• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 62 subscribers
  • Views 152 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ28Z610EVM-532: Using just BQ28Z610 to charge a Li-Polymer Battery

Florin Mazilu
Prodigy 50 points
Part Number: BQ28Z610EVM-532
Other Parts Discussed in Thread: BQ28Z610

Hi!

I'm using the BQ28Z610EVM-532 and until now I used the 5V of the USB of my laptop connected to P+ and P-  to charge a 1 series battery configuration and it worked pretty well.

1. Can I use just the BQ28Z610 to charge a Li-Polymer battery? Or is it necessary to use a dedicated charging IC connected to P+ and P-? 

2. What are the dangers of the absence of a charging IC? 

Thank you,

Florin. 

  • 0
    TI__Guru** 102415 points

    Hello Florin,

    Charging without a dedicated charger can be dangerous, I wouldn't recommend using the 5V straight from your laptop to charge Li-Polymer batteries because the voltage is most likely over the max cell voltage and you will not be able to charge close to 100% SOC because it will only be constant voltage charge instead of CC/CV.

    Using a charger with the gauge also makes it easier for the gauge to detect charge termination using taper currents.

    Sincerely,

    Wyatt Keller

  • 0 in reply to Wyatt Keller
    Prodigy 50 points

    Hello Wyatt, 

    The thing is, when I try to charge a fully depleted battery the USB voltage drops to 3.5-3.6 and slowly increases while the battery is charging, while close to full the voltage across P+ and P- is 4.5V and the one across 1N and 1P is 4.2V and it stops when the battery is full, bits 1 and 3 are set in Gauging Status. 

    In this case charging only with BQ28Z610 is still not advisable?

    Thank you,

    Florin Mazilu.

  • 0 in reply to Florin Mazilu
    TI__Guru** 102415 points

    Hello Florin,

    It is up to your system specifications. I would always recommend using a charger with batteries, especially Li-Polymer to make sure they are safe and last for the longest time while using the batteries full SOC.

    It looks like from your testing this could work for your system so it just depends on your needs.

    Sincerely,

    Wyatt Keller