LTC3305 Auxiliary cell charging speed

Hi, I would like to use LTC3305.

So, I have a question. Please help me.


I am experimenting with the LTC3305 evaluation board.

Use a super capacitor for the auxiliary cell,
Lead batteries are used for BAT1 ~ 4.

I connected these with the evaluation board.
Current did not flow through the auxiliary cell and the voltage remained at 0V.
(BAT1 ~ BAT4: 12V lead acid battery, auxiliary cell: super capacitor)

The BAL LED (D5) was lit, so I think the status is “Balancing”.

The following was written in p.19 of the data sheet.

After startup, the current is limited by the increase in the resistance value of PTC, and the operation of charging very slowly becomes normal.
* See “Pre-charge of auxiliary cells” below.

Using this as a reference, I left it connected for a while.

Then, there was a voltage rise of about 0.1V in about 10 minutes.
Is this normal for operation?
Please let me know if the charging speed increases as time passes, or the charging speed is very slow in the first 30 minutes.
As a reference, we will share the experimental scenery.

Best Regards,