Because of the Thanksgiving holiday in the U.S., TI E2E™ design support forum responses may be delayed from November 25 through December 2. Thank you for your patience.

  • State
  • Locked Locked
  • Replies 5 replies
  • Subscribers 64 subscribers
  • Views 117 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.

BQ25170EVM: can't fully charge a Li-Ion cell

jacob jensen
Prodigy 10 points
Part Number: BQ25170EVM

Tool/software:

Hey

i bought the bq25170evm board to use in a bms system, i have hade some problems with it not charging the batteris i am using fully "CL-18650-MH1/1S2P".

i have tried with a single cell and it just stops charging when it reaches around 3.6 V, i have set it to 4.2 "#5 / R5 / 27k ohm 4.2V / 1-Cell Li-Ion".

i am a bit lost right now i have been trying to figure it out for a few days now and i don't know what to do at this point.

is there someone that could point me to what i am possibly doing wrong ??

thanks in advance

  • 0
    TI__Guru 70006 points

    Hi Jacob

    Couple of things to check:

    1.) Double check the resistance of VSET (TP7) to GND, verify 27k ohms

    2.) Do you any current meters at input or output?  They have caused problems with other customers.

    3.) Double check the Jumper setting, see table 2-1 from User Guide.

  • 0 in reply to Bill Johns
    Prodigy 10 points

    Hey Bill

    i just double checked all the things you where asking about.

    1. yes there is 27K on VSET (TP7)

    2. No i only have a volt meter on the output to see the battery voltage.

    3. all jumpers are setup as shown in table 2-1

    but it still does stop charging when it hits 3V6.

    the only diffence between what is said in 2.3 test instructions and my setup is that i don't have a battery simulator. i do use a normal 18650 samsung cell.

    could that be the problem ??

  • 0 in reply to jacob jensen
    TI__Guru 70006 points

    Hi Jacob

    Can you send photo of the board and test set up?

    What it the STAT LED behavior, is it ON during charge then turns OFF?

    Also ISET pin voltage will indicate current to battery, what is ISET voltage?

  • 0 in reply to Bill Johns
    Prodigy 10 points

    Hey bill

    i do belive i have found the problem, i do belive that i hade a bad NTC when i removed that and just used a 10K resistor it has worked fine for the last 8-9 hours.

    but i can still send the other information if you would like

  • 0 in reply to jacob jensen
    TI__Guru 70006 points

    No -- go ahead and test with the 10k for now.