BQ24171: 96% power consumption ，stopping charger and could not charge to 100% energy

Cooper Zhang1

Part Number: BQ24171
Other Parts Discussed in Thread: BQ28Z610

DEAR：

battery charger is BQ24171，when a battery is charged to 96%, it will no longer be charged. Could you tell me what happened ？ is the trigger condition ？ my schematic is as below attached

status ：1. 100% power consumption, remove adapter， second。when the power is dropping to 92%, then to charge , but only to 96%， it will no longer be charged.

BAT.pdf

over 3 years ago

0 Cooper Zhang1 over 3 years ago

Expert 2190 points

the battery is 2 cell in series_4.35V x 2 =8.7V

0 Michael Emanuel35 over 3 years ago in reply to Cooper Zhang1

TI__Mastermind 33955 points

Can you please include some waveforms of the input voltage, switch node, output voltage, and charge current when this happens? What do you mean it only goes up to 96%? Does the charge voltage go to the right value or is the battery just not full?

Thanks,

Mike Emanuel

Please click "Resolved" if this answers your question.

0 Cooper Zhang1 over 3 years ago in reply to Michael Emanuel35

Expert 2190 points

I mean the battery is not full , only 96%， not 100%，the gauge is BQ28Z610 。

0 Michael Emanuel35 over 3 years ago in reply to Cooper Zhang1

TI__Mastermind 33955 points

The requested waveforms could assist in my diagnosis.

In addition, if the impedance to your battery is too long from the battery charger, the battery may not be fully charged. For example, the charger regulates the SRN pin to 8.7 V. Then it enters constant voltage mode. The charger will slowly bring down the charge current until termination. However, if the impedance is so long that by the time termination is reached the actual battery voltage is not 8.7 V, your battery would not be fully charged.

Thanks,

Mike Emanuel

Please click "Resolved" if this answered your question.

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BQ24171: 96% power consumption ，stopping charger and could not charge to 100% energy