reset esse chip , pois as células lipos estão todas otimas .

          * hello good night I'm having the same problem using this SH79F329AX chip in a 4k mi drone battery, as it lets the voltage go down a lot now it loads but prevents the Drone from taking off, I can reset this chip, because the lipos cells are all great.

      • Albert van Bemmelen

        January 19, 2019 at 1:22 am

        For SmartBattery use we probably need one of these MCC+I2C+Bus+Host+Adapter tools:
        But seeing their prices it will be a no-go area for me and I'm sure for a lot more people too!

  3. BEH

    January 6, 2019 at 11:46 am

    Hi Albert
    I have had two articles in this web log about the hp policy in making not friendly products with users and costumers one was about hp scanner another one was about hp printers . this time you are reporting about COMPAQ malfunctioning of battery charger.this is either could be cos of bad design of the machine and or following that older policy to manufacture machine for one time use only.

    • Albert van Bemmelen

      January 6, 2019 at 4:48 pm

      I do not know if it is a bad HP policy that made these Battery packs not worth a single penny Beh. It also could be that they are badly manufactured by an outsourced firm. That is probably what happened with the Samsung Galaxy Note 7 that kept exploding! They blamed it on the battery and not on their hardware. Samsung afterwards clarified that there were two different defects found on the original Note 7s and the replacement units all related to the battery. On the original units the problems could be traced back to a design flaw in the upper right corner of the battery. Electrodes could bend too easily which led to a 'breakdown in the separation between positive and negative tabs, causing a short circuit.
      And if we look at the dangerous way in which for instance China made LED fluorescent 120mm tube lights are manufactured you also will notice the very short distance in which the 230 V wires are connected to the electronic board inside. Which is all but acceptable according to electrical safety rules.

      • Albert van Bemmelen

        January 6, 2019 at 9:03 pm

        I however am almost sure that in this case it is not any of the Li-ion 18650 batteries that are the cause of failure, it is most likely the controller and the design of the board itself that is seriously wrong in this case!

  4. Gary Gemmell

    January 6, 2019 at 11:51 am

    Nice work Albert!

    • Albert van Bemmelen

      January 6, 2019 at 5:02 pm

      Thanks Gary. According to the 2 dislikes I got I guess that not everyone agrees it was. They probably were from the Manufacturer of these bad battery packs and from the guys that made the very expensive and seriously failing BE2WORKS program. The BE2WORKS program did cost me at least 160 euros plus another 20 euros for the SIL 2112 adapter but only helped me to fix 3 older battery packs.
      Which was not worth it!

      • beh

        January 6, 2019 at 8:32 pm

        All these problems is because of there is no any organizations in the world to observe the products of these big manufacturers and give guidance and hints to them to produce standard items and or may be there is such organization ?I do not know? but these companies are so big that they do not listen to anythings and they go in their own way and the rule is old rule for a few dollars more.that is all.

        • Albert van Bemmelen

          January 6, 2019 at 10:59 pm

          I'm afraid that you are right Beh. They should be internationally held responsible for any misdoing environmental wise.

  5. Robert Calk Jr.

    January 6, 2019 at 4:40 pm

    I always read that if you are storing Lithium batteries for long term the batteries should be at about 50% charge. Sorry to hear about your troubles with batteries, Albert.

    • Albert van Bemmelen

      January 6, 2019 at 8:32 pm

      I know Robert, therefore I kept the battery at least 80% charged before I put it aside. It was not used until I tried the pack about 10 months later and noticed that it like my original pack already was completely dead. And since it already was my second battery for the same Laptop that became crap it was like you know what they say: a donkey doesn't hit the same rock twice. So I only bought a new pack once!

  6. Henrique J. G. Ulbrich

    January 6, 2019 at 11:54 pm

    Albert, this has a name (or industrial concept, if you prefer): programmed obsolescence. That´s theft!

    • Albert van Bemmelen

      January 7, 2019 at 2:27 pm

      Thanks Henrique. I'm thinking that even if it was no programmed obsolence it also could be that the processor used here is of inferior quality if it breaks down and fails to control the pack afterwards. And if it was a design flaw in the obviously too complex program code that leads to taken down battery packs the result would be still the same. Not worth the money.

  7. Jim Ballard

    January 7, 2019 at 1:36 am

    Sounds like a "planned obsolescence" scam to me. Nice work!

    • Albert van Bemmelen

      January 7, 2019 at 2:54 pm

      They obviously need to revise their design strategy if they still want to sell these battery packs. Luckily my old Compaq Presario C700 works fine without any pack. Which can't be said from my Lenovo 430s that always needs a battery to prevent any strange artifacts showing up when videos are played back. Sadly new battery packs do not use the 18650 li-ion cells anymore. Like the reserve 11.1V 3.9Ah 44Wh battery pack I bought for my refurbished Lenovo 430s that is much thinner. But at least that pack came with a two year warranty from the Chinese seller KingSener.

  8. Justice

    January 7, 2019 at 8:16 pm

    Wow again thank you Albert, keep up the nice and interesting articles.

    • Albert van Bemmelen

      January 8, 2019 at 7:23 pm

      Thank you Justice for your kind appreciation. Of course I rather wished these things would not happen in a perfect technical world, although writing about bad experiences with these batteries and their chargers probably make good articles. But hopefully it helps to avoid buying the same bad products and at the same time send a message to the Manufacturer that he needs to completely retract their useless products or force them to review the terrible flaws in the design.

  9. Albert van Bemmelen

    January 7, 2019 at 8:35 pm

    By the way: If anyone is interested. This is the Chinese seller that sells Lenovo packs with decent 2 years Warranty

  10. rodrigo

    April 6, 2019 at 7:41 am

    hello I'm having a problem with a drone mi drone I found on your blog talking about this chip with a few cycles I lost a battery I wonder if you have been able to reset the information on the chip.

    • Albert van Bemmelen

      September 29, 2019 at 6:43 pm

      I'm afraid I can't help you Rodrigo because I do not know anything about the drone you mentioned. The chip in the article only was about a laptop battery pack and the controller inside. And I never had problems with resetting any drone battery before. Anyway, I hope you are able to fix the problem (;)

  11. Morgan Flint

    August 14, 2019 at 10:54 pm

    Hello, I have a battery pack with the same controller for Toshiba L50D laptop (compatible with original 51845U-BRS), landed here googling for the controller and I would like to share my experience in case it's useful for others.

    The pack worked OK for about 6 months and then quit working. If you inserted it in the powered laptop, the battery charge icon would show activity as if it was charging but after 1 minute or so would stop. The charge level appeared as 0% and HWInfo program said the same but indicated only a moderate wear level.

    I opened the pack and found that one of the 4 cells (it's a 4S pack) had a severe undervoltage (less than 2 volts) but the rest were at approx. 3.5 volts. As it wasn't the first time I could "revive" a cell like this, I unsoldered the positive lead of the cell (which was the first one in the row) just to avoid the charger to mess with the pack's circuitry, and injected to this cell about 100 mA at the beginning until it reached 3 volts (which happened quite fast) and then up to 0.5A until it reached the same voltage of the remaining cells. Then I resoldered the wire, remounted the pack, connected it to the laptop, connected the laptop power supply and Voilà!, after an initial scare (because the laptop didn't appear to respond to the power button)the thing booted up correctly and the charge icon showed a charge level of 10% and charging. After 2 hours or so it reached 100% and now the laptop is capable to work on batteries with its power supply unplugged, which wasn't possible before (went instantly off after unplugging the PS).

    So I can confirm what you said at the end of your article: I'ts possible to revive one of these "compatible" battery packs with one of the cells discharged. Thank you for the info!

    • Albert van Bemmelen

      September 29, 2019 at 6:34 pm

      Sorry for the late reply Morgan. Normally older articles are not watched and the added growing posts and comments therefore not seen. But to comment on your much appreciated post I am glad that you could revive your battery pack. Sadly today's newer battery packs now likely loose their firmware in case the internal battery voltage to the pack controller board drops in voltage. What happens if you disconnect the battery circuit. So I think you may count yourself lucky that it did not happen with your battery. Cheers!

      • Andy

        December 23, 2019 at 4:01 pm

        Hi Albert,
        Where does one download the software for writing SH79F329AX?

  12. Alvaro

    January 20, 2020 at 1:45 am

    Hi, I have the same SH79F329 in my laptop battery replacement, I took a look to datasheet and discovered pin 22 was RESETB (reset circuit with low state), I put in contact that pin with ground for a pair of seconds, and know my battery charge again (it was always at 0%). Don´t know if know my battery continues charging all the time including when it is fully charged, but at least works. Maybe now there is no protection for charging cycles, what do you think? It is safe or not to use it this way?

    • Alvaro

      January 20, 2020 at 2:12 am

      Maybe my battery has lost its firmware resetting circuit through that pin...

    • Filipe

      February 24, 2022 at 7:18 am

      Thank you I just did that and before there were 0v on the pins and now 10v. I don't have the laptop here now to verify but I think it will work.

  13. Attila Radocz

    May 24, 2020 at 1:24 am

    Hello Albert,

    Nice work with this article!

    Nowadays have you heard that someone managed to write on that chip (SH79F329AX)?

    Thank you and best regards!

  14. Walid

    May 29, 2020 at 9:02 am

    Hi please can you send to us the full version that you have of the softwar BE2Works ??

    • Albert van Bemmelen

      December 17, 2020 at 11:03 pm

      BE2Works costs about 160 dollar/euro and is probably user protected. So I can't copy and give it away for that reason, if that would destroy my user license on the program somehow? I do not think it is updated to work on newer battery packs anymore either why I stopped using it.

  15. paul small

    June 18, 2020 at 11:24 am

    Nice work Albert.! did you think that is any way to modify a 7 pin battery for work in a laptop with 9 pin connector.?

  16. Robert

    June 18, 2020 at 8:53 pm

    Hi Albert,

    I am looking for the second pdf "NMOS 2-5 cell user solution guide".
    So far I have not been able to find it.

    regards (groeten)

    • Albert van Bemmelen

      December 17, 2020 at 11:16 pm

      Where did you say that article was mentioned Robert?

      And sorry for the late response. I normally never look back at long ago published articles.
      And all those who are asking about restetting the SH79F329AX controller. I can't help you there because my battery pack couldn't be fixed either. Although it only was used just about 2 cycles it was no longer functioning. And I stopped fixing these packs after BE2Works no longer fixed new controller packs.

  17. Annas

    November 4, 2020 at 6:06 pm

    Hi Albert,

    I have searched the google for days for an internal flat laptop battery repair but got nothing other than 18650 laptop batteries. so I would like to know if you can help wit my EL04XL Battery for Hp Envy Touchsmart. it doesn't charge at all. it has 0V reading. I have teared it down and found 4 flat lithium batteries connected in series. One of the batteries had a low voltage near 2.4 volts while other have near 3.7V so I charged this battery while connected to the board with an IMAX B6AC charger to almost 3,7V, but still no power on the output.

    After reading posts on this website, I'll be doing the following:
    -try to find the NTC connector and connect it to the ground connector to exit the sleep mode.( if it is in sleep mode)
    -and then checking the output voltage. If no voltage I'll check the protection Fuse for discontinuity.

    Do you think I should fully charge the 4 batteries with my charger?
    Do I need to reset the controller.
    Disconnecting all batteries from the board does it reset the controller?

    Please let me know if I missed anything and if you have any suggestions

  18. Karl

    December 1, 2020 at 9:24 am

    Hello Albert, thank you for the interesting articles you post. I read the data sheet of the damned SH79F329AX controller, I saw that there is reset on pin 22. I also found a Pdf for the reset that I leave you at the bottom of the discussion. In your opinion, if you reset it also cancels the errors recorded? Thanks
    Here is the pdf link

  19. Albert van Bemmelen

    December 17, 2020 at 11:20 pm

    Sorry Karl. And sorry for my very late reply. I stopped fixing these battery packs after my 160 euro costing BE2works program no longer was upgraded and no longer fixed any new controller battery packs.

  20. John L. Smith

    January 5, 2022 at 3:24 am

    This SH79F329AX controller is also used in Xiaomi 4k Drone battery packs. These seem to have a high rate of failure. I have two battery packs - on currently does not work - the flight app reports that the battery has been damaged and cannot be used. Many Youtube videos on how to regain functionality - all focus on unplugging the battery volts sensing connector to 'reset' the system. I find that partially works [ it will allow me to charge the battery] but it still does not function properly in the drone. I also notice that the individual cells [4 of them] are at 4.3 volts when charged. This doesn't seem correct - should be limited to 4.2 volts. Maybe not the controller - maybe the rest of the board components?

  21. Sakhir

    February 13, 2022 at 9:32 am

    Hi, SH79329AX microcontroller work on circuit with 3.0 vdc, after review pin chip this possible reset running firmware by switch off power to chip(disconnect supply to chip) or reset pin 22 to ground pin 24 by resistor 10K ohm. I did the second option for laptop dell battery, first try no success maybe to short time and the second I reset pin 22 to negative supply input (charger installed
    ) with resistor 10K ohm around 500msec. then I input charger voltage coming to battery( I use charger 12vdc), because disassembly condition.

    I hope this will help to other people to reset SH79F329AX. Goodluck

  22. Filipe

    February 25, 2022 at 1:07 am

    I shorted the capacitor where pin 22 goes that shorted it to ground and it reactivated the battery output!

  23. Ionel

    September 15, 2022 at 4:17 am

    be2works is outdated and it was never good, at least for me. I never managed to repair a battery with bq20z70 chip.
    Now I am using NLBA1 PC Software, it works with EV2300 and EV2400, no need to buy NLBA1 analyzer unit. I can unseal most of the chips on the market.


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.