[Solved] Lenovo Yoga TAB 3 10 (YT3-X50L) Battery Not Charging: Replaced Cells, NCR18650B & NCR18500A

Hello colleagues,
I have a problem with the Lenovo Yoga TAB 3 10 tablet model: YT3-X50L.
He came to me completely dead, despite connecting charging did not respond.
I held it on the power supply for several hours and strangely got up, unfortunately the battery was weak and did not hold long, so I decided to regenerate it because it is nowhere available.

I replaced all cells 3pcs NCR18650B 2x and one piece NCR18500A, assembled battery as it should be and put it in the tablet. He charged the battery to 100%, kept it nice until. The next day he stopped charging. There is an inscription: Loading: 0%. Attempt to turn on: the tablet starts up, the android will load, after a while it goes off and returns to charging (0%). Advice where to look for a problem.

I measured the batteries, the voltage that comes out of the battery connector is 4.10V.





The worst thing is that everything was fine, loading, working on the tablet.

And it is not that the new cells must be properly prepared, i.e. perfectly charged, and their capacity theoretically the same. In addition, the electronics of the battery controls their charge and after replacing the cells must be reset .... Unless I'm mistaken, the battery manufacturers protect themselves and set the maximum allowable number of charging cycles after which the management system stops charging.

Check the battery electronics. Maybe you will find information ... anyway, even if you have a device that reads data from such a system and having the ability to change settings, sometimes the system itself is protected by a password and then it is already sweeping ...

What markings do you have on the battery casing, send the picture somehow I don't want to believe that there is no battery for this equipment.

Thanks for the info, the layout that sits in electronics is bq7541 the rest cannot be read even under a microscope. All in all, I did not think about loading all cells into the full body and only assemble the battery.

This is Lenovo yoga Tab 3 10, YT3-X50L designation on the L15D3K32 X50 battery.
I found it but used it, I wanted to regenerate it and everything was ok. if it were new I would buy it: /

EV2400 and one can have fun but it costs a bit. These so that they don't fold sometimes?

Maybe this is the problem? https://www.youtube.com/watch?v=qywgN7gOoD4

Hello,

martiv have you managed to deal with the problem?

I have a similar case. The same model Lenovo YT3-X50L. I got it as a gift, so I don't know its history.

when connected to a charger, shows that it is charging, but the level still displays 0%. When you try to start the tablet gets up, it boots, android starts and the message pops out that the battery is low and turns off.

I took out the batteries to verify and here I have 4.2V on the output, i.e. full. 4.2V on each cell

I would like to point out that my battery was not regenerated, everything was original.

When I start the tablet by entering the service menu, it does not reset, it remains turned on all the time.

any suggestions?

Hello.
I'm joining a thread.

I already have three such cases and only at Lenovo.

1. TB-X605F - broken USB-C connector. Solder connection charging works. The charging light on the tablet is on. Shows on the display that it is charging but all the time 0%. As I check on the laboratory power supply, until the tablet does not signal charging the current from the power supply is 0.45A but when the tablet shows on the display the charging current drops to zero. No wonder it doesn't load, but why does it happen? after disconnecting the power supply it does not go out immediately - that is, there is some voltage in the battery.

2. yt3-x50F - exactly the same - it came to me with a torn out USB connector.
3. yt3-850L - also not charging but this for a change displays the message "battery temperature too low - charging aborted" or something like that.

If anyone has any suggestions, I will gladly accept.
Such miracles are only from Lenovo

In my case, I desoldered BMS from the battery.
I discharged the battery cells and charged it with an external charger to around 3.7V
I soldered the BMS and it started charging normally.
It seems to me that BMS just after desoldering simply reset and it helped, but this is supposition. In any case, the tablet works and charges normally until now.

Thus...

I desoldered BMS. I have charged the battery to 16% with external power supply. I soldered BMS but no charging. I desoldered BMS again and measured the voltage at the BMS output on the battery with power connected to the tablet - the power jumps to 4.3V and drops / stops charging over and over again. I don't have a BMS to substitute for. Maybe someone knows how to check it?

martiv wrote:

bq7541

So bq27541
"One-chamber lithium-ion battery level indicator for battery integration"

So the system reading the total voltage on the batteries.

There is no other layout there, send a photo of the PCB from both sides

Lenovo_YT3-X50L


Lenovo_1051L

bacaking wrote:

Hello.
I'm joining a thread.

I already have three such cases and only at Lenovo.

1. TB-X605F - broken USB-C connector. Solder connection charging works.

And did your colleague check before how did the pins look inside?
Personally, I have such a Lenovo tab M10 on the table and the pads are torn out so I have nowhere to solder the USB-C port and I am looking for a service manual, but from the other side of the port the pins were crossed and it was through the plug of the charger cable so some charging-related systems could go banking.

Hello
I have such a problem that I do not load I thought that the plug but I have two the same tablets I transferred to the other and it's ok batteries I also rescheduled and it is also ok and loading so something is with the disc that does not load what I can do and where to look.
Thanks in advance and regards

Charging socket to check.

nutergsm wrote:

Charging socket to check.

The socket is checked ok and the battery is checked ok

Which battery circuit is this bms?