According to forum rules topic title should contain battery brand and type like printed in the label. 

First post should contain a picture of NLBA1 BatInfo tab. 

Posted by: @tiberius-8

The combination of 4 million will take days

 no need to care about number of key combinations. Just press NLBA1 "Unseal" button. Chip should be unsealed within 5 s. 

Posted by: @tiberius-8

Does anyone have any experience with unsealing this device?

 Yes. Use forum Search option. Hundreds of batteries with bq40z5xx chip were succesfully unsealed and unlocked by our customers. 

@djibattworkshop 

Hi

thanks for your reply. Do you have a price for unsealing ?

I have downloaded the app and saw some prices fro yearly subscription but only require for one time

regards

Tiberius

Posted by: @tiberius-8

but only require for one time

but you already have ev2300 hardware. Did you bought such expensive product to unseal just one battery ?.. 

@djibattworkshop 

Hi

Yes i did pay a bit thinking i could unseal with default key but that wasn't the case.

I dont know if i want to spend even more - its just a learning process for me and if i cant i will just look for a replacement battery

 Do you have battery repair workshop nearby ?.. 

@djibattworkshop 

I dont think so

@djibattworkshop 

The battery is for my autel evo drone which are hard to get in Australia

 Download NLBA1 demo software and read battery parameters. Then paste BatInfo tab snapshot. 

@djibattworkshop 

Will do - thanks

 Check Permanent Failure status by sending these commands 

Register 0x00 WriteWord 0x0053

Register 0x23 ReadBlock 

paste log 

@djibattworkshop 

Thanks

 There is interference from another chip installed on the pcb and which communicates on the same bus. So response from bq40z50 read not correctly. Try to switch off the battery by push button, wait 30s and repeat those commands. 

@djibattworkshop 

I tried a few times and does not seem to be consistant

Thanks for your time and help